APES: Ecology and Evolution Terms

Abiotic factors

Non-living chemical and physical parts of the environment that affect living organisms and the functioning of ecosystems

Background extinction

normal extinction rate

Mass extinction

Short period of time in which a high percentage of species dies out

Adaptation

Traits that lead to better reproductive success will be passed on

Fossil record

history of life as documented by fossils

Artificial selection

An evolutionary process in which humans consciously select for or against particular features in organisms

Generalist species

can eat everything (cockroaches, grizzly bear, humans)

Biodiversity

All the different kinds of life you'll find in one area

Habitat

An environment that provides an organism or species with the means to live, grow, and reproduce

Biome

All similar ecosystems around the planet

(Broad, regional types of ecosystems with distinct communities and conditions) 

Immigration

Movement of individuals into an area

Biosphere

The worldwide sum of all ecosystems (zone of life on Earth)

K-selection

Small numbers of children, parents care for an extended time, some will almost always survive but if conditions are right population will not rise that fast

(Humans, bears, eagles, most birds and mammals)

R-selection

Large number of children, many die but there are many more that will survive (because of large numbers), low survival rate but lots of babies that survive in good conditions 

(Cockroaches, fish, most reptiles, mice)

Limiting factors

Anything that constrains a population's size and slows or stops it from growing

Density dependent factors

Force that affects the size of a population of living things in response to the the number of individuals per unit area

(disease, competition, and predation)

Density independent factors

Affect the population of organisms but not restricting them to be at or within a certain number, range, or density

(Food or nutrient limitation, pollutants in the environment, and climate extremes)

Carrying capacity

Population size of a particular species that an area can sustain over time (may be temporarily exceeded, but not for long)

Community

All populations of species found in one area

Natural selection

Strongest characteristics will be passed on (survival of the fittest)

Competitive exclusion

Two species that compete over the same resources and feed on the same species

Niche

Particular conditions and location where something survives, and what it does

Divergent evolution

When related species become more different than expected

Convergent evolution

when unrelated species become very similar usually by adapting to similar habitats or niches

Phylogenetic tree

A diagram that represents evolutionary relationships among organisms

Ecology

The branch of biology that deals with the relations of organisms to one another and to their physical surroundings. (study of connections in nature)

Population

Group of individuals of a species that live in a particular region at a particular time

Ecosystem

A community where different populations of species interact with each other and with their nonliving environment

Resource partitioning

Taking advantage of different resources than other similar species (feeding on different things, or in different places, or at different times)

Ecotourism

Tourism that centers around awareness of the environment and the local community

Selection pressure

Pressure from environment to evolve in a certain way

Directional pressure

Shifts in one direction

Stabilizing pressure

Organisms become more similar to each other

Emigration

movement of individuals out of an area

Specialist species

Require a very specific resource habitat, or food based, and are usually very good at taking advantage of it

(they often go extinct without the specific resource)

Endemic species

species found in a limited area

Speciation

process of new species evolving

Exotic species

anything not normally found in a location

Species

particular type of organism that’s population shares characteristics and can breed

Keystone species

Species that has much bigger impact to their food chain than you’d expect

(Wolves in yellowstone, beavers, tigersharks, elephants, parrotfish)

Endemic species

species found only in a very limited area (Kiwi, south florida pine)

Indicator species

May be used to quickly assess the healthy an ecosystem is (wood frogs in northern forests, sharks on coral reefs, wood storks in everglades)

Exotic/invasive species

Non-native to the ecosystem (usually brought in by humans) that disrupt ecosystems

exotic species

only from another place

invasive species

from another place AND harmful