Climate changed the size of our bodies and, to some extent, our brains

UNIVERSITY OF CAMBRIDGE

Research News

IMAGE
IMAGE: SKULLS: – LEFT: AMUD 1, NEANDERTHAL, 55.000 YEARS AGO, ~1750 CM³ – MIDDLE: CRO MAGNON, HOMO SAPIENS, 32.000 YEARS AGO, ~1570 CM³ – RIGHT: ATAPUERCA 5, MIDDLE PLEISTOCENE HOMO, 430.000 YEARS AGO,… view more CREDIT: MANUEL WILL
  • The average body size of humans has fluctuated significantly over the last million years and is strongly linked to temperature.
  • Colder, harsher climates drove the evolution of larger body sizes, while warmer climates led to smaller bodies.Brain size also changed dramatically but did not evolve in tandem with body size.

An interdisciplinary team of researchers, led by the Universities of Cambridge and Tübingen, has gathered measurements of body and brain size for over 300 fossils from the genus Homo found across the globe. By combining this data with a reconstruction of the world’s regional climates over the last million years, they have pinpointed the specific climate experienced by each fossil when it was a living human.

The study reveals that the average body size of humans has fluctuated significantly over the last million years, with larger bodies evolving in colder regions. Larger size is thought to act as a buffer against colder temperatures: less heat is lost from a body when its mass is large relative to its surface area. The results are published today in the journal Nature Communications.

Our species, Homo sapiens, emerged around 300,000 years ago in Africa. The genus Homo has existed for much longer, and includes the Neanderthals and other extinct, related species such as Homo habilis and Homo erectus.

A defining trait of the evolution of our genus is a trend of increasing body and brain size; compared to earlier species such as Homo habilis, we are 50% heavier and our brains are three times larger. But the drivers behind such changes remain highly debated.

“Our study indicates that climate – particularly temperature – has been the main driver of changes in body size for the past million years,” said Professor Andrea Manica, a researcher in the University of Cambridge’s Department of Zoology who led the study.

He added: “We can see from people living today that those in warmer climates tend to be smaller, and those living in colder climates tend to be bigger. We now know that the same climatic influences have been at work for the last million years.”

The researchers also looked at the effect of environmental factors on brain size in the genus Homo, but correlations were generally weak. Brain size tended to be larger when Homo was living in habitats with less vegetation, like open steppes and grasslands, but also in ecologically more stable areas. In combination with archaeological data, the results suggest that people living in these habitats hunted large animals as food – a complex task that might have driven the evolution of larger brains.

“We found that different factors determine brain size and body size – they’re not under the same evolutionary pressures. The environment has a much greater influence on our body size than our brain size,” said Dr Manuel Will at the University of Tubingen, Germany, first author of the study.

He added: “There is an indirect environmental influence on brain size in more stable and open areas: the amount of nutrients gained from the environment had to be sufficient to allow for the maintenance and growth of our large and particularly energy-demanding brains.”

This research also suggests that non-environmental factors were more important for driving larger brains than climate, prime candidates being the added cognitive challenges of increasingly complex social lives, more diverse diets, and more sophisticated technology.

The researchers say there is good evidence that human body and brain size continue to evolve. The human physique is still adapting to different temperatures, with on average larger-bodied people living in colder climates today. Brain size in our species appears to have been shrinking since the beginning of the Holocene (around 11,650 years ago). The increasing dependence on technology, such as an outsourcing of complex tasks to computers, may cause brains to shrink even more over the next few thousand years.

“It’s fun to speculate about what will happen to body and brain sizes in the future, but we should be careful not to extrapolate too much based on the last million years because so many factors can change,” said Manica.

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Jeroen B.
July 9, 2021 10:04 am

I could postulate that in the case of some adherents of the CAGW religion, brain size has dwindled to nothing already; unfortunately this isn’t preventing them from spreading their gospel or reproduction. /humor

John Shotsky
Reply to  Jeroen B.
July 9, 2021 11:00 am

For the rest of us, our brains are exploding!!!

Greg
Reply to  Jeroen B.
July 9, 2021 1:12 pm

Rising CO2 definitely seems to correlate strongly with a decline in mental ability.

