Biology 150 Learning Objectives for November 17-29

pelagic realm

-(pelagic zone) -all of the ocean's open water

biogeographical realms

-also called biogeographical regions -based on history -large spatial regions within which ecosystems share a broadly similar biological evolutionary history -8 terrestrial biogeographical realms are typically recognized, corresponding roughly to continents -represent large areas of the Earth's surface within which organisms have been evolving in relative isolation over long periods of time, separated from one another by geographic features such as oceans, deserts, mountains, that constitute barriers to migration -used to indicate general groupings of organisms based on their shared biogeography -patterns of distribution of living things in the realms were shaped by the process of plate tectonics, which has redistributed the world's land masses over geological history -terrestrial realms reflect freshwater biodiversity patterns well, but marine realm are poorly known and largely undefined -characterized by the evolutionary history of the organisms they contain -each realm may include many different biomes -a tropical moist broadleaf forest in central america, for example, may be similar to one in new guinea in its vegetation type and structure, climate, soils, etc. but these forests are inhabited by animals, fungi, micro-organisms and plants with very different evolutionary histories -species composition varies markedly depending on the biogeographic realm in which they are found.

describe chaparral biomes

-also called the scrub forest -found in california, along the mediterranean sea, and along southern coast of australia -annual rain ranges from 65-75 cm and majority of rain falls in the winter -summers are very dry and many chaparral plants are dormant during the summertime -vegetation: dominated by shrubs and is adapted to periodic fires, with some plants producing seeds that only germinate after a hot fire -the ashes left behind after a fire are rich in nutrients like nitrogen that fertilize the soil and promote plant regrowth

boreal forests biome

-also known as taiga and coniferous forest -found south of the arctic circle and across most of canada, alaska, russia, and northern europe -cold, dry winters, and short, cool, wet summers -annual precipitation: 40-100 cm and usually takes the form as snow -little evaporation occurs because of cold temps -long and cold winters led to the predominance of cold-tolerant cone-bearing plants: coniferous evergreen trees like pine, spruce and fir which retain their needle-shaped leaves all year -evergreen trees can photosynthesize earlier in spring than deciduous trees because less energy from the sun is required to warm a needle-like leaf than a broad leaf, which benefits evergreen trees so they grow faster than deciduous trees in the boreal forest -soils tend to be acidic with little available nitrogen -leaves are a nitrogen-rich structure and deciduous trees produce a new set of these nitrogen-rich structures each year, therefore, coniferous trees that retain nitrogen-rich needles may have a competitive advantage over the broad-leafed deciduous trees -net primary productivity is lower than temperate forests and tropical wet forests -aboveground biomass is high because slow-growing tree species are long lived and accumulate standing biomass over time -plant species diversity is less than that seen in temperate and tropical wet forests -lack the pronounced elements of the layered forest structure seen in tropical wet forests -structure: a tree layer and then a ground layer -when conifer needles are dropped, they decompose more slowly than broad leaves, therefore, fewer nutrients are returned to the soil to fuel plant growth

describe tropical rain forests biome

-also known as tropical wet forests -found in equatorial regions -vegetation: plants with broad leaves that fall off throughout the year -trees do not have a seasonal loss of leaves; forests are "evergreen" year-round -temperature and sunlight are very stable (20-34 degrees C) -lack seasonal temperature variation in comparison to other biomes -lack of seasonality leads to year-round plant growth, rather than seasons -do not have long and short days during yearly cycle, instead they have a constant daily amount of sunlight (11-12 hrs per day), provides more solar radiation and therefore longer period of time for plant growth -annual rainfall: 125-660 cm with some monthly variation; very variable unlike sunlight and temperature -have wet months that could have more than 30 cm of precipitation, as well as dry months with fewer than 10 cm, but the driest month still exceeds the annual rainfall of some other biomes, such as deserts -high net primarily productivity due to the annual temperatures and precipitation values being ideal for plant growth -extensive biomass present=highly diverse species of plant communities -more species of trees than any other biome -horizontal layers of the biome: 1. forest floor: has a sparse layer of plants and decaying plant matter 2. understory: above floor, consists of short shrubbery foliage 3. layer of trees rise above this understory and is topped by a closed upper canopy (the uppermost overhead layer of branches and leaves) 4. some additional trees emerge through this canopy. -these layers provide diverse and complex habitats for the variety of organisms

