bio 121 exam 2

pests evolve resistance to pesticides

Chemical pesticides tend to become less effective over time as pests evolve resistance to them. Most pests occur in huge numbers, so it is likely that a few have genes that detoxify or metabolize a given pesticide Individuals that can metabolize and detoxify a pesticide survive and pass these genes to their offspring. As the population of pests with those genes increases, fewer pests are affected by the pesticide Pesticides lose effectiveness as pests evolve resistance "Pesticide treadmill" Chemists increase the toxicity of pesticides to compete with resistant pests Over 586 species are resistant to 330 insecticides Hundreds of weeds and plant diseases have evolved resistance to herbicides and pesticides Many species have evolved resistance to multiple chemicals Green peach aphid, Colorado potato beetle, diamondback moth Individuals with the gene will survive and reproduce at greater rates, creating a new generation with a much higher rate of carrying the gene. Eventually the pesticide becomes ineffective and must be replaced by a new one. This is called the "pesticide treadmill pests attack crop; pesticide is applied; most pests are killed a few with innate resistance survive; survivors breed and produce a pesticide resistant pop; pesticide applied again; pesticide has little effect now more toxic pesticides are developed

recombinant dna

Combined DNA segments from multiple organisms

communities may undergo shifts

Communities do not pass through the stages of succession evenly; ecological conditions may promote or inhibit progression. At times, communities may undergo a regime shift, meaning that the entire character of the community changes from the disturbance. Occurs from climate change, loss of a keystone species, or introduction of an invasive species. In some cases, human disturbance is causing novel communities, which are mixtures of species that have not previously occurred on the Earth.

diversity and community stability

Communities with higher diversity are More productive; they produce more biomass (the total mass of all organisms) More stable in their productivity Better able to withstand and recover from environmental stresses More resistant to invasive species

permanent modicifcation or destruction

Community never returns to its original state

conservation

Conserving species often requires resolving conflicts between habitat needs of endangered species and human demands Most Americans support protecting endangered species Opponents feel that the ESA values endangered organisms more than the livelihood of people Protection will restrict land use and cost jobs Landowners conceal the presence of endangered species on their land.... "Shoot, shovel, and shut up" But the ESA has stopped few development projects Landowners are allowed to take actions that harm species if they improve habitat for the species in other places

boreal forest (taiga)

Cool and dry climate Long, cold winters Short, cool summers Nutrient-poor, acidic soil Dominated by a few evergreen tree species Moose, wolves, bears, lynx, migratory birds Boreal forests, also called taiga, are also cold, but receive more precipitation than tundras. They are dominated by few species of evergreen trees. Soils are acidic and nutrient-poor. norway

traditional agriculture

Cultivating, harvesting, and distributing crops performed by human and animal muscle power, hand tools, and simple machines Plant polycultures - mixtures of different crops in small plots of land many human cultures shifted from hunter-gatherers to permanent settlements with farming. In traditional agriculture, the work of cultivating, harvesting, and distributing crops was performed by human and animal muscle power. Most farmers planted polycultures, mixtures of different crops in small plots of land.

wildlife declines in african reserves

Tanzania and Kenya have some of the world's most famous parks and protected areas Biologists and park managers have censused wildlife in and around the parks and reserves Most animals are declining in number inside and outside the parks and reserves Both wet- and dry-season census data showed the same results Thomson's gazelles in Maasai Mara National Reserve Most abundant species Decreased by 59% inside reserve Decreased by 77% outside the reserve Researchers concluded that setting aside parks is not adequate to conserve wildlife and ecosystems Conservation success requires: Linking reserves with corridors of habitats that animals can use Working with local people living near protected areas Community-based conservation encourages people to be stewards Manage natural resources in the areas they live

biological community

an assemblage of populations of different species that live in the same area and interact with each other Interspecific interactions are interactions between different species Community interactions are classified by whether they help, harm, or have no effect on the survival and reproduction of species involved

herbivory

an interaction in which an herbivore eats parts of a plant or alga It has led to evolution of plant mechanical and chemical defenses and adaptations by herbivores animals feed on the tissues of plants. Insects are the most common type of herbivore. Plants have also evolved defenses, such as toxic chemicals, thorns, spines, or irritating hairs. Figure 54.6 A West Indies manatee (Trichechus manatus) in Florida. Herbivores feed on tissues of plants It may not kill the plant but affects its growth and reproduction Defenses against herbivory include Chemicals: toxic or distasteful Mechanical defenses: thorns, spines, tough coverings, or irritating hairs Herbivores may overcome these defenses

facilitation

an interaction in which one species has positive effects on another species without direct and intimate contact (not a symbiotic relationship)

mutualism

an interspecific interaction that benefits both species A mutualism can be... Obligate facultative is a relationship where two or more species benefit each other. Many mutualistic relationships occur between species as part of symbiosis - a close physical association between species. Other relationships, such as in pollination, only require free-living organisms to encounter each other once. Birds or insects transfer pollen from flower to flower, causing fertilization. Each provides a service the other needs (food, protection, housing, etc.) Microbes within digestive tracts Mycorrhizae: plant roots and fungi Coral and algae (zooxanthellae) Pollination Bees, bats, birds, and others transfer pollen from one flower to another, fertilizing its eggs

disturbance

any event that has rapid and drastic effects on the community and ecosystem Disturbances can be small and localized, such as a tree falling and creating a gap in the forest canopy. Disturbances can be large, like hurricanes. Disturbances may also recur regularly, such as prairie fires or insect outbreaks.

irrigation

artificially providing water beyond what is received by precipitation in order to support agriculture Unproductive regions become productive farmland 70% of fresh water is for irrigation Depletes aquifers and dries up rivers and lakes The artificial provision of water beyond what is received by precipitation is irrigation. Irrigation is necessary with water-intensive crops (like rice) and in areas with dry climates. Irrigation is the largest use of water by humans, making up 70% of all fresh water withdrawn.

Community

assemblage of different populations that live together in a defined area

succession aquatic

Aquatic systems can also undergo succession Ponds eventually fill in to become terrestrial systems

desertfication reduces productivity of arid lands

Arid and semi-arid environments that cover about 40% of Earth's land surface Prone to desertification Loss of more than 10% productivity due to erosion, soil compaction, deforestation, overgrazing, drought, salinization, water depletion, climate change Endangers the food supply of 1 billion people in over 100 countries Costing tens of billions of dollars each year Much of the world's population lives in drylands, arid and semi-arid environments that cover about 40% of the Earth's land surface. Drylands are prone to desertification, a land degradation where more than 10% of productivity is lost. Wind and water erosion are the biggest causes.

biomes and ecotone

biomes usually grade into each other, without sharp boundaries The area of intergradation, called an ecotone, may be wide or narrow

food

As many as 80,000 edible wild plant species could be utilized by humans plant breeders bred virus-resistant commercial rice by crossing it with a wild population

biodiversity loss involves pop declines

As populations shrink The species loses genetic diversity Its geographic range gets smaller

asian carp

Asian carp became invasive, outcompeting native fish for zooplankton and stirring up sediment as they consume native plants and mollusks. Eradication of an invasive species is extremely difficult, so managers aim to control populations. Since the 1990s, federal funding has been provided for control measures: Netting juvenile fish, contracting fishermen to catch adults, bubbling carbon dioxide into the water, and broadcasting noise into the water Control and eradication have been very expensive, so now attention is given to preventing future invasions.

innovative solutions in hawaii

At Hakalau Ranchland is being restored to forests Invasive plants are being removed and native ones planted Animals are being protected while new populations are being established Across Hawaii People are protecting land Restoring native habitats Protecting areas offshore

feedlot agriculture has benefits and costs

Benefits Allow greater economic efficiency Greater production of more affordable meat Reduce grazing impacts on the land Costs 45% of the world's grain is fed to livestock Which endangers food security for the world's poor Feedlots produce huge amounts of manure and urine Can pollute surface water and groundwater Feedlot waste is rich in nitrogen and phosphorous, so it contributes to eutrophication Feedlot waste contains bacterial and viral pathogens Hormones, antibiotics, and other drugs administered to animals may also be excreted Produces more greenhouse gases (CO2, methane, nitrous oxides) than automobile emissions

aquacultures benefits and disadvantages

Benefits Reduces pressure on plummeting populations of overharvested wild fish increases food supplies and protein sources, increasing overall food security Uses fewer fossil fuels, is safer, and produces more fish than commercial fishing Drawbacks Lots of waste produced Uses grain, which affects food supplies for people Fish meal is made from wild ocean fish Escaped fish introduce disease or outcompete wild fish Degradation of coastal ecosystems Due to plummeting wild fish populations and increasing demand for seafood, aquaculture, the cultivation of aquatic organisms in controlled environments, may be the answer. Aquaculture increases food supplies and protein sources, increasing overall food security. Also helps to reduce overfishing of wild fish and the unintended catch of other organisms called bycatch. Negative consequences include antibiotic overuse, degradation of coastal ecosystems, and spreading disease or invasive species into nearby ecosystems.

biophilia

Biodiversity's benefits go beyond economics Humans love nature and have an emotional bond with other living things Our affinity for parks and wildlife, our love for pets High value of real estate with views of natural lands Our interest in hiking, bird-watching, fishing, hunting, backpacking Nature deficit disorder" (Richard Louv, 2005 book) Alienation from biodiversity and nature damages childhood development May lie behind many emotional and psychological challenges young people in developed nations face today

biomass decreases at higher trophic levels

Biomass is the collective mass of living matter in a given place and time There are far fewer organisms and less biomass (mass of living matter) at the higher trophic levels At each trophic level, most of the energy input is either used for maintenance or lost as heat. A trophic level will only have about 10% of the energy content, organisms, and biomass compared to the level below it. Biomass is the collective mass of living matter in a given place and time. The pyramid pattern of energy and biomass illustrates why eating at lower trophic levels decreases your ecological footprint.

phylogenetic trees

Branching diagrams that depict hypotheses about evolutionary relationships among species, groups, genes, etc. Represent life's history

temperate deciduous forest

Deciduous trees lose their broad leaves each fall Winters are frozen Fairly stable year-round precipitation Mid-latitude forests in Europe, east China, eastern North America Fertile soils Forests: oak, beech, maple smoky mts

undernutrition pt 2

Deficiency of one or more essential nutrients Receiving fewer nutrients and calories than one's minimum dietary energy requirements insufficient carbohydrates, proteins, essential lipids, vitamins, and/or minerals Impairs growth, pregnancy, lactation, physical work, cognitive function and disease resistance and recovery Poverty, politics, conflict, and inefficiencies in distribution contribute to hunger

food webs show feeding relationships and energy flow

food chain - A series of feeding relationships food web - incorporate interlinking food chains within an entire community A visual map showing feeding relationships and energy flow among organisms more complex than a food chain but greatly simplify community interactions and leave out most species The flow of energy and feeding relationships from lower to higher trophic levels is depicted in a food chain. Food webs incorporate all of the interlinking food chains within an entire community, showing the map of energy flow. Asian carp are predicted to affect the Lake Erie food web by decreasing the biomass of plankton-eating fish and their predators, while increasing the biomass of fish that can use juvenile carp for prey.