I know correlation does not prove causation but it’s pretty persuasive all the same.

Reply to  Greg
July 9, 2021 2:23 pm

Children wearing masks have to endure 14,000 ppm CO2

Chaswarnertoo
Reply to  Krishna Gans
July 9, 2021 11:46 pm

More than submariners, limited to 10,000 ppm.

Philo
Reply to  Krishna Gans
July 10, 2021 8:56 am

I’ve seen a couple reports of as high as 20,000 ppm CO2 in some schools.
The teacher was talking about global warming.

Gunga Din
Reply to  Jeroen B.
July 10, 2021 4:33 pm

But the dwindling brain size has produced more airheads and echo chambers!

TheFinalNail
July 9, 2021 10:12 am

“Brain size in our species appears to have been shrinking since the beginning of the Holocene (around 11,650 years ago)….”

Must have been some interesting philosophical discussions around the campfire back then.

Curious George
Reply to  TheFinalNail
July 9, 2021 10:55 am

We are being domesticated. Brains in domestic animals are some 20% smaller than their wild cousins. For comparison, Neanderthal brains were about 25% larger than Delaware brains.

Last edited 22 days ago by Curious George
Rich Davis
Reply to  Curious George
July 9, 2021 11:46 am

Umm, division by zero error, if you refer to the Delawarean that I am thinking of
#BlankLooksMatter

Greg
Reply to  Rich Davis
July 9, 2021 1:14 pm

Yes, Delaware brains seems an odd point of reference.

Joao Martins
Reply to  TheFinalNail
July 9, 2021 1:34 pm

Brain is another organ for which size does not matter…

Unlike other organs for which size does not matter, what matters is how much it is wrapped inside the skull (that is to say, what matters is its surface area… roughly…).

Last edited 22 days ago by Joao Martins
BCBill
Reply to  Joao Martins
July 9, 2021 4:05 pm

If there was ever an area of research that was subject to more SJW tampering than AGW, it is the study of the relationship between brain size and intelligence. Since women have on average smaller brains than men, we can see clearly that this brain size truism has to go and the junk science supporting that position has flooded the usual sources. However, brain to body mass ratio remains a strong indicator of intelligence wherever the SJWs haven’t yet sunk their evil tentacles. Other factors are also clearly important, but junk science can’t make the truth disappear. https://www.nature.com/articles/s41467-018-04268-8?utm_medium=affiliate&utm_source=commission_junction&utm_campaign=3_nsn6445_deeplink_PID100102460&utm_content=deeplink

Last edited 21 days ago by BCBill
Sara
Reply to  TheFinalNail
July 10, 2021 5:53 am

How might shrinking brain sizes/volumes apply to politicians and their sycophants? 🙂

Sara
Reply to  Sara
July 10, 2021 5:57 am

I will add here that the human brain generally has a 60% fat volume, so take that into account.

Gunga Din
Reply to  Sara
July 10, 2021 4:37 pm

In regards to certain politicians, they want to fill the void with pork.
(If some of that pork fat leaks into their wallets, so much the better.)

TonyG
Reply to  Sara
July 11, 2021 9:04 am

That would suggest that everyone is a fat-head, right?

Tom Halla
July 9, 2021 10:14 am

I would tend to reject basic premise, that small people tend to be associated with warmer areas. While Southeast Asians are rather petite, tropical Africans are not. Neither are all inhabitants of South Asia anywhere near the same size, ranging from rather short to rather tall.

Reply to  Tom Halla
July 9, 2021 10:35 am

Pygmy and Bushmen fit to the cliché.

John Tillman
Reply to  Krishna Gans
July 9, 2021 10:40 am

Khoisan people are subtropical.

But both pygmies and South Sudanese nilotic giants, such as the Dinka and Nuer, are indeed tropical.

John Tillman
Reply to  John Tillman
July 9, 2021 1:11 pm

Although Khoisan people historically ranged into tropical reaches of the Kalahari in northern Namibia and Angola.

stinkerp
Reply to  Krishna Gans
July 9, 2021 1:42 pm

Get them some air conditioners.

H. D. Hoese
Reply to  Tom Halla
July 9, 2021 10:59 am

It’s Bergmann’s Law, now called a rule, has to do with body mass/surface area ratios and heat loss/retention. Size not height.

