Hey, how did we get here and who do we have to thank?
June 15, 2012 11:53 AM Subscribe
How many generations am I (or you) the product of? That is, how long is the continuous sequence of paired organisms in the chain of reproduction for a human in the 21st century?
posted by cincinnatus c to science & nature (8 answers total) 4 users marked this as a favorite
A mind-boggling thought, for those of us who might live childlessly, is that the generations before us that have successfully produced offspring go back hundreds of millions of years, with no exceptions. That is, our family trees contain unbroken sequences of reproduction all the way back to the swamp. Anyone who does not have children will be the first of their line to not do so since at least the Devonian period.
Is this correct?
If so, is it possible to estimate the number of generations that have reproduced in order to bring us here? Would any estimate be meaningful?
Furthermore, how far back is it possible to go in identifying our ancestors?
For example, is there a commonly accepted chain that looks something like this:
(single-celled organisms) > (?) > (trilobites or something?) > (?) > (fish?) > (primitive amphibians?) > (?) > (?) > (?) > (mammals) > (primates) > (us!)
Please fill in the ?s, if you can, or provide a better-informed sequence!