Evolution

2. had different shaped beaks depending on the island they were from
7. when a species splits into a number of new forms when a change in the environment makes new resources available or creates new environmental challenges.
9. the study of fossil remains or other clues to past life
10. father of evolution
12. organs that serve no useful function in an organism
13. reduce the fitness of a hybrid offspring
15. the structures evolved independently
16. the most common way for one gene pool to become isolated from another.
17. the name of Darwin's book; the ___ of species
18. required for new species to form
20. the name of the ship that Charles Darwin traveled on

1. refers to the variety of living things
3. Charles Darwin’s theory of evolution states that evolution happens by what?
4. structures that are similar
5. the formation of new and distinct species in the course of evolution
6. when organisms disappear from the earth
8. when two species evolve together
11. a characteristic that helps an organism survive
14. Darwin collected the preserved remains of ancient organisms, called ____
19. a well-supported testable explanation of phenomena that have occurred in the natural world