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Gr 8 Unit 3b Geologic Time
the longest division of geological time
a major division of geological time that is usually divided into periods
unit of geologic time into which eras are subdivided, they are divided into epochs
the shortest division of geologic time marked by distinctive features, events, and organisms.
event during which many species become extinct during a relatively short period of time
a landform that connects two continents that were previously separated
occurs when a population, separated by geologic barriers, adapt differently than similar populations in a different environment
the part of geologic time from the formation of the Earth through the rise of simple life forms
the part of geologic time when invertebrates, fishes, amphibians, reptiles and ferns were dominant
the part of geologic time when dinosaurs flourished and then became extinct
the current era of geologic time that began about 66 million years ago; it is known as the "Age of Mammals"
body of water formed when ocean water floods continents
an oxygen-poor environment where, over a period of time, decaying plant material changes into coal
single landmass once formed by all of Earth's continents