Normally we dismiss such warnings as the fevered dreams of overheated brains. Overheating from internal conceptual causes, we mean. But here’s some solid science about climate change bringing humans to the brink of extinction. Please do not panic. It happened in One Million B.C. or thereabouts, when absent malign human influence the dang climate suddenly did something unprecedented, weird and dangerous. Can it do that?

Well, yes. As anyone familiar with its history knows. And before we get into the details, when we say solid science we want to insert a disclaimer about paleoanthropology. Specifically Bill Bryson’s point that for all the pontificating and sensationalism about the human past, long past, if you took all the actual fossils we possess and weren’t worried about proper organization you could fit them into the bed of a large pickup truck. Indeed, in a rare non-climate story Scientific American recently wrote that a new study of an actual cranium:

“which is at least 146,000 years old, ends a decade and a half of speculation about the Denisovans’ appearance. This had remained a mystery since scientists identified them from unique DNA taken from a finger bone found in a Siberian cave in 2010.”

What it did not say, but an email from New Scientist did mention, is that the finger bone in question was, along with a jaw bone, all we had on which to base that speculation.

That said, on to our near-extinction. The apparently solid evidence has to do with DNA from modern humans, over 3,000 of them, both African and non-African, which indicates that our remarkable lack of genetic diversity including our total of 23 chromosomes not the 24 of the other great apes due to a fusion event around that time, is due to our having a “genetic bottleneck” where possibly as few as 1,280 reproductive members of our precursor species, which the article fails to specify, clung to a perilous existence before rebounding and giving the world fast food and memes.

What dreadful scorching heat put us this close to expiring? Um uh well see they don’t know, solid science being less solid than it seems. Indeed how they know there were once 100,000 of Homo erectus or whatever it was, then just 1,280, is not clear since:

“The scarcity of fossils from this period makes it difficult to directly observe the effects of these changes, but genetic data offers a powerful tool to trace their impact.”

No error bars for you. But here’s what they stammer out on the cause:

“The transition into the middle Pleistocene, which saw the Earth cool significantly, may have played a crucial role. Prolonged cold periods and the onset of glaciation, accompanied by severe droughts, likely led to widespread famine and scarcity of resources. These harsh conditions could have driven humans into smaller, isolated groups, competing for survival in increasingly challenging environments.”

Nooooo! Not cold. Cold is good. We want cold. Make it colder. Nassssty yellow face go away. Cold means fewer hurricanes, floods, droughts and crop failures, right? Right guys?

Um no. Despite claims that heat kills more people than cold, the reverse remains true even today and certainly during a glaciation of the sort that have dominated the Pleistocene, one of which was raging a million years ago. So beware of maniacs trying to find ways to get the Earth to cool once again, supposedly to stop at whatever blessed point is the ideal refreshing natural one though they can’t say what it is or how they know. Because cold kills plants, it kills animals, and it very nearly killed us.

As the story confesses:

“The study also suggests that humanity’s recovery from this near-extinction event was likely due to a more hospitable climate around 813,000 years ago. As conditions improved and early humans mastered the use of fire, their chances of survival increased.”

So the story even accidentally includes that having affordable, reliable energy is vital to human flourishing, along with blessed warmth. And it is not overheating but overcooling that menaces us body and mind.