Ecology

Abiotic factor

Abiotic factors are the non-living parts of an organism's habitat.

Allopatric speciation

The formation of new species in populations that are geographically isolated from one another.

Analogous features

share similar function, but not common ancestry

Artificial selection

the selective breeding of organisms by humans for specific characteristics

Asexual reproduction

Process by which a single parent reproduces by itself

Bedrock

the layer beneath the soil, composed of rock

Beneficial mutation

a mutation that benefits the organism

Binomial nomenclature

Classification system in which each species is assigned a two-part scientific name

Biological Oxygen Demand

the amount of dissolved oxygen needed to completely break down the organic matter in a water sample at 20 degrees Celsius over five days

Biome

a large geographical region with a specific range of temperatures and precipitation, and the organisms that are adapted to those conditions of temperature and precipitation

Biotic factor

Any living part of the environment with which an organism might interact

Biotic Potential

the maximum number of offspring that a species could produce with unlimited resources

Canopy

the upper layer of vegetation in a forest

Carrying Capacity

the maximum number of individuals of a species that can be supported by an ecosystem

Clear-cutting

the removal of all the trees in an area

Climate

the average conditions of temperature and precipitation in a region

Convergent evolution

Evolution toward similar characteristics in unrelated species

Deciduous Forest

-warmer temperatures -rich fertile soil -high precipitation 75-250 -deer, bears, poplars -greatest biodiversity in Canada

Density Dependent Factors

a factor in an ecosystem that affects members of a population because of population density (food supply, water quality, sunlight, disease, territory)

Density Independent Factors

a factor in an ecosystem that affects members of a population regardless of population density (fire, flood)

Dichotomous key

An aid that is used to identify organisms and that consists of the answers to a series of questions

Divergent evolution

when two or more species sharing a common ancestor become more different over time

DNA

A complex molecule containing the genetic information that makes up the chromosomes.

Dynamic Equilibrium

earth is continuously changing however it has the ability to balance itself

Ecology

the study of interactions between organisms and their living and non-living environment

Ecosystem

a community and its physical and chemical environment

Ecotone

a transition area between ecosystems

Eutrophic

having high nutrient levels

Fitness

Ability of an organism to survive and reproduce in its environment

Gene pool

Combined genetic information of all the members of a particular population

Gene

A segment of DNA on a chromosome that codes for a specific trait

Genus

A group of similar species

Grassland

-warmer temperatures -rich fertile soil -25-100 low precipitation -grasses, hawks, deer, grasshoppers, etc.

Habitat

the smaller part of a biome in which only certain organisms live

Harmful mutation

a mutation that decreases an organism's fitness

Homologous features

similar features that originated in a shared ancestor

Humus

decaying plant and animal matter

Indicator Species

species that serve as early warnings that an ecosystem is being damaged

Inheritance of acquired characteristics

Lamarck; Traits developed during a parent's lifetime could be passed to their offspring

Interspecific Competition

competition between individuals of different species

Intraspecific Competition

an ecological interaction in which individuals of the same species compete for resources in habitat

Law of Minimum

states that the nutrient in the least supply is the one that limits growth

Law of Tolerance

states that an organism can survive within a particular range of an abiotic factor

Limiting Factor

any factor that limits a populations ability to realize its biotic potential when it nears or exceeds the environments carrying capacity

Limnetic Zone

the area of a lake or pond in which there is open water and sufficient light for photosynthesis to occur

Litter

the upper layer of soil, composed mainly of partially decomposed leaves or grasses

Littoral Zone

the area from the shore of a lake or pond to the point where no more plants grow in the lake bottom

Muskeg

-cold temperatures -short growing season -permafrost layer beneath soil -low precipitation 50-150 -moss and lichens, caribou, etc.

Mutation

A rare change in the DNA of a gene, ultimately creating genetic diversity.

Natural selection

A natural process resulting in the evolution of organisms best adapted to the environment.

Neutral mutation

A mutation that has no effect on survival or reproduction

Niche

an organisms role in an ecosystem, consisting of its place in the food web, its habitat, its breeding area, and the time of day at which it is most active

Oligotrophic

having low nutrient levels

Permafrost

permanently frozen soil

Phylogeny

Evolutionary history of a species

Population Growth Rate

The rate at which the number of individuals in a population increases in a given time period

Profundal Zone

the region of a lake beneath the limnetic zone, in which there is insufficient light for photosynthesis to occur

Selective Cutting

the harvesting of only certain trees from an area

Sexual reproduction

Type of reproduction in which cells from two parents unite to form the first cell of a new organism

Slash-and-burn

the complete clearing of a forest by felling and burning the trees

Speciation

Formation of new species

Species

A group of similar organisms that can breed and produce fertile offspring.

Spontaneous generation

Hypothesis stating that life could arise from nonliving matter.

Subsoil

the soil layer beneath the topsoil, usually containing more rock particles and less organic matter than the topsoil

Taiga

-acidic soil -50-250 precipitation -changeable weather -spruce and pine, bears, moose, etc.

Taxonomy

The scientific study of how living things are classified

Theory of gradualism

The idea that speciation takes place slowly

Theory of punctuated equilibrium

The idea that species evolve rapidly, followed by a period of little or no change

Topsoil

the soil layer beneath the litter, composed of small particles of rock mixed with humus

Understory

below the canopy layer

Vestigial features

Rudimentary structures with no useful function