Rich Davis
Reply to  H. D. Hoese
July 9, 2021 11:53 am

And they infer the mass of people from their fossilized remains how?

Joao Martins
Reply to  H. D. Hoese
July 9, 2021 2:05 pm

Sorry, I did not see this comment of yours when I wrote about Bergmann’s rule.

But, NO! It depends! The get thin, a human can grow in height. It is not only “size”, but “size and shape” that matters for Bergmann’s rule. And so, yes, height matters, but in relation to the shape, thick or thin.

lee
Reply to  Joao Martins
July 9, 2021 7:40 pm

I used to be 6 foot high. Now 5foot 4inches. All those pats on the head I say. My shape as also changed. 😉

DaveW
Reply to  H. D. Hoese
July 9, 2021 8:23 pm

I wouldn’t even call it a ‘rule’, more a cherry-picked pattern that works within some mammalian species if you ignore the exceptions.

To bed B
Reply to  H. D. Hoese
July 10, 2021 7:08 pm

The Eskimo v Polynesian rugby match should be a corner.

Zig Zag Wanderer
Reply to  Tom Halla
July 9, 2021 11:17 am

Exactly. And look at Samoans.

In my experience it’s more to do with diet. Now that several Asian countries are improving their diets and eating more meat, especially when they migrate to Western countries, they tend to become larger.

In Australia, where meat is plentiful, good quality and cheap, this is the only country I’ve lived in where I regularly meet people as tall or taller than myself at 6′ 3″, but I’ve never lived in Africa where it might be more common.

Philo
Reply to  Zig Zag Wanderer
July 10, 2021 9:16 am

Interesting. I worked with a Nigerian family. The dad was native to Nigeria, about 5’6″ and a normal build. The mom was a native Nigerian about 5’9″, quite heavy set. The two boys grew up mostly in the US. One was about 5’11”, and the other 6’3″. They both were skinny, lots of muscle showing, but not bulky.

The Dad was very intelligent, but also very well educated, the wife the same. The boys seemed to be going the same route.

gbaikie
Reply to  Tom Halla
July 9, 2021 12:48 pm

Africa is called the hottest continent. Most of it is in the northern Hemisphere and most is either side of equator. but it’s big continent and has cooler regions.
But what Africa’s average temperature during a glaciation period? I guess somewhere around US average temperature which around the average Northern Hemisphere average land temperature of about 12 C. Southern average land is about 8 C {due to Antarctica which small percentage of global land, but there is less land in the Southern Hemisphere}. Australia
plays large role in bumping it up so not colder than 8 C and Africa large and warm land in Northern Hemisphere bumps northern Hemisphere to 12 C. And global average land is about 10 C. Global ocean average is about 17 C, giving 15 C global average.
So if during glaciation Africa average cools to 12 C [around US current average] then it not place to not have clothes to keep you warm. Or for tropical creature which is human, it’s cold.
Whereas southeast Asia in glaciation period would probably about same temperature as it is
currently- because kept warm by tropical ocean which remains around the same temperature during a glaciation period. During glaciation period, Africa probably remains the warmest continent but India or Australia {neither continents] could be much warmer.

Zig Zag Wanderer
Reply to  gbaikie
July 9, 2021 1:52 pm

India or Australia {neither continents] could be much warmer.

I might object up that. India is a subcontinent, but Australia is pretty much a continent in itself, with a few surrounding islands.

However, I doubt that Australia is as warm as Africa, even taking extreme south Africa into consideration. Less than half is in the tropics.

Last edited 22 days ago by Zig Zag Wanderer
gbaikie
Reply to  Zig Zag Wanderer
July 9, 2021 4:23 pm

yeah, my wrong Australia is counted as continent.
It’s also country and Berkeley Earth gives it’s average temperature as about 22.5 C:
http://berkeleyearth.lbl.gov/regions/australia
{which is cooler than India:
http://berkeleyearth.lbl.gov/regions/india ]
But seems to me both India and Australia should cool less during a glaciation period- as would South America.
I guess one could google when Australia deserts were not deserts.
Hmm:
Expedition co-chief Associate Professor Stephen Gallagher, from the University of Melbourne, said scientists on board the ship had discovered Australia’s deserts were only 1.5 million years old, making them among the world’s youngest.”
https://www.abc.net.au/news/2015-10-01/australian-deserts-young-but-monsoon-is-old-new-study-shows/6821154
Well since Australia is continent then it might be doubtful it’s retain the hottest continent status during a glaciation period and probably could be during thousands of years it is, and in other thousands of years it’s not.

