Can't answer that, but I do know that the common ancestor of monkeys apes and people was able to synthesise ascorbic acid (vitamin C), but that the most recent common ancestor of gorillas, chimps and people couldn't.
You might be interested in William Calvin's research Throwing Madonna. His hypothesis is that it isn't the opposable thumb, it's the ability to accurately throw things. There are a number of reasons I find this interesting:
We do seem to be the only species that can accurately throw stones and sticks to hunt prey animals
If his claim that the number of neurons needed to accurately time the release increases as (IIRC) the square of accuracy required (eg to go from somewhere in a 50th of a second to somewhere in a 100th requires four times as many neurons), this neatly accounts for our lineage's massive brains as necessary for survival
The general ability to sequence accurately-timed events is fundamental to our ability to talk, which is arguably our most distinctive trait. It also is very similar to what's required for long strings of logic, the motions needed for making tools, etc etc.
In another post you claimed that standard biology would require us to have 'growths' that are incipient new organs. This is obviously false. Consider: what organ allows people to read and write? Was it simply growing for the last 200,000 or so years waiting for someone to invent writing? Or was it being used for other purposes during that time, and literacy is a mere side effect of other abilities (like the ones Calvin identifies)?
How do you KNOW this 'fact'?
You might be interested in William Calvin's research Throwing Madonna. His hypothesis is that it isn't the opposable thumb, it's the ability to accurately throw things. There are a number of reasons I find this interesting:
We do seem to be the only species that can accurately throw stones and sticks to hunt prey animals
But sky-diving raptors can move a LOT faster and intercept prey in 3d space with a LOT smaller brains than we have; we who only have TWO dimensions to worry about.
If his claim that the number of neurons needed to accurately time the release increases as (IIRC) the square of accuracy required (eg to go from somewhere in a 50th of a second to somewhere in a 100th requires four times as many neurons), this neatly accounts for our lineage's massive brains as necessary for survival
The general ability to sequence accurately-timed events is fundamental to our ability to talk, which is arguably our most distinctive trait. It also is very similar to what's required for long strings of logic, the motions needed for making tools, etc etc.
In another post you claimed that standard biology would require us to have 'growths' that are incipient new organs. This is obviously false.
How can you say it is false?