coral reefs

formed from the calcium carbonate skeletons of corals Shallow reef-building corals live in the warm, clear water Deepsea corals live at depths of 200-1,500 m Collection of coral skeletons, overfishing, global warming, pollution, and aquaculture are threats to coral reef ecosystems

population

group of organisms of one type that live in the same area

molecules

groups of atoms; smallest unit of most chemical compounds

what happens if there is low genetic diversity

inbreeding depression

benefits of industrialized agriculture

increases crop yields while reducing pressure to develop natural areas for new farms Has allowed food production to keep pace with population growth reduced starvation Increases crop yields while reducing pressure to develop natural areas for new farms

predation

interaction in which one species, the predator, kills and eats the other, the prey Some feeding adaptations of predators are claws, fangs, and poison Prey defensive adaptations may include Behavioral defenses (hiding, fleeing, forming herds or schools, self-defense, and alarm calls) Morphological and physiological defense adaptations (claws, fangs, and poison) Mechanical and chemical defenses (porcupines and skunks) Prey have a variety of adaptations to avoid predation Mechanical defenses Chemical defenses Cryptic coloration Aposematic coloration Mimicry (Batesian and Mullerian) look at 54.5 figure on ppt

community based conservation

is growing Developing nations often do not support conservationists from developed nations trying to preserve areas Biologists partner with local people to protect land and wildlife It offers education, health care, and development aid People are retrained to protect species Local resources can be sustainably managed

resource partitioning

is partitioning the ecological resource and utilizing a sub-set of the same resource, enabling similar species to coexist in a community Apparent competitors may actually have slightly different niches Species may use resources in a different way or time Minimizes competition and allows coexistence Competing species coexist by specializing

trophic feeding structure

is the feeding relationships between organisms in a community Food chains - Species in a community are given a rank within the feeding hierarchy Flow of energy and feeding relationships from lower to higher trophic levels is depicted

food security

is the guarantee of an adequate, safe, nutritious, and reliable food supply. Guarantee of an adequate, safe, nutritious, and reliable food supply When all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life (Committee on World Food Security, 2009) Providing food security to everyone will be one of our greatest challenges Physical, social, and economic access at all times to safe and nutritious food sufficient to meet dietary needs and food preferences for an active and healthy life.

parasitism

one organism, the parasite, derives nourishment from another organism, its host, which is harmed in the process unlike predation, usually does not result in an organism's death Endoparasites Ectoparasites relationship where one organism depends on the other for nourishment. Parasitism, unlike predation, usually does not result in an organism's death. Parasites live with their hosts in many ways: Inside the host, such as tapeworms. On the host's exterior, such as sea lampreys. Free-living, such as cuckoos, who lay their eggs in the nests of other species. Parasites and hosts adapt and counter-adapt to each other through a process called coevolution. The duel of escalating adaptations between parasites and hosts is known as an evolutionary arms race. Some parasites contact hosts infrequently, are free living and not symbiotic Cuckoos Cowbirds Goldeneye ducks

commensalism

one species benefits and the other is neither harmed nor helped

Struggle to Survive (Natural Selection)

only some organisms will survive - some with get caught with predators or get a disease

mass extinction events

ordovician - 444 million 85% extinct devonian - 370 million 83% extinct permian - 250 million 95% extinct triassic - 210 million 80% extinct cretaceous - 65 million 76% extinct quaternary - present 33-66%

parasitoids

organisms that lay eggs inside other organisms parasitize other organisms and kill the host Example: parasitic wasp Wasp larvae burrow into, and kill, caterpillars

grazing practices can contribute to soil degradation

overgrazing If livestock populations do not exceed the carrying capacity, rangelands can still be functional ecosystems. Without adequate regeneration of plant biomass, the result is overgrazing. Overgrazing exposes soil and makes it vulnerable to erosion. In a positive feedback loop, soil erosion makes it more difficult for native plants to grow, perpetuating the problem.

Biosphere

part of Earth in which life exists including land, water, and air or atmosphere - all ecosystems

intertidal zones

periodically submerged and exposed by the tides

interspecific interactions have evolutionary ramifications

predators better hunters Predators that are better at capturing prey will live longer, healthier lives; reproduce more, and take better care of offspring Natural selection leads to evolution of adaptations that make prey better at not being eaten/surviving They are at risk of immediate death They develop elaborate defenses against being eaten

prevention

prevent introduction or spread of exotic species rather than control, is the best policy Predicting where a species might spread is important Analyzing the biology of the organism allows scientists to model the environmental conditions they might thrive in.

conservation tillage

reduces the amount of plowing that would leave soil surfaces bare and exposed to wind reduces the amount of plowing, since it leaves soil surfaces bare and exposed to wind.

aquatic systems

shaped by: physical environment, chemical environment, geological features, photosynthetic organisms, and heterotrophs Freshwater and saltwater show less latitudinal variation than terrestrial biomes

cells

smallest unit of life

competitive exclusion principle

states that two species competing for the same limiting resources cannot coexist in the same place can lead to competitive exclusion - local elimination of a competing species Ecologically similar species can coexist in a community only if there are one or more significant differences in their niches Over many generations, natural selection may favor resource partitioning, where individuals use shared resources in different ways. No two species can occupy the same niche indefinitely when resources are limiting One will either migrate, become extinct, or partition the resource and utilize a sub-set of the same resource

regional differences in soil traits affect agriculture

swidden agriculture - Used in tropical areas after cultivation A plot is left to regrow into forest temperate prairies - Have lower rainfall and less nutrient leaching, resulting in higher fertility

exploitation

the action or fact of treating someone unfairly in order to benefit from their work. One member benefits while the other is harmed (/ interactions) Examples: predation, parasitism, herbivory In other types of interactions, some participants benefit while others are harmed. Predation, parasitism, and herbivory are exploitative interactions in which one participant benefits at the expense of another.

parent material

the base geologic material in a particular location. This may include: Hardened lava or volcanic ash. Sediment deposited by glaciers or flowing water. Wind-blown dunes. the base geologic material in a particular location. This may include: Hardened lava or volcanic ash. Sediment deposited by glaciers or flowing water. Wind-blown dunes. Bedrock, the mass of solid rock that makes up most of the Earth's crust.

bedrock

the mass of solid rock that makes up most of the Earth's crust.

habitat

the natural home or environment of an animal, plant, or other organism. includes living and nonliving elements

phase (regime) shift

the overall character of the community fundamentally changes the overall character of the community fundamentally changes Some crucial threshold is passed, a keystone species is lost, or an exotic species invades Example: overfishing and depletion of fish and turtles has allowed algae to dominate coral reef communities

habitat selection

the process by which organisms actively select habitats in which to live criteria: Food, shelter, breeding sites, and mates

group of cells

tissues, organs, and organ systems

facultative

where both species can survive alone

obligate

where one species cannot survive without the other

forensic science

can help protect species Analyzes evidence to identify or answer questions relating to a crime Conservation scientists use forensics to protect species at risk from illegal harvesting DNA identifies a species and its geographic origin Detecting illegal activity helps enforce laws protecting wildlife DNA from killed elephants shows many more were killed than the Zambian government realized

impacts of uncontrolled grazing

can result in overgrazing if stocking densities are too high grazing duration is too long and or grazing frequency is too often favors undesirable plant species can be destructive to the environment erosion deforestation desertification etc

ecosystem engineers or foundation species

cause physical changes in the environment that affect community structure Biodiversity increases the resilience of an ecosystem—its ability to withstand disturbance, recover from stress, or adapt to change. If a keystone species like a top predator is lost, consequences will cascade down the entire food chain. If an ecosystem engineer is lost, the entire structure of an ecosystem can change. The removal of elephants from some of Africa's savannas has caused scrubby vegetation to overgrow, turning them into scrub forests.

evolution

change over time

interspecific

competition takes place between members of different species.

intraspecific

competition takes place between members of the same species.

marine benthic zone

consists of the seafloor Organisms in the very deep are adapted to continuous cold and extremely high water pressure Mainly soft sediments; some areas are rock Deep-sea hydrothermal vents of volcanic origin on mid-oceanic ridges have abundant life Overfishing and dumping of waste have depleted fish populations

no till drill

cuts furrow, drops in a seed, closes furrow over seed Cuts furrow Drops in a seed Closes furrow over seed Critics of no-till farming Argue that it requires more use of chemical herbicides Proponents Point out that many farmers rely more heavily on green manures to fertilize and cover crops to choke out weeds Can improve soil quality and store carbon in soils (combating global climate change)

respond to invasive species with

eradication control prevention Eradication of an invasive species is extremely difficult, so managers aim to control populations. Since the 1990s, federal funding has been provided for control measures: Netting juvenile fish, contracting fishermen to catch adults, bubbling carbon dioxide into the water, and broadcasting noise into the water Control and eradication have been very expensive, so now attention is given to preventing future invasions.

shelterbelts

(windbreaks) Rows of trees and shrubs planted along edges of fields Slows the wind Can be combined with intercropping are rows of trees or shrubs that serve as windbreaks. The trees can also provide habitats and fruit.

biome

- A regional complex of similar communities Terrestrial biomes are classified primarily by dominant plant type and vegetation structure, which in turn is the result of climate Despite communities being in very different locations in the Earth, they often have similar structure and function. A regional complex of similar communities is called a biome. Biomes are classified primarily by dominant plant type and vegetation structure, which in turn is the result of climate.

ectoparasites

- Parasites that live on the external surface of a host live on exterior of host Fleas, ticks, mites, lice, Mosquito Sea lampreys Mistletoe, orchids, bromeliads

compost

- produced when decomposers break down organic matter in a controlled environment

soil erosion

- removal of material from one place to another by wind or water Deposition - arrival of eroded material at a new place These are natural processes, but are occurring at accelerated rates due to several widespread practices A problem when it happens faster than soil formation A problem because if removes topsoil at faster rates, quickly depleting soil of nutrients and organic matter. Areas that are windy, are sloped, have intense precipitation, or have sparse vegetative cover are the most at risk of erosion Industrial agriculture Overcultivating fields: poor planning, excessive tilling Overgrazing rangeland with too many animals Clearing forests or vegetation on steep slopes or with large clear-cuts the removal of material from one place and its transport to another by wind or water. When eroded material is left at a new location, it is called deposition. Erosion and deposition are natural processes, but are occurring at accelerated rates due to agriculture. This removes topsoil at faster rates, quickly depleting soil of nutrients and organic matter. Areas that are windy, are sloped, have intense precipitation, or have sparse vegetative cover are the most at risk of erosion. A problem when it happens faster than soil formation People make land more vulnerable to erosion with several widespread agricultural practices: Overcultivating fields through poor planning or excessive tilling (plowing). Grazing rangeland with more livestock than it can support. Clearing forests on steep slopes. One study determined that U.S. croplands lose about2.5 cm (1 in.) of topsoil every 15-30 years.

introduced species may alter communities

- species that humans move from their native locations to new geographic regions Without their native predators, parasites, and pathogens, introduced species may spread rapidly (invasive species) Introduced species that gain a foothold in a new habitat usually disrupt their adopted community (invasive species) Introduced species are non-native arrivals to a community brought by people. Most fail to establish populations, but the ones that thrive are called invasive species. Introduced species become invasive when limiting factors that normally regulate their population growth are absent. Lack of competition, predators, or parasites.

locally supported agriculture is growing

"Think global, eat local" Sustainable agriculture reduces fossil fuel use from long-distance transport of products The average food product sold in a U.S. supermarket travels at least 1600 km (1000 mi) from the farm Farmers' markets consumers buy meats and produce from local producers Provide fresh, locally grown food Provide organic items and unique local varieties Community-supported agriculture (CSA) Consumers pay farmers in advance for a share and then receive weekly deliveries of produce Consumers get fresh food and farmers get a guaranteed income

case study: saving hawaiis native forest birds

'akiapōlā'au ("aki" for short) Sparrow-sized honeycreeper birds that exist only on the Hawaiian Islands Human actions now threaten native species of flora and fauna Cutting down trees Introducing non-native animals Foreign disease spread to the islands Refuge managers and conservation biologists Work hard to protect the Hakalau's forests.

feedlots

(factory farms) Also called concentrated animal feeding operations (CAFOs) Huge warehouses or pens deliver food to animals living at extremely high densities Produce over half of the world's pork and most of its poultry are huge pens designed to provide high-energy feed to animals living in high densities. These are also known as factory farms or confined animal feeding operations (CAFOs). Feedlots have the benefit of being more economically efficient and reducing grazing impacts by the animals.