net primary productivity

-an estimation of all of the organic matter available as food -estimated by measured the aboveground biomass per unit area, excluding roots -important when considering differences in biomes -very productive biomes have high level of above ground biomass -energy that remains in primary producers after accounting for respiration and heat loss, and which is then available to primary consumers at the next trophic level

hydrosphere

-area of the earth where water movement and storage occurs: as liquid water on surface and beneath surface or frozen, and as water vapor in the atmosphere

assimilation

-biomass of the present trophic level after accounting for the energy lost due to incomplete ingestion of food, energy used for respiration, and energy lost as waste

what are species distribution patterns based on

-biotic and abiotic factors and their influences during the very long periods of time required for species evolution (history)

how do the biota of biomes reflect adaptations to similar climate patterns?

-by distantly related lineages

ecosystems

-community of living organisms and their interactions with their abiotic environment -can be small (ex: tide pools found near rocky shores of many oceans) or large (amazon rain forest)

emergent vegetation

-consists of wetland plants that are rooted in the soil but have portions of leaves, stems, and flowers extending above the water's surface

abyssal zone

-deepest part of ocean -very cold, high pressure, oxygen content, and low nutrient content -no plants

Why are mathematical models created? 12/1

-design nuclear weapons -model climate

three major processes that generate biogeographical patterns

-dispersal -vicariance -extinction

net consumer productivity

-energy content available to the organisms of the next trophic level

biotic homogenization

-everywhere is becoming more or less the same- organisms that can thrive in human dominated landscapes, at the expense of narrow endemics and those species that do not adapt

describe subtropical deserts biome

-exist between 15 and 30 degrees north and south latitude; centered on the Tropics of Cancer and Capricorn -very dry; evaporation exceeds precipitation in some years -hot deserts can have daytime soil surface temps above 60 degrees C and nighttime temps approaching 0 degrees C -cold deserts temps can be as high as 25 deg. C and can drop below -30 deg. C -low annual precipitation fewer than 30 cm with little monthly variation and lack of predictability in rainfall -annual rain can be as low as 2 cm in ones located in central australia and northern africa -vegetation and low animal diversity is closely related to this low/unpredicatable precipitation -lack perennial vegetation that lives from one year to the next -many plants are annuals that grow quickly and reproduce when rain occurs, and then die -many have adaptations that conserve water such as deep roots, reduced foliage, and water-storing stems -seed plants here produce seeds than can be in dormancy for extended periods between rains -animal adaptations: nocturnal behavior and burrowing

benthic realm

-extends along the ocean bottom from the shoreline to the deepest parts of the ocean floor-consists of photic and aphotic zone

neritic zone

-extends from the intertidal zone to depths of about 200 m at the edge of the continental shelf -water contains silt and is well oxygenated, low in pressure, and stable in temp -sargassum provide a habitat for some sea life found here -zooplankton, protists, small fishes, and shrimp are found here and are the base of the food chain for most of the world's fisheries

