Ecosystem Ecology and Adaptations

Ecosystem def

the complex of living organisms, physical environment, and interrelationships

earth's ecosystem

closed in terms of chemicals, open in terms of energy

What forces link the biotic/abiotic components in an ecosystem?

cycling of materials, flow of energy

biogeochemical cycles

how atoms move through ecosystems

Carbon cycle

hydrologic cycle

nitrogen cycle

Greenhouse effect

sunlight heats earth surface, CO2 is reflected back

nitrogen fixation

Process of converting nitrogen gas into ammonia

energy flow

one way - no recycling (open system)

primary productivity

rate at which organic matter is created by producers in an ecosystem - dependent on distance from equator

food web

food chain

productivity

rate at which organisms create new material

protoautotrophs

photosynthetic organisms

consumers

obtain energy and nutrients by eating other organisms

heterotrophs is a synonym for

consumers

detrivores

consumers that eat decaying matter

trophic structure

heirarchy or feeding relationship

what is lost as trophic stage progresses?

heat

landscape

heterogeneous area composed of several ecosystems

patch

area that differs from surroundings

landscape structure

physical configuration of the landscape elements

matrix

background in structure mosaic

ecotones

edge of habitat patches

ecosystem engineers

species that dramatically alter their environment

example of ecosystem engineers

beavers, African elephants

edge species exist where?

ecotones

carbon fixation

The initial incorporation of carbon into organic compounds.

landscape ecology

the study of the relationship between spatial pattern and ecological processes

evolution

changes in heritable characteristics of population over time

microevolution

Change in allele frequencies in a population over generations

macroevolution

long-term accumulation of genetic changes

speciation

genesis of new species

Charles Darwin theory of evolution

descent with modification

Lamark theory of evolution

inheritance of acquired characteristics

fitness

ability to survive and reproduce

fercundity

number of offspring produced

types of adaptations

behavioral and morphological

directional selection

occurs when natural selection favors one of the extreme variations of a trait

stabilizing selection

natural selection that favors average individuals in a population

disruptive selection

natural selection that favors opposite extremes

homogolous structures

structures with different functions that arose from the same structure

vestigal structures

structures with no function that resemble ancestral structures

reproductive strategy

a set of behaviors that have evolved to maximize reproductive success

parental investment

the time and energy parents expend for their offspring's benefit

biparental care

both parents provide care for offspring

sexual selection

Natural selection that acts on heritable traits which affect reproduction but may negatively affect survival

sexual dimorphism

Differences between the sexes in morphology

intrasexual selection

competition among individuals of one sex

intersexual selection

individuals of one sex are choosy in selecting their mates from the other sex

reciprocal altrusim

partnerships are formed that will help at one time and expect repayment

evidence for theory of evolution

Fossilization, Embryonic development, Vestigial structures, Homologous structures