another ian
Reply to  Zig Zag Wanderer
July 9, 2021 6:47 pm

Just be patient and give the BOM a bit more time (/s)

Joao Martins
Reply to  Tom Halla
July 9, 2021 1:59 pm

Yes. I wonder if the original article (which I did not read yet) treats the question rather shallowly as if humans were subject to natural selection like the other living beings; Darwinism a la Readers Digest. The fact is, we (humans) were, and still are, but from long ago there are other (laws), social, that change the game: if a tiger is cold, it may find shelter somewhere to stay quietly burning accumulated fat; humans, when they are cold, put on some more clothes and carry on what they were doing (a simple example to illustrate the point). There is an old law in zoology (Bergmann’s law; or, better: Bergmann’s rule) that state that in warm blood animals their limbs, ears, other apppendages, are shorter and thicker in cold climates, and tend to become thin and long in warmer climates; the same applies to the bulk of the body. In cold blood animals roughly the opposite is observed. Bergmann’s rule just states a consequence of the ratio of the body (or limb) mass to its surface and what that means for losing or acquiring heath: a mammal will spend less energy near the poles to be warm if its body is roundish; and it will be easier to lose heath in the tropics if the limbs, ears, etc., and the whole body, are thin. I guess that this MAY be observed in human fossils; but along with these natural conditions there MUST be a consideration of the social organization and the level of the material culture, the type of food, how regular was the food supply, etc. Food, good or bad nutrition, I think is THE most important factor concerning human growth (and thus human dimensions). There are many statistics of the change in height of the population of many countries during the 20th century. Most obvious after the WWII.

Last edited 22 days ago by Joao Martins
Fran
Reply to  Joao Martins
July 9, 2021 5:20 pm

See my comment above – genes for shorter limbs more in cold climates, longer limbs in warm. Fits nicely.

Fran
Reply to  Tom Halla
July 9, 2021 5:16 pm

Body size is very much affected by the local conditions. For example, Japanese a quite petite, but after 2 generations on American diets, they are much bigger. I seem to recall an analysis of genetic factors that influence limb length (there are dozens of genes) which found that genetic potential for longer limbs was associated with hot climates and short limbs with cold climates. This is of course modern genomes from around the world.

Tom Halla
Reply to  Fran
July 9, 2021 5:36 pm

I grew up in San Jose, California, and my contemporaries of Japanese ancestry were not small (I’m 65). I remember seeing the congregants entering the mostly Japanese Buddhist temple, and extended families were like a stair-step, with the granny a good foot shorter than her granddaughter.

Mark E Shulgasser
Reply to  Tom Halla
July 9, 2021 5:25 pm

And Eskimos are small. I wonder why they think that prehistoric skulls that have survived are a random sample.

DaveW
Reply to  Tom Halla
July 9, 2021 8:20 pm

Yes, Masai and Inuits immediately came to mind. Limb length is probably a better indicator of environmental temperatures than body size per se for humans. This is just more armchair handwaving:

“He added: “We can see from people living today that those in warmer climates tend to be smaller, and those living in colder climates tend to be bigger. We now know that the same climatic influences have been at work for the last million years.”

Pamela Matlack-Klein
Reply to  Tom Halla
July 10, 2021 2:04 am

Fijians are also large people, men and women alike, as were the original Hawaiians. This article is full of nonsense and biased conclusions. They were careful to skirt around the eating of meat as a factor in brain size brushing it off as incidental to hunting success.

Vikings were not all big people either, despite living in cold climates. This sort of blows their cold climate good theory out of the water.

IMO, good nutrition has pretty much always been why people grow larger. People who eat a diet rich in quality protein will grow to their genetically-determined size.

