Humans and Chimpanzees Diverged About 6 Million Years Ago

question 55

Multiple Choice

Humans and chimpanzees diverged about 6 million years ago.If 12 nucleotide substitutions have occurred between human and chimpanzee lineages in a sequence of mitochondrial DNA and 36 have occurred between humans and gibbons, according to the molecular clock hypothesis, humans and gibbons separated _______ million years ago.

• A) 2
• B) 6
• C) 12
• D) 18
• E) 36

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A form of conditioning where the subject learns to perform a behavior that terminates an aversive stimulus.

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