Biology 2-OSU-Unit 5

Ecology

the study of the interaction of organisms with their environment, on the individual, population, community, or ecosystem level

Population ecology

the study of how and why the number of individuals in a population changes over time

Darwin’s important population thinking

recognizing variation among individuals in a population is key to understanding how populations change over time in response to their habitats

Exponential model of population growth

describes a population in an idealized and unlimited environment, helps us understand the capacity a species has to grow and the conditions that might facilitate this growth

Change in population growth model

births-death+immigration-emigrants

per capita rate of increase, r

the difference between the birth and death rates

N

number of individuals in a population

r_max

when birthrates are as high as possible and death rates are as low as possible

Exponential growth is common in what kinds of populations

when a new habitat is being colonized, when recovering after a disaster

Logistic growth

when population density gets very high r declines, density dependent growth, depends on K

Carrying capacity, K

the maximum number of individuals in a population that can be supported in a particular habitat over a sustained period of time

Density-dependent factors that limit population size include…

competition for resources, disease and parasitism, predation, toxic waste, and social behavior

Population crash

occurs when a population overshoots their carrying capacity which leads to an intense population drop

Predator-prey relationships

as the number of prey increase so does predator, when prey decreases so does predator

Population pyramid/ age pyramid

researchers use stacks of horizontal bars to plot the number of males and females in each age interval

Communities

an assemblage of populations of various species living close enough for potential interaction

Interspecific interactions

relationships between species in a community, ex: competition, predation, symbiosis, facilitation

Interspecific interaction

a negative negative interaction, when species compete for a resource in short supply, can lead to the elimination of a species

Ecological niche

the total of a species’ use of biotic and abiotic resources

Ecologically similar species can coexist in a community if there are one or more significant _________ in their __________

differences; niches

Resource partitioning

differentiation of ecological niches, enabling similar species to coexist in a community

Fundamental niche

the niche potentially occupied by that species if no other species were present

Realized niche

the niche actually occupied by a species when others are present

Predation

a positive negative interaction, one species or predator kills and eats the other or the prey

Predation exerts strong __________ ________________ on prey

selective pressure

Cryptic coloration (camouflage)

an adaptation that makes prey difficult to spot

Aposematic coloration

used by some animals with effective chemical defense, bright warning coloration

Mimicry

a prey species gains protection by mimicking the appearance of another species

Symbiosis

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

Parastism

a type of community interaction; one organism or the parasite derives nourishment from another organism or the host, the host is harmed

Brood parasitism

an animal lays its young in another animals nest, the parent raises the animal as its own, many time the young kill the true children of the parent

Mutualism

community interactions; an interaction that benefits both species

Commensalism

a community interactions; one species is benefitted and the other is neither harmed nor helped

Facilitation

(+/+ or 0/+), a community interaction, one species has positive effects on another species without direct and intimate contact; ex: one plant making soil more nutrient dense

Succession

a gradual change is species composition over time

Primary succession

a gradual change in species composition over time starting with no soil present

Secondary succession

a gradual change in species composition over time after a community has been damaged but soil remains

Early arriving species in succession

may facilitate the appearance of later species, may inhibit the establishment of later species, may tolerate later species with no impact

Ecosystem

consists of the multiple communities of organisms that live in an area along with abiotic components such as the soil, climate, water, and atmosphere

The biotic and abiotic components of an ecosystem are linked by the flows of _________ and ___________

energy; nutrients

Gross primary productivity (GPP)

the total amount of chemical energy produced in a given area and time period

Primary producers

uses GPP energy to stay alive through cellular respiration, uses remaining GPP for growth and reproduction

Net primary productivity (NPP)

energy from GPP put toward growth and reproduction in primary producers

Energy is ____________ when one organism eats another

transferred

Nutrients essential to life include….

carbon, nitrogen, phosphorus, sulfur, calcium

Biogeochemical cycle

the path that an element takes as it moves from abiotic systems through organisms and back again

the Global Nitrogen Cycle

nitrogen is added to ecosystems in a useable form only when it is reduced or fixed

