Could humans - primitive ones, not modern civilized ones - have survived the K/T extinction event ?

Primate evolution happened pretty much well after the dinosaurs died, but let’s say that there were large primates or hominids alive at the time. Would they have been amongst the extinct ?

Since this is speculative, let’s move it to IMHO.

General Questions Moderator

I would say probably not, since no land animals of any significant size survived the event. For millions of years after the end-Cretaceous event the largest animal on land was not much bigger than a small dog. Primitive humans would have been too large to survive the conditions. They couldn’t have built adequate shelter to shield them from the effects of the asteroid impact or its aftermath, and they couldn’t have found adequate food.

Some large freshwater animals like crocodilians survived. So did cold-blooded land animals like snakes, turtles, and lizards. Small mammals, maybe up to rat size, survived, and smaller birds. But that’s pretty much it for land vertebrates.

That’s the first thing that came to my mind, too. Primates aren’t anything special in that regard.

With enough warning, I would imagine we could construct enough underground facilities and stockpile stores for some remnant to survive, but with no warning it would be awfully difficult.

I think that would be ruled out by the “not civilized ones” clause in the thread title.

We certainly could have, if we had known it was coming. All that’s needed to survive a KT-like event is the ability to store up several years’ worth of food, and we’ve been able to do that for a long time.

The trick, of course, is in the “know it’s coming” part. What if you don’t conveniently have a fellow in a colorful coat to tell the chief that seven years of famine are coming? I think our best hope is that there would be a lot of tribes, with a lot of tribal shamans telling their chiefs all sorts of things about the future, and a few of them are bound to be right just by luck.

And you know this, how?

I believe most land species died due to a breakdown of the food chain.If there were primates that lived underground and that had a food source that wasn’t affected by the meteor then it is possible IMO, but I don’t know how realistic that would be.

I"ve heard that debris re-entering the atmosphere from the meteor raised the global air temperature, and caused many life forms to just die of heat exhaustion pretty rapidly. Is that an agreed upon theory or is that a more controversial theory of the die off from a meteor event?

As has been mentioned, high (or low) temperatures, acid rain, and other atmospheric conditions could have made physical survival impossible for any large animals immediately after the event. Small mammals, especially ones that can hibernate, could remain in a sheltered burrow for a long time without emerging. Humans wouldn’t have that option.

We probably didn’t have the ability to store several years’ worth of food before the development of agriculture and the invention of pottery. Dried meat, berries, etc won’t keep indefinitely, even if well stored. Also, rodents and insects (which would still be around, and very hungry after the event) will get in unless you have something as sturdy as a pot to keep them out.

Even setting aside that this would require industrial technology, the aftereffects of the Cretaceous-Paleogene (K-Pg) impact event and subsequent mass extinction of more than 75% of all megafauna lasted for decades or perhaps even centuries. With current technology, we might be able to sustain a replacement-sized population of humans for a couple of decades underground with extraordinary effort; beyond that the resource and energy requirements are well beyond any practical effort. The notion of being able to keep an essentially closed cycle environment operating for centuries, especially without sunlight and the hydrological and agricultural cycles it powers, is beyond plausibility.


In fact, it is probably those scavengers, capable of flexibly adapting to new conditions, breeding rapidly, and being sustained on meager resources, which will be the ultimate successors, while the apex consumers that are humanity who breed on long cycles and require an enormous amount of resources per unit wuld be one of the first species to go extinct. Being able to think is a great tool to have in the toolbox, but only when you have resources to turn those thoughts into tools.


Oops – somehow I read it as reversed.

For modern humans, Neal Stephenson thinks that with a couple years warning, humans could build an underground civilization that could survive for a couple millennia. Of course, it is a work of fiction, but maybe… Read Seveneves.

Maybe a seafood based society. But primitive man, no way.

What would power this underground civilization?


I think it also depends upon how well dispersed the species is because any calamity will hurt some areas more than others and their might indeed be some areas hardly affected at all. Or maybe a calamity damages one region while it improves another. For example a polar region might suddenly grow warm. Antarctica was once a tropical jungle.

Then its kind of a luck of the draw of just happening to be living in just the right island, mountaintop, or corner of the world when something major hits.

Now if an early species lived in just one area, say central Africa. Then if that region is hit hard no they wont survive.

Isnt this why horses and camels died off in North America while their cousins in other areas survived?

Humans are very adaptable, and we have already survived several really big bangs: Toba and Yellowstone to name but two.

We know that early humans (including Neanderthals) ate shellfish, so any such humans would easily survive, assuming they survived the initial impact. Beyond that, humans are very wide-spread. It would only take one sheltered valley for the humanity to survive.

That’s why I specified non-civilized, I want to know how we compare just physically to the other life forms in this situation.

There’s no way we’d have made it, IMO. We’re too big and needy.

And assuming we were still in Africa, we’d have been closer to the immediate blast effects than in the present day.

That’s something I tried to look up on the interweb, but couldn’t find any sort of chart saying “animals bigger than this didn’t survive.”.

Some large animals made it, but they had things in their favour like water cover or burrows like you say. Caves would maybe be adequate shelter for initial heat shock, but you emerge into a very hostile environment.