BIO Vocab Study 4-1-4-4

Evolution

The process by which species change over time through genetic variation and natural selection.

Common Descent

The principle that all living organisms share a common ancestor.

Speciation

The formation of new and distinct species due to evolutionary processes.

Species

A group of organisms that can interbreed and produce fertile offspring.

Adaptation

A trait that improves an organism’s ability to survive and reproduce.

Reproductive Isolation

When different populations can no longer interbreed, leading to speciation.

Behavioral Isolation

When species develop different mating behaviors that prevent interbreeding.

Temporal Isolation

When species reproduce at different times, preventing interbreeding.

Geographic Isolation

When physical barriers prevent species from interbreeding.

Phylogeny

The evolutionary history and relationships among species.

Natural Selection

The process where organisms with advantageous traits survive and reproduce more.

Artificial Selection

The selective breeding of organisms to produce desired traits.

Niche

The role and environment a species occupies in an ecosystem.

Fitness

An organism’s ability to survive and reproduce in its environment.

Struggle for Existence

The competition for limited resources among organisms.

Single Gene Trait

A trait controlled by only one gene.

Polygenic Trait

A trait influenced by multiple genes, leading to a range of variations.

Directional Selection

When individuals with one extreme of a trait are favored.

Stabilizing Selection

When individuals with an average form of a trait have higher fitness.

Disruptive Selection

When individuals with extreme traits are favored over the average.

Fossil

The preserved remains or traces of ancient organisms.

Fossil Record

The collection of fossils that provides evidence for evolution.

Relative Dating

A method of determining a fossil’s age by comparing its position in rock layers.

Index Fossil

A fossil used to help determine the relative age of rock layers.

Radioactive Dating

A technique that uses radioactive decay to determine a fossil’s exact age.

Half-Life

The time it takes for half of a radioactive substance to decay.

Paleontologist

A scientist who studies fossils to learn about ancient life.

Homologous Structure

Body parts in different species that have a similar structure but may serve different functions, indicating common ancestry.

Vestigial Organ

A body part that has lost its original function due to evolution.

Mass Extinction

A rapid and widespread decrease in the number of species on Earth.

Geologic Time Scale

A timeline of Earth’s history based on major geological and biological events.

Macroevolution

Large-scale evolutionary changes that occur over long periods.

Adaptive Radiation

The rapid evolution of many species from a common ancestor to fill different ecological niches.

Convergent Evolution

When unrelated species evolve similar traits due to similar environments.

Coevolution

The process where two species evolve in response to each other.

Gene Pool

The total genetic material within a population.

Genetic Drift

Random changes in allele frequencies that affect small populations.

Founder Effect

When a new population is established by a small group, leading to reduced genetic variation.

Relative Frequency

The proportion of a specific allele in a gene pool.

Genetic Equilibrium

A state where allele frequencies in a population remain constant over time, meaning no evolution is occurring.