BIL 150- Exam 5

A region's climate determines the composition and diversity of its ______ (plant life). Climate and flora directly affect the composition and diversity of the _____ (animal life).

flora; fauna

Lecture 20

Lecture 20

Lecture 22

Lecture 22

Lecture 23

Lecture 23

Lecture 24

Lecture 24

Lecture 25

Lecture 25

Lecture 27

Lecture 27

Deuterostomes Characteristics

*Symplesiomorphies with Protosomes*: ∙Bilaterally ∙Symmetrical ∙Triploblastic ∙Coelomate *Synapomorphies* ∙*Blastopore becomes the anus* ∙Secondary opening becomes the mouth ∙Coelom is (usually) derived via *enterocoely*. ∙Cleavage is *radial*. ∙Cleavage is *indeterminate*. ∙*Nervous system* is primitively *dorsal*. ∙*Circulatory* system is primitively *ventral*.

Local Geographic Features

1 Other, smaller scale features also can affect local climate. 2. *Coastal mountain ranges*: ∙Ocean wind blowing inland meets mountain ∙As air rises, it cools and precipitates. ∙Dry air crosses to the leeward side ∙*Rain shadow* is a dry area on the leeward side of a coastal range 3. *Topography*: ∙Steep slopes drain well --> xeric conditions -Desert -Chaparral -Dry forest ∙Level areas tend to retain water --> wet conditions -Mesophyte forests -Floodplains -Riparian (relating to or living or located on the bank of a natural watercourse (such as a river) or sometimes of a lake or a tidewater) ecosystems

H.A.M

1, The *Hypothetical Ancestral Mollusk (H.A.M.)* had all the major mollusk characters in their most primitive form. 2. H.A.M., like modern mollusks, had three main body regions: ∙*Foot* (may be highly modified in some species) ∙*Mantle* (thick epidermal layer secretes the shell) ∙*Visceral Mass* (contains all them guts) 3. It's mouth licks up all algae with stabbing things

The Rule of 70

1, The doubling time (in years) for a population undergoing exponential growth can be calculated with the Rule of 70. 2. *70/r* ∙Growth rate must be expressed as a whole number. ∙Growth rate of 5% must be entered as 5, not 0.05 3. For example: A population with a 5% growth rate will double its size in 70/5, or 14 years!

*Frogs and Toads* (Amphibia, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. (All toads are frogs, but not all frogs are toads.* 2. *Frogs* ∙Smooth, mucous skin ∙Capable of fast, powerful leaps 3. *Toads* ∙Drier, warty skin ∙Poisonous parotid glands behind eyes ∙Usually walk to move, and can't leap far

Endocrine System (Vertebrate Characteristics)

1. *A gland is one or more cells that produce and secrete a particular product.* 2. A gland may be: ∙*Exocrine* (product is secreted onto skin or into body cavities) -Ex. Milk, oil, sweat, bile, mucus, digestive enzymes ∙*Endocrine* (product (hormone) is secreted inside the body): ∙*Unicellular* (gland cell) ∙*Multicellular* (gland) ∙*Discrete* - endocrine cells grouped and adhered together (e.g., thyroid) ∙*Diffuse* - scattered among non-endocrine cells (e.g., intestinal epithelium) ∙*Intermediate* - between discrete and diffuse (e.g., Islets of Langerhans)

*Acclimatization* (Individual Adaptation)

1. *Acclimatization* is a physiological, biochemical, or anatomical change that occurs within the lifetime of an individual organism. 2. Acclimatization results from chronic exposure to a naturally occurring environmental challenge. 3. It usually involves a change in gene expression, reflected in phenotype.

*Osmoregulation* (Regulation vs. Conformity)

1. *Anadromous* fish migrate from marine to freshwater to breed. 2. *Catadromous* fish migrate from freshwater to marine to breed. 3, Both types of fish have sophisticated osmoregulatory systems that maintain constant internal salt balance when they move from one habitat to another. 4.They are *osmoregulators* 5. Echinoderms have a vestigial excretory system. Nitrogenous waste (ammonia) leaves the body via diffusion. 6. Echinoderms have *very little control over their internal salt and water balance*. They are thus strictly limited to marine environments.Their tissues have essentially the same salinity as sea water. 7. They are *osmoconformers.*

*Birds* (Diapsids, Amniota, Reptiliomorpha, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. *Aves* characteristics: ∙*Endothermic homeotherms* ∙*Four-chambered heart* ∙Grasping feet with digits of different sizes ∙Long, flexible neck ∙Maxilla and mandible sheathed in a keratinous, toothless *bill* ∙Epidermal scales modified to form *feathers* -*Uropygial oil gland* (base of tail) for feather waterproofing via preening -Leg scales are comparable to those of other diapsids. ∙*Hollow bones& -Decrease body mass -Are an adaptation for flight ∙Unidirectional respiration via rigid lungs connected to inflatable *air sacs* ∙Breathing *via costal (rib) expansion/contraction* ∙There is *no diaphragm*. So don't squeeze them. They die. ∙Voice box at distal end of trachea allows vocalizations. 2. Sex determination is via the female parent. ∙*Male = ZZ sex chromosomes* ∙*Female = ZW sex* chromosomes ∙(In mammals, male = XY and female = XX sex chromosomes) 3. The avian egg: ∙Contains huge amount of yolk ∙Shell is calcified and brittle 4. Young may be either *precocial* (young are mature) or *altricial* (young is helpless), depending on species.

Productivity (Food Webs)

1. *Biomass* ∙Is the total dry weight of organisms in a given area. ∙Can be calculated for an entire community ∙Is more usually expressed for a species or organism type (e.g., vegetation) 2. *Standing crop biomass* ∙Is the dry weight of given organisms in an ecosystem ∙At any given "snapshot moment" in time 3. *Productivity can be expressed as either*: ∙Energy/unit area/unit time (e.g., Joules/m2/year) ∙Biomass/unit area/unit time (e.g., kg/m2/year). ∙*Gross Primary Productivity* (GPP)( = total primary productivity ∙*Net Primary Productivity (NPP)* = GPP - Erespiration 4. Energy transfer efficiency can be expressed as *E = Pt/Pt-1* where ∙Pt = productivity at level t (e.g., primary consumers) ∙Pt-1 = productivity at the trophic level just below t (e.g., primary producers) 5. Food chains generally tend not to be longer than three to four steps. 6. *Animals are not efficient at utilizing the energy in the food they eat.* (Energetic Hypothesis) 7. The inefficiency of energy transfer between trophic levels limits the length of the food chain. (Energetic Hypothesis). 8. Longer food chains are less stable than shorter food chains. (Dynamic Stability Hypothesis)

Medicines (Biomedical)

1. *Bioprospecting* is searching for plant and animal species that could potentially provide useful compounds, including medicines (studying what plants indigenous people use). 2. 50% of top 10 U.S. prescription drugs come from animals, plants, fungi, or bacteria. 75% of cancer medications are also of organismal origin. ∙*Paclitaxel (Taxol)* -Produced by endophytic fungus in yew trees -Used to treat breast cancer ∙*Captopril (first ACE inhibitor for blood pressure control)* -Derived from tropical viper venom ∙*Vincristine (treatment for Acute Lymphocytic Leukemia)* -Derived from the Madagascar Periwinkle (Vinca rosea) 3. *Tropical rainforest is destroyed at a rate of ~80,000 acres/day.* Unknown numbers of species are destroyed along with them.Most of these extinctions occur without the species ever being known to science.

Two Components of an Ecosystem

1. *Biotic components*- The living organisms 2. *Abiotic components*- Non-living factors such as: ∙Light ∙Temperature ∙Water ∙Nutrients ∙Topography ∙Etc.

Closed Circulatory Systems & Hearts (Vertebrate Characteristics)

1. *Closed Circulatory System*: ∙Heart pumps blood through a circuit of *blood* vessels. ∙Gas exchange and nutrient transfer takes place in the smallest diameter blood vessels. ∙May form one or two blood circuits. ∙Found in all *Annelids*, *Cephalopods* and *Vertebrates*. 2. Modern vertebrate hearts may have two, three, or four chambers. 3. *Two-chambered hearts* (fish) pump blood through *one circuit *of blood vessels: ∙Heart --> gills --> body --> heart 4. *Three- and four-chambered hearts* pump blood through *two separate circuits*: 1. *Systemic* circuit ∙(Heart --> body --> heart) 2. *Pulmonary* circuit ∙(Heart --> lungs --> heart) OR *Pulmocutaneous* circuit (Heart --> lungs/skin --> heart)

Diversity Confers Resistance

1. *Communities with high species diversity tend to be more resistant to disruption by invasive exotic species than less diverse communities.* ∙Diverse species have diverse ecological requirements. ∙Resident species use greater diversity of available resources. ∙Fewer resources are available for incoming invasives. ∙This is especially true of exotics with specific ecological needs. ∙Greater diversity of potential predators and pathogens also may protect the community.

Density-dependent factors

1. *Density-dependent factors* increase in intensity as population density increases. 2. Better adapted individuals will be more successful under density-dependent pressures. 3. Density dependence may be *negative* or *positive*.

Density-independent factors

1. *Density-independent factors* do not affect population growth rate as population density increases. ∙Temperature ∙Rainfall ∙Sunlight (in an open prairie) ∙Natural disasters 2. Such factors affect all individuals in the population, regardless of population density. 3. Periodic major disturbances: ∙Major storms ∙Volcanic eruptions ∙Fires ∙Droughts ∙Floods ∙Tsunamis ...and other natural disasters can cause extreme population fluctuations, regardless of population density.

Doubling Time (Exponential)

1. *Doubling time* is the time required for an exponentially growing population to double in size. 2. As r increases, doubling time decreases. 3. Biotic potential (r) varies considerably among species: ∙Most small-bodied organisms grow quickly, both in body and population size. ∙Large-bodied organisms grow more slowly, both in body and population size.

Ecology vs. Environmentalism

1. *Ecology is a natural science.* ∙An *ecologist* employs hypothetico-deductive methods to address ecological questions scientifically. ∙An *environmentalist* is a person who advocates protection of the natural environment. 2. Most ecologists are also environmentalists, but the two are not the same. 3. One of the first *environmentalists* to apply ecological principles to modern awareness of our role in the biosphere was *Rachel Carson*, author of Silent Spring (1962), in which she documented the adverse environmental effects caused by indiscriminate use of pesticides.

Human Benefits (Ecosystem Services)

1. *Ecosystem services* are the benefits humans gain from healthy ecosystems. 2. These can be grouped into four broad categories: ∙*Provisioning* -Production of food -Filtering of water ∙*Regulating* -Control of climate -Removal of waste -Suppression of pathogens ∙*Supporting* -Nutrient cycles -Oxygen production ∙*Cultural* -Recreational uses -Aesthetic and spiritual benefits 3. Ecosystems provide ~$150 trillion/year in services. This is more than twice as global GDP contribution to human wellbeing. 4. *Land use changes costs $4.3 - 20.2 trillion/year in lost ecosystem services.*

*Aquatic Depth/Pressure* (Eury- vs. Steno-)

1. *Eurybathic* animals are able to tolerate wide range of depth 2. *Stenobathic* animals can tolerate a relatively narrow range of aquatic depth

*Salinity* (Eury- vs. Steno-)

1. *Euryhaline* animals are able to tolerate wide range of salinities 2. *Stenohaline* animals can tolerate a relatively narrow range of salinities

*Temperature* (Eury- vs. Steno-)

1. *Eurythermal* animals are able to tolerate wide range of environmental temperatures 2. *Stenothermal* animals can tolerate a relatively narrow range of environmental temperatures

*Overall Habitat Conditions* (Eury- vs. Steno-)

1. *Eurytopic* animals are able to tolerate wide range of habitat conditions 2. *Stenotopic* animals can tolerate a relatively narrow range of habitat conditions

Feedback (Homeostasis)

1. *Feedback* from a controlled variable is facilitated by communication between body systems. 2. &An animal body constantly sends itself messages about its internal state.* 3. If an internal variable changes, metabolism is altered to achieve homeostasis.

Fire Adapted Woody Plants

1. *Fire-activated Seed* 2. *Thermal Insulation* 3. *Resprouting* 4. *Prolific Flowering* 5. *Tall Crowns*

Ecosystems and Thermodynamics

1. *First Law of Thermodynamics*: Energy can be transformed from one form to another, but can be neither created nor destroyed. 2. Ecological systems: ∙Change energy into matter ∙Change matter into energy. ∙Gain and lose matter and energy to other systems ∙Achieve a *dynamic steady state* when gains and losses are in equilibrium

Geometric Growth: Intermittent Reproduction

1. *Geometric growth* can be expressed as: *Nt = N0λ* where ∙N0 = current population size ∙Nt = future population size ∙λ = ratio of population size at one time interval (e.g., year) to population size at the preceding time interval ∙If births > deaths, then λ > 1.0 ∙If births < deaths, then λ < 1.0 ∙(λ cannot be negative, because population size cannot be negative.)

Human Influence (Anthropogenic) on Ecosystems

1. *Homo sapiens interacts--directly and indirectly--with more species than does any other animal species.* 2. In a few cases, non-human species have benefited from this interaction. (ex. cockroaches in caves) 3. *Far more often, the impact of human interaction is negative.* 4. Most species that have existed on earth are now extinct. But the current rate of extinction qualifies as a *mass extinction* similar in scale to those that have occurred only a few times in earth's history.

Individual Adaptation

1. *Individual adaptation* is a short-term response to environmental change. ∙*Physiological*-Some species are able to gradually change their physiological tolerance levels in a slowly changing environment. This ability, too, is controlled by genes that have been selected over evolutionary time. ∙*Morphological*-Morphology may change in response to environment -Fur coat changes: color and thickness change seasonally -Daphnia carapace changes in response to water conditions or to presence of predators ∙*Behavioral*-Behavioral adaptations allow an animal to respond relatively quickly to environmental challenge.

Birth and Death

1. *Infant mortality* is the number of infant deaths per 1000 live births. 2. *Life expectancy* is the predicted average survival of an individual at any *given age*. 3. Infant mortality and life expectancy are inversely correlated. 4. Energy consumption and life expectancy per capita are positively correlated.

*Lampreys* (Petromyzontida (Hyperoartia)/Agnathans, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. *Lampreys* are jawless, eel-like, *catadromous* predators. ∙Live most of their lives in freshwater ∙Migrate from freshwater to the sea to spawn 2. Lampreys use their sharp-toothed, circular mouthparts to latch onto prey much larger than themselves. The lamprey slowly eviscerates and ingests its prey. 3. Lampreys have been introduced accidentally into freshwater lakes, where they wreak havoc on native fish such as salmon and trout.

Ecology and Evolution are Interconnected

1. *Natural selection is driven by ecological interactions.* 2. Phenotype is a product of the interaction of genes and environmental influences. 3. Organic evolution is the change in the genetic composition of populations over generations. 4. *Darwin's four tenets were inspired by his observations of ecological interactions.*

*Negative Feedback* (Feedback, Homeostasis)

1. *Negative feedback* occurs when the system responds to changes in a controlled variable by bringing the variable back to its set point. 2. *Negative feedback, nearly synonymous with homeostasis, is the most common in living systems.* ∙A *stimulus* produces a change to a variable ( regulated factor). ∙A *receptor* monitoring the controlled variable detects the change. ∙*INPUT* travels away from the receptor to the...*control center*, which determines the appropriate response. ∙*OUTPUT* from the control center travels to the...*effector*, which delivers the *response*.

