| A | B |
|---|
| Charles Darwin | British scientist who developed theory of natural selection |
| mutation | a spontaneous change in a gene |
| genotype | the genes possessed by an individual |
| phenotype | the traits expressed by an individual |
| HMS Beagle | a British research ship that conducted a 5 year voyage of exploration in the 1830's |
| Galapagos Islands | a small group of islands in the Pacific Ocean west of Equador |
| species | a group of similar organisms that can mate with each other and produce fertile offspring |
| mule | a sterile hybrid of a female horse and jackass |
| hinny | a sterile hybrid of a female ass and a male horse |
| adaptation | a trait that helps an organism survive and reproduce |
| evolution | the gradual change in a specie over time |
| natural selection | the process by which individuals better adapted for their surrounds survive and reproduce at a higher rate than those less suited for their environment |
| geographic isolation | when a natural barrier such as a mountain range, deep canyon, or body of water separates one population of a species from another, preventing interbreeding |
| continental drift | the movement of the large land masses over millions of years due to plate tectonics |
| fossil | evidence of prehistoric life preserved in the Earth |
| petrified | living material turned to mineral |
| mold | fossil type that is a hollow space in a stone where an organism once was |
| sedimentary rock | type of rock formed by small particles being deposited by wind or water |
| cast | fossil type where a mold is filled with minerals making a copy of the shape of an organism |
| relative dating | determining the age of a fossil compared to another |
| absolute dating | using radioactive elements to determine the actual age of a fossil |
| extinct | when there are no surviving members of a species |
| fossil record | all the millions of fossils that have been collected |
| half-life | the time it takes for one-half of the mass of a radioactive element to decay to a stable daughter element |