July 9, 2021 10:28 am

Should I believe, Massai live somewhere at the poles ?
Btw, nutrition is an important factor in concern of body size……

Tom Foley
Reply to  Krishna Gans
July 9, 2021 10:37 am

When British convicts were transported to Australia, their children were so much taller they were nicknamed ‘cornstalks’. Australia is quite a bit warmer than the British Isles, so the accepted explanation is better nutrition.

Reply to  Tom Foley
July 9, 2021 1:30 pm

The generations after WW2 was much taller than their parents.

dk_
Reply to  Krishna Gans
July 9, 2021 10:47 am

Krishna,
Exactly. I’ve seen descriptions of Shaka and other Zulu who were said to be taller than their European opponents (mostly German and English, apropos to researchers at Tubingen and Cambridge) so not just the Massai. If one is to do a study of body size over a million years, it would probably be smart not to depend on only 300 fossil remains. Body size is more influenced by nutrition over several generations: not just for humans, but for most mammals.
Too many assumptions and prejudices for this to be called science.

Reply to  dk_
July 9, 2021 10:58 am

Massai are said to have an average size over 1,80m.
I have only 1,76m 😀

Last edited 22 days ago by Krishna Gans
gringojay
Reply to  dk_
July 9, 2021 3:25 pm

Zulus are descended from migrants moving south to where Europeans encountered them. Their distant forefathers were “Abe”Nguni people who lived in Africa’s Great Lakes region; “u”Nguni went south and Zulu-land arose.

The origin of the AbeNguni is not immediately in the African Great Lakes region; they themselves arrived there by coming south. Although they are not descended from Hamites ( like the relatively tall Masai ) I wonder if the AbeNguni might also (like the “paleo”-hamites) be descended from an ancient back-to-Africa migration coming from colder lands.

Please see my earlier comment about 3 threads below which elaborates on Masai. It develops a point about cold and height which relates to the Original Post (O.P.) and specifies an interesting 2017 citation for greater context of my take on O.P.

Tom in Florida
Reply to  Krishna Gans
July 9, 2021 2:36 pm

Specifically, it is protein that is the most important factor in brain and body size. When early humans began to consume meat as the major part of their diet it set in motion the evolution of larger brains and bodies. Vegans take note.

BCBill
Reply to  Tom in Florida
July 9, 2021 4:20 pm

Essential fatty acids found in seafood and other meat are probably more important than protein. Eat your fat!

Pamela Matlack-Klein
Reply to  Tom in Florida
July 10, 2021 2:16 am

Just so. The evidence for this is overwhelming. When children are fed nutritious diets rich in quality protein, they tend to grow taller than their parents. These “researchers” are making a lame argument for a meatless diet and colder world.

Apparently some vegans/vegetarians have taken note of this as well. It is now considered kosher to eat eggs from the chickens one keeps as pets.

Rich Davis
Reply to  Pamela Matlack-Klein
July 10, 2021 12:21 pm

How can I resist?

Chicken make a lousy house pet!

Bill Powers
July 9, 2021 10:50 am

Just another example of Pseudo Intellectual bureaucrats, working on behalf of the Faceless Cultural Elite, forcing the connection of unconnectable dots. There childlike connect the dots puzzles always resemble surrealist drawings.

Rud Istvan
July 9, 2021 10:58 am

I won’t argue the paleoanthropological evidence, but will argue the conclusion. Cold adaptation is simply a higher BMI, not a larger overall body size. That can be seen by comparing two modern hunter gatherer societies: the Maasai in Africa and the Inuit in the Canadian Arctic. I just did the research. Is recent (last decade) data, washing out any ‘civilization’ influences.

For both, women are less tall than men (standard human dimorphism). Following are averages for ~50:50 adult mixes. Note neither group has a weight/fat problem, as they are not sedentary, live mainly outdoors, and lack sugars and other simple carbohydrates. Shortness compared to US may be due to less nutritious diet.
Data are from articles archived at NCBI.NIH via pubmed.

Inuit: avg height 160cm, avg weight 68kg, BMI 26.7
Maasai: avg height 160cm, avg weight 50kg, BMI 19.5

By reference for US adults per CDC (all races): avg height 159cm, avg weight 90kg, BMI 29.1 (>=30 is morbidly obese). No reason for US BMI ‘cold adaptation’ given we all live with indoor winter heating. A pet peeve, as diabetes type 2 and it’s complications result in DIRECT annual US healthcare costs about 1.5x all cancers, per CDC.

