[AntiGuv]

I wonder if anyone on this thread can come up with an explanation.

The explanation is that it probably didn't make much, if any, practical difference to their ability to eat, and therefore had no impact on their ability to reproduce. Many people misconstrue evolutionary science to state that any mutation that is less clearly adaptive than another - however trivial and inconsequential to survival - will not perpetuate due to that initial reduction in fitness.

That is false. It's unfortunate that an anthropologist makes such an elementary error.

[Modernman]

Many people misconstrue evolutionary science to state that any mutation that is less clearly adaptive than another - however trivial and inconsequential to survival - will not perpetuate due to that initial reduction in fitness.

Survival of the adequate? Actually, I see your point. If no other mutations were to ever occur, the primates with the stronger jaws would probably outlast the primates with the weaker jaw, over a number of generations. However, since other mutations do occur, the primates with the weaker jaws are in a position to profit from them, in the genetic long-run.

[explodingspleen]

The explanation is that it probably didn't make much, if any, practical difference to their ability to eat, and therefore had no impact on their ability to reproduce. Many people misconstrue evolutionary science to state that any mutation that is less clearly adaptive than another - however trivial and inconsequential to survival - will not perpetuate due to that initial reduction in fitness. That is false. It's unfortunate that an anthropologist makes such an elementary error.

Well, if that applies here then how did the jaws evolve that way in the first place? According to what you have said, there should be no selective pressure to develop such a jaw. But if there is selective pressure, then the original contention is justified.

You can't have your cake and eat it too.

[kkindt]

In the first place there is no proof this is actually a mutation. We have a gene that is similar to that of an animal. But there is a difference. So the difference is chalked up as a mutation??? What kind of thinking is that? Not logical thinking but ideological with the built in assumption that a similar gene must have resulted from a mutation. No actual observation of this happening but because evolution MUST have happened then that's the onlyh explanation there can be for a similar gene existing in one kind of being compared to another.