*Nematoda/The Roundworms* (Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. *Nematodes* are the *most numerous, ubiquitous animals on earth.* 2. Thousands of individuals may inhabit a single rotting apple. 3. One gravid female may contain 27 million eggs and lay 200,000 of them in one day. 4. They are *in you* and *on you* and all *around you*. 5. Nematodes may be... ∙*Beneficial members* of soil communities ∙*Commensal* ∙*Parasites* of animals and plants 6. Nematodes are characterized by: ∙A large *pseudocoelom* housing a hydrostatic skeleton ∙*No metamerism* ∙Only *longitudinal muscles* being functional ∙A characteristic *sinusoidal swimming motion* ∙A *simple excretory system* ∙Lack of circulatory or respiratory systems 7. Relatively few nematode species cause disease. But the effects of parasitic nematode effects can range from the annoying to the catastrophic. *Enterobius sp. ("pinworms")* are relatively common intestinal parasites in humans and other mammals. They are generally just annoying and itchy. And they can be passed among mammal species. ∙*Pin worms* ∙*Trichinella* ∙*Heart Worm* ∙*Elephantiasis*

Obligate mutalism (+, +)

1. *Obligatory; both populations benefit* Ex. Animal microbiomes and pollination syndrome

Types of Egg Laying Animals

1. *Oviparous* animals lay eggs that hatch outside the mother's body 2. *Ovoviparous* animals brood eggs that hatch inside the mother's uterus, and and are then released. 3. *Viviparous* animals have young that develop inside the mother's uterus, where they are nourished prior to birth via a connection with the mother's bloodstream (placenta). ∙*Skates* are *oviparous*. ∙*Sawfish* are *ovoviparous*. ∙*Rays* are *viviparous*. ∙*Sharks* may be *any of the above*, depending on species.

*Photoperiodicity* Evolves in Response to Light

1. *Photoperiodicity* is the pattern of biological phenomena driven by the regularly recurring (daily and seasonal) changes in light and dark. 2. Photoperiodicity can cycle ∙On a 24-hour cycle (*Circadian rhythm*) ∙Monthly ∙Annually ...depending on the biological activity (mating, sleep cycle, hibernation, etc.).

*Eutheria* (Mammalia, Synapsida, Amniota, Reptiliomorpha, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. *Placental (eutherian) mammals*: ∙Give birth to live young that develop inside the mother's uterus ∙Embryos nourished during development via the placenta 2. This is the most derived and diverse mammalian taxon.There are more than 4400 species in 1000 genera. 3. In marsupials and eutherians: ∙*Spine undulates dorsoventrally* during locomotion.∙(In all other vertebrates, spine undulates laterally.) ∙*Leg joints are rotated under the body* ∙Skeleton, not muscles, support the body's weight -More energy efficient -Allows fast locomotion

Fluctuating Population Size

1. *Populations fluctuate in size naturally over time*. 2. Climatic and seasonal factors can severely decrease populations. 3. Survivors: ∙Benefit from increased resource availability ∙May have increased reproductive output 4. A *population near the maximum density* its habitat can support may be more strongly affected by *small environmental changes*. 5. These *can magnify the effects of density-dependent factors*, causing *significant fluctuations in population size*.

*Positive Feedback* (Feedback, Homeostasis)

1. *Positive feedback* occurs when the system *reinforces* changes in a controlled variable. 2. *Positive feedback is less common than negative*. However, it is critical for normal: ∙Nerve impulse transmission ∙Digestion processes ∙Reproductive processes Ex. Ethylene is a ripening agent which induces ripening in other fruit, which then also release even more ethylene

Psuedocoelomate Ecysozoans (Protostomia, Bilateria, Eumetazoa)

1. *Priapulida* - The Penis Worms 2. *Nematomorpha* - The Horsehair Worms 3. *Nematoda* - The Roundworms

Rossby Waves

1. *Rossby waves* form in the polar jet stream when: ∙*Polar air moves toward the Equator* while ∙*Tropical air moves toward the poles* 2. These waves generate: ∙Low pressure cells (*cyclones*) ∙High pressure cells (*anticyclones*) ...within the Ferrel cells. 3. Cyclones and anticyclones are important generators of weather in the Ferrell cell latitudes. 4. Unusual heat waves and flooding have been occurring in Eurasia with increasing frequency. 5. Major, crippling, winter cold spells have hit the northern U.S. with increasing frequency. 6. Rather than "disproving global warming", these spells are a direct result of anthropogenic climate change. 7. The explanation lies in the *destabilization of the polar vortex and the resulting increase in Rossby wave amplitude.*

*The Acorn Worms* (Hemichordata, Deuterostomia, Bilateria, Eumetazoa)

1. About 350 species of fossorial *acorn worms* inhabit benthic marine communities around the world. 2. The body consists of ∙*Proboscis* ∙*Neck* ∙*Trunk* 3. Acorn worms are of evolutionary interest because they share some characters with echinoderms and some with chordates: ∙Hemichordate *tornaria* larva is very similar to the echinoderm brachiolaria. ∙Like Chordates, acorn worms have *ciliated, pharyngeal gill slits.* ∙Like Chordates, acorn worms have a *dorsal, sometimes hollow nerve cord* (though its homology with the chordate nerve cord is uncertain).

*Tardigrada/Water Bears* (Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. *Tardigrades* are microscopic (~1mm) fluid-feeders. They live in freshwater, marine, and moist terrestrial habitats where they feed on the juices of other organisms. 2. Tardigrades are characterized by: ∙Distinct metamerism ∙Two *chitinous, clawed* appendages per segment ∙An *open circulatory system* ∙A *haemocoel* as main body cavity ∙A coelom reduced to a *gonocoel* and *pericardium*. 3. According to Johann August Ephraim Goeze, who described them in 1773, they lumber around like tiny, aquatic bears 4. Tardigrades have an amazing ability to survive physical conditions that would kill any other organism: ∙Extreme heat and cold ∙Nearly 100% desiccation ∙Vaccuum conditions (zero oxygen!) ∙Desiccation for hundreds of years 5. Investigators are studying tardigrade *cryptobiosis*, a physiological state in which metabolic processes are so reduced as to be undetectable.

Exponential (=Geometric) Growth

1. *The Exponential Model*...describes the growth of a constantly reproducing population uninhibited by biotic or abiotic constraints. 2. A population undergoing *exponential, or geometric growth* increases rapidly in size, with at its maximum intrinsic rate of growth. This can be described by the equation: *Nt+1 = Nt + [(b - d) x Nt]* where ∙*Nt* = population size at time t ∙*b* = average # of births per female (*fecundity*) ∙*d* = average # of deaths per capita (*mortality*) ∙*(b - d)* = rate of change/individual/generation (*net reproductive rate (r)*) ∙*(b - d) x Nt* = net change in # for a given population size 3. A population's *maximum intrinsinc rate of increase (rmax)* (also known as its *biotic potential*) is the number of births minus the number of deaths per generation time. 5. In this model... ∙*Population growth rate is proportional to population size.* ∙*Population growth rate is independent of population density.* In a growing population, change in population size is not constant because there are more individuals reproducing in each successive generation. 6. All organisms have the capacity to grow in this fashion. 7. A species' *maximum intrinsic rate of increase (rmax)* is also known as its *biotic potential*.

Logistic Growth

1. *The Logistic Model* describes the growth of a population whose increase is inhibited by biotic and/or abiotic factors. 2. A population undergoing *logistic growth* exhibits exponential growth eventually stabilized by environmental resistance. 3. A population's *carrying capacity (K)* is the maximum number of individuals its environment can sustain indefinitely. 4. This is described by the equation: *dN/dt = [(rmax)(N)] x [K - N/K]* where ∙*dN* = incremental change in population size ∙*dt* = time interval ∙*rmax* = maximum population growth rate ∙*N* = population size ∙*K* = carrying capacity

*The Lophophorates* (Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. *The Lophophorates* share a unique, tentaculate *lophophore* feeding apparatus. 2. The main clades are: ∙*Brachiozoa* a. *Brachiopoda* - The Lamp Shells (~350 species) b. *Phoronida* - The Horseshoe Worms (~ 12 species) ∙*Bryozoa* a. *Entoprocta* - The Hairy Back Worms (~ 200 species) b. *Ectoprocta* - The Moss Animals (~ 5000 species)

Biome

1. A *biome* is a major ecosystem spread over a wide geographic area, and characterized by specific, dominant plant life. 2. Geographic distributions of biomes correspond closely to *major climate zones.*

The Cohort

1. A *cohort* is a subset of a population consisting of all individuals born in the same year. 2. Populations of long-lived species have more cohorts and more interactions among individuals of different ages. 3. Populations consisting of multiple cohorts tend to be more resistant to extinction than those consisting of only one or very few cohorts.

The Community (Ecological Hierarchy)

1. A *community* is all the populations of species living in a given area. 2. Boundaries: ∙May be fluid ∙May cover small or large areas 2. Species interactions in a community are the manifestation of Darwin's "Economy of Nature".

Conformer

1. A *conformer* is less able to metabolically maintain homeostasis. The environment controls the value of a controlled variable. 2. A species may be a regulator with respect to some controlled variables, and a conformer with respect to others.

Foundation Species

1. A *foundation species* is sometimes called an "ecosystem engineer". 2. An ecosystem engineer causes dramatic, fundamental alterations to the habitat, thus affecting community structure and diversity. 3. The effect can be positive on some species, and negative on others, depending on those other species' ecological requirements. 4. Sea oats (Uniola paniculata) have deep root systems that hold dunes together, preventing erosion. 5. This provides solid habitat for many other seaside species of plants and animals to flourish. 6. Beavers are a foundation species since they make dams which blocks a river and prevents species from growing, and other species come in. 7. Wolves are also a foundation species since their presence increases flora.

Heterotroph

1. A *heterotroph* (Greek hetero, "other" and troph, "feeding") is an organism that feeds on other organisms for its energy. ∙Heterotrophs are also known as *consumers*.

Keystone Species

1. A *keystone species* exerts strong influence on a community by means of its ecological role in that community. 2. *Example*: The *Saguaro Cactus (Carnegiea gigantea)* provides food and shelter for many desert animals. 3. These resources allow greater diversity of animal species. 4. Ex. *Mangroves* and *sea oats* are a keystone species which keep erosion at bay. That's why invasive Australian pines are so terrible since they aren't adapted for hurricanes.

Parasitoidism (+ , -)

1. A *parasitoid* acts as a parasite of a host until: ∙Metamorphosis from juvenile ∙Onset of reproduction 2. At that point, it usually kills the host with its emergence.

Density and Distribution

1. A *population's density* is the *number of individuals per unit area (land) or volume (air/water)*. 2. A *population's dispersion* is the pattern of *spacing among individuals*. 3. Spacing can be ∙*Random* ∙*Clumped* ∙*Uniform* 4. These patterns can aid prediction of *intraspecific interactions*.

The Population (Ecological Hierarchy)

1. A *population* is all the individuals of the same species living in a given area. 2. Boundaries can be: ∙Natural (forest edges; shorelines, etc.) ∙Artificial (country s; state lines, etc.) 3. A population's: ∙*Geographic range/distribution* is the extent of land or water within which it lives. ∙*Abundance* is the total number of individuals. ∙*Density* is the number of individuals per unit area or volume. ∙*Composition* is its makeup in terms of age, sex, or genotype.

Categorizing Species on the basis of Energy Source

1. A *producer (autotroph)* converts chemical energy into organic matter. 2. A *consumer (heterotroph)* obtains its energy from other organisms: ∙*Primary (1°)* consumer feeds on producers ∙*Secondary (2°)* consumer feeds on primary consumers ∙*Tertiary (3°)* consumer feeds on secondary consumers ∙*Quaternary (4°)* consumer feeds on tertiary consumers 3. A *mixotroph* can switch between autotrophy and heterotrophy 4. A *scavenger* consumes dead animals. 5. A *detritivore* breaks down dead organic matter (detritus)into smaller organic particles. 6. A *decomposer* breaks down organic detritus into inorganic elements that can be recycled by autotrophs.

Regulator

1. A *regulator* uses metabolic means to maintain homeostasis in response to environmental changes. A regulator can control the value of a controlled variable. 2. A species may be a regulator with respect to some controlled variables, and a conformer with respect to others.

Negative Density-dependence

1. A factor that causes a population's growth rate to *decrease* as population size increases is a *negative density dependent factor*. 2. Common negative factors include limiting resources such as: ∙Food ∙Physical space ∙Nesting sites ∙Sunlight (in a shady forest) ∙Water (in a xeric environment) 3. Examples: ∙Fruit flies raised at different densities, same amount of food. ∙Common Terns colonizing new nesting islands ∙Plants experimentally grown at high densities: -Smaller -Less fecund -Have lower survivorship...than those grown at lower densities.

Positive Density-dependence

1. A factor that causes a population's growth rate to *increase* as population size increases is a *positive density dependent factor*. 2. Typically occurs only at *very low population density*. 2. *Moderate population *increase can increase population growth rate: ∙Increases chances of finding a mate (or being pollinated) ∙Reduces inbreeding suppression ∙Can improve a male-skewed sex ratio 3. Example: Cowslip plants were pollen-limited at low pop'n density, but showed improved seed production with slight population increase.

Parasitism (+, -)

1. A parasite takes up residence in or on a host organism and feeds on the host's body without killing it outright. ∙A *definitive host* houses an *adult parasite.* ∙An *intermediate host* houses a *larval parasite.* 2. The definitive host is usually a predator of the intermediate host. ∙An intermediate host ingests parasite eggs or early larval forms. ∙The parasite often encysts in the intermediate host's tissues. ∙When the definitive host eats the intermediate host, the life cycle is completed. ∙The larval parasite metamorphoses into the adult, takes up residence in the definitive host, and begins reproducing.

Population-limiting Factors

1. A population cannot grow exponentially forever. 2. Common results of high population density include: ∙Reduced fecundity (why?) ∙Increased mortality (why?) ∙Increased rate of disease (why?) ∙Possibly increased per capita predation (due to altered predator "search image") ∙Increased contact with toxic waste produced by the population itself 2. A *limiting factor* is any environmental condition that prevents a population from attaining unlimited growth at r.

Population Dynamics

1. A population's *gain* occurs via *births* and *immigration*. A population's *loss* occurs via *deaths* and *emigration*. ∙If population gain = loss, then population size will not change. ∙If population gain > loss, then population size will increase. ∙If population loss < gain, then population size will decrease. 2. *Demography* is the study of changes in the vital statistics of populations over time. 3. (An *actuary* is a demographics expert who determine show likely you are to be dead in the next year, and adjusts your life insurance rate accordingly.)

Crypsis (camouflage)

1. A predator that matches its background can more easily approach its prey, undetected. 2. A prey item that matches its background can more easily avoid detection by a predator. 3. Crypsis can take myriad forms: ∙Simple color matching ∙Evolutionary full-body makeover ...sometimes resulting in morphologies that can be almost unrecognizable as that of an animal.

*Tetrapoda* (Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. A tetrapod has *four limbs*, or is descended from a four-limbed ancestor. 2. Tetrapods exhibit: ∙Loss of gills (at least as adults) ∙Four limbs, each with five digits ∙*Skeletal and muscle adaptations* for terrestrial movement ∙*Cranial adaptations* to keep the head stable during movement ∙A *layer of dead epithelial cells* to slow evaporation ∙A well-developed, *muscular tongue* ∙A *parathyroid gland* to control blood calcium levels ∙*Harderian gland* to lubricate the eyes ∙A *vomeronasal organ* for chemoreception 3. Tetrapoda includes: ∙*Amphibia* (cecilians, salamanders, frogs) ∙*Reptiliomorpha* (reptiles, birds, dinosaurs, mammals, etc.)

Suicidal Lemmings: The Mythology

1. A very old meme is that of the suicidal lemming. 2. When lemming populations increase to a critical density, so it's said, they disperse away from their birthplace. 3. Many are so desperate to escape crowding that they jump off cliffs into the ocean and drown. 4. This "common knowledge" was popularized in the Disney documentary White Wilderness, which was shown to tens of thousands of elementary school kids in the 1960s.