Lightning driven reactions and enzyme-catalyzed reactions

cause nitrogen fixation, converting N2 into NH4 and NO3 which is useable

Nitrogen pollution

from the burning of fossil fuels; causes acid rain. climate change, and depletion of the ozone layer

Eutrophication

overfertilization; can cause algal blooms in aquatic ecosystems which cause oxygen free “dead zones”

The Carbon Cycle

the movement of carbon among terrestrial ecosystems, the oceans, and the atmosphere

Photosynthetic organisms convert CO2 to organic molecules used by _____________

heterotrophs

Cellular respiration

releases carbon from living organisms into the atmosphere in the form of carbon dioxid

Carbon sinks

carbon reservoirs; includes soils, oceans, plant and animal biomass, the atmosphere, and fossil fuels

Burning fossil fuels moves carbon from an ________ geological reservoir, in the form of petroleum or coal, to an __________ reservoir—the atmosphere

inactive; active

Agriculture and deforestation and the carbon cycle

have added large amounts of carbon dioxide to the atmosphere

The Anthropocene

a proposed epoch in the geological time scale; the biological, chemical, and geological consequences of humans on the earth; have removed species, changed landscapes, and added nutrients to ecosystems

Global warming

the increase in the average temperature of the planet

Global climate change

the sum of all the changes in local temperature and precipitation patterns that result from global warming

Weather

the short-term, highly variable atmospheric conditions such as temperature, moisture, sunlight, and wind at a specific place and time

Climate

the long-term average pattern of regional or global weather

Global climate change is caused by

burning fossil fuels adding CO2 to the atmosphere faster than it can be removed, the clearing or forests, the accumulation of CO2 and other greenhouse gases

Greenhouse effect

greenhouse gases accumulate and trap heat, act as an atmospheric blanket, without it Earth would be too cold to support life

Green houses gases

airborne chemicals that capture and hold heat within Earth’s atmosphere; includes CO2, CH4, N2O, and H2O

Temperature is expected to _______ as time goes on

vary

Biodiversity

biological diversity

Genetic diversity

comprises genetic variation within a population and between populations

Species diversity

the variety of species in an ecosystem or throughout the biosphere

Ecosystem diversity

the variety of ecosystems in the biosphere

Human biophilia

allows us to recognize the value of biodiversity for its own sake

Ecosystem services

all the processes through which natural ecosystems and their species help sustain human life; includes air and water purification, detoxification and decomposition of waste, nutrient cycling, moderation of weather extremes, and pollination

Background extinctions

normal extinctions that occur during a given period of time

Mass extinctions

a large proportion of species on earth are lost in a short amount of time

Heat trapping gases have _______ and so has global _______, sea water _________ as temperatures rise and ________ glaciers are adding water to the ________. This all causes a _____ in _____ level

increased; temperature; expands; melting; oceans; rise in sea

____________ and _________ ______ are the single biggest threats to biodiversity

deforestation; habitat loss; both result in a further increase in CO₂ in the atmosphere

The primary cause of forest destruction is….

clearing for agriculture

Ecological footprint

an estimate of the amount of land and water required to sustain one person

Invasive species

large threat to biodiversity; no predators, native species cannot compete with them

Overharvesting

the harvesting of a renewable resource at a rate that is unsustainable

Acid rain

burning fossil fuels adds carbonic acid, sulfuric acid, and nitric acid to rain water; lowers the pH of rain and what it lands on

Ocean acidification

the ocean absorbs a lot of CO₂ emissions; affects marine ecosystems; ocean becomes more acidic; lowers calcium levels which makes skeletons of sea life weaker; can lower sea life ability to smell and ability of sperm to swim

Conservation biology

a branch of ecology that seeks to investigate and reverse the loss of biodiversity

Preventing habitat loss

the simplest way to protect biodiversity

Fragmentation

the splitting of habitats that isolate small populations

Corridors

used to connect habitat patches; like an animal bridge over a road

Sustainable development

to maintain the productivity of Earth’s ecosystem indefinitely; policies and education about the biosphere

Restoration ecology

uses ecological principles to help repair degraded areas; mimics processes of secondary succession

Bioremediation

the use of living organisms to decontaminate polluted ecosystems