Suppose I fire up my time machine, which isn’t in anything as cool as a DeLorean. (It’s a Kia Forte.) I go back to the earlier years of homo sapiens - let’s say about 150,000 years ago, to when we were definitely, well, homo sapiens. I find a baby who has been separated from its parents, perhaps because they were eaten by a large animal, and bring it back and raise the baby.
Will this baby seem entirely indistinguishable from modern humans? What differences might there be? Of course it might not look like me but I can just come up with a plausible-sounding adoption story. I’ll work out some way of getting paperwork establishing the child’s identity so don’t worry about that, let’s just talk physiology and brains. Let’s assume the baby is very young (a few months) and was well cared for before the lion ate its parents and I rescued it. The baby, not the lion.
If you’re talking about a baby who’s still at nursing age, meaning they’ve had roughly the same nutrition as a modern baby, you’ll probably see someone who grows up to be shorter, perhaps with a more stocky build. Intellectually there shouldn’t be much of a difference, and the rest depends on socilization and modern medicine.
That parts concerns me a little. Obviously there are vaccinations, but it crossed by mind that we may just have inherently tougher, faster-to-adapt immune systems now, millennia after animal husbandry started.
Any real evidence for that? I’m pretty sure early Homo Sap produced the same types of general antibodies (IgE, IgA, IgG, IgM) that we do in response to antigen exposure, and I expect they would do so also in response to modern vaccines.
If the baby didn’t seem indistinguishable from today’s children, there’s something wrong with the designation homo sapiens.
Health may be a concern, but with eight billion people alive today (or very soon) I’ll bet any amount of money that the child with be within the spread of modern healthiness.
You made an admirable attempt to avoid the butterfly effect, but you’ll still have caused major waves. Another lion from the same pride would have gotten an easy meal when it found that kid in the original timeline, but instead it went hungry that night, causing a cascade of changes. You’ll have a hard time explaining this infant when you come back to a world where all humans except you and the kid have forked tongues, and donuts regularly fall from the sky.
In the Ray Bradbury story A Sound of Thunder, from which that Simpsons Treehouse of Horrors segment is parodied, the change that happens due to messing with the past is that a fascist Presidential candidate who lost in the original modern timeline (much to the relief of sensible people), has been elected president when the time travelers return to the present, and the general tone of society is more angry and unpleasant.
Hmmm… I think the OP may be talking more than hypotheticals here. They do get pretty specific. Kia Forte? @RickJay, are you responsible for…ah, never mind, couldn’t be.
To answer the OP, I agree with others that a Homo Sapiens baby in good health brought to the present and raised in modern conditions would be little or no different in appearance and intellect than any other modern human. He might even go into the law profession…
In the Language Instinct, by Steven Pinker (which I read a long time ago, so I may have this wrong), he seems to find it unbelievable that modern humans were were around for 100,000 years and did nothing. That is, anatomically modern humans were around for 200,000 years, but nothing happened until 100,000 years ago.
His claim, from my memory, was that the last mutation needed for language showed up and spread rapidly through the population (since it’s such an advantage), and that it was only about 100,000 years ago that our language instinct was fully formed.
So, if my memory is right about his claims and he’s right about them, maybe some speech difficulties?
What about the opposite - the possibility of the baby bringing an unknown-to-us pathogen to modern times? What if you unleashed the next pandemic?
If we assume free from unknown disease, then yeah, likely to grow-up normally. I do wonder about language capacity, tho. When did that come on the scene in human history?
There is some evidence of an increase in cognitive ability around 50,000 - 75,000 years ago, in the form of abstract art, burials, and more elaborate stone tools. This might be linked to the rise of language, a genetic change, or it might not have happened at all.
Would digestion be a problem? Our modern diets are far more complex than what the kid’s parents ate. I don’t know how much of our gut chemistry is inherited and how much is environmental, but either way I suspect the kid might not be ready for mac & cheese.
Not sure at all. You’re probably right about them eating more species than we do, but we eat stuff from all over the planet, not to mention man-made ingredients.
And all that said, I’m also not sure it would make any difference. Maybe Baby Jay’s tummy would be just fine with anything from the local Kroger.
Pretty sure I read on here somewhere that adult lactose digestion is a new mutation since herding. So, like many contemporary humans, the baby would be lactose intolerant. The mac & cheese might be a problem.
It is an open question if the advances in art, stone tools, etc. between 50k-100k years ago is due to genetic changes or cultural ones. Things like language use don’t really show up in the fossil record.
Adult lactose intolerance is still the norm on the planet today. However, we’re talking about a baby. Congenital lactose intolerance worldwide is lower than 1 in 100,000 births. Babies have to be able to tolerant lactose because they’re designed to drink mother’s milk.
Gluten tolerance might be more of a problem, because gluten was not standard in diets 150,000 years ago. But that wouldn’t be a known issue for a baby until solid foods were introduced.
Huge numbers of people worldwide have intolerances or allergies to foods today. Only in rare cases are these discovered in young babies still on liquid foods. When they are discovered, at any age, they are hopefully diagnosed and appropriate substitutes found. Hard to imagine a doctor finding a child with a known and broadly prevalent food disorder and exclaiming A TIME TRAVELER!
