| A | B |
|---|
| paleontologist | scientists who study fossils |
| fossil record | information about past life that existed on earth |
| extinct | species that no longer have living examples |
| relative dating | determining age of fossil by comparing its placement with fossils in other layers of rock |
| index fossil | distinctive fossil used to compare the relative ages of fossils |
| half-life radioactive dating | calculate age of fossil based on the amount of remaining radioactive isotope it contains |
| geological time scale | scale used by paleontologists to represent evolutionary time |
| microfossil | a fossil of microscopic organism such as bacteria |
| endosymbiotic theory | theory that eukaryotic cells were formed by several prokaryotic cells that "united" to increase their survival chances |
| mass extinction | event in which many types of living things became extinct at the same time |
| macroevolution | large scale evolutionary changes tat take place over long periods of time |
| adaptive radiation | process by which a single species or group of species evolves into several different forms that live in different ways |
| convergent evolution | process by which unrelated organisms independently evolve similarities when adapting in similar environments |
| coevolution | process by which two species evolve in response to changes in each other (i.e. insects & flowering plants) |
| punctuated equilibrium | evolution pattern in which long periods of no change are interrupted by brief periods of very rapid change |
| gradualism | evolution pattern in which change take place very slowly over very long periods of time |