4 parts of natural selection

1. Overproduction, 2. Variations, 3. Adaptations, 4. Descent with Modification

public debate over gm food continues

A big part of the public debate is that every person relies on food for survival and genetic modification of rice, corn, soy, and wheat essentially forces people to consume biotech products Another concern is that a few large companies such as Monsanto, Bayer, Dow, DuPont, and BASF control GM technology These companies patent their seeds, meaning that if a farmer's crops are pollinated by a neighbor's GM crops, he may be sued for harvesting and replanting his own seeds Most biotech crops so far have been engineered for insect resistance and herbicide tolerance, primarily benefiting large-scale industrial farmers and not poor rural ones.

Ecosystem

A biological community of interacting organisms and their physical environment. also nonliving surroundings

resilience

A community changes in response to a disturbance, but later returns to its original state

resistance

A community resists change and remains stable despite the disturbance

Soils

A complex system consisting of disintegrated rock, organic matter, water, gases, nutrients, and microorganisms Soil is derived from rock, but shaped by microorganisms 50% mineral matter, 5% organic matter, and 45% pore space. Dead and living microorganisms Decaying material Bacteria, fungi, worms, insects, burrowing animals A renewable resource that can be depleted if abused Soil influences ecosystems as much as climate, latitude, and Soil formation begins during primary succession, as water, air, and living organisms break down parent material in the lithosphere. parent material bedrock weathering Soil is renewable, but at a very slow rate.

overproduction

A condition in which production of goods exceeds the demand for them

secondary succession

A disturbance has removed much, but not all, of the biotic community Fires, hurricanes, logging, farming, overgrazing

primary succession

A disturbance removes all plant or soil life Glaciers, drying lakes, volcanic lava covering the land begins with the colonization of pioneer species Pioneer species - The first species to arrive in a primary succession area Lichens: fungi algae Severe disturbances may eliminate all or most of the species in a community, initiating a series of changes called succession. Succession begins with the colonization of pioneer species. Pioneer species, such as grasses and forbs, spread over long distances easily and are adapted for growing quickly. Over time, pioneers are overtaken by longer-living climax community species, such as hardwood trees.

food web

A food web is a branching food chain with complex trophic interactions Incorporate all of the interlinking food chains within an entire community, showing the map of energy flow. The flow of energy and feeding relationships from lower to higher trophic levels is depicted in a food chain. Food webs incorporate all of the interlinking food chains within an entire community, showing the map of energy flow. Asian carp are predicted to affect the Lake Erie food web by decreasing the biomass of plankton-eating fish and their predators, while increasing the biomass of fish that can use juvenile carp for prey.

sustainable agriculture begins with soil management

A number of approaches have been implemented since the Dust Bowl to alleviate soil degradation crop rotation contour farming terracing intercropping shelterbelts conservation tillage no till farming no till drill

Species

A population or populations whose members share characteristics and can breed with each other to produce fertile offspring

conservation biology

A scientific discipline devoted to understanding factors, forces, and processes that influence the loss, protection, and restoration of biological diversity Study our impacts on other organisms and on environmental systems Design, test, and implement responses to these impacts

species

A set of individuals that share certain characteristics and can interbreed producing fertile offspring

introduced species

A species introduced to a community by people Introduced deliberately or accidentally Introduced species are non-native arrivals to a community brought by people. Most fail to establish populations, but the ones that thrive are called invasive species. Introduced species become invasive when limiting factors that normally regulate their population growth are absent. Lack of competition, predators, or parasites.

keystone species

A species that influences the survival of many other species in an ecosystem can include: Decomposers that recycle nutrients and replenish the soil. "Ecosystem engineers," such as beavers and prairie dogs, who physically alter ecosystems. Top predators, who control populations of lower trophic level consumers, are often keystone species A species that has an impact far greater than its abundance exert strong control on a community by their ecological roles, or niches Have effects even when not in large abundance Removing a keystone species has substantial ripple effects and alters the community

unity in the diversity of life

A striking unity underlies the diversity of life DNA is the universal genetic language common to all organisms Living things are all made up of cells Unity is evident in many features of cell structure Unity is evident in that the forelimb of the human, cat, horse, whale flipper, and bat wing all share a common skeletal architecture

fossil

A trace of an ancient organism that has been preserved in rock.

organic agriculture is booming

About 80% of Americans buy organic food at least occasionally, and most retail groceries offer it Both production and demand for organic foods have grown, with some governments offering financial incentives to convert to organic agriculture

observation #1

All species can produce more offspring than the environment can support, and many of these offspring fail to survive and reproduce

tropical dry forest

Also called tropical deciduous forest Plants drop leaves during the dry season Wet and dry seasons Warm, but less rainfall Converted to agriculture Severe soil erosion Tropical dry forests have wet and dry seasons that each occupy about half of the year. Temperature is consistently warm. Leaves are shed during the dry season.

community

An assemblage of populations of organisms living in the same area at the same time interacting with each other Interactions determine the structure, function, and species composition of the community Community ecologists study which species coexist, how they interact, how communities change over time, and why these patterns occur. Some of the most important interactions among community members involve who eats whom. Species in a community are given a rank within the feeding hierarchy, called a trophic level. Producers use photosynthesis or chemosynthesis to make their own sugars. Primary consumers consume producers.

organism

An individual living thing

transgenic organism

An organism that contains DNA from another species Transgenes - genes that have moved between organisms An organism that contains DNA from another species is called a transgenic organism. The genes that move between them are called transgenes. To create recombinant DNA, scientists follow several steps.

niche

An organism's functional role in a community

pests

Any organism that damages crops / livestock Industrial monocultures limit the ability of natural enemies to control pest populations, causing farmers to turn to chemical suppression.

weeds

Any plant that competes with crops Industrial monocultures limit the ability of natural enemies to control pest populations, causing farmers to turn to chemical suppression.

genetic engineering

Any process where scientists directly manipulate an organism's genetic material (DNA) Laboratory manipulation of genetic material by adding, deleting, or modifying DNA Goal of genetic engineering Put genes that code for desirable traits (rapid growth, nutrition, etc.) into organisms lacking those traits refers to any process where scientists directly manipulate an organism's genetic material (DNA).

chaparral

Densely thicketed, evergreen shrubs Highly seasonal biome Mild, wet winters Warm, dry summers densely thicketed shrubs, small trees, grasses, and herbs many plants adapted to and resistant to fire and drought Chaparral is only found in a few small patches throughout the world. Covered by a dense thicket of evergreen shrubs. Mild, wet winters and warm, dry summers. Fires are frequent. Climate is induced by nearby oceans. hollywodd/ca

ecological niche

Description of the role a species plays in a biological community, or the total of all the ways an organism uses the biotic and abiotic resources of its environment Generalists - Broad niche Specialists - Narrow niche The alteration of ecosystems creates "winners" and "losers" among the world's animals and plants. Humans have a tendency to change ecosystems so that they are more similar to each other, more open in structure, and more polluted. This favors generalists, which can adapt to the changing conditions, and harms specialists, which rely on mature, stable ecosystems.

genetic diversity

Differences in DNA among individuals Provides the raw material for adaptation to local conditions Natural selection cannot lead to evolution or adaptation if all individuals in a population are exactly the same

divergent evolution

Divergent evolution Selective pressures among closely related species cause them to acquire different traits Evolution towards different traits in closely related species Can lead to speciation Selective pressures among closely related populations cause them to acquire different traits the accumulation of differences between these groups can lead to the formation of new species

green revolution and population growth

Do you think the Green Revolution has solved problems, deferred problems, or created new ones? Which aspects of the Green Revolution do you think help in the quest for sustainability, which do not, and why? Have the benefits of the Green Revolution outweighed its costs?

green revolution

Drastically increased food through new: Technology Crop varieties (wheat, rice, corn) Farming practices Spread to the developing world in the 1940s Began with Norman Borlaug, a Nobel Prize-winning scientist who introduced new strains of wheat to Mexico, India, and Pakistan Beginning in 1940, the Green Revolution introduced new technology, crop varieties, and farming practices to the developing world. Began with Norman Borlaug, a Nobel Prize-winning scientist who introduced new strains of wheat to Mexico, India, and Pakistan The Green Revolution helped to increase yields and reduce starvation, but has also degraded soil, water supplies, and pollinators.

endangered species act

ESA (1973) The primary legislation for protecting biodiversity in the U.S. Forbids the government and citizens from taking actions that destroy endangered or threatened species as well as their habitats Forbids trading in products made from these species Aim is to prevent extinction, stabilize declining populations, and enable populations to recover In 2014, recovery plans were in place for 75% of the 1189 endangered and 328 threatened species in the U.S. Intensive management has saved or stabilized species 40% of declining populations have been stabilized Bald eagle, peregrine falcon, and brown pelican have been removed from the endangered list Recent successes have occurred despite problems Underfunding of the U.S. Fish and Wildlife Service and the National Marine Fisheries Service Recent political forces have tried to weaken the ESA

our food choices are also energy choices

Eating meat is far less energy-efficient than eating crops 90% of energy is lost from one trophic level to the next Some animals convert grain into meat (or eggs or milk) more efficiently than others Eating lower on the food chain (a more vegetarian diet) is more energy-efficient and reduces our ecological footprint. Every time that one organism consumes another, only about 10% of the energy moves to the next trophic level. Feeding grain to a cow and eating beef from the cow result in loss of most of the grain's energy to the cow's metabolism. Eating lower on the food chain (a more vegetarian diet) is more energy-efficient and reduces our ecological footprint.

