| A | B |
|---|
| acquired characteristics | traits that an organism developsduring its lifetime |
| adaptation | an inherited trait that promotes survival and reproduction for a species; the process of becoming better suited to the enviroment |
| adaptive radiation | evolution of many diverse groups from a common ancestor |
| convergent evolution | a type oof evolution in which distantly related species produce descendants that resemble each other |
| embryo | an ealry stage of developing organism |
| embryology | the study of an organism's development from zygote or fertilized egg stage |
| epoch | a sybdivision of geologic time |
| era | a large division of geologic time composed of one or more periods |
| evolution | the theories concerning the process of biological and organic change in organisms such that descendents differ from their ancestors |
| evolve | to change from one to another |
| extinct | organism that no longer exist on earth |
| fossil | an imprint or remains of an organism that lived long ago |
| geographic isolation | the division o seperation of a population by a physical barrier such as a mountain range |
| half-life | the average time it takes for one half of a sample of radiactive atoms to undergo radioactive decay |
| heterotroph | an organism that cannot make its own food and must take in nourishment from its enviroment |
| hypothesis | a possible explanation for a set of observation |
| homologous | having similiar structure and orgin but having different functions in various species term used to describe the chromosomes of a matching pair |
| natural selection | the process by which better adapted organisms survive and reproduce |
| period | a unit of geologic time that is a subdivisionof an era |
| reproductive isolation | a barrier to interbreeding caused by varied breeding times or geographical factors |
| sedimentary rock | treteert rtretreter trer |
| speciation | rewrewrew rwerewt5ty rtr |
| stabilizing selection | rwerew wrewerew ewrwer |
| vestigial organ | fsdfs rewrtwe rewre |
