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Biology Chapter 12

relative dating estimate of the age of a fossil based on the location of fossils in strata
radiometric dating technique that uses the natural decay rate of isotopes to calculate the age of material
isotope form of an element that has the same number of protons but a different number of neutrons as another element
half-life amount of time it takes for one of the isotope in a sample to decay into its product isotope
index fossil fossil of an organism that existed during only specific spans of geologic time across large geographic areas
era second largest unit of geologic time; lasting tens to hundreds of millions of years and consisting of two or more periods
period unit of geologic time that lasts tens of millions of years and is associated with a particular type of rock system
nebula rotating cloud of gas and dust
cyanobacteria bacteria that can carry out photosynthesis
endosymbiosis ecological relationship in which one organism lives within the body of another
primate mammal with flexible hands and feet, forward-looking eyes, and enlarged brains relative to body size
prosimian oldest primate group that includes mostly small, nocturnal primates such as lemurs
anthropoid humanlike primate
hominid primate group that includes orangutans, chimpanzees, gorillas, and humans, as well as their intermediate ancestors
bipedal animal that walks on two legs
Created by: ShullM22



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