Limits of Tolerance Determine Biogeography

1. Abiotic factors that affect organismal ecology include: ∙Temperature ∙Oxygen levels ∙Water and humidity ∙Ionic composition and concentrations 2. Tolerance to various environmental challenges depends on: ∙Species ∙Natural history/evolution ∙Biogeography 3. Swallowtail butterflies are more diverse at warmer latitudes. ∙Species temperature tolerances differ ∙Host plant diversity is lower at higher latitudes

Acclimation

1. Acclimation is a physiological, biochemical, or anatomical change that occurs in an individual organism in a *manipulated situation*. 2. Acclimation results from relatively short-term exposure to environmental change in a laboratory or other controlled situation. 3. The various aspects of an organism's environmental tolerances help determine its ecological niche.

Atmospheric Circulation Cells

1. Adiabatic heating and cooling around the earth's surface results in the generation of air circulation cells. 2. At the *equator*: ∙Intense sun heats air at the earth's surface. ∙Hot air rises and and undergoes adiabatic cooling. ∙As air cools, its capacity to hold water vapor decreases. ∙Water precipitates as rain near the equator. ∙As rain precipitates, latent heat energy is released. ∙Air continues to warm and rise. 3. At the tropopause: ∙Cold, dry air moves horizontally away from the equator 4. Cells: ∙Hadley Cells ∙The Doldrums ∙Polar Cells ∙Ferrell Cells

Amensalism (0, +)

1. Amensalism occurs when: ∙Species A impedes the success of species B ∙Species A is neither positively nor negatively affected by species B 2. *Amensalism is often the evolutionary outcome of past competition.* 3. *Allelopathy* is the production chemical compounds that inhibit the growth of nearby would-be competitors. 4. Allelopathy is seen in some species of: ∙Plants ∙Protists (e.g., Dinoflagellates, some kelps) ∙Bacteria ∙Fungi ∙Anthozoans

Autotroph

1. An *autotroph* (Greek auto, "self" and troph, "feeding")is an organism that makes its own organic foodvia photosynthesis. ∙Autotrophs are also known as *producers*.

Exotic Species

1. An *exotic species* is a species that has been introduced by humans to an area where it did not evolve. 2. Many ornamental plants fall into this category. As long as they do not escape cultivation and invade native ecosystems, they are not problematic.

Indicator Species

1. An *indicator species* demonstrates, by its: ∙Presence ∙Abundance ∙Lack of abundance ∙Chemical composition ∙...*Some distinctive aspect of the character or quality of an environment.* 2. Examples: ∙Greasewood indicates alkaline, saline soil. ∙Mosses often indicate acid soil. ∙Lichens indicate good air quality. ∙Plant tissue analysis can reveal soil chemical composition. ∙Large amount of deers indicate lack of predators ∙Cattails are an indicator of too much fertilizer ∙Less owls indicate that there is too much deforestation

Invasive Exotic Species

1. An *invasive exotic species* is an exotic species that aggressively displaces native species. 2. Southern Florida is a hotbed of invasive exotics such as the Brazilian Pepper (Schinus terebinthifolius).

Environment is Relative

1. An animal's *environment* comprises the collective physical, chemical and biological components its surroundings. 2. An environment cannot be defined without considering the organism.

Habitat vs. Niche

1. An organism's *habitat* is the physical setting in which it lives. 2. Habitats are *usually distinguished by physical features*, such as dominant plant life: ∙Montane habitat ∙Grassland habitat ∙Stream habitat ∙Desert habitat ∙Forest habitat ∙Etc. 3. Habitat types overlap. Absolute distinctions between them rarely exist. 4. Still, designating a species' habitat gives a good indication of the variety of conditions in which it must survive and thrive: ∙Temperature ∙Light levels ∙Humidity ∙Pressure ∙Oxygen levels ∙Salt concentrations ∙Etc.

*Annelids/The Segmented Worms* (Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. Annelids are the distinctly segmented worms. 2. As a group, annelids are ecologically versatile.They can be found in a wide variety of habitats: ∙Marine ∙Brackish ∙Freshwater ∙Terrestrial ∙Free-swimming ∙Fossorial ∙Tube-dwelling colonial 3. Different species may be ∙Predators ∙Herbivores ∙Filter feeders ∙Detritivores 3. Annelids are ecologically vital members of many ecosystems. 4. Classification of Annelida has been controversial, constantly shifting. 5. Two major Annelid groups: ∙*Errantia* (Latin, errant, "wandering") ∙*Sedentaria* (Latin sedentaria, "sitting") 6. All Annelids exhibit: ∙Distinct *metamerism* (internal and external) ∙A *coelom* serving as a fluid-filled *hydrostatic skeleton* -Closed or partly closed fluid-filled chambers -Flexible, muscular walls -Maintains shape of the animal ∙Well-developed nervous system -*Cephalic ganglion* (ganglion = swollen structure containing multiple nerve cell bodies) -*Ventral, ganglionated nerve cord* ∙A dorsal, *closed* circulatory system with multiple hearts (a pumping organ with with a pathway of oxygenated and deoxygenated fluid and also a lung-like organ) ∙One set of paired appendages on each segment ∙Metanephridia or protonephridia (kidney) comprising the excretory system ∙*Trochophore* larva (free-living larvae) 3. Annelids occupy extremely important ecological niches. Some, such as common *earthworms*, are keystone species. 4. The *fossorial* (= burrowing) earthworm demonstrates how the hydrostatic skeleton facilitates movement and burrowing. 7. Muscles work against turgor pressure to effect movement: ∙*Longitudinal muscles* run anterior/posterior in each segment. ∙*Circular muscles* band around each segment. ∙*Alternating contractions* of the longitudinal and circular muscle sets change the worm's diameter at different points along its length. ∙Thick points anchor in the soil with tiny *setae* on the skin. ∙Thin points disengage the setae and move freely through the substrate.

*Arachnida* (Chelicerata, Arthropoda, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. Arachnida includes spiders, scorpions, mites, ticks. 2. Nearly half of the 100,000 arachnid species are spiders. Take that thought to bed with you. 3. The arachnid body is made up of a: ∙*Cephalothorax* (fused head and thorax) ∙*Abdomen* ∙*Eight pairs of walking legs* on the thorax ∙One pair of *chelicerae* ∙One pair of *pedipalps* (for sensing or feeding)

Stability Follows the Crash

1. As a population reaches environmental carrying capacity, it will sometimes *overshoot K (carrying capacity)*, and then suffer a population *"crash"* before recovering. 2. This pattern may repeat multiple times, with overshoot amplitude decreasing with each iteration. 3. Eventually, the population stabilizes at carrying capacity, and remains so as long as the environment is stable. 4. *Most natural populations exhibit logistic growth.*

Polar Cells

1. At *90°N and 90°S* (poles), cold, dry air falls. ∙*Polar Cells* form between 90°and 60°(N and S). ∙A *polar vortex *(~1000km in diameter) forms at each pole. ∙The vortex can consist of one or two cells. ∙Because this air is dry, *very little precipitation falls at the poles*. ∙Land masses at the poles are frozen deserts.

Life History Strategies: r-selected Species

1. At *low population density*, natural selection should favor strategies that *bring the population close to rmax*. ∙Early sexual maturity ∙Short generation time ∙Increased fecundity 2. Species exhibiting these strategies are known as *r-selected* or *opportunistic*. 3. Opportunistic species are most successful in: ∙Unstable habitats (Weeds in mowed grass) ∙Newly colonized habitats (resources are not limiting) 4. Set the stage for everyone else, ex. rabbits, and dandelions and weeds.

Life History Strategies: K-selected Species

1. At high population density (at or close to K), natural selection should favor: ∙Ability to reproduce with few resources ∙Ability to compete well for limited resources ∙Ability to use resources very efficiently 2. Species these strategies are known as *K-selected ( or *equilibrial*. 3. Equilibrial species establish in stable habitats where population size remains relatively constant as it approaches K.

Cells and the ITCZ Move Seasonally

1. Because of earth's tilt, the *solar equator* moves between 0° and 23.5° N and S over the course of the year. The ITCZ shifts along with the cells. 2. *Seasonal movement of the ITCZ causes seasonal changes in rainfall patterns.* 3. *Rainy season* occurs when the ITCZ is on or close to a particular region. 4. The regions encompassed by the Ferrell cells have less distinct convection currents than the Hadley and Polar cells. 5. In these areas, wind direction can change dramatically. This results in greater variation in temperature and precipitation.

Population Growth and Regulation

1. Given ideal circumstances, populations have the capacity to increase dramatically in size. 2. Population growth rate depends on both intrinsic and extrinsic factors. 3. *Population ecologists* use mathematical models to describe and predict theoretical population growth.

Coriolis Effect

1. Because the earth is spherical, speed of rotation varies with latitude: ∙Equator - 1670km/hr ∙30° N or S - 1445 km/hr ∙80° N or S - 291 km/hr 2. Because of this, anything not firmly attached to the earth itself (air, water) is deflected to the east or west it moves north or south. 3. Surface winds are deflected, causing the *Coriolis Effect*. ∙To the *right* in the *northern hemisphere* ∙To the *left* in the *southern hemisphere*. 4. The *Coriolis Effect* is responsible for: ∙Semi-permanent high and low pressure regions ∙Generation of *prevailing winds* ∙*Northeast trade winds* (northern Hadley cell) blow from east to west ∙*Southeast trade winds* (southern Hadley cell) blow from east to west ∙*Westerlies* occur in northern and southern Ferrell Cells, are more variable than trade winds, and generally blow from west to east ∙*Polar Easterlies* are dry, cold prevailing winds at northern and southern poles, the polar high pressure forces air towards the equator, and the Coriolis deflects winds from east to west. 5. Coriolis Effect also explains why hurricanes rotate: ∙*Counterclockwise* in the northern hemisphere ∙*Clockwise* in the *southern hemisphere*

Ferrel Cells

1. Between 60° and 30°(N and S) air circulates between the two other cells. ∙Ferrell cells form between the Hadley and polar cells. ∙Ferrell cell air movement is driven by that in the adjoining two cells. ∙Ferrel cell is like a "gear" between the Hadley and polar cells. ∙At 60° N and S, warmed, moist air rises and condenses. ∙High rainfall and cool temperatures at 60°N allow temperate rainforests to flourish in some areas.

Eury- vs. Steno-

1. Beyond specific levels of any given factor, a *lethal range* exists. This may differ significantly among species. 2. Outside the lethal range, an individual can adjust its metabolism or behavior to tolerate a challenging environmental stimulus. ∙Organisms that tolerate a wide fluctuation of a given environmental parameter are known as *eury-*(parameter). ∙Organisms that do not tolerate wide fluctuations of a given environmental parameter are known as *steno-( (parameter)

Big Forebrains (Vertebrate Characteristics)

1. Brain morphology reflects natural history. 2. The mammalian neocortex is highly derived with respect to the ancestral vertebrate brain. 3. Birds lack a neocortex or anything homologous to it. However, the avian *dorsal ventricular ridge (DVR)*, also derived from the telencephalon, contains nuclei (neuron clusters) that appear to function as neocortical neurons do.

Tropical Rainforest

1. Characteristics: ∙*Latitude*: between 23.5° north - 23.5° south ∙*Climate*: stable year-round temperature; very high rainfall ∙*Dominant vegetation*: High-canopy trees ∙*Biodiversity*: extremely high (> 50% of terrestrial species) ∙*Productivity*: -high heavily laterized, nutrient-leached soils -Even large trees have shallow root systems ∙*Keystone species*: seed-dispersing birds and mammals (agouti, bats, orangutan -Most ancient of earth's biomes -Species have been co-evolving for millions of years -Many strategies for predation and avoiding predation -*Mature forest floor is relatively clear of plants, as upper canopy blocks most sunlight. A large tree fall can allow germination of pioneer species that may have lain dormant for many years, waiting.* ∙Typical animals (far too many to list): Great Apes, Jaguar, Ocelot, Sloths, Tapir Capybara. Thousands of bat species, bird species, amphibian species. reptile species, insect species 2. Have poor soil 3. Tropical rainforest is currently disappearing at a rate of~6000 acres (4000 football fields) per hour. The global consequences could be dire and difficult to reverse.

Tropical Grassland/Savanna

1. Characteristics: ∙*Latitude*: ~ 25° north - 25° south ∙*Climate*: Extreme seasonal variation. -Mean monthly temperature > 18°C (64°F) -Pronounced dry season (< 60mm/month) -Fire is a major abiotic feature; many plants are fire-adapted. -Wet season has < 100 mm/month -Very deep, humus-rich O horizon ∙Dominant vegetation: Grasses, sclerophyllous trees and shrubs. -Trees often have high canopies due to herbivory by large browsing mammals ∙*Biodiversity*: very high ∙*Productivity*: high ∙*Keystone species*: Grasses; large, grazing ungulates ∙*Typical animals* (too many to list!): Antelope (many species), Zebra Wildebeest, Kangaroo (Australia), Cape Buffalo, Rhinoceros, African Elephant, African, Lion, Leopard, Hyena, Hunting Dog, Cheetah, Warthog, Aardvark, Secretary Bird, Various raptors (hawks, eagles), Vultures, Elapid snakes, Rock Python, Many insects and arachnids 2. Rich soil and rich vegetation

Temperate Grassland

1. Characteristics: ∙*Latitude*: ~ 25° - 50° north ∙*Climate*: Four distinct seasons; harsh, cold winters, very hot summers; typically very dry (precipitation < 100cm/year) ∙*Dominant vegetation*: Grasses, flowering forbs. Very few trees or shrubs -Fire plays an important role in maintaining this biome. -Very deep, rich O horizon ∙Examples: South African *veldt*, Hungarian *puszta*, Argentinian *pampas* (Most has been converted to farmland.), Mongolian/Central Asian *steppe*, North American *prairie* ∙*Biodiversity*: moderate to high ∙*Productivity*: high ∙*Keystone species*: Grasses; large, grazing ungulates ∙*Typical animals*: Bison, Pronghorn Antelope, Przewalski's Horse (Mongolia), Mule Deer, Prairie Dog (spp.), Praire Vole, White-tailed Jackrabbit, Coyote, Red Fox, Black-footed Ferret, Prairie Chicken, Burrowing Owl, Meadowlark, Various raptors (Buteo, Accipiter spp.), Prairie Rattlesnake, Great Plains Toad, Box Turtles, Many insects and arachnids

Temperate Deciduous Forest

1. Characteristics: ∙*Latitude*: ~ 25° - 50° north and south ∙*Climate*: Relatively high rainfall; four distinct seasons ∙*Dominant vegetation*: -Deciduous anthophyte trees and shrubs -Anthophytes have a selective advantage over conifers here because of their greater rate of photosynthesis. -Average photoperiod favors flowering plants over conifers. ∙*Biodiversity*: high ∙*Productivity*: seasonally moderate to high ∙*Keystone species*: Anthophyte plants ∙*Typical animals*: Red Fox, Grey Wolf, Black Bear, Bobcat, Wild pig, Minks, badgers, and other mustelids, White-tailed Deer, Elk, Tree squirrel species, Insects, spiders, slugs, Wild turkeys, Cottontails, Many migratory birds, Turtles, colubrid snakes, Salamanders, frogs Insects, spiders, slugs

Temperate Shrubland

1. Characteristics: ∙*Latitude*: ~ 30° - 45° north -Arid regions with Mediterranean climate a. Southern California b. European and African Mediterranean regions c. Southern tip of Africa d. Southwestern edge of Australia ∙*Climate*: hot and dry, with mild, rainy winters -Fire is a major abiotic formative feature; many plants are fire-adapted. -Droughts are common ∙*Dominant vegetation*: sclerophyllous, xerophytic shrubs ∙*Biodiversity*: moderate to high ∙*Productivity*: high ∙*Keystone species*: Grasses; large, grazing ungulates ∙*Typical animals*: Mule Deer, Black-tailed Jackrabbit, Chipmunk, Ground squirrels, Brush, Rabbit, Peccary (wild pig), Coyote, Gray Fox, Alligator Lizard, Horned Lizard, Many colubrid snakes, Several pit viper species, Road Runner, Many migratory birds, Drought-adapted insects and arachnids: Praying mantis, Ladybugs. honey bees, bumblebees, scorpion