Biodiversity provides ecosystem services

Ecosystem services - all the processes through which natural ecosystems and their species help sustain human life Biodiversity Captures solar energy Provides food, fuel, fiber, and shelter Purifies air and water Detoxifies and decomposes wastes Cycles nutrients, forms soil, renews soil fertility Pollinates plants Controls pests and disease Stabilizes climate Moderates floods, droughts, temperature Maintains genetic resources Allows life (us) to adapt to change Provides cultural and aesthetic benefits all the processes through which natural ecosystems and their species help sustain human life all these services depend on biodiversity Can a system function without all its integral parts? If we lose biodiversity are we risking or losing these vital services that sustain human life? ~$33 trillion global value/year

biodiversity boots economies through tourism and recreation

Ecotourism is a vital source of income for many nations Costa Rica: rainforests Australia: Great Barrier Reef Belize: reefs, caves, and rainforests U.S.: national parks Kenya and Tanzania: savanna wildlife A powerful incentive to preserve natural areas and reduce impacts on wildlife and landscapes Americans spend ~$104 billion annually on wildlife-related recreation But too many visitors can damage natural assets

no till farming

Eliminates tilling altogether Ultimate form of conservation tillage Farmers leave crop residues behind, keeping the soil covered with plant material year-round Residues of previous crops are left in field to prevent erosion Soil soaks up more water cover crops can be planted during times when the main crop is not growing eliminates tilling altogether. Farmers leave crop residues behind, keeping the soil covered with plant material year-round. Temporary cover crops can be planted during times when the main crop is not growing. Critics of no-till farming in U.S. Argue that it requires more use of chemical herbicides Proponents Point out that many farmers rely more heavily on green manures to fertilize and cover crops to choke out weeds Can improve soil quality and store carbon in soils (combating global climate change)

human manipulation of earths climate

Emission of greenhouse gases warms temperatures Modifies global climate patterns Increases the frequency of extreme weather events Increased stress forces organisms to shift their geographic ranges Many species will not be able to adapt A temperature increase of 1.5-2.5°C threatens 20-30% of species with extinction

energy numbers and biomass decrease at high trophic levels

Energy decreases at higher trophic levels At each trophic level, most of the energy input is either used for maintenance or lost as heat. Most energy that organisms use in cellular respiration is lost as waste heat At each trophic level, most of the energy input is either used for maintenance or lost as heat. Most energy that organisms use in cellular respiration is lost as waste heat Less and less energy is available in each successive trophic level Each trophic level contains only 10% of the energy of the trophic level below it Biomass is the collective mass of living matter in a given place and time. The pyramid pattern of energy and biomass illustrates why eating at lower trophic levels decreases your ecological footprint.

energy passes among trophic levels

Energy moves through the community Matter cycles within the community Trophic levels Producers (autotrophs) Consumers (heterotrophs) Detritivores and decomposers (heterotrophs) Species in a community are given a rank within the feeding hierarchy, called a trophic level. Producers use photosynthesis or chemosynthesis to make their own sugars. Primary consumers consume producers.

conservation reserve program

Every 5-6 years, the U.S. Congress passes legislation called the Farm Bill that guides agricultural policy Conservation Reserve Program (1985) pays farmers to convert damaged or poorly suited cropland to conservation reserves. Trees and grasses are planted instead of crops Each dollar spent saves 1 ton of topsoil Generates income for farmers Improves water quality Provides habitat for wildlife $1.8 billion/year protects 27 million acres The 2014 Farm Bill limits protection to 24 million acre International programs led by Food and Agriculture Organization (FAO) Every 5-6 years, the U.S. Congress passes legislation called the Farm Bill that guides agricultural policy. The Conservation Reserve Program, first established in the 1985 Farm Bill, pays farmers to convert damaged cropland to conservation reserves.

understanding evolution

Evolutionary processes influence agriculture, pesticide resistance, medicine, health, etc. Understanding and application of evolutionary processes play a key role in our everyday lives Food we eat Clothes we wear Many medical advances Preventing antibiotic resistance Pesticide resistance in crop-eating insects Even technology and engineering solutions have developed as a result of our understanding of evolution

endemic species

Exists only in a certain, specialized area Geographically isolated Very susceptible to extinction Populations are usually small the ecological state of a species being unique to a defined geographic location, such as an island, nation, country or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere.

concerns over gm foods

Expensive Little incentive to develop crops for small-scale farmers Most biotech crops so far have been engineered for insect resistance and herbicide tolerance, primarily benefiting large-scale industrial farmers and not poor rural ones a few large companies control GM technology Monsanto, Bayer, Dow, DuPont, and BASF These companies patent their seeds, meaning that if a farmer's crops are pollinated by a neighbor's GM crops, he may be sued for harvesting and replanting his own seeds Many experts think we should follow the precautionary principle and proceed with caution on GM foods Many people think that "tinkering" with food supply is dangerous or morally wrong Others fear that global food supply is dominated by large corporations that develop GM technologies Agrobiotech corporations have taken out patents on transgenes Ecological impacts of GM foods pose the greatest threat Ecologically, scientists are concerned that GMOs will interbreed with their wild relatives transferring new genes into the wild population Some feel we should adopt the precautionary principle and not proceed further until the effects of GM crops are fully understood GM oilseed rape was found hybridizing with wild mustard Creeping bentgrass engineered for golf courses has pollinated wild grass up to 21 km away

data question

Explain how the percentage of undernourished people decreased from 2007-2009 to 2010-2012 while the absolute number of undernourished people stayed roughly the same

landscape ecology

Explains how and why ecosystems, communities, and populations are distributed across geographic regions

background extinction rate

Extinction is a natural process that occurs very slowly Background extinction rate Natural extinctions For mammal or marine species, each year 1 species out of every 1-10 million goes extinct 99% of all species that ever lived are now extinct The current extinction rate is 100 to 1,000 times greater than the background rate Due to human population growth and resource consumption

Background and mass extinction

Extinction usually occurs slowly, one species at a time Killed off massive numbers of species at once Fossil record reveals five of these events in Earth's history 50-95% of all species went extinct each time Best-known event occurred 65 million years ago A gigantic asteroid caused dinosaur extinction 250 million years ago 75-95% of species went extinct from unknown causes

benefits and risks of organic farming

Farmer benefits Lower input costs Enhanced income (higher value products) Reduced chemical pollution and soil degradation Farmer risks Organic approaches must be used for 3 years before products become certified and sold at higher prices Obstacle for consumers Higher price for organic food, but many are willing to pay the price Worldwide, sales surpassed $63 billion

community ecology

Focuses on patterns of species diversity and interactions

biodiversity and human welfare

Food drugs and medicine tourism biophilia ecosystem services

humus

Further biological activity deposits organic matter in the form of decomposed organisms or waste. Partially decomposed organic matter is called humus and is very productive for plant life.

Biotechnology is transforming the products around us

GM crops today are engineered to resist: Herbicides Insect attack In U.S. today: 90% of corn, soybeans, cotton, and canola consist of genetically modified strains Worldwide: GM crops have been adopted and planted around the world 4 out of 5 soybean and cotton plants are now transgenic 1 out of 3 corn and canola plants 70% of processed foods in U.S. stores contain GM ingredients Sales of GM seeds have increased in the United States and other countries. Soybeans account for more than half of the GM crops grown worldwide. The United States, Brazil, Argentina, India, and Canada accounted for 90% of production in 2017.

what are the potential benefits of gm foods

GM foods can advance sustainable agriculture Grown with no-till farming Drought resistant and high-yielding they can: Enhance food security and reduce poverty Alleviate pressure to clear forests and grasslands Conserve water by reducing the need for irrigation Improve nutrition with crops that contain key nutrients (such as golden rice and vitamin A) Reduce pesticide use

natural selections acts on genetic variation

Genes in DNA are passed along to future generations Mutations Accidental changes in DNA that may be passed to the next generation Nonlethal mutations provide genetic variation on which natural selection acts Sexual reproduction also leads to genetic variation Producing new combinations of genes

biological evolution

Genetic change in populations over time Genetic changes often lead to modifications in appearance or behavior One of the best-supported and most illuminating concepts in science It is the foundation of modern biology "Nothing in biology makes sense except in the light of evolution" —Theodosius Dobzhansky

restoration ecologists return degraded ecosystems to a more natural state

Given enough time, biological communities can recover from many types of disturbances Ecological restoration seeks to initiate or speed up the recovery of degraded ecosystems The long-term objective of restoration is to return an ecosystem as much as possible to its pre-disturbance state Scientists who study restoration ecology devise ways to restore altered areas to their condition before industrialized civilization. Ecological restoration can have two aims: Restore the functionality of an ecosystem Return a community to its "pre-settlement" condition A good example is the U.S. tallgrass prairie, much of which had been removed for farmland. A 1000-acre area near Chicago has been restored with native vegetation.

global change

Global change - alterations in climate, atmospheric chemistry, and broad ecological systems Pollution Acid precipitation contains sulfuric acid and nitric acid from the burning of wood and fossil fuels Climate Change

climate change

Global climate change now threatens conservation biology efforts Change in temperatures alters many aspects of the environment The protected areas may become unsuitable for the species being protected Scientists and managers need to come up with new ways to help save declining populations

habitat fragmentation

Gradual, piecemeal degradation and loss of habitat Farming, logging, roads, etc. Continuous habitats are broken into patches Species needing continuous habitat disappear

crop rotation

Growing different crops from one season to the next Returns nutrients to soil Prevents erosion, reduces pests Wheat or corn and soybeans Alternating with legumes can boost soil nitrogen, and crop rotation also break pest and disease cycles associated seen with continuous planting A number of approaches have been implemented since the Dust Bowl to alleviate soil degradation. Crop rotation is the process of farmers alternating the type of crop grown from one season to the next. Alternating with legumes can boost soil nitrogen, and crop rotation also breaks pest and disease cycles seen with continuous planting.

drawbacks to industrialized agriculture

Has many bad environmental and social effects Degraded soil, water supplies and pollinators Water, fossil fuels, fertilizers, and pesticides worsen pollution, erosion, and desertification Requires far more energy than traditional methods Displaces low-income farmers who can't afford the technology, forcing them to move to cities

habitat loss

Human alteration of habitat is the greatest threat to biodiversity In almost all cases, habitat fragmentation and destruction lead to loss of biodiversity

conservation biodiversity

Human development, resource extraction, and population pressures are speeding up the rate of environmental change Committed people are taking action to: Safeguard biodiversity Restore Earth's ecological and evolutionary processes

the 6th mass extinction is upon us

Humans are causing the sixth mass extinction event Population growth, development, resource depletion Altering and destroying natural habitats Overhunting and overharvesting populations Polluting air, water, and soil Introducing invasive non-native species Biodiversity loss affects humans We need organisms for food, fiber, medicine, services

soil erosion is a global problem

Humans are the primary cause of erosion It is occurring at unnaturally high rates Human activities move over 10 times more soil than all other natural process World's croplands - over 47 billion acres affected by erosion/soil degradation United States loses 5 metric tons of soil for every ton of grain harvested One study determined that U.S. croplands lose about2.5 cm (1 in.) of topsoil every 15-30 years.

human disturbance

Humans have the greatest impact on biological communities worldwide Both terrestrial and marine ecosystems are subject to human disturbance Human disturbance to communities usually reduces species diversity Severely degraded systems cease to function

Darwin and Wallace

In 1858, both Darwin and Wallace proposed natural selection as the mechanism of evolution Darwin made two main points Species showed evidence of "descent with modification" from common ancestors "Natural selection" is the mechanism behind descent with modification Darwin's theory explained duality of unity and diversity

dust bowl

In late 1800 and early 1900, farmers and ranchers: Grew wheat, grazed cattle Removed native grasses Dust Bowl 1930s drought worsened erosion, caused "black blizzards" of soil Thousands of farmers were forced to leave their land Relied on governmental help to survive In the late 19th and early 20th centuries, farmers moving into the Western Plains of the United States began plowing up native grassland plants in favor of wheat. A severe drought in the 1930s worsened the impacts, causing the region's strong winds to erode millions of tons of topsoil. Some areas in the most affected regions of the Dust Bowl lost 10 cm (4 in.) of topsoil in just a few years. Thousands of farmers in this area were forced off their land.

