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Evolution
| Term | Definition |
|---|---|
| Convergent Evolution | Evolution towards similar features in unrelated species |
| Divergent Evolution | Closely related species that evolve in different directions |
| Coevolution | Species that evolve in response to changes in each other |
| Microevolution | A generation to generation change in allele frequency in a population |
| Homologous | Body parts that are similar (have same structure), but are used differently |
| Analogous | Body parts that perform a similar function, but are not alike in structure |
| Vestigial | Small, leftover body parts that had a function in early ancestors, but have no use today |
| Mass extinction | Happens at global level because of catastrophic event like ice age, volcanic eruption, or asteroid impact |
| Extinction | Elimination of a species |
| Adaptive Radiation | One ancestral species evolves into many descendant species |
| Punctuated Equilibrium | Life changes slowly then periods of quick evolutionary change happen |
| Background Extinction | Extinctions that occur at a continual low rate |
| Stabilizing Selection | Extreme phenotypes eliminated, narrow range of phenotypes |
| Directional Selection | One extreme eliminated, mean reduced |
| Disruptive Selection | Extreme phenotypes favored, mean reduced |
| Normal Distribution | Most of the population is the mean, few extremes |
| Genetic Drift | Occurs when an event drastically reduces a populations size |
| Bottleneck Effect | Change in allele frequencies due to chance |
| Founder Effect | It occurs when a few individuals start a new population |
| Gene Flow | Movement of alleles between populations |
| Behavioral Isolation | Isolation based on differences in courting or mating behaviors |
| Temporal Isolation | Timing prevents reproduction between populations |
| Geographic Isolation | Timing prevents reproduction between populations |
| Allele | Form of a gene |
| Allele Frequency | Measure of how common an allele is in a gene pool or population |
| Gene Pool | All of the alleles of a group |
| Speciation | New species evolves |