Rud Istvan
Reply to  Rud Istvan
July 9, 2021 11:38 am

Correction.US avg height 169cm, not 159. Significantly taller than Inuit and Maasai.

Donna K. Becker
Reply to  Rud Istvan
July 9, 2021 12:30 pm

I thought a BMI of 30 was obese and that morbid obesity began at a BMI of 40.

Rud Istvan
Reply to  Donna K. Becker
July 9, 2021 12:36 pm

Yup. Overweight 25-30, obese 30+, morbidly obese 40+, or 35+ with other symptoms. Just double checked.

KnowNonsense
Reply to  Rud Istvan
July 11, 2021 8:50 am

Rud, watch an international rugby match. You will see 3 morbidly obese men (by BMI indices) knocking the @”&£ out of each other for 80 minutes in the most physically active encounter apart from the boxing ring. BMI is a crude tool.

AlexBerlin
Reply to  Rud Istvan
July 9, 2021 1:03 pm

“[BMI]>=30 is morbidly obese”. A telltale propaganda lie on a par with the infamous “97%” percent that shows you have no interest in reporting the observable truth, namely that life expectancy is HIGHEST in those countries where imaginary weight-related diseases should, if any of your BS were true, have killed off the majority of the population long ago. The current BMI “normal values” make about as much sense as “pre-industrial temperatures”: Just like the purpose of the latter is to trick us into believing that something is wrong with today’s climate and we need painful and invasive intervention to “correct” it, the purpose of quoting “normal” BMIs that correspond to the brink of being undernourished (or slightly beyond) is to frighten a host of healthy but well-fed people into consulting, and thus generating income for, doctors who then diagnose confabulated “diseases” that (of course) need lifelong medical assistance and expensive treatment to “cope” with (e.g. the enourmous costs of “Type 2 Diabetes” treatment that you quote, a name invented to give the illusion that the gradual failing of the digestive functions as a person nears the end of their natural lifespan is a “disease” that can, and should, be treated – usually with the result that other degenerative and end-of-lifespan-related diseases like cancer, arteriosclerosis, and senile dementia have time to develop and generate yet more income for the medical crooks!). Like terrorist “laws” whose only purpose is to turn people into “criminals” to then better suppress them, these dietary “laws” only have the purpose to make people worry about their health to better fleece them (or their healthcare plan) of their money. No different from the orchestrated Corona hystery.

Last edited 22 days ago by AlexBerlin
Reply to  Rud Istvan
July 9, 2021 2:19 pm

I never had a look on my BMI – I see no necessity as I feel well. As long as that doesn’t change…. There will be certainely other reasons than BMI In so far BMI is overrated.

gringojay
Reply to  Rud Istvan
July 9, 2021 2:46 pm

Masai are descended from the “paleo-hamites” that migrated into Africa during a time of the (“upper”) Paleolithic period when a land bridge existed with (south-western) Arabia. The paleo-hamites hunted, fished and foraged for food; their successive lineages are deemed “proto-hamites”.

Hamites expanded into areas of Africa and in some cases the smaller stature Bantus migrated out as a consequence. In other words, tall Masai did not spring up like an anomaly
among short Africans.

As for the Original Post about cold favoring height I want to point out that height affords more total area for skeletal muscle on the human body. Maybe many people think humans rely on shivering to keep body temperature up when it is cold; when actually our skeletal muscles perform “non-shiveing” processes involved in our reaction to cold.

It is the “non-shivering” skeletal muscle importance that I posit contributed to human proclivity for relatively increased stature height in populations adapting to cold climates which preceded recorded history’s settlement we now look at geographically. For example:
if Masai in warm Africa descend from Hamites who came through a south-west Arabia route and the original Paleolithic stock was adapted to desert-like conditions those people had to survive the extreme night time temperature drop that occurs in deserts – better than energy consuming shivering those ancestors dedicated resources to grow longer bones as skeletal muscle scaffolding and survive cold desert nights via “non-shivering” skeletal muscle heat generation.

