I meet my greatx10 to the 20th grandmother, things happen. What happens?

April 8, 2009 12:53 PM

Disturbed-that-I-Keep-Wondering-This-Filter: I keep wondering if I were transported back in time, to different points of human history, could I reproduce with the ladies of the, erm, period?

Say my time machine takes me back to 15 B.C. or so. I meet a swell Sumarian, things get weird. She forgets to drink her magical birth control herbs. Does she get pregnant? Is there anything that's happened evolutionarily, microbiogically, or otherwise that would either prevent her from getting her pregnant, make one or the other of us sick or harm the baby in her womb? What if I went back 10,000 years? Are there DNA implications because I suppose chances that I'm mating with one of my own ancestors are pretty good.

I'm really not sure why I keep thinking about it, but I do.

posted by sully75 to science & nature (19 comments total)

Bring the condoms, Casanova. You'd be fertile with anything from about 200,000 BC onwards.
posted by Aquaman at 1:02 PM on April 8, 2009 [8 favorites]

Feel free to travel back in time and fornicate and procreate in good conscience.

3500 years is not even a twitch in evolutionary time. The only changes that have occurred to the human species are due to diet and improved medical care. But our DNA has remained the same... we're not even a different species (like dogs and wolves).

Are there DNA implications because I suppose chances that I'm mating with one of my own ancestors are pretty good.

Well, in places you can marry your own cousin, which is workable. If you traveled back in time whoever you decided to knock up would be far more removed than your own second cousin today (hopefully you aren't thinking about having sex with her).

Interestingly enough, women in hunter-gatherer societies (or cultures with less access to high calorie food) probably menstruated less, and were less fertile than women are today. Plus, until recently, women breastfed their babies, and breastfeeding also inhibits fertility (and arousal). So you would be totally safe.

However, time travel devices do possess known risks, which include sterility.
posted by KokuRyu at 1:06 PM on April 8, 2009 [2 favorites]

Well, the ultra-simple layman's wikipedia answer is that, given
- a "species" is a biological classification that, very roughly, means a group that can interbreed ^[1], and
- your species "homo sapiens" is believed to have originated around 200,000 years ago ^[2]
You should have no problem commingling your DNA with hers, as long as you take her out to a nice dinner first.
posted by churl at 1:09 PM on April 8, 2009 [1 favorite]

Given a mostly endogamous group, everyone alive about a thousand years before either has no currently living descendants, or is an ancestor to everyone currently alive. It breaks down about 80%/20%: of the people in your population group, 1000 years ago, 80% are ancestors and 20% have no surviving descendants. So if you went back 1000 years, and to your ancestral group, 4 of 5 of the women there would be your ancestors.

You dirty mutha'.
posted by orthogonality at 1:15 PM on April 8, 2009 [1 favorite]

Well I'm no microbiologist, but it is indeed possible that you could be carrying a disease, or a varient of a disease that didnt exist back then (HIV/AIDS being a really obvious one) that could injure the object of your desire. Not so much an issue of pregnancy but of health in general. The human species has adapted through the millenia to all kinds of nasty bugs and bacteria. What we blow off as the common cold now could damn near kill someone 10,000 years ago, just as much as one of their flu bugs that died out in our population centuries ago (and you have no immunity to) could do a number on you.

Bring a bunch of broad spectrum antibiotics when you set off to satisfy your need for procreation and extratemporal lust ;-)
posted by elendil71 at 1:18 PM on April 8, 2009

Here's the next question you need to worry about. What with your excellent nutrition and all, you'd probably be considerably taller than most B.C.E. women. Like, way taller than the height differential between you and 99% of contemporary women (right, scientists? I'm guessing here). Sooooo... you have to ask yourself: would your bedroom skills be up to the challenge? I mean, she might decide your fumbling attempts bespeak a basic lack of coordination, and jump off the bearskin to go in search of better genes. It's worrying!!
posted by artemisia at 1:19 PM on April 8, 2009 [1 favorite]

we're not even a different species (like dogs and wolves)
You probably mean subspecies; dogs and wolves are the same species.

The boundary for interbreeding may go back a lot farther than 200,000 years. The species barrier is between Homo sapiens and other former members of the genus Homo probably wasn't that strong; we probably could comfortably interbreed with Neandertals and some of the other H. sapiens subspecies, but also with other members of the genus. So, if you really want to get creeped out, consider whether getting it on with a Homo erectus could result in children. There's supposedly evidence against genes from other Homo species or subspecies migrating into the surviving human population, but there's also evidence that pubic lice were originally a H. erectus parasite before 'jumping species'.
posted by monocyte at 1:30 PM on April 8, 2009

You'd probably be considerably taller than most B.C.E. women. Like, way taller than the height differential between you and 99% of contemporary women (right, scientists? I'm guessing here).

Well its been a long time since my paleoanthropology classes (and I presume you were being a bit facetious), but I dont think there would be a huge (pardon the pun) difference. Humans are taller and more robust than we were even a few hundred years ago, but as far as procreation goes, that wouldn't be any sort of obstacle, any more than it was between my 5' tall Mom and my 6'5" Dad. In fact, an average healthy male dropped back a couple thousand years would probably be seen as an ideal mate/hook-up, if only for his relatively splendid dental hygiene. Helen of Troy may have had a pretty face, but she probably was missing a half dozen teeth and what she had made Austin Powers look good.
posted by elendil71 at 1:50 PM on April 8, 2009 [1 favorite]

First of all, the Sumerians were like 6000 years ago, not 15 BC.

