| A | B |
|---|
| Over reproduction | Darwin's first observation |
| Stays constant | What happens to the number of most populations over time (2nd observation) |
| Competition | Happens when too many offspring have a limited supply of resources |
| Population | A group of organisms of the same species |
| Variation | Caused by both environmental and genetic differences |
| Genetic | The cause of variation which can be inherited |
| Mutation | The cause of new genetic variation |
| Natural selection | A process which must happen if Darwin's observations are correct |
| Evolution | Change in organisms over a period of time |
| Environmental | Cause of variation which is not inherited |
| Fossil | Evidence of an organism's preserved in rock (usually) after it has completely decomposed |
| Minerals | Often replace the hard parts of animals during fossilisation |
| Peppered moth | Insect often used as an example of natural selection |
| Camouflaged | Dark moths on soot covered bark |
| Flourescent light | Used to attract peppered moths when you want to count how many have survived |
| Extinction | Happens to species which don't adapt to changes in their environment |
| Species | A group of organisms which can mate to produce fertile offspring |
| Charles Darwin | 19th Century scientist who worked out that natural selection could explain evolution |
| Sedimentary | Type of rock which contains fossils |
| Adaptation | A trait which helps an organism to survive |
