Ecology and Evolutionary Biology Review

Vocabulary flashcards for exam review.

Genetic Variation

Diversity in gene frequencies within a population, resulting from differences in DNA sequences.

Mutation

A source of genetic variation in sexually reproducing species involving changes in DNA sequence.

Horizontal Gene Transfer

A source of genetic variation that transfers genetic material between organisms.

Sexual Recombination

A source of genetic variation through meiosis, independent assortment, crossing over, and random fertilization.

Genotypic Variation

Differences in DNA sequences that influence phenotypic variation.

Phenotypic Variation

Observable traits produced by genetic variation, influenced by environmental factors.

Hardy-Weinberg Equilibrium

Conditions for constant allele and genotype frequencies: no mutations, isolation, random mating, large population, no natural selection.

Genetic Drift

Random fluctuation of allele frequencies, especially in small populations, reducing genetic variation.

Gene Flow

Transfer of alleles between populations through migration, increasing genetic variation.

Natural Selection

A mechanism of evolution where individuals with higher fitness are more likely to pass on their genes.

Fitness

An organism's ability to survive and reproduce.

Directional Selection

Favors one extreme trait.

Stabilizing Selection

Favors average traits, reducing extremes.

Diversifying/Disruptive Selection

Favors both extremes, leading to two distinct traits.

Balancing Selection

Maintains genetic diversity, where heterozygotes may have a survival advantage.

Sexual Selection

Traits increase mating success, leading to features like plumage or antlers.

Bottleneck Effect

Population is drastically reduced, causing a loss in genetic diversity.

Founder Effect

Small group starts a new population, carrying only a fraction of the original genes.

Lamarckian Evolution

Traits developed during life are passed on.

Darwinian Evolution

Natural selection drives the mechanisms of evolution.

Artificial Selection

Human-driven selection.

Species Concept

A way to define what a species is, helping scientists determine boundaries.

Evolutionary Lineage Species Concept

Species as a group of organisms with a shared evolutionary path.

Ecological Species Concept

Species defined by its unique role or niche in the environment.

General Lineage Species Concept

Species as a separately evolving population or lineage.

Allopatric Speciation

Speciation that occurs when populations are geographically separated.

Sympatric Speciation

Speciation occurs within the same geographic area.

Hybrid Zone

Areas where separated populations interbreed.

Biological Species Concept

A group of interbreeding natural populations that are reproductively isolated.

Prezygotic Barriers

Barriers that prevent mating attempts.

Postzygotic Barriers

Barriers that act after fertilization.

Ecology

Scientific study of the relationships between organisms and their environment.

Environmentalism

Movement focused on protecting the environment from harmful human activities.

Abiotic Factors

Non-living elements like temperature, water, and sunlight.

Biotic Factors

Living components like plants, animals, and microorganisms.

Organism

A single individual of a species.

Population

A group of individuals of the same species living in the same area.

Community

All populations of different species in a given area.

Ecosystem

A community of organisms interacting with their abiotic environment.

Biosphere

The global sum of all ecosystems.

NPP

Net Primary Productivity; the amount of energy available for plant growth.

Tropical Rainforest

Warm, wet, high biodiversity.

Desert

Dry, little precipitation, sparse vegetation.

Savanna

Grasslands, warm, seasonal rainfall.

Temperate Forest

Mild, distinct seasons, deciduous trees.

Taiga

Cold, conifer forests.

Tundra

Cold, low vegetation, permafrost.

Chaparral

Hot, dry summers, mild wet winters, shrubland.

Ecological Footprint

Estimate of land and water required to sustain one person.

Milankovitch Cycles

Long-term natural changes in Earth's orbit affecting climate.

Biomagnification

Toxins concentrate as they move up the food chain, harming top predators.

Biodiversity

Variety of life on Earth, including genetic, species, and ecosystem diversity.

Biophilia

Innate human connection to nature.

Conservation Biology

Seeks to investigate and reverse the loss of Biodiversity.

Restoration Ecology

Uses ecological principles to help repair degraded areas.

Biodiversity Hotspots

Small areas with high concentrations of endemic and endangered species.

Nature Preserves

Protected areas where plants, animals, and habitats are kept safe.