Natural Selection
| ^^Evolution^^ | ^^Microevolution:^^ | ^^Macroevolution^^ |
|---|---|---|
| Change in inherited traits of a population over time. | Small changes within a population or species over a short period of time. | Large changes within an organism over a long period of time. |
==Two theories Darwin Debunked:==
- that the earth is unchanging
- The Earth is way older than we think
Gene Pool: collection of genes (alleles) in a population at any one time.
Population: group of individuals living in the same place at the same time who are the same species
==non-random changes:== sexual selection, natural selection, artificial selection.
==Random changes:== mutations, genetic drift, and genetic flow
^^Natural Selection “Survival of the fittest”^^
- individuals who are better at surviving and reproducing will get to pass on their genes to the next generation.
^^4 points of natural selection :^^
- Variation: light→ dark, immune vs. not immune etc.
- Selective Pressure: overpopulation, food shortage. Instances that cause certain organisms to have an advantage over other organisms.
- Environment Selection: environment favours a certain organism
- reproduction and inheritance: the variation passed to the next generation.
^^Adaptions:^^
behavioural or structural or physiological features that make an organism better suited to its environment.
For Panthers :
| ^^Structural Adapations:^^ | ^^Behavioural Adaptions^^ | ^^Physiological Adaptions^^ |
|---|---|---|
| Black fur: helps them hide | Like to live alone (makes hunting food easier) | Produce a lot of black pigment: which is why their fur is black. |