describe temperate grasslands biome

-found in central north america, known as prairies -found in eurasia, known as steppes -annual fluctuations in temperature with hot summers and cold winters -annual temp variation produces specific growing seasons for plants -plant growth is possible with warm temps to sustain growth and when ample water is available, which occurs in the spring summer and fall -temps and water (stored as ice during the time) are low in winter, so not available for plant growth -annual rain: 25-75 cm -few trees due to low rainfall, except for the ones growing along rivers and streams -dominant vegetation: grasses and some prairies sustain populations of grazing animals -vegetation is very dense and soil is fertile because the subsurface of the soil is packed with roots and rhizomes (underground stems) of these grasses. The roots and rhizomes act to anchor plants into the ground and replenish organic material (humus) in the soil when they die and decay -fires, mainly caused by lightening, are a natural disturbance in these biomes; when fire is suppressed, the vegetation eventually converts to scrub and dense forests. -Often, the restoration or management of these environments requires the use of controlled burns to suppress the growth of trees and maintain the grasses

three broad categories of ecosystems based on their general environment

-freshwater -ocean water -terrestrial

wetlands

-freshwater biome -soil is either permanently or periodically saturated with water -different from lakes because wetlands are shallow bodies of water whereas lakes vary in depth -emergent vegetation consists of wetland plants that are rooted in the soil but have portions of leaves, stems, and flowers extending above the water's surface -ex: marshes, swamps, bogs, mudflats, salt marshes -shared characteristics: hydrology, hydrophytic vegetation, and hydric soils -marshes and swamps: slow and steady water flow -bogs: develop in depressions where water flow is low or nonexistent; usually occur where there is a clay bottom with poor percolation; water is stagnant and oxygen depleted; low net primary productivity because of low nitrogen and oxygen

percent of earth each ecosystem occupies

-freshwater: 1.8% -ocean: 75% -terrestrial: the rest

biotic relaxation (extinction debt)

-good news: we can clear a lot of tropical forests and 95% of species are still there -bad news: there is a drop off a few years later, because it could be a single organism of the species so it could maybe not find a mate or have trouble surviving and carrying on another lineage

describe savannas biome

-grasslands with scattered trees -located in africa, south america, northern australia -hot, tropical -temperatures from 24-29 degrees celsius -annual rainfall of 10-40 cm -extensive dry season, so the forest trees do not grow as well as they do in tropical wet forests or other forest biomes -within the biome, the grasses and forbs (herbaceous flowering plants) dominate, there are few trees -fire is important source of disturbance in the biome, so plants have well-developed root systems that allow them to quickly re-sprout after a fire

the number of species on earth has _____ over time

-increased

what has lineage diversification included

-increases in the number of species -variety of morphologies -diversity of niches

biomagnification

-increasing concentration of persistent, toxic substances in organisms at each trophic level, from the primary producers to the apex consumers -many substances shown to bioaccumulate (ex: pesticide DDT) -some aquatic ecosystems: organisms from each level consumed many from the lower level, which caused DDT to increase in birds (apex consumers) that ate fish; thus, birds accumulated sufficient amounts of DDT to cause fragility in eggshells, increasing breakage during nesting and was shown to have adverse affects on these bird populations.

describe freshwater biomes

-lakes and ponds (standing water) as well as rivers and streams (flowing water) -also include wetlands -humans rely on these to provide drinking water, crop irrigation, sanitation, and industry (ecosystem services)

biomes

-large areas of land with similar climate, flora, and fauna -abiotic factors influence the distribution of biomes -"major habitat types" -divisons of the earth's surface based on life form, or the adaptation of animals, fungi, micro-organisms and plants to climatic, soil , and other conditions -characterized by similar climax vegetation -formation of plants and animals that have common characteristics due to similar climates and can be found over a range of continents. -distinct biological communities that have formed in response to a shared physical climate. -distinct from habitats, because any biome can comprise a variety of habitats -adaptions to regional climates -net primary productive is important when considering differences in biomes

describe the ocean biome

-largest marine biome -continuous body of salt water that is relatively uniform in chemical composition -weak solution of mineral salts and decayed biological matter -physical diversity is a significant influence on all organisms -categorized into different zones based on how far light reaches into the water, each has a distinct group of species adapted to the biotic and abiotic factors to that zone -zones: intertidal, neurotic, oceanic, and abyssal

