Evolution

3. When two populations become separated by a physical barrier, such as rivers, mountains, or lake.
7. TWO separate species in different areas evolve to look or behave in a similar manner. Results in Analogous Structures.
8. Gene frequencies change as individuals move in or out of the population.
9. Natural selection gradually changes the average features of a species, making a new species.
11. Gene frequencies change as individuals move in or out of the population.
12. The original population splits into 2 isolated groups which begin to breed among themselves, and genetic changes accumulate over time
14. Organisms with the variation of a trait best suited for their environment will survive and reproduce.

1. TWO species that have a partnership or symbiotic relationship evolve together to continue the relationship.
2. Occurs when 2 populations no longer interbreed.
4. When two populations become separated by a physical barrier, such as rivers, mountains, or lake.
5. two populations become isolated because they reproduce at different times or patterns.
6. ONE species evolves into two different species. Results in Homologous Structures.
10. equilibrium Periods of rapid speciation (formation of new species) followed by long periods of stasis (no change).
13. Pure chance causes a change in the gene pool of a population