Across
- 3. Darwin called breeding only animals with the best traits _ selection
- 5. An inherited characteristic that increases an organism’s chance of survival
- 7. The survival of the fittest was referred to as natural _ by Darwin
- 8. Darwin discovered that all the brown birds he had collected were actually all _
- 9. Animals with higher “fitness” survive and reproduce more successfully, this is known as survival of the _
- 10. The principle of common _ tells us that every species ever has come from common ancestors
Down
- 1. When Alfred Russel _ sent Darwin a short letter about evolution, he finally thought he had an incentive to publish his work
- 2. Darwin argued that life has been evolving for _ of years
- 4. Darwin did not publish his thoughts about early on because it _ fundamental scientific beliefs at the time
- 6. Darwin called the ability of an individual to survive and reproduce in its environment _