A study has come out indicating that we might have been right-hand dominant as long as 500,000 years ago.
This is a very significant finding, if true, because it gives us a possible hint as to why we suddenly rocketed to the top of intellectual heap. I've long thought that the only explanation for our intellectual capabilities was the formation of a complex, logical language. Because there was something that was nearly a magic bullet in our evolution. In the geological timespan of a fart, we went from being overgrown chimps to walking on the moon. We had spent the previous 200 million years evolving and didn't do that. We've spent the last 500,000 years evolving with all of our primate cousins, and none of them did that. What was that magic bullet?
The only answer that makes sense is language. Specifically a logical language, whereby we can encode data into a verbal broadcast than can then be decoded and interpreted by an entirely separate brain. Unlike body language, or primal communication like hoots and hollars, the amount of information that can be wedged into complex logical language is multiple orders of magnitude more.
This is why art is usually seen as indicative of modern human thought. It's an internal thought made external through some sort of coding. Some other primates seem to be making strides towards this, like with female orangutans teaching their children, but we're the only ones that definitely did it. If logical language emerged in our common ancestor 500,000 years ago (modern humans emerged about 200,000 years ago, perhaps as long as 300,000), that has implications for Neanderthal study, namely, they likely did have language of some sort.
It would also give us greater insight into the evolutionary magic bullet that produced Mozart, which is a pretty big deal.