CELL PRESS
Of the six or more different species of early humans, all belonging to the genus Homo, only we Homo sapiens have managed to survive. Now, a study reported in the journal One Earth on October 15 combining climate modeling and the fossil record in search of clues to what led to all those earlier extinctions of our ancient ancestors suggests that climate change–the inability to adapt to either warming or cooling temperatures–likely played a major role in sealing their fate.
“Our findings show that despite technological innovations including the use of fire and refined stone tools, the formation of complex social networks, and–in the case of Neanderthals–even the production of glued spear points, fitted clothes, and a good amount of cultural and genetic exchange with Homo sapiens, past Homo species could not survive intense climate change,” says Pasquale Raia of Università di Napoli Federico II in Napoli, Italy. “They tried hard; they made for the warmest places in reach as the climate got cold, but at the end of the day, that wasn’t enough.”
To shed light on past extinctions of Homo species including H. habilis, H. ergaster, H. erectus, H. heidelbergensis, H. neanderthalensis, and H. sapiens, the researchers relied on a high-resolution past climate emulator, which provides temperature, rainfall, and other data over the last 5 million years. They also looked to an extensive fossil database spanning more than 2,750 archaeological records to model the evolution of Homo species’ climatic niche over time. The goal was to understand the climate preferences of those early humans and how they reacted to changes in climate.
Their studies offer robust evidence that three Homo species–H. erectus, H. heidelbergensis, and H. neanderthalensis–lost a significant portion of their climatic niche just before going extinct. They report that this reduction coincided with sharp, unfavorable changes in the global climate. In the case of Neanderthals, things were likely made even worse by competition with H. sapiens.
“We were surprised by the regularity of the effect of climate change,” Raia says. “It was crystal clear, for the extinct species and for them only, that climatic conditions were just too extreme just before extinction and only in that particular moment.”
Raia notes that there is uncertainty in paleoclimatic reconstruction, the identification of fossil remains at the level of species, and the aging of fossil sites. But, he says, the main insights “hold true under all assumptions.” The findings may serve as a kind of warning to humans today as we face unprecedented changes in the climate, Raia says.
“It is worrisome to discover that our ancestors, which were no less impressive in terms of mental power as compared to any other species on Earth, could not resist climate change,” he said. “And we found that just when our own species is sawing the branch we’re sitting on by causing climate change. I personally take this as a thunderous warning message. Climate change made Homo vulnerable and hapless in the past, and this may just be happening again.”
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This work was supported by MCTIC/CNPq/FAPEG.
One Earth, Raia et al.: “Past extinctions of Homo species coincided with increased vulnerability to climatic change” https://www.cell.com/one-earth/fulltext/S2590-3322(20)30476-0
One Earth (@OneEarth_CP), published by Cell Press, is a monthly journal that features papers from the fields of natural, social, and applied sciences. One Earth is the home for high-quality research that seeks to understand and address today’s environmental grand challenges, publishing across the spectrum of environmental change and sustainability science. Visit http://www.cell.com/one-earth. To receive Cell Press media alerts, contact press@cell.com.
All you need to know about this article and the journal One Earth is right here.
Lewis Collins – Editor-in-Chief
While undergraduate and master’s degrees in Earth science (Cardiff University), and Climate Change (University of East Anglia) nurtured this interest, it was doctoral (British Antarctic Survey) and post-doctoral (Université Pierre et Marie Curie) research on Antarctica that centered his focus on environmental change.
Humm, where have I heard about the University of East Anglia before?
Early humans were modeled into depression and death by others. It worked!
From the above article: “The goal was to understand the climate preferences of those early humans and how they reacted to changes in climate.”
OK, I’ll grab the bull (double entendre) by the horns and give some basic understanding to Pasquale Raia and the other authors of the the above One Earth article vis-a-via this specific goal.
Early humans undoubtedly preferred a climate that:
— provided minimal need for shelter and clothing, being comfortably warm at night and comfortably cool during the day, both independent of the seasons during the year
— provided sufficient rainfall for convenient, nearby sources of water and for growing both plant and animal food sources without also causing flooding
— was reasonable stable over several generations (say, 100 years).