Desert

1. Characteristics: ∙*Latitude*: ~ 30° north - 30° south ∙*Climate*: very dry; temperature extremes -Precipitation < 100cm/year -Summer: extremely hot, dry days, cooler nights -Winter: hot, dry days; nights can be extremely cold ∙*Desertification* is the anthropogenic change of non-desert ecosystems into deserts via overgrazing, urbanization, poor agricultural practices, overuse of ground water, excessive deforestation, climate change ∙*Dominant vegetation*: xerophytes ∙*Biodiversity*: moderate ∙*Productivity*:low -Counterintuitively, desert soils can be very rich in nutrients -Lack of rainfall allows slow accumulation of cations -Just add water: Bloom! -Spring rains can bring spectacular, short-lived blooming of annuals. -*Keystone species*: tortoises, vultures, coyotes, dingos ∙*Typical animals*: Coyote, Desert foxes (e.g., Fennec), Black-tailed Jackrabbit, Desert Cottontail, Kangaroo Rat, Jerboa, Camel, Addax, Oryx, Meerkat, Many colubrid snakes, Many viperid snakes, Road Runner, Bighorn Sheep, Armadillo, 2. Famous North American examples include: ∙Joshua Tree National Monument ∙Death Valley National Park

*Polyplacophora /The Chitons* (Mollusca, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. Chitons are inconspicuous members of rocky intertidal and nearshore marine ecosystems: ∙All *marine* (i.e., living in the ocean) ∙All *benthic* (i.e., living on the bottom substrate, such as rocks, coral, mud, etc.) ∙Characterized by eight separate dorsal plates instead of a single shell ∙Intertidal species have an extremely muscular foot that keeps them anchored in spite of wave action. (Just try to pry a chiton off a rock.) ∙Of all mollusks, the chitons are the *most physically similar to H.A.M.*

*Chordata/The Chordates* (Deuterostomia, Bilateria, Eumetazoa)

1. Chordates share synapomorphies present at least during ontogeny, though they may be lost in the adult: ∙*Pharyngeal gill slits* ∙Dorsal, cartilaginous *notochord* ∙*Dorsal, hollow nerve cord* ∙*Endostyle* or *thyroid gland* ∙*Post-anal tail* ∙Segmentally arranged muscle bundles (*myomeres*) 2. Chordata includes three subphyla: ∙*Urochordata* ∙*Cephalochordata* ∙*Vertebrata* 3. *Vertebrata* is further subdivided into a nested hierarchy: ∙*Gnathostomes*- animals with a mandible ∙*Osteichthyes*- "bony fishes" ∙*Lobe fins* ∙*Tetrapods* - four-legged animals ∙*Amniotes* - animals producing an amniotic egg

Clumped Distribution

1. Clumped dispersion is a relatively common pattern. 2. It may indicate: ∙Local abundance of food or other resource ∙Mating swarms (temporary) ∙Social congregation ∙(Natural selection) a pack of wolves will hunt more successfully than a single wolf in a herd or flock, an individual has a better chance of escape

Species Interactions (Community Ecology)

1. Communities of organisms interact in many possible ways. 2. One can categorize these interactions on the basis of the effect on each of the two interacting populations: ∙Obligate mutualism ∙Protocooperation ∙Commensalism ∙Competition ∙Amensalism ∙Predation ∙Parasitism ∙Parasitoidism ∙Neutralism

Wind (Abiotic Factors and Organic Evolution)

1. Contributes to *erosion* 2. Affects *desiccation rate* in animals, plants, fungi 3. Affects *plant growth form* ∙Wind can cause a tree to bend if there's a lot of wind 4. Affects animal and *plant body temperature* via: ∙Evaporation & evaporative cooling ∙Convection 5. Different forms of the same species generated by differences in environmental factors are called *ecotypes* of that species.

*Temperature* (Abiotic Factors and Organic Evolution)

1. Contributes to erosion and creation of soil 2. Affects evolution of temperature tolerance in living organisms 3. Has direct effects on biological macromolecules

*Water* (Abiotic Factors and Organic Evolution)

1. Contributes to soil erosion and creation. 2. Is a vital component of organism habitats. 3. Natural selection can be driven by: ∙Lack of water in terrestrial environments ∙Lack of solutes in fresh water 4. *Animals* that have secondarily returned to marine environments face different osmotic challenges because the ocean is saltier than when their ancestors left it. 5. *Green plants* have evolved water-related adaptations: ∙*Hydrophytes* are adapted for a very wet environment. ∙*Mesophytes* are adapted for a moderately wet environment. ∙*Xerophytes* are adapted for a very dry environment.

*Crocodilians* (Diapsids, Amniota, Reptiliomorpha, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. Crocodilians and birds split from an Archosaurian dinosaur ancestor. Both are the last living descendants of the dinosaurs. 2. Crocodilia includes large, predatory, semiaquatic reptiles: Crocodiles, alligators, caiman, gharial 3. Crocodilian characteristics: ∙*Ectothermic poikilotherms* ∙*Four-chambered heart* ∙*Respiratory air flow* (like birds) ∙Large, solidly built ∙Long flattened snout ∙Laterally compressed tail ∙Eyes, ears, and nostrils dorsal on the head ∙Non-overlapping epidermal scutes ∙Strong swimmers and sprinters

The Economy of Nature

1. Darwin noted that the interactions of species in nature resembled humans doing business with one another. 2. He called these interactions "*The Economy of Nature*". 3. Ecological understanding is continually expanding. Ecological research is constantly yielding new discoveries.

*Ecdysozoa/The Molting Animals* (Protostomia, Bilateria, Eumetazoa)

1. Ecdysozoan animals are named for *ecdysis*, the molting/shedding of the external cuticle/exoskeleton as the animal grows. 2. We will visit these Ecdysozoan taxa: ∙*Priapulida* - The Penis Worms ∙*Nematomorpha* - The Horsehair Worms ∙*Nematoda* - The Roundworms ∙*Onychophora* - The Velvet Worms ∙*Tardigrada* - The Water Bears ∙*Arthropoda* - The Joint-legged Animals ...all of which undergo ecdysis as they grow. 2. The main structural component of the ecdysozoan cuticle is *chitin.* 3. Chitin is a polymer of the a glucose derivative, *N-acetyle glucosamine.* It is the second most abundant biopolymer on earth. 4. Arthropods use *chitinase* to hydrolyze and soften the inner surface of the cuticle before it can be shed. Many species employ chitinase as a digestive enzyme but it is not usually secreted in large quantities. 5. Some species secrete enough chitin to digest it to some degree. *Chitin digestibility in a particular species appears to correlate with the frequency with which that species ingests chitin.* 6. Molecular data support the monophyly of Ecdysozoa. Within the taxon, however, relationships remain uncertain. One hypothetical phylogeny is shown here. 7. Ecdysozoa includes both: ∙*Pseudocoelomates* ∙*Coelomates* 8. Remember that the *pseudocoelom*, a persistent blastocoel lined only on the parietal side by mesoderm, evolved independently in many Bilaterian lineages. The ecdysozoan pseudocoelom is *not homologous* to the pseudocoelom in other taxa. It may even have *evolved several times within the Ecdysozoa*

*Echinodermata*; The Spiny-skinned Animals (Deuterostomia, Bilateria, Eumetazoa)

1. Echinoderms are characterized by: ∙*Pentaradial symmetry* ∙*Exclusively marine* life history ∙*Slow movement* and *benthic* habit ∙Thin epidermis covered with gills and other projections ∙*Internal calcium carbonate skeleton* ∙*Water vascular system* derived from *coelom* ∙Complete digestive tract ∙Reduced, decentralized nervous system (no brain) ∙Reduced circulatory system ∙Vestigial/non-functional excretory system 2. Although they are pentaradially symmetrical as adults, echinoderms develop from a *bilaterally symmetrical* larva known as a *brachiolaria*. 3. The *water vascular system is derived* from the *coelom*. 4. It is used for locomotion and prey capture. 5. Water... ∙Enters via the aboral *madreporite* (sieve plate) ∙Is distributed radially into the: -*Stone canal* -*Ring canal* -*Ring canals* -*Tube feet*

The Ecological Hierarchy

1. Ecology can be studied from least inclusive to most inclusive levels: 1. *Organismal*- study of the physiological, behavioral, and evolutionary mechanisms individual organisms use to meet environmental challenges 2. *Population*- study of the factors that affect population growth and dynamics 3. *Community*- study of how species interactions affect community structure and organization 4. *Ecosystem*- study of the community and the abiotic components of its environment 5. *Landscape*- study of the interactions between adjacent ecosystems 6. *Global*- study of matter and energy exchange and species distributions across the biosphere

Energy Pyramid

1. Efficiency with which trophic levels convert energy from the previous trophic levels varies across ecosystems, ranging between 5% - 20%. 2. General Rule of Thumb: *Only 10% of the energy in organisms eaten by those in the next trophic level is converted to the higher-level consumer's biomass.* 3. The reduction in available energy at higher trophic level can be expressed with a *trophic energy pyramid*. 4. The Energy Pyramid is reflected in the *standing crop biomass* of each trophic level. 5. The higher the trophic level, the lower the biomass. 6. In general: *The higher the trophic level, the fewer the individuals.* 7. More individuals can exist at lower trophic levels. *When humans eat lower on the food chain*: ∙Energy loss is reduced ∙More energy is available ∙More individuals can be fed

Energy Flow through Ecosystems

1. Energy Flow begins with *primary productivity*, the amount of light energy converted to chemical energy (organic matter) by community autotrophs over a given period of time. ∙*Energy* makes a one-way trip through ecosystems as it increases entropy. (*Second Law of Thermodynamics*) ∙*Matter* is continually recycled through ecosystems. (*Law of Conservation of Mass*)

Exponential Growth: Constant Reproduction

1. Exponential growth also can be expressed as: *dN/dt = rN* where ∙t = time interval ∙N = initial population size ∙r = intrinsic growth rate (birth rate - death rate) ∙dN/dt = change in population size over a time interval 2. Remember... ∙*Population growth rate is proportional to population size.* ∙*Population growth rate is independent of population density.*

The Role of Fire in Warmer, Drier Biomes

1. Fire is an important influence in warmer, drier biomes. 2. In grassland and chaparral/shrubland biomes: ∙Moisture is intermediate (but sufficient for fuel to accumulate) ∙Seasonal droughts occur (dries out fuel) 3. This promotes seasonal fires. ∙Grasses and herbaceous *forbs* are favored woody plants may be fire-adapted -Fire-activated seed release or germination -Fire-resistant insulation (bark, dead leaves, etc.) -Storage roots or protected buds for re-sprouting -Fire-activated flowering -Tall crown with little low foliage

Human Population Parameters

1. For its *first 200,000 years* of existence, our species has exhibited population growth characteristics typical of a *K-selected species*. 2. Since the mid-1800s, however, human population growth began to take an upswing. 3. From 1870 to 2000, in countries like the U.S: ∙Mortality in children under 10 fell from 25% to less than 0.5%. ∙Male survival from age 10 - 65 increased from ~40% to 87%. ∙Life expectancy at age 65 increased from ~10 years to ~19 years.

Body Temperature

1. Forget *"cold blooded"* and *"warm blooded"* Replace with precise, physiological terms describing 1. *Heat Source* a. *Ectotherm* ∙Main *heat source* is the external *environment* ∙From the Greek ecto meaning "outside" b. *Endotherm* ∙Main *heat source* is internal *metabolic reactions* ∙From the Greek endo meaning "inside" 2. *Temperature Regulation*: a. *Poikilotherm* ∙Temperature *regulated* primarily by *environment* ∙From the Greek poikilo meaning "variable" b. *Homeotherm* ∙Temperature *regulated* primarily *metabolically* ∙(From the Greek homeo meaning "constant")

*Gnasthostomata/Hinged Jaws* (Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. Gnathostomata includes: ∙*Chondrichthyes* (sharks, skates and rays) ∙*Actinopterygii* (ray-finned fishes) ∙*Sarcopterygii* (lobe-finned fishes and tetrapods) 2. In fish, the cartilaginous pharyngeal gill arches bear *gills*. In tetrapods, gill arches became the *bones of a hinged jaw*. 3. Mammals took things a step further. Several of those jaw bones evolved into the bones of the mammalian inner ear.

*Hagfishes* (Myxini (Hyperotriti), Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. Hagfishes are *benthic (bottom-dwelling)*, eel-like animals: ∙The *skeleton is cartilaginous*. ∙Dorsal support provided by *notochord*. ∙Vertebrae are absent. ∙Cranium is cartilaginous and rudimentary. ∙*Small, conical eye spots* unchanged for 500 milliion years ∙Diet: *carrion (dead animals*) and small invertebrates 2. Hagfish are famous for a *remarkable defense mechanism*, which gives them their other nickname, "slime eels".

Algal Blooms

1. High levels of N and P cause *eutrophication*(excessive richness of nutrients in a lake or other body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life from lack of oxygen). 2. Ecosystem is disrupted as phytoplankton and cyanobacteria ("algae") *reproduce very quickly* with added N and P (from fertilizers) nutrients compared to other organisms. 3. Algal blooms: ∙*Deplete aqueous oxygen* ∙Promote overgrowth of *anaerobic bacteria* that often pathogenic ∙Can produce dangerous toxins (cyanobacteria) ∙*Magnify* the effects of *pollutants* ∙Threaten human and other animal health 4. Citizens in affected areas can take necessary steps to control: ∙Product content of nitrogen and phosphorus ∙*Effluent* and *runoff* Many bodies of water have been restored to better condition. 5. However, nutrient pollution is still a major environmental concern.

Random Distribution

1. If members of a population exhibit random dispersion, it means that there are no strong intraspecific factors controlling their distance from each other. 2. Relative locations are determined by chance. Example: *wind-dispersed plants*

*Caecilians* (Amphibia, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. If you didn't notice the mouth, you might think it was a huge worm. 2. Caecilians are tropical amphibians that have lost their legs and taken up a semi-fossorial existence.

*Circulatory System: Open and Closed*

1. In a *closed circulatory system*, a heart pumps *blood* enclosed at all times within vessels of different size and wall thickness. 2. In an *open circulatory system* a heart pumps *hemolymph*(insect blood) into a *hemocoel* body cavity where it sloshes around and bathes tissues and organs in dissolved nutrients and gases.

*The End*: Cloaca (Vertebrate Characteristics)

1. In many species, both the *excretory system* and the *reproductive tract* join the intestine near its end. 2. In this arrangement, the posterior exit provides egress for: ∙Nitrogenous/excretory waste ∙Reproductive products (eggs or sperm) ∙Fecal waste 3. This multi-purpose exit is is known as a *cloaca*. (Cloaca (Latin) translates as "sewer".) 4. Cloacae are found in: ∙Many invertebrates ∙Most fish ∙Most amphibians ∙All reptiles and birds ∙Monotreme mammals (platypus, echidna)

Coelom (Vertebrate Characteristics)

1. In vertebrates, the coelom forms the: ∙*Pericardium* surrounding the heart ∙*Peritoneum* surrounding the viscera 2. In tetrapods, it also forms the *pleura* surrounding the lungs

*Insects* (Hexapoda, *Pancrustacea*, Arthropoda, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. Insects (Hexapoda) have chewing mouthparts called *mandibles.* 2. There are more than 900,000 described species. Beetles alone number more than 350,000 species Body consists of a: ∙*Head* ∙*Thorax* ∙*Abdomen* ∙*Six (three pairs) of thoracic walking legs* ∙Two to four *wings *attached to the thorax ∙Some derived insect taxa have lost their wings 3. A biologist who studies insects is an *entomologist.*

Ecological Interactions Drive *Coevolution*

1. Interacting species *coevolve* in response to each other's activities. Each type of interaction will yield a different type of coevolutionary result. 2. Garter snakes eat salamanders which have poison glands. So the salamanders that are most toxic, are the ones that survive. So now the salamanders are so toxic that no other species can eat them.