inbreeding depression

In small or isolated populations with low genetic diversity, genetically similar parents mate and produce weak, defective, or inferior offspring American bison, elephant seals, and cheetahs are examples Domestic dog breeds, past royal families, past amish societies ex: northern elephant seal population fell to about 30 in the 1890s. American bison before 1492 was ~60 million, in 1890 was 750, in 2000 350,000 Before Europeans arrived in North America, prairies served as habitats to greater prairie chickens. In Illinois alone their numbers plummeted from over 100 million in 1900 to about 50 in 1990. These declines in population were the result of hunting and habitat destruction, but the random consequences have been a great loss in species diversity. DNA analysis comparing the birds from 1990 and mid-century shows a steep genetic decline in recent decades. The greater prairie chicken is currently experiencing low reproductive success.[11]

case study: asian carp

In the 1960s and 1970s, managers of catfish farms and wastewater treatment plants began importing carp from Asia to clean up infestations of algae and snails. Some of these individuals escaped into nearby streams, rivers, ponds, and lakes, The Asian carp have been very successful, growing too large for predators to capture and spreading throughout the Mississippi River Valley. As these carp advanced up the Illinois River, people have become concerned that the carp would invade the Great Lakes. An electric barrier is now in place to try to stop Asian carp from reaching the Great Lakes. The Great Lakes have already become host to 180 non-native species, such as zebra mussels. Zebra mussels, introduced through the ballast water of ships, cause hundreds of millions of dollars in damage annually by clogging pipes, covering boat propellers, outcompeting native mussels, and transforming fisheries. What further impacts could the Asian carp have on the Great Lakes? Answering this question requires a knowledge of how each of the populations in the Great Lakes interact with each other.

drugs and medicines

In the United States, 25% of prescriptions contain substances originally derived from plants Pharmaceutical companies actively prospect tropical countries for products For example, the rosy periwinkle contains alkaloids that inhibit cancer growth

integrated pest management combines varied approaches to pest control IPM

Incorporates numerous techniques to suppress pests, including: Close monitoring of pest populations Biocontrol Synthetic chemical use when needed Habitat alteration Crop rotation Transgenic crops Alternative tillage methods Mechanical pest removal IPM in Indonesia increased rice yields and eliminated subsidy payments and decreased pesticide use combines biocontrol, chemical pesticides, habitat alteration, crop rotation, transgenic crops, alternative tillage methods, and mechanical pest removal. This has been highly effective in Indonesia, which increased rice production while cutting pesticide subsidies and overall pesticide use.

interspecific interactions drive population dynamics

Increased prey populations increase food for predators Predators survive better and reproduce more Increased predator populations decrease prey Predators starve and their populations decrease Decreased predator populations increase prey populations

captive breeding

Individuals are bred and raised so they can be reintroduced into the wild Reintroductions can be resource-intensive

premises of natural selection

Individuals of a population produce more offspring than can survive (overproduction) Individuals of a population vary in their characteristics because of genes (inherited variation) and the environment Organisms struggle to survive and reproduce Some individuals are better suited to their environment and reproduce more effectively Selection acts on genetic variation Genes in DNA are passed along to future generations

inference #1

Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than other individuals 1. population with varied inherited traits 2. elimination of individuals with certain traits 3. reproduction of survivors 4. increasing frequency of traits that enhance survival

natural selection summary

Individuals with certain heritable traits survive and reproduce at a higher rate than other individuals Natural selection increases the match between organisms and their environment over time If an environment changes over time, natural selection may result in adaptation to these new conditions and may give rise to new species Natural selection results in the adaptation of organisms to their environment Adaptations (adaptive traits) Characteristics that promote reproductive success

biodiversity enhances food security

Industrial agriculture has narrowed our diet 90% of our food comes from 15 crop and 8 livestock species Wild and rare species can improve food security Crop ancestors hold reservoirs of genetic diversity They can save monocultures through crossbreeding or genetic engineering Wild strains provide disease resistance New potential food crops are waiting to be used

seed banks conserve wild genes

Industrial agriculture's use of genetically similar crops (monocultures) has led to efforts to conserve wild relatives of crops Wild crops contain genes we will need in the future Seed banks Institutions that store seed types Seeds are collected, stored, and periodically planted

what are the potenital disadvantages of gm foods

Insecticide use declined, but herbicide use increased Although insecticide use is decreasing, herbicide use is growing because many weeds are developing resistance to herbicides, spurring farmers to apply even more.

interspecific interations affect the community

Interactions between predators and prey, herbivore and plant, parasite and host... structure food webs influence community composition can be complex and changing predators can also become prey

invasive species cause biodiversity loss

Introduction of non-native species to new areas Accidental: zebra mussels, exotic pets, weeds Intentional: food crops, exotic pets, plants Invaders lack predators, parasites, or competitors Displace native species

population ecology

Investigates population changes The distribution and abundance of individuals Why some populations increaseand others decrease

supplementing water and nutrients to boost crop yields can affect natural systems near and far

Irrigation boosts productivity but can damage soil Waterlogging Salinization

some organisms play outsized roles

Keystone species A species that has an impact far greater than its abundance A species that has an impact far greater than its abundance is called a keystone species. Keystone species can include: Decomposers that recycle nutrients and replenish the soil. "Ecosystem engineers," such as beavers and prairie dogs, who physically alter ecosystems. Top predators, who control populations of lower trophic level consumers, are often keystone species.

our food choices are also energy choices

Land and water are needed to raise food for livestock Eggs and chicken meat require the least Producing beef requires the most When we choose what to eat, we choose how we use resources such as land and water Based on these difference in energy conversion efficiencies, a footprint of land area, water weight, and CO2 equivalents has been calculated for producing 1 kg of edible protein for each animal. Animal agriculture accounts for 14.5% of our greenhouse gas emissions—more than driving. As wealth and commerce increase, so does consumption of meat, milk, eggs and other animal products Since 1950, global meat production has increased more than fivefold, and per capita meat consumption has doubled Meat consumption is expected to double again by 2050 as more nations go through the demographic transition and become wealthier As global wealth and commerce have increased, so have the production and consumption of meat, milk, eggs, and other animal products. Meat production has grown more than fivefold since 1950, and per capita meat consumption has doubled.

terracing

Level platforms cut into steep hillsides This "staircase" contains rain and irrigation water a similar idea, where the creation of level platforms on very steep terrain slows water erosion.

control

Limit growth, spread, and impact of a population Control and eradication are difficult and expensive

biodiversity hotspots

Locations around the world that are characterized by exceptional levels (a great concentration) of endemic species and critical levels of habitat loss endemic species - species found nowhere else in the world The area must have at least 1500 endemic plant species (0.5% of the world total) It must have lost 70% of its habitat as a result of humans' impact Results in many endangered and threatened species An international approach oriented around geographic regions Biodiversity hot spots are good choices for nature reserves but identifying them is not always easy designation of hot spots is often biased toward saving vertebrates and plants Hot spots can change with climate change Focusing on biodiversity hotspots protects the greatest number of species per unit effort 2.3% of the land surface contains 50% of all plant species and 42% of all terrestrial vertebrate species

soil degradation

Loss of soil quality and productivity Has caused 13% loss of grain production in last 50 years We lose 12-17 million acres of productive cropland to degradation each year but may gain another billion people in the next decade or two

organisms provide drugs and medicines

Many drugs come from wild plants Wild species produce up to $150 billion/year of drugs that save thousands of lives

agriculture subsides affect soil degradation

Many nations spend billions to subsidize agriculture 20% of a U.S. farmer's income comes from subsidies Pros of subsidies help to stabilize and secure the income of farmers Cons of subsidies Encourages farming of vulnerable or incompatible land Artificially increases food production, driving prices down Lead to land being cultivated that otherwise would not be Critics propose that instead of relying on subsidies, farmers should buy insurance against losses Many nations spend billions in subsidies to promote unsustainable practices, such as growing water-thirsty crops in desert regions. In the United States, one-fifth of an average farmer's income comes from subsidies. Subsidies help to stabilize and secure the income of farmers, but they also lead to land being cultivated that otherwise would not be. This artificially increases food production, lowering prices for other farmers.

Do we have ethical obligations toward other species?

Many people feel that other organisms have an inherent right to exist "If species aren't worthy of saving, then what are we all about? What is worth saving?" As more people take up biocentric or ecocentric worldviews, more have come to feel that other organisms have an intrinsic value Biodiversity conservation is justified on ethical grounds

sustainable approaches to irrigation maximize efficiency

Match crops and climate Don't plant crops that require large amounts of water in arid climates Plant beans or wheat, not rice, almonds, pistachios, alfalfa New technologies improve water use efficiency Instead of flood-and-furrow irrigation, drip irrigation can increase efficiencies to over 90% One effective way to reduce water use is to better match crops and climate. Government subsidies in some arid areas have made water artificially inexpensive. Plants only use about 40% of the water applied by irrigation on average. Switching to drip irrigation can also reduce water use.

observation #2

Members of a population vary in their inherited traits

inorganic fertilizers

Mined or synthetically manufactured mineral supplements urea, ammonium sulfate, calcium nitrate mined potash, phosphate rock, and lime

leaching

Minerals dissolved or suspended in water can be transported downward in a process called leaching

desert

Minimal precipitation Temperatures vary widely Day vs. night, seasonally Soils (lithosols) High mineral content, low organic matter Residents have adaptations for water conservation and resistance to heat Animals - Nocturnal, nomadic Plants - Thick skins, spines Deserts are the driest biome, receiving less than 25 cm of rain per year. Soils have high mineral and low organic matter content. Animals and plants must adapt to minimize water loss. arizona

tundra

Minimal rain, very cold harsh winters, cool summers Permafrost Permanently frozen soil Residents Polar bears, musk oxen, migratory birds, caribou Lichens, low vegetation, no trees Alpine tundra On mountaintops Tundras are also very dry, but are consistently cold all year. Underground soil is permanently frozen, called permafrost. Tundras are unoccupied by humans, but are the most directly impacted by air pollution and climate change. alaska

a mix of causes threatens many species

Monarch butterfly populations are declining Industrial agriculture has eliminated most of milkweed plants that monarchs depend on Pesticides intended for crop pests also kill monarchs In Mexico, the forests monarchs migrate to are being illegally logged Worldwide collapse of amphibians Entire populations of frogs, toads, and salamanders are vanishing Over 40% of 7200 known species of amphibians are in decline and 30% are threatened At least 170 species studied just a few years or decades ago are extinct

temperate grasslands

More temperature difference between winter and summer Less precipitation supports grasses, not trees Also called steppe or prairie Animals include bison, prairie dogs, pronghorn, ground-nesting birds Once widespread, but has been converted to agriculture Temperature differences between winter and summer are more extreme and rainfall diminishes in temperate grasslands. These biomes are also known as prairie or steppe.

threats to biodiversity

Most species loss can be traced to five major threats Habitat loss Pollution Overharvesting Invasive species Climate change

invasive species

Non-native species that spreads widely and becomes dominant in a community Growth-limiting factors are absent (no predators, disease, competitors, etc.) Cause major ecological effects

habitat use

Nonrandom patterns where organisms live

pollination

Not all insects are pests; some are absolutely vital Over 800 cultivated plants rely on pollinators Pollination - Male plant sex cells fertilize female sex cells Flowers are evolutionary adaptations to attract pollinators Nectar, pollen, sweet smells, bright colors When trying to control "bad" bugs, we must be very careful not to kill the "good" insects that aid us in agriculture and are an essential link in the food web of many organisms process by which male plant sex cells (pollen) fertilize female plant sex cells (ova, or egg cells). Grasses and conifer trees are pollinated by wind. Plants with bright flowers attract animals (pollinators), which transfer pollen as they move from flower to flower.

