Exam 2 Notes - BIO 181

Ecology

the study of relationships between organisms and the environment

Organismal

the study of an organism’s relationship with its environment (biotic and abiotic)

Population

the study of interactions between members of the same species

Abiotic factors

Non-living physical and chemical elements

Biotic factors

Living organisms

Density-dependent factors

Predation, interspecific competition, intraspecific competition, accumulation of waste

Density-independent factors

weather, natural disasters, pollution, and other chemical/physical conditions

Population demography

quantitative study of populations, how size changes through time, population broken down into parts

Generation times

average birth interval between birth of an individual and birth of its offspring

Cohort

peer group (similarities); think similar ages and life stages

Fecundity

how able a female is to reproduce

Mortality

how many people are being removed from the group

Life table

probability of survival and reproduction through a cohort’s life

Survivorship

percent of the original population surviving to a given age

Survivorship curve

graph of the number of individuals surviving at each age interval

Exponential growth model

applies to populations with no growth limits

Carrying Capacity (K)

maximum number of individuals that the environment can support

Logistic growth

applies to populations as they reach K

Ecological footprint

measures the amount of biologically productive land and sea area of an individual, a region, all of humanity, or a human activity that compete for biologically productive space

Dominant species

most abundant

Keystone species

most influential with respect to trophic levels

Foundation species

allows other species to inhabit an area by altering the environment

Community ecology

the study of interacting populations of species living within a particular area or habitat

Intraspecific Competition

competition within a species

Interspecific Competition

Competition between different species

Competitive Exclusion Principle

two species cannot occupy the same niche in a habitat, different species can’t coexist in a community if they are competing for all the same resources

Niche

total range of conditions under which an individual (or population) lives and replaces itself

Realized Niche

actual set of conditions under which an organism exists

Fundamental niche

entire set of optimal conditions under which an organismic unit can live and replace itself

Resource partitioning

among similar species occupying the same geographic area, result of NS

Predation

Consumption of prey by its predator

Batesian Mimicry

Harmless species imitate warning signals of harmful species

Müllerian Mimicry

Related or unrelated poisonous species that share a predator come to resemble one another’s warning signals

Commensalism

One species benefits and the other is just “meh”

Parasitism

One species is gaining something from the other - one benefit

Mutualism

Both are benefitted

Endoparasites

Live within the body of hosts

Ectoparasites

Live on the surface of hosts

Parasitoidism

Deposit eggs on/in host

Endosymbiont

Live inside another, but usually mutualistic

Richness

number present

Abundance

number of individuals per species

Relative abundance

how common or rare relative to others

Diversity

species richness and evenness of species’ abundances

Evapotranspiration

the release of water into the atmosphere as water vapor, by evaporation, transpiration, and respiration

Autotrophs

Primary producers

Heterotrophs

Consumers

Limiting nutrients

Nutrients in shortest supply and put a limit on growth

Gross primary productivity (GPP)

Rate at which primary producers incorporate energy from the sun

Net primary productivity (NPP)

Energy that remains in primary producers after respiration and heat loss