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Ch 8

The History of Life on Earth

fossil the solidified remains or imprints of once living organisms
relative dating a method of estimating how old a rock or fossil is compared to other rocks or fossils
absolute dating a method of learning the age of fossils in years
geologic time scale a calendar used by geologist to divide the Earth's history
extinct when species die out completely
plate tectonics the theory of how plates moved
precambrian time the longest part of earth's history which lasted from the time Earth formed (4.6 billion years ago) until about 542 million years ago
Paleozoic era the second longest part of the Earth's history beginning about 542 million years ago and ending about 251 million years ago
Mesozoic era the middle life period that lasted from about 251 million years ago to 65.5 million years ago
Cenozoic era the recent life era which began about 65.5 million years ago
primate a group of mammals that consist of humans, monkeys, and apes
hominid humans and their human like ancestors
australopithecine early apelike hominids
neanderthal recent hominids that hunted large animals, made fires, and wore clothing,
Created by: swhite2015