I think that the biggest obstacles would be cultural. Are the signals that we give to attract and arouse our mate the same as those which were used 5000 and 10,000 years ago? Which sex acts were normal and which were abnormal back then? Did they have oral sex? We give lots of meaning to somewhat arbitrary things, like body hair, posture, and odor. Our sexual acts are pretty well choreographed. I think she might be creeped out by your crazy futuristic ways, and verse-visa.
posted by goethean at 2:23 PM on April 8, 2009

10^20 grandma? Don't think that's going to work.

Human generations occur say 3 every 100 years. So you'd need to go back 3*10^21 years to find this ancestor.

Good luck; Earth has only been around about 5 billion years, that's about 5*10^9; reasonable definitions for the age of the universe come out around 10^10 years.

Of course I'm slightly lying here, because your ancestors would probably have shorter lifespans as you go back further in time. But if you're interested in ancestors you could possibly reproduce with, let's go with the hominids. That gives you about 5*10^6 years.

So I guess that means you might have a chance with your 10^4 great grandma, but not much farther than that.
posted by nat at 2:47 PM on April 8, 2009

Two things:

1) A couple of hundred years ago, this stuff happened, alot. Those horny conquistadors were shacking up with females who had been more or less genetically separated from them for thousands of years. Lots of people died from diseases (including sexually transmitted ones), but millions of people exist today to attest to the fact that thousands of years of separation make no difference whatsoever. However, I think you would have to go the North Sentinel Island to find any people who still had that level of genetic distance from you.

2) When you meet that cute Sumerian, just say, 'LUGAL ama a-ba-la-as, i-bi kig-ama tes-ub!', and she'll be totally hot for you. Though if you end up in 15 BCE, watch out, as the only people who understood Sumerian by that time were priests and librarians...and I don't think librarians were cute back then.
posted by Sova at 3:18 PM on April 8, 2009 [3 favorites]

Woa!

Messing with history like that could really screw you up! I mean, a generation or two is risky enough but 2000 years? Didn't you get anything from Back To The Future?
posted by BadMiker at 3:49 PM on April 8, 2009

Those smaller people and short lifespans were a product of agriculture. Hunter/gatherers were as tall as modern people (and probably healthier as they were eating the diet we evolved for).

I think hunter/gatherers would have good teeth as well, as their diet was low in sugars and starches.

But yeah, you'll probably kill them with your filthy modern diseases.
posted by zompist at 4:13 PM on April 8, 2009

I'm really not sure why I keep thinking about it, but I do.

Could this be the reason?
posted by Flying Saucer at 5:54 PM on April 8, 2009

I was looking at the genetic variance of E. coli a while back. E. coli strains K12 (which has become the biggy in the BioTech world) and O157 (the one cows and deer have no issue with but which is pathogenic to you and I) only have about 75% DNA in common. That's what you and I have in common with tube worms.

Then I did a little math. In terms of generations, all of recorded history is equivalent to about 1 week of E. coli doublings. 10,000 years ago is nothing.
posted by Kid Charlemagne at 10:06 PM on April 8, 2009

I think hunter/gatherers would have good teeth as well, as their diet was low in sugars and starches.

Ok, bit of a derail but to follow up: You are correct in principle, but I've seen plenty of skulls from prehistoric man and a lot of them had pretty nasty looking abcesses in their maxilla and mandibular bones, due to infected teeth. Hard to say what actually caused their death, but infections like that can easily prove fatal, even today with modern medicine. Case in point from recent news.

/End derail.
posted by elendil71 at 11:08 PM on April 8, 2009

/re-derail
I read/saw somewhere that pre-refined sugar folks had better teeth, longer. I guess if you broke a tooth it would get infected, but cavities?
posted by kristymcj at 11:44 PM on April 8, 2009

Teeth do seem to have had a pretty rough time in pre-history. The typical diet probably included a fair bit of accidental grit; due to milling methods, and just generally being a bit closer to nature. Teeth were also often used as a handy vice, for example; in the neolithic, one technique for flint knapping involved holding the flint with your teeth and smacking it with another stone. I'd guess that sugar damage would be the least of your concerns. There could be any number of reasons why you'd damage a tooth.

So your pretty little Sumerian would probably have a bit of a crooked smile and bad breath. She'd also have quite a pungent aroma to our modern noses.

I'm dont know much about Sumeria, but I'd suspect that you would be the only person who fancied her though. To the other Sumerians she'd probably be way too skinny (our modern obsession with thinness is just weird considered historically) and probably way too old (everyone else would be married post puberty).

Whether she'd find you attractive, or whether you'd even be allowed to speak is another matter. If you are thinking of this, I'd suggest a beard .
posted by BadMiker at 1:50 AM on April 9, 2009

The wikipedia entry for the Grandfather Paradox includes relevant if a touch tangential theories.
posted by gbinal at 2:27 PM on April 9, 2009