Unit 5 Biology

Allopatric Speciation

Speciation from geographic separation.

Adaptation

Trait enhancing survival.

Adaptive Evolution

Increase in beneficial traits.

Allele (gene) Frequency

Proportion of a specific allele.

Assortative Mating

Mating with similar phenotypes.

Behavioral Isolation

Mating prevented by different behaviors.

Bottleneck Effect

Drastic population drop changing alleles.

Convergent Evolution

Different species evolving similar traits.

Divergent Evolution

One species evolving into many.

Founder Effect

Small group starting a new population.

Frequency Dependent Selection

Fitness depends on trait commonness.

Genetic Drift

Random changes in allele frequencies.

Gene Flow

Movement of alleles between populations.

Good Gene Hypothesis

Elaborate traits indicate genetic quality.

Habitat Isolation

Mating prevented by different habitats.

Handicap Principle

Costly traits signal genetic fitness.

Homologous Structures

Similar structures from common ancestors.

Reproductive Isolation

Inability to interbreed successfully.

Selective Pressure

Environmental factors affecting survival.

Speciation

Formation of new species.

Sympatric Speciation

Speciation without geographic separation.

Temporal Isolation

Mating prevented by different timing.

Vestigial Structure

Useless remnant of ancestral structure.

Vicariance

Geographic barrier dividing a population.

Stabilizing Selection

Selection favoring average phenotypes.

Diversifying Selection

Selection favoring extreme phenotypes.

Directional Selection

Selection favoring one extreme phenotype.

Hardy-Weinberg Principle

Allele frequencies remain constant without evolution.

Aposematic Coloration

Warning colors indicating toxicity.

Batesian Mimicry

Harmless species mimics toxic one.

Biotic Potential

Maximum possible growth rate.

Birth Rate

Number of births per capita.

Carrying Capacity

Maximum population an environment supports.

Climax Community

Stable

Commensalism

One benefits

Competitive Exclusion Principle

Two species cannot share exact niche.

Death Rate

Number of deaths per capita.

Density-Dependent Regulation

Limiting factors tied to population size.

Density-Independent Regulation

Limiting factors unrelated to population size.

Fecundity

Potential reproductive capacity.

Foundation Species

Species that shapes an ecosystem.

Intersexual Selection

Mate choice between sexes.

Interspecific Competition

Competition between different species.

Intrasexual Competition

Competition within the same sex.

K-selected Species

Few offspring

Kin Selection

Helping relatives survive to pass genes.

Müllerian Mimicry

Two toxic species mimic each other.

Mutualism

Both species benefit.

Parasite

Organism feeding off a living host.

Pioneer Species

First species to colonize barren areas.

Primary Succession

Life colonizing lifeless rock.

r-Selected Species

Many offspring

Secondary Succession

Life returning after a disturbance.

Species Richness

Number of different species present.

Altruism

Selfless behavior benefiting others.

Abiotic

Non-living environmental factors.

Biodiversity

Variety of life in an ecosystem.

Biogeography

Geographic distribution of living things.

Biomass

Total mass of living matter.

Biome

Large-scale ecosystem type.

Biotic

Living environmental factors.

Chemoautotroph

Organism using chemicals for energy.

Chytridiomycosis

Fungal disease killing amphibians.

Dead Zone

Water area with depleted oxygen.

Ecology

Study of organism-environment interactions.

Ecosystem

Community of interacting organisms and environment.

Endemic

Native to one specific geographic area.

Eutrophication

Excessive nutrients causing algal blooms.

Global Climate Change

Long-term shifts in weather patterns.

Greenhouse Gases

Gases trapping heat in the atmosphere.

Greenhouse Effect

Warming from trapped atmospheric heat.

Gross Primary Productivity

Total energy captured by producers.

Net Primary Productivity

Energy available to consumers.

Tragedy of the Commons

Overuse of shared public resources.

Weather

Short-term atmospheric conditions.