And early humans undoubtedly reacted to changes in climate by:
— changing their clothing and shelter, and/or
— expanding or contracting the selection of food types, and/or
— digging deeper wells (in the case of drought),
— increasing their use of fire (in the case of increased cold), or
— simply migrating from a less-hospitable climate to a more-hospitable climate.
No charge, Mr. Raia, if you want to add these points in an erratum/revision to the above One Earth report to show that you indeed met your identified goal.
“they made for the warmest places in reach as the climate got cold, but at the end of the day, that wasn’t enough.”
So it was the COLD that got them…..
Thank goodness the planet decided to warm up a little bit since the LIA, rather than going the other way.
Humans are still evolving. I read a story where it was said that young humans have an arterry in the arm that is replaced by two other arteries as a person grows, and it said that something like 30 years ago, about 18 percent of humans would retain the original artery, instead of it disappering, and today they estimate that about 30 percent of humans are retaining this artery.
I thought that was pretty interesting.
I wonder how humans will evolve when they leave the Earth enviroment and move into the solar system.
I think the climate change we need to worry about here on Earth is a change to a colder world. Warmer, we can handle.
Instead of 30 years ago, that should read 230 years ago. So the claim is the extra artery was in 18 percent of people 230 years ago and is in 30 percent of people today.
What happens whennyou run this “high resolution climate emulator” forward?
H.G. Wells explored that question, at length.
Max P
Jean,
In reality, the User’s Manual for that climate emulator states the following on Page 1:
************** WARNING ****************
Do NOT attempt to run your MCTIC/CNPq/FAPEG Climate Emulator™ in “forward mode”. It has not been multi-parameter curve-fit to the future because future climate data is not yet available. It will yield erroneous and irrelevant results in the “forward mode”, and your warranty will be voided by doing such.
Please restrict all use of the Climate Emulator™ to “backward mode” (also know as “hindcasting”) since the developers at MCTIC/CNPq/FAPEG, Inc. invested considerable effort to obtain an optimum multi-parameter curve-for to all available paleoclimatology that we judged suitable for our purpose.
***************************************
I’m wondering how you validate the accuracy of a model forecast over 5 million years into the past.
I lament the ongoing dumbness of academia. All I can conclude is that we let too many people become academics, who then need to publish on increasingly stupid topics.
“I’m wondering how you validate the accuracy of a model forecast over 5 million years into the past.”
It’s actually very simple: you create and use another model to do so.
This technique has prove to be very beneficial in “climate science” over the last 20 or so years.
“early human species to extinction” I wonder if inter breeding had anything to do with their extinctions.
Para 2, it was the cold that wiped out the other homo species, NOT WARMING BUT FREEZING KILLED THEM. Cold kills far more people than any warming even today.
Oh dear, did they have gas guzzling SUVs and coal fired power plants? did they not put in enough sola panels? we need to know.
what happened when the homo sapien met the homo neanderthalis? Some say the killed them. Some say the f***ed them. Knowing humans, I think they did both. However, the fact that we all have the adam which can only be passed from father to child suggest that they only bred with the females and probably killed the males which is what you would expect from both savage and modern man.
Wow, researchers looking for a climate change nexus, found a climate change nexus. And they did it using a model. What a surprise.
We should learn from our past, driving those high emitting CO2 Flintstone cars caused the demise of mankind. Here we go again!, driving cars using fossil fuels and releasing all that co2 that has been sequestered since last ice age. Eventually if we keep this up the atmosphere may return to its’ former co2 levels. Gnashing of teeth and handwringing!
Glaciation kills people. Who’d a thunk it ?
The weasel-wording of the release leads me to doubt that any hominid species in the model became extinct from warming.
Can anyone interpret the model to explain which species in what location were harmed by what geologists call ‘global climactic optimums’?
And if there are any such cases, is it in any way an analogy to the circumstances of an agricultural, global, technological species?
These hominids managed to survive several glacial/interglacial cycles, but then climate killed them all off about 40-50 thousand years ago. That this was just when Homo sapiens showed up in their respective habitat was of course purely accidental.
“even worse” “hold true under all assumptions.” “unprecedented ”
These three phrases signify there are problems, not with the subject, but with the research. The other clue is to find the statement “It was worse than we thought.”