Alcohol Adaptation

This just found in New Scientist May 14 2011 No 2812.

Vertebrates, which as all of you know includes we humans, had evolved genes to metabolise ethanol 360 million years before flowering plants started producing fruit whose fermentation could produce alcohol. Hector Riveros-Rosas of the National Autonomous University of Mexico City [love that name, makes me want places like Sydney Uni to disclose how non-autonomous it is!] had found that the gene for alcohol dehydrogenase (ADH) [hmm, and there's an interesting acronym in the context of the known impact of alcohol on attention spans] first shows up in vertebrates around 440 million years ago, which is long before flowering plants evolved and also before conifers began producing berries that can ferment and make alcohol. It had previously been thought that the gene evolved in response to the making possible of alcohol.

Now the weird thing is that this gene seems to have been developed to breakdown hormones in us like dopamine and then got 'hijacked for our bacchanalian pleasures', as the article puts it. But of course there is nothing really being hijacked here given that dopamine is released when we indulge in those other accompaniments to Bacchanals - sex, drugs, food, and in more recent times, rock and roll. All that seems to have happened is that this gene that was already having a great time scoffed a fermenting fruit one day and recognised the potential in it for even more pleasure than it was already getting.

The question remains though, given we humans didn't come along until waaaaaaaaaaaay later, which was the lucky vertebrate that hosted the first ADH gene. Having an accountable attachment to it, I hope it was a distant forbear of the coati.