| A | B |
|---|
| slight difference in a population | variations |
| variations | different phenotypes in a species |
| trait that helps you survive | adaptation |
| adaptation examples | turtle shell, snake venom, feathers |
| natural selection | major cause of evolution |
| best variations survive and reproduct | natural selection |
| competition | struggle for limited resources |
| environmental pressure | something that can harm or kill you |
| kills members of a population | environmental pressure |
| examples of environmental pressures: | disease, predators, drought, floods, fires |
| causes of variations in sexual reproducers | meiosis (crossing-over) & fertilization |
| only cause of variations in asexual reproducers | mutation |
| ability to live long enough to mate | reproductive success |
| reproductive success | ability to pass your genes to next generation |
| natural selection can cause ___ | new species to form from a common ancestor |
| a common ancestor | closely related organisms share ___ |
