It's still an area of active research. WT and their terribly flawed publications are hopelessly outdated.
I'd suggest that he do his own research. WT is going in a "dumbing down" direction, so if he is interested in the subject, he won't learning anything by only looking at everything through WT goggles.
A couple years ago we were talking about evolution ( which he does not believe in )
If he doesn't believe in evolution, which of the passengers on the ark was infected with AIDS, ebola, measles, smallpox, etc.? He needs to research both evolution and abiogenesis before he draws the line of what he does and doesn't believe in.