*Thermoregulation* (Regulation vs. Conformity)

1. Interaction between an organism and its temperature environment affects ∙Its metabolic rate ∙Its species' geographical distribution 2. *Heat Source terms*: ∙*Ectotherm* - main *heat source* is the external *environment* ∙*Endotherm* - main *heat source* is internal *metabolic reactions* 3. *Temperature Regulation terms*: ∙*Poikilotherm* - temperature *regulated* primarily by *environment* (from the Greek poikilo meaning "variable") ∙*Homeotherm* - temperature *regulated* primarily by *metabolism* (from the Greek homeo meaning "constant")

Ecology

1. Is the study of: ∙Interactions of organisms with each other ∙Interactions of organisms with their environment 2. Ecology is the study of the various levels of *ecosystems*. 3. Ecology provides information to better understand the world around us. 4. This information can help us: ∙Improve/repair our environment ∙Manage our natural resources ∙Protect human health

Land and Water Hemispheres

1. Large-scale, global factors can affect local climate. 2. The Northern and Southern Hemispheres are very different in terms of water vs. landmass surface coverage. 3. This creates very different climates in the two hemispheres. 4. *Continental land mass vs. water mass.* ∙Ocean and lakes cover: -81% of southern hemisphere -61% of northern hemisphere 5. *Proximity to the ocean* vInland areas and coastal areas differ significantly in overall annual temperature, humidity, and wind patterns.

Survivorship Curves

1. Life table data can be plotted to yield an age-specific *survivorship curve.* Three idealized curves represent common survivorship patterns. ∙*Type I*- low risk of juvenile death likelihood of death increases with advancing age (human, lion) ∙*Type II*- Constant risk of death at all life stages (field mouse) ∙*Type III*-High risk of juvenile death and long adult life expectancy (for its species) (Sequoia tree, grouper, lobster)

*Crustaceans* (*Pancrustacea*, Arthropoda, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. Like insects, crustaceans have *mandibles.* 2. This diverse group includes *crabs, shrimp, lobsters, barnacles, isopods, amphipods, mantis shrimp* and a host of others to the tune of 67,000 species. ∙The chitinous exoskeleton is fortified with CaCO3 ∙Most are marine, but many live in freshwater or are terrestrial.

*Lophotrochzoa* (Protostomia, Bilateria, Eumetazoa)

1. Like other protostomes *lophotrochozoans* are characterized by (symplesiomorphies): ∙Mouth derived from blastopore ∙Bilateral symmetry ∙Triploblasty ∙Spiral, determinate cleavage ∙Schizocoely 2. Major Taxa Includes: ∙*Platyhelminthes* (true flatworms) ∙*Syndermata* (rotifers and acanthocephalans) ∙*Lophophorates* (brachiopods, phoronids, bryzoans) ∙*Nemertea* (ribbon worms) ∙*Annelida* (segmented worms) ∙*Mollusca* (clams, snails, octopus, squid, etc.)

*Sunlight* (Abiotic Factors and Organic Evolution)

1. Living organisms are profoundly affected by sunlight: ∙Intensity ∙Daily duration ∙Angle of incidence (seasonal changes) 2. Natural selection is driven by *competition for light* in many *terrestrial plant communities*. 3. *Aquatic community composition* varies with depth, in response to natural selection resulting in *different species having different light requirements and tolerances*.

*The Mammals* (Synapsida, Amniota, Reptiliomorpha, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. Mammals were the first vertebrates toadaptively radiate into a wide diversity of terrestrial habitats. 2. Mammalian synapomorphies: ∙*Endothermic homeotherms* ∙*Four-chambered heart* ∙*Mammary glands* ∙*Muscular lips* for suckling (marsupials and eutherians) ∙*Hair* (grows between epidermal homolog of reptilian scutes/scales) ∙*Anucleate red blood cells* ∙Muscular *diaphragm* separates thorax and abdomen ∙Ancestral jaw bones evolved to form inner ear bones ∙Jaw musculature increased in size and complexity ∙Bony plate (*hard and soft palates*) separatesthe mouth and nasal cavities -Allows animal to breathe with food in its mouth -Allows young to breathe while suckling 2. The flat, muscular *diaphragm* separates the trunk into *thorax* and *abdomen*. 3. The diaphragm contraction and relaxation inflates and deflates the lungs.

Boom and Bust Cycles

1. Many species undergo seasonal *"boom and bust" cycles* occurring with seasonal climate changes. 2. The effects of density-dependent factors are not always immediately apparent.In many cases, there is a "time lag" between a factor's effect and the resulting change in population density. 3. When climate changes affect population density of a prey species, the numbers of its predators generally follow after a time lag.

*Marsupialia* (Mammalia, Synapsida, Amniota, Reptiliomorpha, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. Marsupial mammals: ∙Are born at an extremely altricial stage of development ∙Fetus climbs to the mother's *marsupium* (pouch) and crawls in. ∙Baby latches onto a teat, and completes development in the marsupium. ∙This can take many weeks. 2. Examples: *kangaroos, koala, wombat*, ~ 250 others 3. In marsupials and eutherians: ∙*Spine undulates dorsoventrally* during locomotion.∙(In all other vertebrates, spine undulates laterally.) ∙*Leg joints are rotated under the body* ∙Skeleton, not muscles, support the body's weight -More energy efficient -Allows fast locomotion

*Salamanders and Newts* (Amphibia, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. Modern salamanders and newts most closely resemble the ancestral amphibian, which had a tail and five-digits on each limb. 2. Gilled, aquatic larvae lose their gills when they metamorphose into adults.

*Urochordata/The Tunicates* (Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. More than 3000 species of these soft-bodied, sessile creatures inhabit the world's oceans. 2. The free-swimming *tadpole larva* exhibits the chordate synapomorphies. 3 The adult looks nothing like the larva. 4. Both larva and adult are *filter feeders*, straining water through the porous pharynx.

*Nematomorpha/The Horsehair Worms* (Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. Mostly freshwater, but a few marine, these long, unsegmented worms are: ∙Free-living as adults ∙Parasites on arthropods as larvae 2. The large pseudocoelom houses a *hydrostatic skeleton*. Their whiplike motion is generated via contraction only of longitudinal muscles.

Facultative Mutualism (Protocooperation) (+, +)

1. NOT obligatory; both pop'ns benefit Ex. Clown fish and sea anemone

Major Environmental Disturbances (Abiotic Factors and Organic Evolution)

1. Natural disasters such as: ∙Fire (good sometimes) ∙Severe storms (hurricanes, tornadoes, etc.) ∙Volcanic activity ....can have major effects on ecosystems. 2. Such events can affect flora and fauna composition and diversity in many ways, even causing *extinctions*.

Adiabatic Cooling and Heating

1. Near earth's surface, gravity concentrates atmospheric molecules. At higher altitudes, molecules are less dense. Thus, lower altitudes have higher pressure than higher altitudes. 2. When air molecules move from earth's surface to higher altitude: ∙They expand (pressure decreases) ∙They undergo fewer collisions ∙This process results in cooler air temperatures, and is known as *adiabatic cooling.* 3. When air molecules move from higher altitude to earth's surface: ∙Then condense (pressure increases) ∙They undergo more collisions ∙This process results in warmer air temperatures, and is known as *adiabatic heating.*

Upwelling

1. Strong winds blowing from continents can push surface ocean water out to sea. 2. Deep, cold water from below rises up to replace it, a phenomenon known as *upwelling.* 3. Water and sediments at the bottom of the ocean are rich in nutrients. 4. *Upwelling brings these nutrients to the surface.* 5. The result is an increase in: ∙Algae, plant, and phytoplankton biomass ∙Marine consumer biomass ∙Terrestrial (coastal) consumer biomass ∙Biodiversity 6. Downside: upwelling can push planktonic larvae out to open ocean, away from their productive "nursery" coastal habitat. 7. *Coastal upwelling regions occupy about 1% of the ocean surface and provide ~50% of world's fisheries catch*

Primary and Secondary Succession

1. Succession can be ∙*Primary (starting from scratch) ∙*Secondary* (replacing a damaged system) 2. Human activity has driven a lot of succession since the Industrial Revolution. 3. Can ecosystems always recover?

The Greenhouse Effect

1. Not to be confused with global warming, the Greenhouse Effectis a natural phenomenon that allows life on earth to exist. 2. Greenhouse gases: ∙H2O vapor ∙CO2 ∙CH4 ∙N2O ∙O3 ∙Hydrofluorocarbons (anthropogenic) 3. Greenhouse gas molecules absorb and reflect solar energy: ∙Arriving from the sun ∙Being reflected from Earth's surface 4. The warming effect is similar to that of the glass panes in a greenhouse: ∙*Higher concentration* of greenhouse gases --> *higher temperatures* ∙*Lower concentration* of greenhouse gases --> *lower temperatures* 5. *Oxygen* and *nitrogen*, the two most abundant atmospheric gases, are *not greenhouse gases*. 4. Because greenhouse gases comprise such a small fraction of the atmosphere, a small change in their concentration can have significant effect. 5. If you were born after 1977, you have not experienced a colder-than-average year. 6. February 1985 was the last month with below average temperatures. 7. In the 20th century... ∙The average global temperature anomaly was zero. HOWEVER... ∙Most colder-than-average years occurred in the first 50 years. ∙Most warmer-than-average years occurred in the last 50 years. 8. February 2019 was the 34th consecutive February with temperatures above the 20th century average. 9. December 2018 marked more than 400 consecutive months of temperatures above the 20th century average.

Ocean Currents

1. Ocean currents move: ∙Warm water from the equator towards the poles ∙Cold water from the poles towards the equator 2. The Coriolis Effect generates a *gyre* in each major ocean: ∙*Clockwise* in the *northern hemisphere* ∙*Counterclockwise* in the *southern hemisphere* 3. Currents are generated and affected by: ∙Tides (gravitational pull of moon and sun on earth) ∙Wind ∙Thermohaline circulation ∙Ocean floor topography ∙Coriolis Effect 4. *Surface currents*: ∙Comprise the *upper 10%* of water mass ∙Are generated primarily by wind and tides 5. *Deep currents*: ∙Comprise the* lower 90%* of water mass ∙Are generated primarily by thermohaline circulation

ENSO: El Niño, La Niña

1. Perhaps the most famous upwellings is the El Niño-Southern Oscillation (ENSO), and its counterpart, La Niña which normally occur every 10-12 years. 2. These events can affect weather patterns thousands of miles away. 3. El Niño conditions usually commence in late December("El Niño" = Christ Child), and may last for several months. 4. El Niño: ∙Reduced trade winds ∙Reduced upwelling ∙Increased precipitation outside the tropics ∙Drought in South America, SE Asia, Australia ∙Loss of nutrients disrupts food chains 5. Small, fragile ecosystems are most strongly affected by El Niño, perhaps none more so than The Galapagos Islands. 6. Under normal conditions, the *Cromwell Countercurrent* on the west side of the archipelago brings up cold, nutrient-rich water. 7. Phytoplankton blooms, providing plentiful food for animals. 8. *The Cromwell Countercurrent upwelling has allowed this ecosystem to become a hotspot of evolution and biodiversity.* 9. But in an El Niño cycle... ∙Upwelling is reduced ∙Precipitation increases ∙Increased terrestrial plant growth, production ∙Marine nutrients diminish ∙Phytoplankton and algae die ∙Die-offs move up the food chain 10. As El Niño events become: ∙More frequent ∙More intense ...researchers are trying to determine whether Galapagos ecosystems can continue to recover and maintain their unique character.

Population Growth

1. Populations are not always stable in size. 2. Births, deaths, immigration, and emigration do not necessarily generate a state of equilibrium. 3. Three different mathematical models can be used to describe the growth of populations: ∙Arithmetic growth ∙Exponential ∙(Geometric) growth logistic growth

Neutralism (0,0)

1. Populations do not affect one another ∙Two populations exist in the same ecosystem ∙Neither affects the evolutionary fitness of the other Ex. Shrimp and a camel

Competition (-,-)

1. Populations inhibit one another Ex. Brown vs. Green Anole

Exponential vs. Geometric Growth

1. Populations undergoing exponential or geometric growth both exhibit a J-shaped growth curve. 2. But there is a difference between them. ∙The *exponential growth model* applies to species that *reproduce throughout the year*. ∙The *geometric growth model* applies to species that *breed* only over a *limited time* during the year.

Predation (+, -)

1. Predator (A) kills & consumes prey (B) 2. *Herbivorous* predators kill and consume entire plants or seeds. 3. *Mesopredators* consume herbivores and are generally small 4. *Top carnivores* consume herbivores and mesopredators and are generally large.

Cephalopod Camera Eye

1. Recent research indicates cephalopods can distinguish colors with a mechanism different from that of any other animal. 2. Their weirdly shaped pupils may allow them to detect color and mimic the colors of their background 3. They see color differently since they have an unusual pupil that is U-shaped, W-shaped, or dumbbell-shaped 4. They accentuate chromatic aberration and minimize other sources of vision error

Sunlight Quality and Quantity

1. Terrestrial sunlight's: ∙Spectral distribution (quality) ∙Irradiance (quantity) 2. Depend on ∙Insolation angle of incidence ∙Environmental conditions 3. Because of Earth's curvature, insolation varies with latitude. Latitudes away from the equator receive *oblique* insolation, which spreads sunlight over a larger area. 4. Thus, *northern and southern latitudes receive less energy per unit area than equatorial latitudes.* 5. The difference varies over the course of the year.

*Sarcopterygii/The Lobe-finned Fishes* (Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. The lobe-finned fish are the closest relatives of tetrapods: ∙Well-developed bony skeleton with strong fin bones. ∙Fleshy, lobed fins resemble and move like tetrapod limbs. ∙Lungs are homologous to tetrapod lungs. ∙Gills are also present and used to breathe under water. 2. Ancient sarcopterygiians evolved adaptations that made terrestrial locomotion possible. 3. They probably looked something like *Tiktaalik*, an ancient lobe fin that had all the skeletal and respiratory equipment to make that first move onto land.

*The Amniotes* (Reptiliomorpha, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. Reptiliomorpha includes all animals that encase their young in an *amniotic egg*: ∙*"Anapsida"* turtles ∙*Diapsida* reptiles (including birds) ∙*Synapsida* - mammals 2. Cranial morphology can reveal common ancestry: ∙*Anapsida* - No temporal opening behind the eye orbits -Ex. Turtles and tortoises ∙*Synapsida* - Single temporal opening behind the eye orbits -Ex. Mammals ∙*Diapsida* - Two temporal openings behind the eye orbits -Ex. Tuataras, lizards, snakes, crocodilians, birds 3. An *egg* consists of ∙An *ovum* ∙Nutritive *yolk* ∙Protective *envelope* 4. In fish and amphibian eggs: ∙Yolk is stored in the developing embryo's gut ∙The embryo is enclosed in a simple shell or gelatinous capsule 4. Amniote reptiliomorphs enclose their young in an *amniotic egg*, which allows true independence of a watery environment. 5. From inside to outside, the amniotic egg components are ∙Gas-permeable, *desiccation-resistant shell* ∙*Outer membrane* lining the inside of the shell ∙*Inner membrane* enclosing the *albumin* proteinaceous albumin surrounding *fluid-filled membranes*: -*Chorion* - encases the internal membranes -*Amnion* - encloses the growing embryo -*Allantois* - collects embryo waste products -*Yolk sac* - contains nutritive yolk connected to embryo gut 6. The amniotic egg necessitates *internal fertilization*. Ovum and sperm must fuse before the shell is made. 7. The *eutherian (placental) mammal* amniotic egg has undergone evolutionary modification: ∙*Amnion* surrounds the embryo ∙*Yolk sac* and *allantois* form the *umbilical cord* ∙*Chorion* -Surrounds the other membranes -Fuses with the uterine wall -Forms nutrient/waste removal bridge between mother and offspring

Whittaker Biome System

1. Robert Whittaker based his biome classifications on *temperature* and *precipitation.* 2. He matched vegetation type to regional climate to create a triangular figure within which all biomes fall. 3. Whittaker terms: ∙*Physiognomy*: characteristics or appearance of ecological communities or species ∙*Biome*: grouping of terrestrial ecosystems on a given continent that is similar in vegetation structure, physiognomy, environmental features, and animal community characteristics. ∙*Formation*: a major type of plant community on a given continent ∙*Biome type*: grouping of *convergent* biomes or formations from different continents, defined by physiognomy (Mediterranean is similar to chaparral in California, but they have completely different species) ∙*Formation type*: a grouping of *convergent* formations 4. In the Whittaker system... ∙*Tropical/Equatorial* climate zones have: -Mean annual temperatures of 20° - 30°C -Mean annual precipitation of 0 - 400+ cm ∙*Temperate* climate zones have: -Mean annual temperatures of 5° - 20°C -Mean annual precipitation of 0 - 300+ cm ∙*Boreal* and *Polar* climate zones have: -Mean annual temperatures of < 5°C -Mean annual precipitation < 200 cm

*Rotifers* (Syndermata, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. Rotifers are: ∙Microscopic ∙Adorable ∙*Pseudocoelomate* ∙Aquatic (marine, fresh water, brackish) ∙Almost anywhere in nature where there's a *thin film of water.* 2. Rotifers can thrive in: ∙Lake and pond sediments ∙Stream and river sediment ∙Moist areas on mosses and lichens ∙Rain puddles, ∙Wet leaf litter ∙Fruiting bodies of fungi ∙Sewage treatment tanks 3. The common name, *"wheel animalcules"*, comes from the crown of cilia on the head. 4. The corona of beating cilia resembles spinning wheels. The water current generated by the coronia carries food particles to the mouth.

