Across
- 5. a theory that states that the geologic processes that shape Earth are uniform through time
- 6. a trace of an organism that existed in the past
- 9. a mechanism by which individuals that have inherited beneficial adaptations produce more offspring on average than do other individuals
- 12. remnants of organs or structures that had a function in an early ancestor
- 13. the individuals of a species that live in an area
- 14. the process by which humans change a species by breeding it for certain traits
- 15. structures that perform a similar function but are not similar in origin
- 16. a theory that states that natural disasters such as floods and volcanic eruptions have happened often during Earth's long history
- 17. the ability of a trait to be passed down from one generation to the next
Down
- 1. a principle that states that the changes in landforms result from slow changes over a long period of time
- 2. the process of biological change by which descendants come to differ from their ancestors
- 3. features that are similar in structure but appear in different organisms and have different functions
- 4. the study of fossils or extinct organisms
- 7. a feature that allows an organism to better survive in its environment
- 8. a group of organisms so similar to one another that they can reproduce and have a fertile offspring
- 10. the difference in the physical traits of an individual from those of other individuals in the group to which it belongs
- 11. a measure of the ability to survive and produce more offspring relative to other members of the population in a given environment