| A | B |
|---|
| species | group of organisms that share similar characteristics and can reproduce among themselves |
| evolution | change in inherited characteristics over time |
| natural selection | a process by which organisms with traits best suited to their environment are more likely to survive |
| variation | an inherited trait that makes an individual different from other members of its species |
| adaptation | any variation that makes an organism better suited to its environment |
| gradualism | model describing evolution as a SLOW process |
| punctuated equilibrium | model describing the RAPID evolution that occurs when mutation of a few genes results in a species suddenly changing into a new species |
| sedimentary rock | type of rock that is most likely to contain fossils and is formed when layers of sand, silt, clay are cemented and compacted together |
| radioactive element | element that gives off a steady amount of radiation as it slowly changes to a non radioactive element |
| embryology | study of embryos and their development |
| homologous | body parts that are similar in structure and origin and can be similar in function |
| vestigal structure | doesn't seem to have a function and may once have functioned in the body of an ancestor |
| primate | group of mammals including humans, monkeys, and apes that share characteristics such as opposable thumbs, binocular vision, and flexible shoulders |
| hominid | humanlike primate from millions of years ago that ate both plants and meat, and walked upright on two legs |
| Homo sapiens | early humans that likely evolved from Cro-Magnons |