When we look at the tall Masai (Hamitic) being healthy on their diet one impulse is to consider their diet. What I would say is to consider how their tall stature, that affords them extensive platforms for skeletal muscle, is integral to their health; for example as regards how insulin plays out.

Those interested in theme introduced immediately above can read free full text available on-line of: “Skeletal Muscle Thermogenesis and It’s Role in Whole Body Energy Metabolism”.

Russ R.
Reply to  Rud Istvan
July 10, 2021 10:33 am

I see this more about the ability to store calories for survival during periods of low nutritional intake. Body fat would solve two problems for those in a cold climate. Provide calories during the winter, and provide insulation during the cold.
But carrying body fat requires stronger muscles and stronger bones for an active lifestyle.
This would not require additional height, but it may be a byproduct of stronger bones and greater capacity to carry fat into the winter.
Some people may get more calories in the winter if they hunt animals that become weak and vulnerable to the weather. But I think that would be the exception.
The majority of people would live on less, and continue to live on less, while their crops were maturing and spring rains turn ground into mud.
This is more of a “feast or famine” body mass solution to a seasonal problem, than a heat retention solution to a cold temperatures problem.

MarkW
July 9, 2021 11:29 am

While a large body is going to lose less heat per unit mass, it will still lose more heat over all than a smaller body.

Greg
Reply to  MarkW
July 9, 2021 1:23 pm

But the larger volume of the system will digest more food and generate more heat. So it’s heat created vs heat lost vol/surface r^3/r^2

Small creatures like mice and small birds need to eat almost non stop in winter. Bears sleep.

Last edited 22 days ago by Greg
MarkW
Reply to  Greg
July 9, 2021 2:58 pm

Before a body can ingest more food, that food has to exist in it’s environment.
Aren’t cold climates supposed to be bad for growing food?

Poems of our Climate
Reply to  MarkW
July 9, 2021 3:14 pm

No. Animal-based foods are superior nutrition and animals were aplenty.

MarkW
Reply to  Poems of our Climate
July 9, 2021 6:51 pm

Animal based food still needs to eat plants at some point in the food chain.

BCBill
Reply to  Greg
July 9, 2021 4:43 pm

Small birds are amazingly well insulated and on the coldest days they puff themselves out and move very little. Where possible, small mammals stay warm under the snow and party the winter away.

Mr.
July 9, 2021 11:39 am

Brain mass does not equal sharpness of mind, or “nous”.

Someone with a head the size of a pumpkin like Boris Johnson no doubt has a largish brain.

But Boris isn’t the sharpest pencil in the case.

Reply to  Mr.
July 9, 2021 1:02 pm

Do elephants and whales and gorillas have larger than Boris brains? The N. Korean population versus the S. Korean population shows the importance of nutrition within just a limited no. of generations.
Also, the very beautiful snow leopard has very thick fur but a much smaller cousin in the same area has an even thicker fur….ask Nature?

Last edited 22 days ago by Anti_griff
Reply to  Mr.
July 9, 2021 1:40 pm

Often, the head isn’t more than a hollowware.
Or a stopper for reign, preventing to enter into the body from above by trachea and gullet.

BCBill
Reply to  Krishna Gans
July 9, 2021 4:46 pm

It is the lower neuron density in the pumpkin head that allows it to function more efficiently. See my link somewhere above.

Reply to  BCBill
July 10, 2021 3:09 pm

Joke detector defrect ? 😀

Poems of our Climate
Reply to  Mr.
July 9, 2021 3:15 pm

Average brain size might matter.

Rich Davis
July 9, 2021 11:41 am

How can this not be from YouReekAlot!?

About a half second of thought, and the slightest familiarity with world cultures would immediately set your bs meter dinging madly.

It’s not really worth much discussion, but some of the tallest populations are in east Africa near the equator.

On the other hand, the Inuit in the far north are not noted as giants. Greenland data from 1963: ave male 164 cm and 64 kg (5’4-1/2” and 141 lbs).

Gordon A. Dressler
July 9, 2021 11:44 am

WAIT! WAIT! WAIT!

I this an outright admission that there can be “climate change” with human emissions of CO2?

Who would have thought we’d see the day . . .

Back to the drawings boards, all you AGW/CAGW alarmists!