arctic tundra biome

-lies north of the subarctic boreal forest and is located throughout the Arctic regions of the northern hemisphere -average winter temp: -34 degrees C -average summer temp: 3-12 degrees C -plants have very short growing season approx. 10-12 weeks long, but during this time, there are almost 24 hours of daylight and plant growth is rapid -very low annual precipitation and little annual variation -little evaporation due to cold temps. -plants are generally low to ground -little species diversity -low net primary productivity -low aboveground biomass -soils remain in a perennially frozen state referred to as permafrost: makes it impossible for roots to penetrate deep into the soil and slows the decay of organic matter, inhibiting the release of nutrients from organic matter -during growing season, the ground can be completely covered with plants or lichens

food chain

-linear sequence of organisms through which nutrients and energy is passed -primary producers, primary consumers, secondary consumers, tertiary consumers (apex: at the top of chain) -energy limits the length of food chains -this linear model is not accurate to describe most ecosystems because some organisms feed on other levels/multiple levels -good because it is more flexible for analytics modeling, easier to follow, and to experiment with

How does energy limit the length of food chains?

-lost as heat between each trophic level due to the 2nd law of thermodynamics -after a limited # of trophic energy transfers, the amount of energy remaining in the food chain may not be great enough to support viable populations at yet a higher trophic level

temperate forests biome

-most common biome in eastern north america, western europe, eastern asia, chile, and new zealand -found throughout mid-latitude regions -temps range between -30 and 30 degrees C, and drop to below freezing on an annual basis, which means that this biome has defined growing seasons during the spring, summer, and early fall -annual rainfall relatively constant: 75-150 cm -moderate rainfall and temps=deciduous trees as dominant plant because they lose their leaves each fall and remain leafless in winter, thus, no photosynthesis occurs during the dormant winter period. Each spring, new leaves appear as temp increases -Due to the dormant period, net primary productivity is less than of tropical wet forests and show less diversity of tree species -trees lead out and shade much of the ground, but this biome is more open than rain forests because trees in this biome do not grow as tall as the trees in the tropical wet forests -soils are rich in inorganic and organic nutrients due to the thick layer of leaf litter on forest floors. As lead litter decays, nutrients are returned to the soil. The litter also protects soil from erosion, insulates the ground, and provides habitats for invertebrates and their predators

competitive release

-non-native species can become invasive because they are not coevolved with other species in the community- -check powerpoint 12/1

describe coral reef biome

-ocean ridges formed by the marine invertebrates living in warm shallow waters within the photic zone of the ocean -found within 30 degrees north and south of equation -great barrier reef is a well known system located off northeastern coast of Australia -other systems: fringing islands, which are directly adjacent to land, or atolls, which are circular reef systems surrounding a former landmass that is now underwater -coral organisms (cnidaria phylum) are colonies of saltwater polyps that secrete calcium carbonate skeleton, that slowly accumulate, forming underwater reef -corals found in shallower waters (60 m-200 ft) have a mutualistic relationship with photosynthetic unicellular algae; this provides corals with majority of nutrition and energy they need -the waters in which these orals live are nutritionally poor and without this mutualism, it would not be possible for large corals to grow -some corals living in deeper and colder water do not have a mutualistic relationship with algae; these corals attain energy and nutrients using stinging cells on their tentacles to capture prey -more than 4000 fish inhabit coral reefs that can feed on coral, the cryptofauna, or the seaweed and algae that are associated with the coral -some fish species inhabit the boundaries of a coral reef; these include predators, herbivores, or planktivores

oceanic zone

-open ocean area beyond neritic zone -thermal stratification within this zone, where warm and cold waters mix because of ocean currents