notes on natural selection

Note that individuals do not evolve; populations evolve over time Natural selection does not create new traits, but edits or selects for traits already present in the population Natural selection can only increase or decrease heritable traits that vary in a population Environmental conditions determine the pressures of natural selection which traits will be selected for or selected against in any specific population Adaptations vary with different environments

convergent evolution

Occurs when organisms that are not closely related but that live in similar environments in separate locations independently evolve similar traits as a result of having to adapt to similar environments or ecological niches. the evolution of similar, or analogous, features in distantly related groups Analogous traits arise when groups independently adapt to similar environments in similar ways Convergent evolution does not provide information about ancestry

extinction

Occurs when the last member of a species dies and the species ceases to exist

toxins in environment

One reason toxins are harmful is that they become more concentrated in successive trophic levels Biological magnification concentrates toxins at higher trophic levels, where biomass is lower PCBs and many pesticides such as DDT are subject to biological magnification in ecosystems DDT was banned in the United States in 1971 Countries with malaria face a trade-off between using DDT to kill mosquitoes (malarial vectors) and protecting other species

detritivores and decomposers

Organisms that consume nonliving organic matter Detritivores Scavenge waste and dead bodies Millipedes, soil insects, lobster Decomposers Break down nonliving matter into smaller molecules Fungi, bacteria Enhance topsoil and recycle nutrients These play an especially important role in cycling nutrients back into soil for plants to use

specialist

Organisms that have a specific niche Live in only one type of habitat Eat only one or a few types of food Tolerate only a narrow range of environmental conditions

genetically modified organisms

Organisms that have been genetically engineered using recombinant dna transgenic organisms contain recombinant DNA, meaning it has been produced from multiple organisms. Genetically modified organisms hold promise to enhance nutrition and agricultural efficiency risks are not well understood, leading to anxiety and protest by consumer advocates, small farmers, environmentalists, and critics of big business

generalist

Organisms with a broad niche Can live in many different places Eat a variety of foods Tolerate a wide range of environmental conditions

many species await discovery

Our knowledge of species numbers is incomplete Small organisms are easily overlooked Many organisms are difficult to identify Some areas of Earth remain little explored ~1.8 million species have been described Most widely accepted estimate of the number of species? 14 million Estimate range from 3-100 million species on Earth

overharvesting

Overharvesting - human harvesting of wild plants or animals at rates exceeding the ability of populations of those species to rebound Large organisms with low reproductive rates are especially vulnerable to overharvesting elephant populations declined because of harvesting for ivory African elephants: Tusks for ivory African rhinoceroses: horns Asian tigers: body parts African gorillas and primates: "Bush meat" Whales Sharks: fins for soup Governments pass laws, sign treaties, and strengthen anti-poaching efforts

pathogens

Parasites that cause disease in hosts Protists, bacteria, and viruses Scabies Elephantiasis Toxoplasmosis Giardiasis Dengue fever Malaria (protist) Tuberculosis (bacteria) Hepatitis (virus) Etc. Parasites that cause disease are called pathogens. Pathogens can be protists (malaria), bacteria (tuberculosis), or viruses (hepatitis).

endoparasites

Parasites that live within the body of their host live within the host Tapeworms Heartworms Hookworm Pinworms

weathering pt 2

Parent material is broken down into smaller particles by weathering. Physical weathering results from wind, rain, freezing, and thawing. Chemical weathering occurs as water or gases chemically alter rock. Biological weathering involves living things, such as lichens producing acid or tree roots rubbing against rock. Further biological activity deposits organic matter in the form of decomposed organisms or waste. Partially decomposed organic matter is called humus and is very productive for plant life. Weathering and the accumulation of organic matter are influenced by: Climate: Warm, moist climates accelerate most weathering processes. Organisms: Plants and decomposers add organic material. Topography: Hills and valleys affect exposure to sun, wind, and water, and influence soil movement. Parent material: Its composition influences soil formation. Time: Soil formation can take centuries, decades, or millennia. Soil is renewable, but at a very slow rate.

weathering

Parent material is broken down into smaller particles by weathering. Physical weathering results from wind, rain, freezing, and thawing. Chemical weathering occurs as water or gases chemically alter rock. Biological weathering involves living things, such as lichens producing acid or tree roots rubbing against rock. Weathering and the accumulation of organic matter are influenced by: Climate: Warm, moist climates accelerate most weathering processes. Organisms: Plants and decomposers add organic material. Topography: Hills and valleys affect exposure to sun, wind, and water, and influence soil movement. Parent material: Its composition influences soil formation. Time: Soil formation can take centuries, decades, or millennia.

intercropping

Planting alternating bands of different crops Decreases pests and disease Replenishes soil involves planting alternating bands of different crops. Cover crops can be used to reduce wind erosion, and legumes can be used to restore nitrogen.

contour farming

Plowing perpendicularly across a hill Furrows slow runoff and capture soil Water has the most erosive power when it moves downhill, so farmers may use contour plowing and plow sideways across a hillside. Each furrow runs perpendicular to the hill's slope, serving as a small dam that stops water flow.

pollution

Pollution harms organisms in many ways Air pollution degrades forest ecosystems Pollution harms organisms in many ways Noise and light interfere with behavior and habitat use of animals Pollution harms organisms in many ways Water pollution impairs fish and amphibians Agricultural runoff (fertilizers, pesticides, sediments) harms terrestrial and aquatic species Pharmaceutical drugs enter freshwater ecosystems through human sewage and agricultural runoff Estrogen used in birth control pills can cause feminization of males in some species of fish Pollution harms organisms in many ways Toxins, garbage, oil, and chemicals impact organisms

subspecies

Populations of species that occur in different areas and differ slightly from each other

greater prarie chicken and the extinction vortex

Populations of the greater prairie chicken were fragmented by agriculture and later found to exhibit decreased fertility To test the extinction vortex hypothesis, scientists imported genetic variation by transplanting birds from larger populations The declining population rebounded, confirming that low genetic variation had been causing an extinction vortex

genetic diversity qs

Populations with higher genetic diversity Survive better and can better cope with environmental change or disease Populations with low genetic diversity Are vulnerable to environmental change or disease

changing face of agriculture

Practice of raising crops and livestock for human use and consumption Cropland - Land used to raise crops for human use Rangeland / Pasture - Land used for grazing livestock Land devoted to agriculture now covers 38% of Earth's land for human use and consumption. Most of our food and fiber is obtained from cropland, land used to raise crops for human use. Rangeland, or pasture, is land used for grazing livestock. Growing crops and raising animals require inputs of resources - soil, sunlight, water, nutrients, and pollinators. Today, more than 1 out of every 3 acres of land on Earth is used to produce food and fiber. Agriculture provides our most basic daily needs - from the cotton in our clothes to the food on our plates. Agriculture is also responsible for some of our biggest impacts on the environment, making the development of sustainable practices essential. Agriculture provides our most basic daily needs—from the cotton in our clothes to the food on our plates. Agriculture is also responsible for some of our biggest impacts on the environment, making the development of sustainable practices essential.

examples of restoration efforts

Prairie restoration Replanting native vegetation, controlling invasive species, using controlled fire to mimic natural fires The world's largest project: Florida Everglades Flood control and irrigation removed its water Populations of wading birds dropped 90-95% It will take 30 years and billions of dollars to restore natural water flow In Florida, dams, canals, and levees are being undone to restore the natural water flow Prairie restoration Replanting native vegetation, controlling invasive species, using controlled fire to mimic natural fires The world's largest project: Florida Everglades Flood control and irrigation removed its water Populations of wading birds dropped 90-95% It will take 30 years and billions of dollars to restore natural water flow In Florida, dams, canals, and levees are being undone to restore the natural water flow Prairie restoration Replanting native vegetation, controlling invasive species, using controlled fire to mimic natural fires The world's largest project: Florida Everglades Flood control and irrigation removed its water Populations of wading birds dropped 90-95% It will take 30 years and billions of dollars to restore natural water flow In Florida, dams, canals, and levees are being undone to restore the natural water flow How good are we at restoration? Compare undisturbed biodiversity and ecological complexity to restoration efforts The alteration of ecosystems creates "winners" and "losers" among the world's animals and plants. Humans have a tendency to change ecosystems so that they are more similar to each other, more open in structure, and more polluted. This favors generalists, which can adapt to the changing conditions, and harms specialists, which rely on mature, stable ecosystems.

trophic cascade

Predators at high trophic levels indirectly promote populations at low trophic levels by keeping species at intermediate trophic levels in check If top predators are lost, primary consumers will overconsume producers and alter the entire ecosystem. If top predators are lost, primary consumers will overconsume producers and alter the entire ecosystem. This is called a trophic cascade. This is one example of an ecological disturbance. Biodiversity increases the resilience of an ecosystem—its ability to withstand disturbance, recover from stress, or adapt to change. If a keystone species like a top predator is lost, consequences will cascade down the entire food chain. If an ecosystem engineer is lost, the entire structure of an ecosystem can change. The removal of elephants from some of Africa's savannas has caused scrubby vegetation to overgrow, turning them into scrub forests.

Parks and protected areas conserve biodiversity at the ecosystem level

Preserving land in parks and protected areas conserves habitats, communities, ecosystems, and landscapes 13% of the world's area is in parks, wilderness, reserves, etc. But not all of these areas are managed for biodiversity They are used for recreation, water protection, etc. They are also illegally logged, are poached, or have their resources extracted Some are large enough to preserve whole systems Linking protected areas by corridors allows populations to intermix

producers the 1st trophic level

Primary Producers, or autotrophs ("self-feeders") Organisms that use photosynthesis or chemosynthesis to make their own sugars. Green plants Cyanobacteria Algae

consumers consume producers

Primary consumers(second trophic level) Organisms that consume producers Herbivores: deer, grasshoppers Secondary consumers (third trophic level) Organisms that prey on primary consumers wolves, rodents, birds Tertiary consumers (fourth trophic level) Organisms that prey on secondary consumers Predators: hawks, owls

predation

Process by which individuals of one species (predators) capture, kill, and consume individuals of another species (prey) is the process by which individuals of one species (the predators) capture, kill, and consume individuals of another (the prey). Asian carp were introduced to prey on algae and snails. Predators that are better at capturing prey will live longer and reproduce more. Natural selection will favor adaptations that enhance hunting. Prey have the risk of death as a selective pressure, causing the evolution of many types of defenses. Figure 4.4 Natural selection to avoid predation has resulted in fabulous adaptations.

convergent evolution

Process by which unrelated organisms independently evolve similarities when adapting to similar environments is the process whereby organisms not closely related, independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.

overnutrition

Receiving too many calories each day Overindulgence or excessive intake of specific nutrients Excess weight leads to heart disease, diabetes, stroke, some forms of cancer, and other health issues. lowers life expectancy, lowers productivity, etc. Worldwide, 1.5 billion adults are overweight At least 500 million of those are obese

organismal ecology

Relationships between individuals and their environment

taxonomists

Scientists who name and classify organisms according to their genetic makeup and physical appearances Have developed a hierarchical system to categorize them

ecologists

Study relationships/interactions among organisms and their environment at many levels

case study: serengeti

Serengeti National Park Located in East Africa One of the last places on the planet where an ecosystem remains intact and functional 1.2 million wildebeest migrate year Part of an epic migration that has occurred for millennia Maasai Mara National Reserve Located in Kenya Connected to Serengeti Migratory animals move between both A proposed highway would slice through the middle of the wildebeest migration path Conservationists as well as most Kenyans are opposed to the highway because it would Block migration Devastate tourism Provide access to poaching Promote invasion of exotic plant species Encourage human development As of 2014, the project is still being discussed, and the new Tanzanian government continues to push for the construction of the road

temperate rainforest

Significant amounts of precipitation fall during all seasons as rain or snow Coniferous trees Cedar, spruce, hemlock, fir Moisture-loving animals Banana slug Erosion and landslides affect the fertile soil Most old-growth is gone as a result of logging Temperate rainforests are rich in rainfall but still found in mid-latitudes. Mostly contain coniferous trees. Soils are fertile, but susceptible to erosion if the forests are cleared

lakes

Size varies from small ponds to very large lakes Oxygen rich or poor Nutrient rich or poor Deep or shallow oligotrophic eutrophic

dust bowl response by US

Soil Conservation Service (SCS) Started in 1935 by Congress Works with farmers to develop conservation plans for farms Now named the Natural Resources Conservation Service (NRCS) Employs trained experts called extension agents to assist farmers Other countries started their own conservation agencies In response, the U.S. government passed the Soil Conservation Act of 1935, which established an agency that worked with farmers to combat erosion. The agency today is known as the Natural Resources Conservation Service and employs trained experts called extension agents to assist farmers.