*Holothuroidea/Sea Cucumbers* (Echinodermata, Deuterostomia, Bilateria, Eumetazoa)

1. Sea cucumbers are pentaradially symmetrical, but lie on one side so that oral and aboral surfaces are positioned as anterior and posterior. 2. Sea cukes are characterized by: ∙Complete gut with a mouth and anus. ∙Tube feet that help transfer food to the mouth. ∙Unique and somewhat gross defense mechanism. 3. And then there's Our Friend the Sea Pig.

Aposematism (warning coloration)

1. Sends the message that an animal is distasteful or toxic. 2. An experienced predator will recognize that this particular animal is: ∙Potentially dangerous ∙Not worth the risk ...and seek food elsewhere. 3. Know the difference: ∙Poisonous/toxic - harmful when eaten or touched ∙Venomous - delivers toxin with an apparatus such as a fang or stinger

Solar Energy

1. Solar *Irradiance*: -Is the flux of radiant solar energy per unit area -An instantaneous measurement of solar power per unit area -Usually expressed as *kilowatts/m²* 2. *Insolation* is: ∙Cumulative solar energy measured over per unit area ∙Measured for a defined period of time (e.g., annual, monthly, daily) ∙Usually expressed as *kilowatt hours/m²* ∙(A kilowatt hour = 1,000 watts/hour) 3. Sunlight reaching Earth's surface ranges from *~250nm (ultraviolet)* to *~1500nm (infrared).* 4. Solar irradiance is most intense when the sun is directly overhead in a cloudless sky, peaking near 540nm ("green").

*Ecological Succession* (Diversity Changes)

1. Species interactions can drive change in species diversity over time. 2. *Ecological Succession* is the process of change in community structure of an ecosystem over time. 3. It generally begins with some type of disturbance: ∙Wildfire ∙Volcanic eruption ∙Anthropogenic ecosystem disruption ... and can take decades to hundreds of years to reach a *climax community* state.

*Squamata* (Diapsids, Amniota, Reptiliomorpha, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. Squamata includes more than 10,000 species of (lizards and snakes.* 2. Squamate characteristics: ∙*Ectothermic poikilotherms( ∙*Three-chambered heart* ∙Scaly, keratinous skin ∙Overlapping, *epidermal scales* (do not shed) ∙Molting of skin with growth ∙*Movable quadrate bones* allowing the maxilla to move relative to the neurocranium (brain case) ∙Tremendous variability in size, morphology, and natural history

Cephalochordata/The Lancelets (Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. The marine, eel-like *lancelets* exhibit all the chordate characteristics. 2. There are only 32 extant species of these *fossorial filter feeders.* 3. The lancelet burrows into the substrate, tail down, and protrudes its head into the water to feed.

Albedo

1. Terrestrial surfaces do not all reflect solar energy to the same degree. 2. *Albedo* is *the percentage of solar radiation striking a surface that is reflected back by that surface.* 3. Light colored surfaces have higher albedo than dark colored surfaces. Surface textures and humidity can affect albedo. 4. Albedo magnifies the effects of unequal insolation on a *global level*. ∙*Equator*: Low albedo of ocean and forests ∙*Poles*: High albedo of ice 5. Albedo also can have strong effects at a *local level*: ∙Low albedo of concrete and asphalt increase heat. ∙Unlike on soil or vegetated areas, surface water evaporates rapidly. ∙Unlike on soil or vegetated areas, surface water cannot be absorbed. ∙This contributes to lower atmospheric humidity over concrete/asphalt. ∙Regions with large areas of concrete/asphalt receive lower rainfall.

Arithmetic Growth

1. The *Arithmetic Model* describes a population growth rate that is *unaffected by population size*. 2. A population undergoing *arithmetic growth* increases in size by the same increment over each time interval. 3. This is described by the equation *Nt+1 = Nt + B - D* where: Nt = population size at time t B = number of births from time (t) to time (t+1) D = number of deaths from time (t) to time (t+1) (B - D) = C = net change in population size 4. Because immigration (I) is numerically equivalent to births and emigration (E) is numerically equivalent to deaths, the model can be modified to include them: *Nt+1 = Nt + (B + I) - (D + E)* 5. Although the model assumes that deaths and births are independent of population size, in reality, as population size increases... ∙Absolute number of ∙Births and deaths increases ∙Birth and death rates per individual remain the same 6. You don't see it very often in real populations

Competitive Exclusion

1. The *Competitive Exclusion Principle (Gause's Law)*: *In a stable environment, two species cannot coexist if they occupy exactly the same ecological niche.* 2. Species competing for the same resources must evolutionarily adapt to exploit different resources. 3. This leads to *resource partitioning*: dividing a common resource so that each competing species uses only a portion of that resource.

Earth's. Atmosphere

1. The *atmosphere* is the layer of gases ("air") surrounding earth and retained by Earth's gravity. 2. The atmosphere ∙Retains heat ∙Reduces temperature extremes ∙Generates pressure needed for liquid water to form on earth ∙Absorbs harmful short-wavelength solar and cosmic radiation 4. Air composition, temperature, and pressure vary with altitude, but its essential composition (by volume) is -*Primary gases*: 78% Nitrogen, 21% Oxygen, 1% Argon -*Greenhouse gases*: 0.04% Carbon dioxide, 0.4 - 1.0% Water vapor, Trace amounts of other gases (not all are greenhouse gases)

The Biosphere (Ecological Hierarchy)

1. The *biosphere* comprises all of earth's ecosystems, considered collectively. 2. Both proximate and distant ecosystems are connected by: ∙Wind movement ∙Water movement ∙Migration of organisms ∙Energy exchanges 3. *The biosphere is the earth's thin outer layer of life and the abiotic components supporting it.*

The Doldrums

1. The *doldrums (equatorial calms)*: ∙The ITCZ extends about 5° to the north and south of the equator. ∙Here, *northern and southern trades collide, neutralizing each other*. ∙Intense insolation causes air to rise with little lateral movement. ∙There is *often very little wind in the ITCZ*. ∙Sailing ships can be stuck there for weeks. ∙The region is named for the personal sluggishness known as "the doldrums".

Dominant Species

1. The *dominant species* in a community are the most numerous or have the *highest total biomass* in that community. 2. They tend to exert a strong influence on community structure and dynamics. 3. *Example*: Sugar Maples typically form dense stands that affects oil nutrient composition and shade habitat.This affects which other plant species (and hence, animal species) can live in the forest. 4. *Why does a species become dominant?* ∙Better at competing for limited resources ∙Better at avoiding predation or pathogens (Why are exotic invasive species so invasive? Since no endemic species can stop or predate the invasive species)

The Ecosystem (Ecological Hierarchy)

1. The *ecosystem* comprises the interactions of the community with abiotic factors in a given area. 2. *Biogeochemical* cycles describe the movement of energy and matter between living and non-living components of the ecosystem: ∙Water Cycle ∙Carbon Cycle ∙Nitrogen Cycle ∙Phosphorus Cycle etc. 3. Ecosystem boundaries are often not distinct.

Fundamental vs. Realized Niche

1. The *fundamental niche* is the niche that a species potentially could occupy, given its physiology and natural history. 2. Because of competition and other limitations, few species actually fill their fundamental niche. 3. Instead, they occupy a subset of the fundamental niche, the *realized niche.* 4. Predators or competition can prevent an organism from fulfilling their fundamental niche.

The Individual/Organismal (Ecological Hierarchy)

1. The *individual* is the most fundamental unit of ecology. An individual: ∙Acquires nutrients and energy ∙Produces waste ∙Is separated from the environment by a membrane boundary 2. A group of genetically similar individuals capable of interbreeding to produce fertile, viable offspring comprises a *biological species*.

Unequal Solar Heating Creates Climate Zones

1. The *polar* regions lie above 60°N and S 2. The *temperate* regions lie between: ∙30°N and 60°N in the Northern Hemisphere ∙30°S and 60°S in the Southern Hemisphere. 3. The *subtropics* lie between: ∙Tropic of Cancer (23.5°N) and 30°N ∙Tropic of Capricorn (23.5°S) and 30°S 4. The *tropics* lie between the ∙*Tropic of Cancer (23.5°N)* ∙*Tropic of Capricorn (23.5°S)*

*Set Point* (Homeostasis)

1. The *set point* of a controlled variable is the level of that variable required for normal function. 2. *Feedback* from the controlled variable tells the body whether the variable needs to be regulated in some way. 3. Example: A horse's normal body temperature range is ~37.5 - 38.5°C. If the horse's body temperature exceeds normal ∙Skin and brain receptors inform the brain. ∙Brain informs cooling effectors -Sweat glands activate -Blood vessels in skin and extremities dilate

The Abiotic Earth

1. The *sun* is the primary source of earth's energy. It drives and generates climate. 2. Global variations in topography interact with wind, water, and other abiotic factors to create different types of *soils*. 3. *Global variations in climate and geology lead to diversity of biological systems*. 4. *Climate* and *soils* are the foundations of the biosphere.

*Mollusca* (Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. The 85,000 species of mollusks include such familiar animals as *snails, slugs, clams, squid, and octopods.* 2. They are second only to Arthropods in their vast diversity. About 23% of all (described) marine organisms are mollusks! 3. All mollusks: ∙Are *coelomate* ∙Have a *soft, unsegmented body* ∙In primitive condition, an *external shell* ∙Live in aquatic or damp habitats 4. Synapomorphies: ∙Coelom reduced to a *gonocoel* surrounding the gonads. ∙Primary body cavity is the haemocoel. ∙Open circulatory system (except cephalopods, aka squids and octopus) ∙Rasplike *radula *feeding structure. ∙Large, complex *metnephridia* (kidnet) comprise the excretory system. ∙A *trochophore larva.* 5. In more derived forms, the trochophore develops into a more complex *veliger* larva. 6. The major molluscan clades are: ∙*Polyplacophora* (chitons) ∙*Scaphopoda* (tusk shells) ∙*Bivalvia* (clams, mussels, scallops, etc.) ∙*Gastropoda* (snails and slugs) ∙*Cephalopoda* (Nautilus, squid (="cuttlefish"), octopods) 7. Gastropods and Cephalopods are the only mollusks with relatively large brains and complex behaviors.

Human Population Growth Rate

1. The U.S. population has continually increased since its inception. 2. In 1910, the growth rate began to decline. Based on these data, (Pearl and Reed* (1920) predicted U.S. population size would reach a maximum of *197 million*. 3. But by 2018, the U.S. population was *327.2 million*. 4. Global human population has shown a similar trend.

*Arthropoda/The Joint-legged Animals* (Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. The arthropods comprise 5 - 10 million species, rivaled only by nematodes for sheer numbers. 2. Arthropods inhabit every conceivable environment, from *open ocean*, to the *bodies of fungi, plants, and animals*, including your eyelash follicles. 3. Our understanding of arthropod evolutionary relationships has undergone major revision over the past decade or so. 4. Four major clades are likely monophyletic: ∙*Chelicerata* ∙*Myriapoda* ∙*Crustacea* ∙*Hexapoda* But the evolutionary relationships among these four taxa remain uncertain. 5. Two Major Hypotheses: ∙*Paradoxopoda* (supported by morphological characters) ∙*Mandibulata* (supported by mtDNA data) 6. Arthropods are characterized by: ∙*Jointed limbs* ∙A tough, articulated chitinous *exoskeleton* ∙A waxy covering on the cuticle (protection against desiccation) ∙Exoskeleton fortified with *CaCO3* in marine species ∙*Tagmosis* (head, thorax, abdomen fusion) ∙An *open circulatory system* ∙A *haemocoel* as main body cavity ∙A coelom reduced to a *gonocoel* and *pericardium*. 7. Thin muscles anchored to the inside of the rigid exoskeletal plates create a *lever system.* Very small muscle contractions will move the plates (and the animal) quickly, with little energy expenditure. 8. The arthropod *compound eye* is composed of *ommatidia*, each of which provides a small unit of the entire field of vision. 9. The number of ommatidia per eye varies among species. The more ommatidia, the more finely resolved the image. 10. *Dragonflies* have more ommatidia/unit area than any other arthropod. These aerial predators have evolved high visual acuity that allows them to localize and capture small, flying prey in mid-flight. 11. Different arthropod species undergo different degrees of development and metamorphosis. 12. These can be categorized as ∙*Simple* metamorphosis ∙*Complete* metamorphosis ∙*Mixed* metamorphosis

Atmospheric Regions

1. The atmosphere can be divided into two main regions: ∙Troposphere*: -From earth's surface to ~12km ∙*Stratosphere*: -From ~12km to 50-55km above earth's surface 2. The *tropopause* is the *interface between trophosphere and stratosphere.* 3. It is the altitude at which air ceases cooling with height, and is almost completely devoid of water vapor.

Chelicerata (Arthropoda, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. The chelicerates are united by both molecular and morphological similarity. 2. Chelicerata includes spiders, scorpions, mites, ticks, horseshoe crabs, and more. 3. All chelicerates have pinching/stabbing mouthparts known as *chelicerae.* 4. Depending on species, these can be one of three basic types: (A) *Jacknife* (B) *Scissor* (C) *Three-segmented* ...each adapted for a specific feeding natural history.

Internal and External Environments

1. The conditions experienced by cells and tissues include: ∙Temperature ∙pH ∙Water content ∙Ion concentrations ∙Etc. 2. Most of a multicellular organism's cells are surrounded by other cells, and do not directly contact the *external environment.* 3. Most experience only the internal environment

The Anthropocene Extinction

1. The current extinction rate has been estimated at 24 - 150 species lost per day. This is 1,000 times higher than "normal" extinction rate. 2. The current extinction rate is similar to that of previous mass extinctions. 3. This extinction is anthropogenic, and being caused by: ∙*H*abitat loss ∙*I*nvasive exotic species ∙*P*ollution ∙*P*opulation Explosion ∙*O*verexploitation 4. And the most recent threat, *anthropogenic climate change*: Humanity will not be able to stop this process without clearly understanding how ecosystems work.

