Yup. Makes sense. Other animals eat fermented fruit all the time so it stands to figure apes would too. Squirrels get drunk all the time.
The monkeys probably got bored of all the mild intoxicants in the trees. Figured they should try something new and found a whole forest floor of drugs along with alcohol.
Just want to point out that this adaptation related to ethanol metabolism far pre-dates the emergence of terrestrial among hominins. The fossil record indicates that the hominins really began to spend significant amounts of time o.... However,the anatomy of A. ramidus suggest that even at this late date hominins were still spending significant amount of time in the trees. There is not evidence that hominds were terrestrial around 10 mya, and the authors only base this suggestion on the fact that fruit on the forest floor typically contains more ethanol. Thus, the development of alcohol metabolism should correlate with the development of a terrestrial adaptation. However, this a rather weak argument as fermented fruit can also be found on trees, a point the authors do not dispute, and thus this adaptation need not be related to hominids becoming more terrestrial.
Edit: coherence, spelling, and grammar
What? We can't have evolved from anything modern because it takes hundreds of thousands of years for evolution to happen. But yeah, before there were humans and chimpanzees there was probably one ape-like being that doesn't exist today.
The point of the article was that a single mutation in the alcohol dehydrogenase gene around 10 million years ago made our ancestors able to break down ethanol more efficiently, meaning at that point they were probably encountering more ethanol in the environment. That's also around the time our ancestors left the trees and adopted a more terrestrial lifestyle.
Edit: /u/Comoquit makes a good point about the timing of our ancestors transition from arboreal to terrestrial lifestyle
Except for the DNA we share. Stuff like retroviruses are pretty cool. Basically they're viruses that re-encode our DNA to make them fit into it, and they somehow got into the human genome.
Only problem is when this was done we weren't even human, it was before humans existed, and now we can see the same retroviruses, in the same places, in other primates like chimps.
I think of that term to just mean the time period in which apes were gradually spending more time on the ground until the first generation that did not climb a tree
It's probably easier to walk around drunk than to swing from tree to tree.
causation for the evolution of bipedal primates: booze.