…even if the offspring are sterile? Let’s say that potentially viable zygotes were only created maybe 50% of the time. Are we talking 40k years? 400k?
The simple answer is that such is unknowable, barring significant advancements in temporal displacement technologies.
Last night.
it was a helluva party!
It’s still uncertain how far back the species Homo sapiens goes. I’ve seen estimates ranging from 150,000 - 500,000 years. By definition, offspring would be viable anywhere within the species.
Nobody is quite sure yet which species is our immediate ancestor. Even if you limit the question to those other species assumed to be in our line, I’m pretty sure the answer still is: nobody knows. There’s no DNA from any other Homo species except Neaderthalis, whose ancestry to us is very much in dispute. And they are not thought to back beyond 200,000 or so years, so even if they could interbreed you don’t get any extra mileage out of them.
My bolding.
I’m not sure I understand this, but it sounds like you are proposing that Modern Humans and Neanderthals shared a common ancestor 200k years ago. The DNA analysis done so far indicates a common ancestor about 500k years ago, maybe even more.
As for the OP, the answer is simply: No one knows for sure. It would be very surprising, though, if it were 40k years, since there is no evidence that we’ve changed in any meaningful way since then.
I’ve always heard that it’s possible for modern humans to breed with modern chimpanzees, though it might have to be done artificially, and the offspring would probably be sterile. Given that, I don’t see why we couldn’t breed with “ancestors” that were over a million years old, since they’d be about as different from humans as chimps are now. At the very least, we could probably reproduce with Homo habilis, which existed roughly two million years ago.
Where did you “always hear” this? No self-respcting scientist would make that unsupported asertion.
It would be interesting if we could interbreed with Homo floresiensis. This is truly a stunning discovery! I figured I post it here just as an FYI.
Stunning, indeed. So stunning that I’ve a hard time believing it’s a genuine story. I even checked the date, in case it would be an old article published on april 1st.
Sorry if I was unclear. There are still paleontologists who insist, primarily upon the evidence of a “mixed” skeleton, that Neanderthals and Sapiens could interbreed.
http://cogweb.ucla.edu/ep/Neanderthal.html
My point, however, is that this doesn’t tell us anything about how long ago sapiens could interbreed, because neanderthalis appears in the record after sapiens. Whether they are ancestral to us or we share a common ancestor is irrelevant to this discussion.
And I honestly thought that your Homo floresiensis link was an April Fool’s joke I had missed. (As did others, on preview.) It’s not. Wow. Wow, wow, wow, wow, wow.
I’d had heard rumors of this info before, but nothing this definitive.
Even better one from National Geographic, which will run a special on it next year.
Nature is putting up free links.
It was actually that story that got me a thinkin’.
It wasn’t from a scientist or anything. It was just something that I’ve talked about with people. We all seemed to think that it was probably possible, judging from the fact that humans and chimps are as similar as donkeys and horses (which interbreed).
On another note, “wow” indeed.
If we accept the Out of Africa theory for H. sapiens, then those guys would be about 2M years removed from us, assuming they are decendents of the earliest H. erectus group(s) that left Africa long before modern humans evolved there.
If you’re interested, you might want to do a search (once you become a member). We’ve debated that topic a bunch of times and there’s some good info to be found here. Bottom line, though, there is no direct evidence that humans and chimps can interbreed.
And just FYI, you should be careful about stating personal opinion as fact in GQ. People generally expect you to know what you’re talking about here unless you make it clear that you’re just sepculating.
There was a Discovery Channel special called “Manzee” that detailed the possibility of such a thing, eye witness accounts, etc., and then they basically said it was all bs in the last 5 minutes. Pissed me off.
Not true. That program (it was called “Humanzee”, not “Manzee”) was about one specific animal “Oliver” who was presented by some folks as a Humanzee (half Human half Chimpanzee).
FYI, the best part of that show was the film clip of the Liger-- half lion half tiger. That was on big MoFo of a beast!
Humanzee, that’s right. I knew there was something wrong with Manzee. But I don’t think I was too off with the gist. Sketchy evidence for Oliver’s humanzee pedigree was offered for most of the show, and in the last 5-15 minutes they had experts debunk it all. There was also reports of sightings in China or something like that.
There’s also no definite evidence that they can’t. (Though in my opinion it’s unlikley.)
Yeah, we’ve been down that road often. (Though in my opinon it should be possible under some laboratory conditions. 
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