Craniata/Animals with Skulls (Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. The defining synapomorphy uniting all Craniates is the *cranium*, a bony skull encasing the brain. 2. Craniates can be divided into: ∙*Myxini (Hyperotriti)* (hagfishes) ∙Vertebrata -*Petromyzontida* (Hyperoartia) (lampreys) -*Gnathostomata* (jawed vertebrates) 3. Extant Craniate taxa exhibit a *progression of derived characters* that reflects the *sequence in which these traits evolved.* a. *Hagfishes* ∙Evolution of a simple *cranium* b. *Lampreys* ∙Evolution of a *vertebral column* c. *Bony Fishes* ∙Evolution of a *hinged jaw* derived from gill arches ∙Evolution of a *mineralized (bone) skeleton* d. *Lobe-finned Fishes* ∙Evolution of (four fleshy, muscular limbs* e. *Lungfishes* ∙Evolution of *lungs* (lung fishes) f. *Tetrapods* ∙Evolution of *five digits* at the end of each limb f. *Amniotes* ∙Evolution of *amniotic egg* ∙Evolution of *leathery skin* g. *Mammals, Birds* ∙Convergent evolution of: ∙*Homeothermy* ∙*Insulating skin derivatives*

Holdridge Life Zones

1. The earliest biome concept was published by Leslie Holdridge in 1947. 2. The life zone system *assumption*: If climate is known, soil and vegetation can be predicted and mapped. 3. Three axes: ∙*Precipitation* (log annual) ∙*Biotemperature* (all T° above freezing; log mean annual) ∙*Potential evapotranspiration (PET) : mean total annual precipitation* (ratio)

Perihelion and Aphelion

1. The earth is not always equidistant from the sun ∙*Perihelion* ~ January 3 - earth is closest to the sun ~ 147,500,000 km between earth and sun ∙*Aphelion* ~ July 4 - earth is farthest from the sun ~ 152,500,000 km between earth and sun

Equinoxes and Solstices

1. The earth is tilted *23.5°* on its axis, defining the tropics. 2. Because of this tilt, insolation varies over the course of the year in each hemisphere. 3. Flora and fauna are profoundly affected by these changes. ∙*Equinoxes* - day and night are the same length (sun directly overhead) ∙*Solstices* - days when the sun reaches its highest or lowest point at noon (depending on hemisphere) (sun directly overhead) 4. *The Tilt of Earth's Axis is the Reason for the Seasons.*

Camera Eye and Photoreceptors (Vertebrate Characteristics)

1. The image-forming *camera eye* was a major evolutionary innovation: ∙*Cornea* is the outermost lens ∙*Aqueous chamber* provides nutrition, intraocular pressure ∙*Lens* changes focal distance ∙*Iris* controls pupil aperture ∙*Vitreous* chamber provides most of the intraocular pressure ∙*Retina* is the sensory layer 2. The vertebrate retina may have two types of photoreceptors: ∙*Rod photoreceptor*s confer high sensitivity to light (night vision) ∙Low image resolution ("grainy" picture) ∙No color information 3. *Cone photoreceptors* confer: ∙Relatively low sensitivity to light (day vision) ∙High image resolution (clear picture) ∙*Different classes of cones* absorb different λ of light ∙This allows color discrimination. 4. Recall that cephalopods also have a camera eye. The cephalopod and vertebrate camera eyes evolved independently. They are a product of convergent evolution.

Environmental Reparation and Improvement

1. The mid-20th century saw the rise of abnormal *algal blooms* in bays, rivers, streams, lakes, and other bodies of water. 2. *Ecological research* in the 1960s pinpointed; ∙The *reason*: excessive nitrogen and phosphorus in wastewater ∙The *source*: laundry detergent, fertilizer 3. *Wastewater* is any water that has been affected by human use: ∙Domestic ∙Industrial ∙Commercial ∙Agricultural ∙Surface runoff ∙Stormwater ∙Sewer inflow ∙Sewer infiltration

*Echinoidea/Sea Urchins and Sand Dollars* (Echinodermata, Deuterostomia, Bilateria, Eumetazoa)

1. The name derives from Greek echinos, meaning "spine". 2. Echinoids are characterized by: ∙Hard, calcium carbonate *test* (skeleton) ∙Ambulacral grooves running oral to aboral ∙Herbivory or carnivory, depending on species 3. The mouth bears a specialized, five-part chewing apparatus, *Aristotle's Lantern.* 4. Muscles inside the test move the plates, enabling the urchin to feed with the hard, calcareous external "teeth". 5. Some consider sea urchin gonads full of eggs to be a special delicacy. If you've eaten uni at a sushi bar, you can tell us your opinion.

Jet Streams

1. The physical processes that produce global air cells also produce *jet streams*. 2. The temperature gradient between polar air and warmer air from lower latitudes draws air towards the poles. 3. *Jet streams* are relatively shallow, narrow fast-moving air currents at various levels in the atmosphere. 4. Four global jet streams formed just below the tropopause have major impacts on global climate and weather. ∙Polar jet streams ∙Subtropical jet streams 5. Coriolis, geography and shifting temperatures create a complex, constantly changing pattern of *wind currents*.

Trophic Structure

1. The structure and dynamics of a community are largely determined by the feeding relationships among its species. 2. This is the community's trophic structure. 3. The transfer of energy: ∙From primary producers (photosynthetic organisms) ∙To primary (1°) consumers (feed on producers) ∙To secondary (2°) consumers (feed on 1o consumers) ∙To tertiary (3°) consumers (feed on 2° consumers) ∙To decomposers (feed on dead everyone else) ... is known as a food chain.

Organismal Ecology

1. The study of how an individual organism's morphology, physiology, and behavior allow it to meet the challenges posed by its environment. 2. *Homeostasis* is common to all living things. 3. *An organism's reproductive success (the keystone of natural selection) depends on its ability to maintain homeostasis in the face of environmental changes.*

The Ecological *Niche*

1. The sum of a species' use of the biotic and abiotic resources in its environment--as dictated by its evolutionary adaptations--is called that species' *ecological niche.* 2. The ecological niche includes that species: ∙Physical use of habitat ∙Range of tolerance to physical extremes (heat, salinity, pH, etc.) ∙Use of resources (food, space, etc.) ∙Circadian rhythm ∙Reproductive strategies and natural history ∙Interactions with biotic and abiotic environmental factors 3. Everything a species is and does determines its ecological niche, which can be considered its ecological position relative to other species in the same ecosystem.

Days of Greatest Irradiance

1. The sun is directly overhead only the *solstices* and *equinoxes* at high noon, and only at *specific latitudes*. ∙On the *Summer Solstice* (~ June 21) at the *Tropic of Cancer* (23.5° N) ∙On the *Winter Solstice* (~ Dec 21) at the *Tropic of Capricorn* (23.5° S) ∙On the *Vernal Equinox* (~ March 20) at the *equator* ∙On the *Autumnal Equinox* (~ Sept 22) at the *equator*

Agricultural Growth Zones

1. The tropics: ∙Receive the highest annual input of solar energy ∙Are the only place on earth where the sun ever shines directly overhead ∙This occurs on the *equinoxes*: -March 21 -September 21 2. Topography creates smaller climatic regions within the global zones.

Species Diversity

1. The variety of species found in an ecosystem comprise that ecosystem's *species diversity*. 2. Has two components: ∙*Species Richness*-the number of different species in the community ∙*Relative Abundance*- The proportion of the community represented by each species

*Cephalopoda* (Mollusca, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. There are about 100 species of cephalpods, including: ∙Nautilus species ∙Squids (a.k.a. "cuttlefish") ∙Octopods 2. Cephalopods: ∙Are *exclusively marine* ∙Are *fast-swimming predators* ∙Have a *shell* that is: -External in Nautilus -Internal in squids (forms the "cuttlebone") -Lost in octopods 3. The cephalopod *camera eye* is analogous to the vertebrate eye: ∙Forms a well-resolved image ∙Photoreceptors face into the vitreous ∙Which is the reverse of the vertebrate arrangement ∙Only one class of photoreceptor (suggests colorblindness). ∙However, recent research *indicates they can distinguish colors with a mechanism different from that of any other animal.* 4. Cephalopods are *intelligent!* 5. Many exhibit behaviors consistent with complex cognitive function and the capacity to solve problems.

*Acanthocephalans* (Syndermata, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. There are about 1000 known species of *Acanthocephalans*. 2. They are essentially *highly derived rotifers* specialized to *parasitize vertebrates*. 3. They range in size from 1mm to more than one meter! 4. Molecular analysis reveals their close relationship to rotifers. 5. Acanthocephalans have: ∙A spiny, eversible *proboscis* to grab the host gut wall ∙Secondarily lost mouth and intestine ∙This mirrors the reduction of organ systems seen in other *endoparasites*. 6. Acanthocephalans have a complex life cycle with both *intermediate* and *definitive hosts*.

*Ophiuroidea/The Brittle Stars & Basket Stars* (Echinodermata, Deuterostomia, Bilateria, Eumetazoa)

1. There are about 2000 described species of ophiuroids. (Greek ophis, meaning "serpent") 2. Brittle stars are characterized by: ∙Distinct central disk ∙Five long, snakelike arms radiating from disk ∙Relatively fast-movement ∙Detritivory/scavenging ∙Secondarily lost anus (dual purpose mouth, gross!) ∙Cilia-lined sacs (*bursae* on the oral side of the disk: -Perform gas exchange -Excrete nitrogenous waste 3. There is no functional excretory system.

*Crinoidea/The Sea Lilies* (Echinodermata, Deuterostomia, Bilateria, Eumetazoa)

1. There are about 600 described species of sea lilies. 2. They are: ∙*Benthic* (bottom dwelling) ∙Usually *sessile* (attached to the substrate) ∙Able to swim to change location ∙Suspension feeders (via ambulacral groove)

*Vertebrata/The Vertebrates Synapomorphies* (Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. There are about 70,000 species of vertebrates, most of them bony fishes. 2. All share these synapomorphies: ∙Highly developed *brain* ∙*Bony cranium* housing the brain ∙Articulated, dorsal *vertebral column* ∙Nerve cord protected inside vertebral column ∙*Bony skeleton* (primitive condition) ∙Well developed *epithelia* ∙Complex *camera eye* ∙Closed circulatory system with *multi-chambered heart* ∙Three types of *muscle tissue* ∙Well developed *endocrine system* 2. Vertebrates have three main body regions: ∙*Head* ∙*Trunk* ∙*Postanal tail* ∙(A *neck* comes later)

*Asteriodea/The Sea Stars* (Echinodermata, Deuterostomia, Bilateria, Eumetazoa)

1. There are about ~1800 described species of sea stars. 2. Asteroids are characterized by... ∙Distinct pentaradial symmetry ∙(Some species have many more than five arms (some up to 50!)) ∙Slow movement ∙Benthic life history ∙Predatory life history, feeding mostly on bivalves 3. Sea stars can regenerate an entire starfish from one ray, as long as part of the central disk is attached.

*Priapulida/The "Penis Worms" (Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. There are only 20 species in this group of marine predators, named for *Priapus*, the Greek god of fertility. 2. Penis worms: ∙Are *fossorial* (burrowing) ∙Prey on other soft, slow-moving invertebrates ∙Can withstand anoxic conditions high in H2S (muddy shoreline) ∙Employ the coelom as a *hydrostatic skeleton*. 3. Priapulids are *revealing new frontiers in evolutionary biology*! 4. Have a *Psuedocoelom*

*Onychophora/The Velvet Worms* (Parasitic Nematodes, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. These small, tropical predators are *semi-fossorial*, burrowing in leaf litter. 2. Velvet worms are characterized by: ∙Distinct metamerism ∙*Paired, chitinous appendages* on each segment ∙*Open circulatory system* ∙*Hemocoel* as main body cavity ∙Coelom reduced to a *gonocoel* (around gonads) and *pericardium* (around hearts). 3. Velvet worms give birth to and care for *live young.*

*Centipedes and Millipedes* (*Myriapoda*, Arthropoda, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. These terrestrial arthropods are named for their many walking legs. 2. *Chilopoda - The Centipedes* ∙Two (one pair) walking legs per segment ∙Body is dorsoventrally flattened in cross-section ∙Terrestrial carnivores ∙Scary as %$^* 3. *Diplopoda - The Millipedes* ∙Four (two pairs) of walking legs per segment ∙Body is round in cross section ∙Entirely herbivorous and detritivorous

*Syndermata* (Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. This clade includes ∙*Rotifers* ("wheel animalcules") ∙*Acanthocephalans* (parasitic "spiny-headed worms"). 2. There are more than 3000 species, exhibiting a wide range of natural histories from free living pond dwellers to parasitic creepies.

The Great Ocean Conveyor Belt (Thermohaline Circulation)

1. This deep current is generated primarily by *thermohaline circulation*: ∙Warm Gulf Stream water flows to the Norwegian Sea. ∙Freezing increases water salinity. ∙Cold, salty water is more dense, and sinks. ∙Warm Gulf Stream water moves in to take its place. ∙Warm water cools, sinks, and the cycle continues. ∙Cold water on the bottom flows south, past the equator, Antarctica. ∙Wind-driven upwelling brings cold water to the surface. ∙A "conveyor belt" is generated, encircling the globe. 2. The conveyor belt is *slow *(a few cm/sec). A drop of water staying in the belt would take about 1000 years to complete the circuit. 3. *Ocean warming due to anthropogenic climate change is causing the conveyor belt to slow down even more.* 4. Possible effects of this change are uncertain O_o

*Gastropoda/The Gastropods* (Mollusca, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. This group includes all free-living *snails and slugs*, which may be marine, freshwater or terrestrial. 2. Gastropods are characterized by: ∙High degree of cephalization ∙Well-developed sense organs ∙Single shell, often spiral or conical ∙Embryo undergoes *torsion*: -Caudal end twists around cranially -End result: anus is directly above the head; they poop on top of their head (Still believe in Intelligent Design?) -Some derived gastropods have undergone *detorsion*. 3. Brilliantly colorful *nudibranches* and *opisthobranchs* are quite poisonous.

*Bivalvia/The Bivalves* (Mollusca, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

1. This groups includes all hinge-shelled mollusks (clams, mussels, scallops, oysters). ∙There are both marine and freshwater species. ∙*Paired, hinged shells* entirely enclose the body. ∙A large *gill* is used for both respiration and feeding. ∙All are *suspension filter-feeders.* 2. *Unlike brachiopods, in bivalves the two shells are on the lateral surfaces of the animal, not dorsal and ventral.*

*Chondrichthyes/The Cartilaginous Fishes* (Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. This taxon includes *sharks, sawfishes, skates, and rays.* 2. Cartilaginous fishes: ∙Are all *carnivorous/predatory* ∙Have *placoid scales* derived from dermis ∙These scales also form the *replaceable teeth*. ∙Have a keen sense of smell ∙Sense vibrations with a lateral line system 2. A 380-million-year-old fossil shark, Gogoselachus lynbeazleyae, found in Western Australia has bone cell remnants in its cartilaginous skeleton. 3. This suggests that *the cartilaginous skeleton represents a derived condition, with bone secondarily lost*. 4. A few shark species are *obligate ram ventilators*: They must force water across the gills for oxygen, and so must swim constantly. ∙Family Lamnidae (e.g., Great White, Mako) ∙Whale Shark 5. Different types of egg laying animals: ∙*Skates* are *oviparous*. ∙*Sawfish* are *ovoviparous*. ∙*Rays* are *viviparous*. ∙*Sharks* may be *any of the above*, depending on species.

Coelomate Ecdysozoans

1. Three phyla of Ecdysozoans are: ∙Coelomate ∙Equipped with paired walking appendages on each segment 2. These are: ∙*Onychophora* (velvet worms) ∙*Tardigrada* (water bears) ∙*Arthropoda* (the joint-legged animals)

Muscle Tissue (Vertebrate Characteristics)

1. Together with the nervous system, *muscle tissue* facilitates movement. 2. Vertebrates have three types of muscle tissue, each specialized for different functions: ∙*Skeletal* striated muscle (voluntary control) ∙*Cardiac* striated muscle (involuntary control) ∙*Smooth* muscle (involuntary control) ∙*Tendons* attach skeletal muscle to bone ∙*Ligaments* attach bone to bone

Rocks and Soil (Abiotic Factors and Organic Evolution)

1. Topography creates habitat 2. The pH and mineral content of rock affect flora composition and diversity. 3. Composition of aquatic soil substrate affects water quality (dissolved minerals, pH). 4. Soil deposits can be ∙*Eluvium*- soil/sediments derived in situ by *weathering and/or gravity* (adjective = eluvial) ∙*Alluvium*- soil/sediments deposited by *running water *(adjective = alluvial)

*Trichinella* (Parasitic Nematodes, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

1. Trichinella spiralis causes trichinosis/trichinellosis. 2. It is transmitted via ingestion of undercooked meat infected with larval cysts.

