Found in slashdot thread about the plans for the sequencing of the Neanderthal Genome:

Re:Shouldn't be too hard (Score:4, Funny)

by Rei (128717) Alter Relationship on Wednesday July 06, @04:33PM (#12997429)
(http://www.cursor.org/)

Back in their day, all they had were AMP and ADP; ATP hadn't been invented yet. In those times, glycolysis took two glucose for every one ADP produced, and they were proud of it! Back then, everything ate up that precious ADP - even the Calvin cycle. Oh, sure, it violated their ability to continue on as lifeforms indefinitely, but it was all they had to work with.

Back then, oxygen didn't end up making it into the bloodstream and then to the cells and mitochondria through diffusion from concentration differentials across membranes; they had to put it in manually. It got tiring after a while, all of the precision injection work, but it gave them exercise - a good muscle builder, it was. And, boy, did they need that muscle tone to hunt, what with only being able to synthesize two of their amino acids on their own.

We've come a long way, my friend. A long way.