Pre-AP Biology Evolution Study Guide

Conditions for Natural Selection

• Three essential elements must be present for natural selection to occur: variation in population, heritability of traits, and differential reproduction or survival.

Fossil Record

• The oldest fossils are found in the deepest layer of the earth's crust.

Vestigial Structures

• Vestigial structures are organs or features that have lost their original function through evolution, but are still present in a reduced form.

Comparative Anatomy

• The pictures of human, horse, cat, bat, bird, and whale arms show similar bone structures, indicating a common ancestor.

Natural Selection

• The main function of natural selection is to favor individuals with advantageous traits, leading to adaptation and evolution.

Genetic Drift

• Genetic drift is the random change in the frequency of a gene or trait in a population over time.

Speciation

• The main outcome of speciation is the formation of new, distinct species that can no longer interbreed.

Geographic Isolation

• Geographic isolation is a barrier that prevents individuals from different populations from interbreeding, leading to genetic divergence.

Hardy-Weinberg Equations

• In Hardy-Weinberg calculations, 'P' represents the frequency of the dominant allele in a population.

Competition

• Organisms typically compete for essential resources such as food, water, light, and space.