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a process by which individuals that are better suited to their environment survive and reproduce most successfully
method of determining the age of a fossil by comparing its placement with that of fossils in other layers of rock (older is usually deeper)
determine actual age of fossil, compare amount of radioactive element in sample to amount of element into which it breaks down
Name for the time in earths early history that accounts for ninety percent of earth's time, but only very simple organisms lived. White Old Boring Cells
the part of geologic time 570-245 million years ago ; invertebrates, fishes, amphibians, reptiles, ferns, and cone-bearing trees were dominant. Yellow Bizarre sea creatures
middle life (245-144 million years ago); rise of mammals and dinosaurs; the rise of birds; extinction of dinosaurs, rise of flowering plants. Red Bloody Dinosaurs
era that began about 65 million years ago, known as the "Age of Mammals" Blue New Hairy
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