conserving agricultural resources

Soil degradation - deterioration in quality and productivity of soil Causes include: Soil erosion Nutrient depletion Water scarcity Salinization Waterlogging Chemical pollution Changes in soil structure and pH Loss of organic matter from soil Soil compaction

soil forms slowly

Soil formation begins during primary succession, as water, air, and living organisms break down parent material in the lithospher

biodiversity is unevenly distributed on earth

Species diversity is higher near the equator Some groups have more species than others Insects predominate over all other life-forms Beetles outnumber all non-insect animals and plants

allopatric speciation

Species form as a result of physical separation of populations The main mode of speciation Populations can be separated by glaciers, rivers, mountains Each population, with its own set of mutations, diverges

can extinct species be resurrected

Species recovery may be possible through cloning technology if frozen tissue is available Current research is underway to determine if ancient extinct species frozen in Arctic ice can be successfully cloned In cloning, DNA from an endangered species is inserted into an egg without a nucleus The egg is inserted into a closely related species Several mammal species have been cloned But these efforts are not enough to recreate lost biodiversity Without ample habitat and protection in the wild, having cloned animals in a zoo does little good Resurrection of extinct species raises ethical questions ....should we??? ex: The last natural Pyrenean ibex, a female named Celia, was found dead on January 6, 2000. Although her cause of death is known (she was killed by a fallen tree), the reason for the extinction of the subspecies as a whole is a mystery. Some hypotheses include the inability to compete with other species for food, infections and diseases, and poaching. The Pyrenean ibex became the first taxon ever to become "unextinct", for a period of seven minutes in January 2009, when a cloned female ibex was born alive and survived a short time, before dying from lung defects.[8][9]

ecosystem ecology

Studies living and nonliving components of systems to reveal patterns

ecology

Study of interactions among organisms and their environment Ecology and evolution are tightly intertwined

conservation geneticists

Study the effects of loss of genetic variation (e.g., inbreeding depression) Minimum viable population size How small a population can become before it runs into problems Small populations are most vulnerable to extinction and need special attention Scientists study species dispersal and gene flow To determine how likely that a population will persist when faced with habitat change or other threats

fertilizers boost yields but can be overapplied

Substances containing essential nutrients (nitrogen, phosphorus, potassium, etc.) to enhance crop production inorganic organic Inorganic fertilizers are mined or synthetically manufactured. Organic fertilizers are made of the remains or wastes from organisms, including manure, crop residue, charcoal, fresh vegetation, and compost. Compost is a mixture produced when decomposers break down organic matter in a controlled environment. Boosted global production in the late 1900s But can severely pollute Leaching and runoff of fertilizers causes: Groundwater contamination Dead zones in water systems (eutrophication) Air pollution from evaporated nitrates

sustainable agriculture

Suitable farmland is disappearing We must improve the efficiency of production We need to raise animals and crops that pollute less, require less fuels, and have less impact on natural systems Agriculture that maintains healthy soil, clean water, pollinators, genetic diversity, and other vital resources Tries to mimic how natural ecosystems function maintains healthy soil, clean water, pollinators, and other vital resources. The overall approach is to mimic the way natural ecosystems function. Achieving sustainable agriculture requires an understanding of the soil, water, nutrients, and pollinators that underpin agriculture. Farming methods that preserve long-term productivity of land and minimize pollution, typically by rotating soil- restoring crops with cash crops and reducing in-puts of fertilizer and pesticides.

growth of organic agriculture

Sustainable agriculture keeps high crop yields, minimizes resource use, and decreases environmental impacts Organic agriculture Food-growing practices that do not include synthetic pesticides, fertilizers, hormones, or antibiotics Organic Food Production Act (1990) established national standards for organic products The USDA issued criteria by which food could be labeled organic California, Washington, Texas passed stricter guidelines for labeling One approach to sustainable agriculture is organic agriculture, which involves food-growing practices that do not include synthetic pesticides, fertilizers, hormones, or antibiotics. The Organic Food Production Act of 1990 established national standards by which foods can be labeled as organic.

Sustainable agriculture provides a roadmap for the future

Sustainable agriculture must meet the triple bottom line of social, economic, and environmental dimensions: Provide food security Be profitable to famers and ranchers Conserve resources for future agriculture Sustainable agriculture mimics natural ecosystems They operate in cycles and are internally stabilized by negative feedback loops Agricultural systems can be integrated with the surrounding ecosystems Reducing environmental impacts from food production Making agriculture sustainable is crucial for all of us

sustainable fertilizer use involves monitoring and targeting nutrients

Sustainable approaches delivers nutrients directly to plant roots and avoids over application Add fertilizers to drip irrigation water No-till or low-till systems inject fertilizers with seeds Strips of vegetation along field edges and streams capture nutrient runoff precision agriculture Organic fertilizers add nutrients and organic matter Improving soil structure, nutrient and water retention Preferred approach is to integrate inorganic and organic fertilizer systems Farmers who use drip irrigation can add fertilizer directly to the water, thereby releasing it only at the plant roots. Organic fertilizer use is embraced, because it provides additional benefits, such as improving soil structure, nutrient retention, and water-retaining capacity.

pesticides

Synthetic chemicals that kill pests Insecticides kill insects Herbicides kill plants Fungicides kill fungi can cause health problems for humans and kill non-target organisms such as pollinators and natural predators of pests Pesticides include synthetic chemicals that kill insects (insecticides), plants (herbicides), and fungi (fungicides). Nearly 400 million kg of ingredients from pesticides are applied in the United States each year. Pesticides also kill nontarget organisms, including predators and parasites of pests and pollinators.

bottleneck effect

The Bottleneck Effect occurs when a natural disaster forces a certain species into near extinction. The few individual species that are left are forced to mate with each other, sometimes inbreeding, thus causing almost no variation in the gene pool. This can cause a problem if a disease starts to infect and kill some of the individual species. An example of this effect would be the cheetahs. Cheetahs are now on the endangered list because their small gene pool, which is 97% identical, is inhibiting successful reproduction and adaptation.

case study: kennesaw state university

The Commons at Kennesaw Sate University Leaders with "closed-loop" culinary sustainability programs Committed to sustainability runs three farms, producing much of the produce consumed by the students Uneaten food waste is composted and returned to the soil as fertilizer Minimized energy use Minimized water consumption Minimized waste generation Provides biodiesel for vehicles Campus dining services, such as at Kennesaw State University, are becoming leaders with "closed-loop" culinary sustainability programs. KSU runs three farms, producing much of the produce consumed by the students. Uneaten food waste is composted and returned to the soil as fertilizer. The KSU dining commons was designed with sustainability in mind. Floor-to-ceiling windows provide daytime lighting. Food is prepared to order or in small batches, minimizing waste. Dishwashing systems have high water and energy efficiency. Water bottle refilling stations reduce plastic waste. Recycling and composting programs divert over 44,000 pounds of waste per month from the landfill. Biodiesel is generated from used cooking oil. The farms are also designed to maximize sustainability. Chemical pesticide and synthetic fertilizer use is minimized. Hydroponic stations supplied by rainwater produce herbs, lettuce, and shiitake mushrooms. Off-campus food sources are kept local whenever possible. This and other university operations help to serve as models for nationwide agriculture reforms that could change how food is produced and delivered.

weighing the issue

The Footprints of Our Diets The pyramid pattern of energy and biomass illustrates why eating at lower trophic levels decreases your ecological footprint What proportion of your diet would you estimate consists of meat, milk, eggs, or other animal products? Would you choose to decrease this proportion in order to reduce your ecological footprint? Describe other ways in which you could reduce your footprint through your food choices.

do you want food labeled

The USDA issues labels to certify that products claiming to be organic have met the government's organic standards. Critics of genetically modified food want GM products to be labeled as well. Do you want your food labeled to indicate whether it is organic or genetically modified? Would you choose among foods based on such labeling? How might your food choices and purchasing decisions have environmental impacts (good or bad)?

biotechnology

The application of biological science to create products derived from organisms It has helped to develop medicines, clean up pollution, aid cancer research, dissolve blood clots, make better food ex: production of human insulin from non human resources production of hormones like interferons cytokinins steroids and hgh gene therapy for prevention and control of diseases like hemophilia and cystic fibrosis development of vaccines and antibodies for rabies hiv etc

successful reproduction

The best adapted to their environment are likely to have many offspring that survive.

salinization

The buildup of salts in surface soil layers Salinization inhibits production of 20% of irrigated cropland, costing over $11 billion/year in lost productivity buildup of salts in surface soil layers as a result of irrigation.

undernutrition

The condition in which not enough calories are ingested to maintain health receiving fewer calories than the minimum dietary requirement. Every 5 seconds a child starves to death By 2050 we will have to feed 9 billion people 800 million people suffer from undernutrition, receiving fewer calories than the minimum dietary requirement. Most people who are undernourished live in developing countries, although 49 million people are classified as "food insecure."

fossil record

The cumulative body of fossils worldwide The fossil record provides evidence of the extinction of species the origin of new groups changes within groups over time Numbers of species speciation extinction

extirpation local extinction

The disappearance of a population from a given area, but not the entire species globally Over time, it can lead to extinction

extinction

The disappearance of a species from Earth Most species that once lived are now gone Species last 1-10 million years Biological diversity is now being lost at an astounding rate This loss of species is irreversible Rapid environmental changes increase extinction Natural selection can't keep up, so species can't adapt Many factors cause extinction Climate change, changing sea levels, severe weather Arrival of new species Small populations Specialized species

foods can be genetically modified

The first genetically modified animal to become approved for human consumption is a salmon that can grow faster and reach larger sizes than wild salmon. biotechnology

The race to feed the world

The industrialization of agriculture has boosted worldwide production of food and fiber immensely, but has also brought increased pollution and resource depletion. Organic farming decreases efficiency, but also has far fewer environmental impacts. Food production currently exceeds population growth But not everyone has enough to eat 800 million people suffer from undernutrition The industrialization of agriculture has boosted worldwide production of food and fiber immensely, but has also brought increased pollution and resource depletion. Organic farming decreases efficiency, but also has far fewer environmental impacts. Despite improved food production Food security

streams and rivers

The most prominent physical characteristic is current

a soil profile consists of layers known as horizons

The movement and sorting of soil particles creates distinct layers called soil horizons. The entire cross-section of soil is the soil profile. Generally, the degree of weathering and concentration of organic matter decrease as one moves downward in a soil profile. leaching The soils of the Amazon rainforest are much less agriculturally productive than those in Iowa or Kansas. The higher amount of precipitation quickly leaches nutrients out of the topsoil and E horizon.

