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chapter 11
Term | Definition |
---|---|
eon | largest units of geologic time |
eras | eras are subdivided into periods |
periods | periods are subdivided into epochs |
epochs | a division of time that is a subdivision of a period and is itself subdivided into ages, corresponding to a series in chronostratigraphy |
mass extinction | the extinction of many species on earth within a short period of time |
land bridge | connects two continents that were previously separated |
geographic isolation | the separation of a population of organisms from the rest of its species due to some physical barrier such as a mountain range or an ocean |
Paleozoic era | oldest era of the phanerozoic eon |
mesozoic era | middle era of the phanerozoic eon |
cenozoic era | youngest era of the phanerozoic eon |
inland sea | body of water formed when ocean water floods continents |
coal swamp | oxygen poor environment where over time plant material changes into coal |
superconinent | an ancient landmass which separated into present day continents |
dinosaurs | dominant mesozoic land vertebrates that walked with legs positioned directly below their hips |
plesiosaurs |