Unit 10 Evolution Study Guide

A comprehensive set of vocabulary flashcards covering Darwin's theory of evolution, mechanisms of natural selection, types of evidence for common ancestry, and the genetic processes affecting population evolution.

Evolution

The change in allele frequencies over time.

Natural Selection

A process occurring in a population when more offspring are produced than can be supported, heritable variation exists, and differential fitness allows some individuals to better compete for limited resources.

Homologies

Molecular, anatomical, and developmental similarities inherited from a common ancestor.

Genetic Drift

A process of evolution that involves changes in the gene pool of a population due to chance.

Gene Flow

The movement of genes into or out of a population.

Mutation

A process that results in changes in the genetic material and contributes to the evolution of a population.

Hutton and Lyell

Scientists who described geological change, contributing to the ideas that influenced Darwin.

Lamarck

A scientist who developed an early theory about how species evolve over time.

Malthus

A scientist who proposed a theory of population growth that influenced Darwin's thinking.

Descent with Modification

Darwin's principle that living species are descended, with changes, from common ancestors.

Homologous Structures

Structures shared by related species that have been inherited from a common ancestor.

Analogous Structures

Body parts that share a common function, but not structure or an evolutionary origin.

Vestigial Structures

Inherited structures that have lost much or all of their original function due to different selection pressures.

Biogeography

The study of where organisms live now and where they and their ancestors lived in the past as evidence of evolution.

Embryology

The study of early developmental stages of organisms used as evidence for common ancestry.

Biochemistry

Molecular evidence, such as DNA and proteins, used to support the theory of evolution.

Gene Pool

The collective genetic information, including all alleles, contained within a population.

Genetic Variation

The differences in DNA among individuals or populations, introduced through mutation, genetic recombination, and lateral gene transfer.

Single-gene Trait

A trait controlled by only one gene, determining how a phenotype is expressed.

Polygenic Trait

A trait controlled by two or more genes, leading to a wide range of phenotypes.

Stabilizing Selection

A form of natural selection in which individuals near the center of a distribution curve have higher fitness than individuals at either extreme.

Directional Selection

A form of natural selection in which individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end.

Disruptive Selection

A form of natural selection in which individuals at the upper and lower ends of the curve have higher fitness than individuals near the middle.

Bottleneck Effect

A change in allele frequency following a dramatic reduction in the size of a population.

Founder Effect

The change in allele frequencies as a result of the migration of a small subgroup of a population.

Genetic Equilibrium

A condition in which allele frequencies in a population remain the same.

Speciation

The process by which a new species evolves.