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fossil the trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock
evolution process in which organsims change gradually over thousands or millions of years
species group of closely related organisms that can mate to produce fertile offspring
homologous_structure similar structures that related species have inherited from a common ancestor
adaptation trait that changes over time and improves an organisim's ability to survive and reporduce
relative_dating method of estimating the age of fossils based on their position in layers of sedimentary rock in relation to one another
scientific_theory an explanation that ties together many tests and observations - scientists agree on conclusions
variations differences between members of the same species
sedimentary_rock rock that is formed from layers of sediment over time
extinct a species that no longer has any living members
natural_selection process by which individuals that are better adapted to their environment survive and reproduce
fossil_record a historical sequence of life indicated by fossils found in the earth's crust
absolute_dating method of measuring the actual age of an event or object in years
fertile can produce an offspring
sterile unable to reproduce
branching tree diagram that shows how scientists think different groups of organisms are related; cladogram; phylogenic tree
Galapagos_Islands where Darwin observed a variety of species and proposed a theory of biological evolution
overproduction a species creates more offspring than can survive; those who are better able to survive then pass on their genes to their offspring.
infer to reach a conclusion by making observations and using background knowledge
speciation formation of a new species due to evolution
Created by: glennjonesms