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Changes Over Time

Absolute Dating The technique that allows scientists to determine the actual age of a fossil.
Adaptation Any trait that helps an organism survive and reproduce.
Geographic Isolation When species are separated for a long time, a new species may form.
Species A group of similar organisms that can mate and produce fertile offspring.
Branching Tree A diagram that shows how different groups of organisms are related.
Variation Any difference between individuals of the same species.
Mold An empty space that forms when an organism buried in sediment dissolves.
Homologous Structure Similar structures that related species have inherited from a common ancestor.
Fossils The preserved remains or traces of organisms that lived in the past.
Relative Dating A technique used to determine which of two fossils is younger and which is older.
Evolution The gradual change in a species over time.
Natural Selection The process by which individuals that are better adapted to their environment are more likely to survive and reproduce.
Overproduction When a species creates more offspring than can possibly survive.
Petrified Fossil When minerals replace all or part of an organism.
Created by: sikkwl