Biochemical Cycles

1. Trophic interactions result in a cycling of energy and nutrients through the biosphere in systems we call *biogeochemical cycles.* 2. A generalized cycle can be superimposed on Biogeochemical Cycles for many different nutrients: ∙The Water Cycle ∙The Carbon Cycle ∙The Nitrogen Cycle ∙The Phosphorus Cycle ...and any other element. 3. *Our everyday activities have profound effects on these cycles.*

*Turtles and Tortoises* (Anapsids, Amniota, Reptiliomorpha, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1. Turtle and tortoise characteriistics: ∙Ectothermic poikilotherms ∙Three-chambered heart ∙Scaly, keratinous skin ∙Absence of teeth ∙Sharp cutting edges on *maxilla* and *mandible* ∙External bony shell consisting of: -Dorsal *carapace* -Ventral *plastron* -Shell is an integral part of the skeleton. 2. Turtles may be marine, fresh water, or terrestrial. 3. Tortoises are entirely terrestrial.

We Need Ecological Understanding

1. Understanding how ecosystems work helps us develop effective public policy to manage environmental support systems: ∙Watersheds ∙Agricultural lands ∙Wetlands ∙Forests ∙Urban and suburban areas 2. Ecology helps us solve or prevent anthropogenic environmental problems. It is unwise to take this knowledge for granted.

Disease Control (Biomedical)

1. Understanding the ecology of disease vectors allows more accurate, less toxic control. 2. Aedes aegypti (Yellow Fever Mosquito): ∙Prefers human host ∙Effective vector of Zika, Dengue fever, chikungunya, and other disease agents ∙Tropical, subtropical, temperate regions 3. Aedes albopictus (Asian Tiger Mosquito): ∙Feeds on mammals and birds as well as humans ∙Less likely to spread Zika, Dengue fever, chikungunya, etc. ∙Tropical, subtropical, temperate regions ∙More cold tolerant than A. aegypti 4. *Climate change may allow these species to spread farther north, carrying diseases with them.* 5. It's easier to attack an enemy that you know is coming.

Four Properties of Air Generate Air Currents

1. Unequal solar warming generates *atmospheric convection currents*. 2. Four (three??) properties of air influence the generation of these currents: ∙*Density* -Warm air expands, and is less dense than cool air -Warm air rises; cool air descends ∙*Water Vapor Saturation Point*: -As air temperature increases, it's capacity to hold water vapor increases. -When it reaches saturation point, water condenses and falls. -Cool air has a lower saturation point. -When warm wet air cools, you get precipitation. ∙*Latent heat release*: -Liquid water --> water vapor requires high energy input. -Water vapor --> liquid water releases the stored energy as heat. -At saturation point, air is warmed by this conversion.

Uniform Distribution

1. Uniform dispersion is a relatively uncommon pattern. It can result from negative intraspecific interactions such as ∙Territoriality ∙*Allelopathy*-exuding chemical to prevent adjascent growth

Epithelia (Vertebrate Characteristics)

1. Vertebrate internal and external surfaces are lined with well developed epithelia: 2. The external *integument* (skin) functions in: ∙*Protection* -First line of defense against pathogens and other foreign bodies. -Two layers: *epidermis* over *dermis* ∙*Thermoregulation* - Evaporative cooling and dermal blood supply are regulated by skin ∙*Vitamin D production* - Vitamin D precursor (7-dehydrocholesterol) is converted to Vitamin D upon exposure to UV light ∙*Absorption and secretion* - Skin absorbs and secretes water and water-soluble molecules. ∙*Respiration* - The skin is a vital respiratory organ in amphibians and some other vertebrates.

Food Webs

1.. Energy transfer in real ecosystems is almost never a simple chain. 2. Most organisms feed on (or are eaten by) more than one other type of organism. 3. The multiple, interweaving food chains create a complex *food web*. 4. Food Webs drive the flow of *energy* and *nutrients* through ecosystems.

*Actinopterygii/The Ray-finned (Bony) Fishes* (Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

1.. Ray-finned fish exhibit a vast array of form and natural history. At 24,000 species, they are the most diverse vertebrates. ∙Skeleton composed primarily of bone ∙Fin rays are composed of cartilage or bone ∙*Dermal scales* protrude through epidermis and shed easily. ∙Skin copiously supplied with *mucous glands* -*Mucous* is an adjective -*Mucus* is a noun ∙Fins are either: -Medial and unpaired -Lateral and paired ∙Toothy, terminal (i.e., at the end of the body) mouth ∙Gill arches covered by a bony operculum ∙*Swim bladder* (derived from gut) provides buoyancy. ∙*Two-chambered heart*

Life Tables

A *life table* is a representation of a population's age-specific survival, based on the survivorship of a given *cohort*.

Hydrostatic skeleton

A fluid skeleton in many soft-bodied invertebrates, including annelids, that allows an organism to change shape but not volume.

Evolutionary Adaptation

A genetic change affecting the physiology, biochemistry, or morphology of a species in response to natural selection. It *occurs over generations*, and does not occur in an individual.

*Amphibia* (Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

Amphibians are characterized by: ∙Being *ectothermal poikilotherms* ∙Scaleless, moist skin that is: -Respiratory in function -Equipped with poison glands ∙*Three-chambered heart* ∙Large mouth with very small teeth ∙Being insectivorous/carnivorous ∙Primitively *oviparous*, but may be *ovoviparous* or *viviparous* ∙*Aquatic larvae* (with *gills* and *lateral line system*)

Hadley Cells

At *30°N and 30°S*: ∙Hadley Cells form between the equator and 30° (N and S).cool air falls back to earth. ∙Falling air undergoes adiabatic heating. ∙By the time it reaches earth's surface, it is hot and dry. ∙Most of the world's deserts are located at 30°N and 30°S ∙The region where the two Hadley Cells meet is known as the *intertropical convergence zone (ITCZ).*

Pentaradial symmetry

Circular body plan that can be divided into 5 equal parts (echinoderms)

Carrion

Dead animal flesh

*Heart Worm* (Parasitic Nematodes, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

Dirofilaria immitis, the canine heartworm can be life-threatening.

Commensalism (+ , 0)

In a commensal relationship: ∙Species A benefits from the presence of Species B. ∙Species B is neither positively nor negatively affected by the presence Species A.

Filter feeding

In an aquatic animal, a method of feeding in which the animal traps organic material that is floating in the surrounding water

When an earthworm contracts the circular muscles of a particular segment, that segment should become?

Longer and thinner

Vertebrate Diveristy/Clades (Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

Major taxonomic groups of extant vertebrates: ∙*Agnathans* - jawless fishes ∙*Chondrichthyes* - cartilaginous fishes ∙*Actinopterygii* - ray-finned (bony) fishes ∙*Lobe-finned fishes* - coelacanths and lungfishes ∙*Amphibia* - salamanders, frogs, caecilians ∙*Mammalia* - mammals ∙*Testudines* - turtles ∙*Lepidosauria* - tuataras, lizards, snakes ∙*Archosauria* - crocodilians and birds

*Monotremata* (Mammalia, Synapsida, Amniota, Reptiliomorpha, Tetrapoda, Sarcopterygii, Gnathostomata, Vertebrata, Craniata, Chordata, Deuterostomia, Bilateria, Eumetazoa)

Monotreme mammals: ∙Are the only living mammals that lay eggs ∙Eggs are yolky, essentially reptilian in structure and development ∙Cone photoreceptors have oil droplets, as in reptiles/birds. ∙Oil droplets have been lost in all other mammals. ∙Y chromosome is similar to X chromosome. ∙Have a cloaca like that of diapsids 2. The *echidna* and the *platypus* are the only extant monotremes.

Permafrost

Permafrost is any ground that remains completely frozen—32°F (0°C) or colder—for at least two years straight. These permanently frozen grounds are most common in regions with high mountains and in Earth's higher latitudes—near the North and South Poles.

Symbiosis

Refers to populations of two different species engaging in interaction that affects each population both ecologically and evolutionarily.

When an earthworm contracts the longitudinal muscles of a particular segment, that segment should become?

Shorter and thicker

Population Age Structure

The age structure of a population can be illustrated with an *age structure pyramid*. The shape of the pyramid indicates whether population size is ∙*Stable* (highest frequency: reproductive adults) ∙*Increasing* (highest frequency: juveniles, young adults) ∙*Decreasing* (highest frequency: post-reproductive adults)

Logistic Growth Models: K and R selected species

The logistic growth model predicts population grow that both very high and very low population densities.

Deutrostome Phylogeny (Clades)

The major deuterostome clades are: 1. *Echinodermata* (The Spiny-skinned Animals) 2. *Hemichordata* (The Acorn Worms) 3.*Chordata* (The Chordates) ∙*Urochordata* (The Tunicates) ∙*Cephalochordata* (The Lancelets) ∙*Vertebrata* (The Vertebrates)

*Echinoderm Diversity/Clades* (Deuterostomia, Bilateria, Eumetazoa)

There are five extant clades within the Echinodermata. ∙*Crinoidea* - The Sea Lilies ∙*Asteroidea* - The Sea Stars ∙*Ophiuroidea* - The Brittle and Basket Stars ∙*Echinoidea* - The Sea Urchins and Sand Dollars ∙*Holothuroidea* - The Sea Cucumbers

Trilobites (all extinct) (Arthropoda, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

These iconic arthropods: ∙Were common in shallow waters of the Paleozoic oceans (250 mya) ∙Had a bilaterally symmetrical, metameric body ∙Had a chitinous exoskeleton ∙Exhibited early tagmosis of the head and thorax approaching a *cephalothorax* ∙Had paired, *undifferentiated appendages* on each segment

*Errantia* (Annelida, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

This group includes: ∙Mobile, marine polychaetes ∙Many predatory forms

*Sedentaria* (Annelida, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

This group includes: ∙Tube-dwelling, "sedentary" polychaetes ∙Earthworms and freshwater oligochaetes ∙Leeches

Controlled (non-regulated) variable

Variable is kept within a limited range by the organism's systems in the absence of sensors.

Sensed (regulated) variable

Variable kept within a limited range by physiological mechanisms responding to feedback from a sensor.

Workshop 1/Lecture 21

Workshop 1/Lecture 21

Workshop 2/Lecture 26

Workshop 2/Lecture 26

*Elephantiasis* (Parasitic Nematodes, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

Wuchereria bancrofti, Brugia malayi, and B. timorican cause lymphatic filariasis ("elephantiasis").

Temperate Rainforest

∙*Latitude*: ~ 40° - 60° north ∙*Climate*: cool and very wet ∙*Dominant vegetation*: Large coniferous trees; mosses, ferns, Acidity of organic matter deters decomposition, O horizon is thick, spongy, and very wet ∙*Biodiversity*: moderate/high ∙*Productivity*: moderate/high ∙*Keystone species*: Red-backed Vole; Spotted Owl ∙*Typical animals*: Black Bear, Grizzly Bear, Grey Wolf, Red Fox, Lynx, Wolverine, Moose, Elk, Spotted Owl, Trumpeter Swan, Bald Eagle, Golden Eagle, Tree squirrels, Many migratory birds, Aquatic turtles, Many amphibians, Many insects and arachnids

Taiga/Boreal Forest

∙*Latitude*: ~ 50° - 75° north and south ∙*Climate*: freezing winter (6-7 months); rainy, hot summer; brief autumn; brief, fertile spring with abundant flowering. ∙*Dominant vegetation*: coniferous trees -Conifers have a selective advantage over "broadleaf" (Anthophyte) plants here because they are not deciduous. -They can photosynthesize all year, even when days are very short. Anthophytes, being deciduous, cannot photosynthesize in autumn/winter. ∙*Biodiversity*: moderate ∙*Productivity*: moderate to high in growing season ∙*Keystone species*: conifers ∙*Typical animals*: Red Fox, Grey Wolf, Grizzly Bear, Black Bear, Lynx, Tiger (Siberia), Minks and other mustelids, Caribou, Moose, Deer (White-tailed; Elk), Tree squirrel species Eagles, Hawks, Falcons (raptors), Cottontails, Many migratory birds Turtles, Salamanders, frogs, Insects more diverse than in tundra

Tundra and Polar Ice

∙*Tundra latitude*: ~ 75° - 60° north (arctic) and south (antarctic) ∙*Polar Ice latitude*: ~ 60° - 90° north (arctic) and south (antarctic) Tundra: ∙*Climate*: cold, windy, arid; short growing season with abundant flowering forbs ∙*Dominant vegetation*: -Lichens, mosses, grasses, seasonal forbs -*Permafrost* is a thick layer of permanently frozen soil beneath an active layer of seasonally thawed topsoil. -It prevents penetration of deep roots, so limits the size of woody plants. ∙*Biodiversity*: moderate; higher than polar zones ∙*Productivity*: moderate in growing season ∙*Keystone species*: lichens, lemmings ∙*Typical animals*: Arctic Fox, Arctic Wolf, Grizzly Bear, Polar Bear, Ermine, Lemming, Caribou, Musk Ox, Snowshoe Hare, Arctic Ground Squirrel, Snowy Owl, Gyrfalcon, Ptarmigan, Harlequin Duck, Many migratory birds Bees, mosquitos and other flies (seasonal)

*Scaphopoda/The Tusk Shells* (Mollusca, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

∙All *marine* ∙All *benthic* ∙Tubular, tusk-shaped shell is open at both ends. ∙Adults live their lives buried in sediment, head down. ∙Tentacle-ringed head lacks sense organs except *statocysts* (gravity sensing organ).

Simple Metamorphosis (Arthropods)

∙Is also known as *ametabolous* or *gradual* metamorphosis ∙No free-living larval stage ∙Juveniles have the same form as the adult, but smaller. ∙Juvenile form is called a *nymph* Examples: silverfish, springtail, grasshopper, cockroach

Mixed Metamorphosis (Arthropods)

∙Is also known as *hemimetabolous* metamorphosis ∙Larval form (nymph) is different from adult form ∙*Larval form is reminiscent of adult form* ∙An aquatic nymph is called a *naiad* ∙Sequential metamorphic changes generate the fully adult form. Examples: dragonfly, damselfly, cicada

Complete Metamorphosis (Arthropods)

∙Is also known as *holometabolous* metamorphosis ∙Larval and adult morphologies are distinctly different. ∙Morphology changes in stages. ∙Typically, developmental stages are egg --> larva --> pupa --> adult Examples: butterflies, moths, flies, beetles

*Leeches* (Sedentaria, Annelida, Lophotrochozoa, Protostomia, Bilateria, Eumetazoa)

∙Leeches inject prey with saliva containing a powerful anticoagulant, *hirudin*. ∙This has long been used to treat patients who have suffered stroke, embolism, or other clotting disorder. ∙More recently, medicinal leeches have been applied to replanted limbs and other appendages. ∙As they feed on the area, the hirudin *dissolves clots and promotes circulation* by reducing swelling.

*Horseshoe Crabs* (Chelicerata, Arthropoda, Ecdysozoa, Protostomia, Bilateria, Eumetazoa)

∙Only four extant species ∙Most common is the Horseshoe Crab, found along our Florida coastlines. ∙Compound eyes are embedded in the flexible carapace. ∙Horseshoe crabs walk along the ocean bottom on their jointed legs. ∙They feed on worms and other small prey. ∙Their blood could save your life.