rivers and streams

-part of freshwater biome -continuously moving bodies of water that carry large amounts of water from the source (headwater) to a lake or ocean -larges rivers: nile river in africa, amazon river in south america, and mississippi river in north america -abiotic features vary along the length of the river or stream -streams begin at the point of origin (source water) which is usually cold, low in nutrients and clear -the channel (width) is narrower than at any other place along the length of the river or stream, so the current is often faster here than at any other point -fast-moving water= minimal silt accumulation at bottom, so water is clear -photosynthesis here is mostly attributed to algae growing on rocks -swift current inhibits the growth of phytoplankton -additional input of energy can come from leaves or other organic material that falls into the river or stream from trees and other plants that border the water -when leaves decompose, the organic material and nutrients in the leaves are returned to the water -plants and animals have adapted to this fast-moving water -width gradually widens and current slows as water moves away from source -slow-moving water caused by gradient decrease and volume increase as tributaries unite, has more sedimentation -phytoplankton can be suspended in slow moving water, so water will not be as clear as it is near the source -water is also warmer -worms and insects found burrowing in mud -higher order predator vertebrates include waterfowl, frogs, and fishes -these must find food in slow moving, sometimes murky, waters and unlike the trout at the source, they may not be able to use vision as their primary sense to find food, instead, use taste or chemical cues to find prey

describe lakes and ponds

-part of freshwater biome -lakes and ponds are found in terrestrial landscapes and therefore are connected with abiotic and biotic factors influencing these terrestrial biomes -can range in area from a few square meters to thousands of square km -temperature is important abiotic factor affecting living things -in the summer, thermal stratification occurs -phytoplankton found in photic zone and carry out photosynthesis -zooplankton consume phytoplankton -at bottom, bacteria in aphotic zone break down dead organisms that sink to bottom -nitrogen and phosphorous are important limiting nutrients; determining factors of phytoplankton growth -algal bloom result from large nitrogen and phosphorous input and can become so extensive that they reduce light penetration in water, resulting in water becoming aphasic and photosynthetic plants cannot survive -when algae die and decompose, severe oxygen depletion of the water occurs -fishes and other organisms that require oxygen are more likely to die= dead zones are found across the globe

rates of speciation and extinction _____ _____ over time

-rates have varied over time

food web

-representation of a holistic, non-linear web of primary producers, consumers, etc. used to describe ecosystem structure and dynamics -more accurate rep for ecosystems structure and dynamics than food chain because it accounts for all of the interactions between different species and their complex interconnected relationships with each other and the environment -data can be used as input for simulation modeling

ocean upwelling

-rising of deep ocean waters that occurs when prevailing winds blow along surface waters near a coastline -wind pushes ocean waters offshore, water form both of ocean moves u to replace this water -as a result, nutrients once contained in dead organisms become available for reuse by other living organisms

spring and fall turnover

-seasonal process that recycles nutrients and oxygen from the bottom of a freshwater ecosystem to the top of a body of water -caused by a thermocline -water has a max density go 4 degrees C. surface water temp changes as the seasons progress, and denser water sinks

footprint in east africa found in volcanic ash? (powerpoint from 12/1)

-sexual dimorphism?

permafrost

-soil in a perennially frozen state -makes it impossible for roots to penetrate deep into soil and slows decay of organic matter, which inhibits the release of nutrients from organic matter

endemic species

-species naturally found only in a specific geographic area that is usually restricted in size -ex: venus flytrap- endemic to small area in north and south carolina

generalists

-species which live in a wide variety of geographic areas -ex: raccoon-native to most of north and central america

biogeography

-study of the geographic distribution of living things and the abiotic factors that affect their distribution

geographical distributions of _____ have changed over time

-taxa

Abiotic factors and how they affect the distribution of organisms

-temperature and rainfall -as these change, the composition of plant and animal communities change

primary factors that limit the distribution and abundance of species

-temperature: effects metabolism -energy sources -water: critical for cellular processes -inorganic nutrients and soil (nitrogen and phosphorous) -other aquatic factors such as oxygen -other terrestrial factors such as wind and fire, because wind influences rate of evaporation and transpiration and can move soil, water, or other abiotic factors, as well as organisms, and fire can be an important agent of disturbance in terrestrial ecosystems, some being adapted to fire and thus require the high heat of it to complete a part of their life cycle

productivity within an ecosystem and most important organisms of this role

-the percentage of energy entering the ecosystem incorporated into the biomass in a particular trophic level -primary producers especially important in this part because they bring energy to other living organisms

what has changed about land and oceans over time? what is another thing that has changed over time (intrinsic and extrinsic)?