ecosystem diversity

The number and variety of ecosystems Some biologists also refer to community or habitat diversity It may include habitats, communities, or ecosystems at the landscape level Sizes, shapes, and connections among patches matter Areas with a variety of vegetation hold more biodiversity than areas the same size with one plant type Example: Serengeti's open plains are vast, but the region has a diversity of habitats Savanna, grasslands, hilly woodlands, seasonal wetlands, and rocky outcroppings

species diversity

The number or variety of species in a particular region Richness: the number of species Species Richness (numbers of species) speciation extinction Speciation generates new species Extinction reduces species richness Evenness (relative abundance): the extent to which species differ in number of individuals

ecological restoration

The on-the-ground efforts to restore an area Difficult, time-consuming, and expensive It is best to protect natural systems from degradation in the first place

succession

The predictable series of changes in a community after a severe disturbance eliminates all or most of the species in a community Severe disturbances may eliminate all or most of the species in a community, initiating a series of changes called succession. Succession begins with the colonization of pioneer species. Pioneer species, such as grasses and forbs, spread over long distances easily and are adapted for growing quickly. Primary succession occurs when a disturbance removes all plant or soil life. Lichens secrete acids that break down rock, beginning the process of soil formation.

speciation

The process of generating new species Natural selection cause an ancestral species to give rise to two or more descendent species

artificial selection

The process of selection conducted under human direction

natural selection

The process where inherited characteristics that enhance survival and reproduction are passed on more frequently to future generations than those that do not A primary mechanism of evolution and biological diversity

organic fertilizers

The remains or wastes from organisms Manure, crop residues, fresh vegetation (green manure), charcoal, and compost

restoration ecology

The science of restoring an altered area to an earlier (pre-settlement/pre-disturbance/pre-industrialized) condition Tries to restore the system's functionality (Example: filtering of water by a wetland)

small population approach

The small-population approach studies processes that can make small populations become extinct inbreeding and genetic drift, draw a small population down an extinction vortex

amazon rainforest

The soils of the Amazon rainforest are much less agriculturally productive than those in Iowa or Kansas. The higher amount of precipitation quickly leaches nutrients out of the topsoil and E horizon. Tropical farmers may practice swidden agriculture, where they cultivate a plot for a few years and then move on to another. If enough time is allowed, the soil and forest can recover. Plots are often burned first, a practice called slash-and-burn agriculture.

type of biome depends on

The type of biome depends on: Temperature, precipitation, sunlight, soil conditions, air and ocean circulation Climate diagrams (climatographs) Depict information on temperature and precipitation Temperature and precipitation exert the greatest influence on which biome is found in a given area. Temperature and precipitation are the main factors determining where each biome occurs. Climate diagrams, also called climatographs, depict seasonal changes in temperature and precipitation and help to tell the story of a biome. Deciduous forests, for example, are found at mid-latitudes and have relatively even precipitation throughout the year. Winters are frozen, causing the trees to drop their leaves

biodiversity

The variety of life across all levels of biological organization Genetic diversity - genetic variation within a population and between populations Species diversity - variety and abundance of species in a community, an ecosystem or throughout the biosphere Ecosystem diversity - variety of ecosystems in the biosphere

biodiversity (biological diversity)

The variety of life across all levels of biological organization, including the diversity of species, their genes, their populations, and their communities. Includes Genetic diversity - Molecules (Genes) Species diversity Community diversity Ecosystem diversity

coevolution

These populations adapt and counter-adapt to each other through a process called coevolution. The duel of escalating adaptations between predaror and prey, parasite and host, herbivore and plant is known as an evolutionary arms race. Predator and prey Herbivore and plant Parasite and host Mutualists become locked in a duel of escalating adaptations (evolutionary arms race) Each evolves new responses to the other

oceanic pelagic zone

This biome covers approximately 70% of Earth's surface Phytoplankton and zooplankton are the dominant organisms Overfishing has depleted fish stocks Humans have polluted oceans with dumping of waste

inference #2

This unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations 1. population with varied inherited traits 2. elimination of individuals with certain traits 3. reproduction of survivors 4. increasing frequency of traits that enhance survival

overgrazing

Too many animals eat too much of the plant biomass without adequate regeneration and impede plant regrowth Soil is exposed, degraded, eroded and compacted makes it harder for plants to grow (positive feedback loop) Non-native plants invade, which are less palatable to livestock and outcompete native vegetation Humans keep over 3 billion cattle, sheep, and goats 70% of the world's rangeland is degraded, costing $23 billion/year in lost productivity If livestock populations do not exceed the carrying capacity, rangelands can still be functional ecosystems. Without adequate regeneration of plant biomass, the result is overgrazing. Overgrazing exposes soil and makes it vulnerable to erosion. In a positive feedback loop, soil erosion makes it more difficult for native plants to grow, perpetuating the problem

eradication

Total elimination of a population Often difficult to accomplish

ecotourism

Tourists visit protected areas Hawaii's residents are benefiting from their conservation efforts.

savanna

Tropical grassland interspersed with trees Precipitation occurs only during the rainy season The dominant plant species are fire-adapted and tolerant of seasonal drought Grasses and forbs make up most of the ground cover Zebras, gazelles, giraffes, lions, hyenas Savannas are tropical grassland interspersed with acacias or other trees. Found in dry tropical areas, including parts of Africa, Australia, and India. Distinct wet and dry seasons. kenya

international treaties promote conservation:

U.N. Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) (1973) Protects endangered species by banning international transport of their body parts Convention on Biological Diversity (1992) Seeks to conserve biodiversity Seeks to use biodiversity in a sustainable manner Seeks to ensure the fair distribution of biodiversity's benefits Goal - "to achieve, by 2010, a significant reduction of the current rate of biodiversity loss" Goal was NOT met

pollinators are beneficial bugs worth preserving

U.S. bees provide $15 billion/year in pollination services essential to over 100 crops that make up 1/3 of the U.S. diet Many beekeepers were driven to financial ruin when parasitic wasps spread and decimated their bee hives Colony collapse disorder One-third of all U.S. honeybees have died Causes are unknown but may involve: Insecticides New parasites A combination of stresses that weaken bees' immune systems and destroy social communication Today, many pollinating insects are dwindling in number due to pesticide use and habitat loss. Colony collapse disorder is a phenomenon where a majority of worker bees in a hive disappear, endangering the queen and developing larvae. Restoring bee populations will require establishing more wildflowers and flowering shrubs near farm fields and highways and decreasing the use of chemical insecticides.

estuaries

a transition area between river and sea Salinity varies with the rise and fall of the tides

biological control - biocontrol

Uses a pest's predators, parasites or diseases to control the pest Parasitoid wasps are natural enemies of many caterpillars. Introduction of cactus moth from Argentina to Australia Risks of biocontrol Organisms can't easily be controlled Organisms can harm non-target organisms Example: cactus moths introduced to Caribbean islands spread to Florida and are eating native cacti in southeastern U.S. Biocontrol must be carefully planned and regulated The most obvious alternative to chemical pesticides is biological control or biocontrol, where natural predators or parasites are introduced to eliminate the pest. Parasitoid wasps, for example, are natural enemies of many caterpillars. A modern example of biological control is the use of the Bacillus thuringiensis (Bt) soil bacterium, which produces a protein that kills many caterpillars and some fly and beetle larvae. Bt spores can be sprayed directly on plants. The gene responsible for producing the protein has been genetically engineered into crop plants, allowing them to produce the poison. Biocontrol organisms have, in some cases, become invasive and harmed nontarget organisms. The cactus moth, a natural predator employed in Australia to fight prickly pear cactus, was also used in Caribbean countries, but has spread into the United States and is now consuming native cacti.

industrial agriculture

Uses large-scale mechanization and fossil fuel consumption to boost yields Higher rates of irrigation, synthetic fertilizers, and chemical pesticides Plant monocultures - a single, genetically similar crop More efficient but reduces diversity; is disease prone Narrows the human diet introduced large-scale mechanization and fossil fuel consumption into agriculture. Higher rates of irrigation, synthetic fertilizers, and chemical pesticides Greater prevalence of monocultures, where farmers grow vast areas of single crops in orderly rows

low input agriculture

Uses less amounts of fossil fuels, water, pesticides, fertilizers, growth hormones, and antibiotics than industrial agriculture an approach that uses less amounts of fossil fuels, water, pesticides, fertilizers, growth hormones, and antibiotics than are used in industrial agriculture.

inherited variation

Variation in a characteristic that is a result of genetic inheritance from the parents

waterlogging

Water drowns plant roots in over irrigated soils occurs when irrigation oversaturates the soil to the point where water drowns plant roots, depriving them of gases.

6th mass extinction event

We are setting the sixth mass extinction in motion Red List by the Union for Conservation of Nature Species facing high risks of extinction 2014 Red List reported Mammal species (22%) Bird species (13%), Amphibian species (31%) Fish species (20%) In the last 500 years, 236 animal and 30 plant species have gone extinct in the United States Actual numbers are undoubtedly higher Humans have driven hundreds of species to extinction in the past few centuries North American birds that are now extinct: Carolina parakeet Great auk Labrador duck Passenger pigeon Bachman's warbler Eskimo curlew Possibly the ivory-billed woodpecker Species that teeter on the brink of extinction: Whooping crane, Kirtland's warbler, California condor

single species conservation

What would you say are some advantages of focusing on conserving single species, versus trying to conserve broader communities, ecosystems, or landscapes? What might be some of the disadvantages? Which do you think is the better approach, or should we use both, and why?

competition

When species compete for a resource in short supply Multiple organisms seek the same limited resource Food, water, space, shelter, mates, sunlight, etc. Negative - negative interaction each participant negatively affects the other by taking resources Becomes more intense when populations are more dense Organisms that seek the same resource have a relationship called competition. Intraspecific Interspecific Competition becomes more intense when populations are more dense. In competitive interactions, each participant negatively affects the other by taking resources.

how productive is organic farming

World's longest-running field experiments on organic farming are in Switzerland and Pennsylvania After more than 21 years of studies, Dr. Paul Mäder's team concluded that organic plots were highly efficient and represent "a realistic alternative to conventional farming" Mäder's team found that soil in organic plots had Better structure Better supply of some nutrients Much more microbial activity Much more invertebrate biodiversity Organic crops Equaled conventional crops in yield Produced more profit Required less energy input Released fewer greenhouse gas emissions

aquaculture

Worldwide fish populations are plummeting due to Increased demand and technology (fish farms) - raising aquatic organisms in a controlled environment Open-water pens or land-based ponds or holding tanks The fastest-growing type offood production

tropical rainforest

Year-round rain and warm temperatures Dark and damp Lush vegetation Diverse species But in low densities Very poor, acidic soils Nutrients are in the plants Tropical rainforests have dark, damp interiors, lush vegetation, and highly diverse communities. High numbers of tree species intermixed at low densities. Acidic soils that are low in organic matter.

wetlands

a habitat that is inundated by water at least some of the time and that supports plants adapted to water-saturated soil

symbiosis

a relationship where two or more species live in direct and intimate contact with one another Parasitism Commensalism Mutualism

malnutrition

a shortage of specific nutrients, such as lipids, proteins, vitamins, or minerals medical condition caused by improper or insufficient diet

precision agriculture

agriculture involves monitoring soil nutrient levels and only applying specific types of fertilizer when nutrient levels are low involves monitoring soil nutrient levels and only applying specific types of fertilizer when needed.