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![]() ![]() ![]() ![]() ![]() ![]() ![]() First | Previous | Next | Last | | Index | Home Slide 29 of 109 In the late 1980's and early 1990's a number of studies were done examining the mitochondrial DNA (mtDNA) of women all over the world. These studies, nicknamed the "Eve theory," suggested that the last common ancestor of modern man (actually women) appeared within the last 200,000 years (1-4), much more recently than previously thought. Refinements in the measurements lowered the original estimates to 135,000 years (4) and finally 100,000 years (5). Scientists chose to examine mtDNA because, being enclosed within the subcellular organelle called the mitochondrion, there is no genetic recombination (males make no contribution of mtDNA to the fetus). All mtDNA comes from our mothers and is passed down from mother to daughter, since only mitochondria from the egg are used to make up the fetus. By tracing the differences in mtDNA from peoples around the world, scientists have calculated the probable date of the last common ancestor of modern humans at 100,000 to 200,000 years ago. References
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Last Modified June 21, 2006