-the positions of them -climate has also changed (intrinsic and extrinsic)

How can bipedalism be identified?

-through fossil fragments of the shoulder, hip, or foot

biomass

-total mass in a unit area at the time of measurement of living or previously living organisms within a tropic level

aboveground biomass

-total mass of living plants -very productive biomes have high level of above ground biomass

canopy

-uppermost layer of branches and leaves

second law of thermodynamics

-whenever energy is converted from one form to another, there is a tendency toward disorder (entropy) in the system -basically saying that a great deal of energy is lost as metabolic heat when the organisms from one trophic level consume the next level

estuaries biome

-where the ocean meets fresh water -example: where river meets the ocean -both fresh and salt water are found in the same vicinity, mixing results in a disputed brackish saltwater -form protected areas where many of the young offspring of crustaceans, mollusks, and fish begin their lives -salinity is a very important factor that influences the organisms and adaptions of them found in estuaries -salinity varies and is based on rate of flow of its freshwater sources -once or twice a day, high tides bring salt water in -low tides occurring at the same frequency reverse the current of salt water -short-term and rapid variation in salinity due to the mixing of fresh and salt water is a difficult physiological challenge for organisms -many estuarine plants are halophytes (can tolerate salty conditions); adapted to deal with the salinity resulting from saltwater on their roots or from sea spray; in some, filters in the roots remove the salt from the water that the plant absorbs; other plants are able to pump oxygen into their roots. -animals such as mussels and clams, have developed behavioral adaptations that extend a lot of energy to function in this rapid changing environment -when these animals are exposed to low salinity, they stop feeding, close shells, and switch from aerobic (uses gills) to anaerobic respiration (does not require oxygen). -when high tide returns, salinity and oxygen content of water increases, and animals open their shells, begin feeding, and return to aerobic respiration

aphotic zone

-within benthic realm -depths greater than 200 m in which light cannot penetrate -majority of the ocean -lacks sufficient light for photosynthesis

photic zone

-within the benthic realm -portion of ocean that light can penetrate -approx 200 m

intertidal zone

-zone between high and low tide -closest to land -extremely variable because of tides

two types of food webs

1. grazing food web: plants or other photosynthetic organisms at its base, followed by herbivores and then carnivores 2. detrital food web: base of organisms that feed on decaying organic matter, called decomposers or detritivores (usually bacteria or fungi that recycle)

What are the three main aquatic biomes?

1. ocean 2. coral reefs 3. estuaries

what are the two parameters used to measure changes in ecosystems and what do they mean?

1. resistance: ability of an ecosystem to remain at equilibrium in spite of disturbances 2. resilience: speed at which an ecosystem recovers equilibrium after being disturbed *important when considering human impact*

What are the 8 major terrestrial biomes?

1. tropical wet forest (tropical rain forest) 2. savannas 3. subtropical deserts 4. chaparral (scrub forest) 5. temperate grasslands 6. temperate forests 7. boreal forests (coniferous forest) 8. arctic tundra

current patterns are a function of both ____ and _____ ______

a function of both biogeography (history) and the adaptations to regional climates (biomes)

thermocline

a layer of water with a temperature that is significantly different from that of the surrounding layers

communities

all living things within specific habitats

one biggest problem

global climate change

gross primary productivity

rate at which photosynthetic primary producers incorporate energy from the sun

equilibrium

steady state of ecosystem where all organisms are in balance with their environment and with each other

biogeochemical cycle

the recycling of inorganic mater between living organisms and their environment