Editor
July 9, 2021 11:47 am

My goodness — I wish I could twist the arrow of cause around so many different ways using only temperature records and the sizes of skulls and bones.

“The researchers say there is good evidence that human body and brain size continue to evolve. The human physique is still adapting to different temperatures, with on average larger-bodied people living in colder climates today.”

Couldn’t have been any of a million or so other evolutionary factors? Improved diets? Selective breeding? Cultural mate-selection practices?

That’s some type of science.

Most humans don’t actually live in their environments — they live in an artificial version of their environment. Temperature controlled or regulated homes, cars and offices. In the United States, people are subjected to winter temperatures mostly for recreation (some poor souls have to brave winter for their work but only a few hours day).

Don’t any of these researchers live in the Real World?

dk_
Reply to  Kip Hansen
July 9, 2021 1:07 pm

Don’t any of these researchers live in the Real World?

err, modern academics, Kip? I think the question answers itself.

Zig Zag Wanderer
Reply to  Kip Hansen
July 9, 2021 1:58 pm

Kip, next you’ll be claiming that tree rings are affected by other things than temperature! You know that’s pretty close to heresy….

Editor
Reply to  Zig Zag Wanderer
July 9, 2021 3:28 pm

Zig Zag ==> Even I wouldn’t commit such sacrilege! Of course, only specially selected trees have the right rings that give temperature to the tenth of a degree C.

Chaswarnertoo
Reply to  Kip Hansen
July 9, 2021 11:51 pm

Adjustocene rings….

Joao Martins
Reply to  Kip Hansen
July 9, 2021 2:10 pm

So right!

I agree! Totally!

Gunga Din
Reply to  Kip Hansen
July 10, 2021 5:41 pm

“Birds of a feather flock together”.
What people refer to as “race” goes way back to which “birds” of the human race “flocked together” long enough for some traits to have been bred out in different areas.
Mendel’s Law.
Sure, nutrition, etc. can change how tall (or whatever) the offspring can be. But not because a “tall” gene suddenly appeared.
Now society is more prone to accept the mixing of Man’s artificial divisions between the Human race.
Mendel’s Law.

So what was “THE cause” of what they’ve noticed in the fossil record?
I don’t know.
But I do know they don’t know either.
They’ve put forth a hypothesis.

TonyG
Reply to  Kip Hansen
July 11, 2021 9:10 am

Kip,
Same as trees I guess. Has “science” thrown out all other factors leaving temperature as the ONLY factor that affects ANYTHING regarding living organisms?

Editor
Reply to  TonyG
July 11, 2021 4:15 pm

TonyG ==> The enterprise called Science has been degraded by many things — much of it by the relaxing of scientific rules of evidence.

D Clothier
July 9, 2021 12:21 pm

So that’s why the largest dinosaurs lived in the coldest environments, right? Or why elephants, hippos, and giraffes live in the coldest parts of the world?

Myron
July 9, 2021 12:25 pm

Yet it seems nature doesn’t follow this ‘science’. Desert hares have longer bodies and larger ears than Arctic hares.
And I sure haven’t seen the NBA recruit any 7 foot Eskimos to play basketball.

Thomas Gasloli
July 9, 2021 12:39 pm

Another example of why we should consider shutting all the universities down. No education, no science, no fact, just “climate science”, or other woke, BS.

a happy little debunker
July 9, 2021 12:45 pm

If climate shaped our body size and people were larger in colder environs – how do they explain the world’s obesity crisis?

Tom Foley
Reply to  a happy little debunker
July 9, 2021 5:55 pm

You can now eat more food than you need without personally expending any energy to hunt, catch, grow or harvest it. Regardless of what climate you live in.

bill Johnston
Reply to  Tom Foley
July 10, 2021 8:20 am

Which nicely explains the fallacy behind some of the current diet fads. “Eat protean, lots of fat. Eat like our ancestors did.” Except they had to work much harder for their food. More expended energy.

Duane
July 9, 2021 12:53 pm

Well, natural selection does tend to favor those traits like larger bodies that lead to less mortality and greater reproductivity. But at the same time it has to be recognized that when it is colder, overall morbidity and morality for humans (and most species) are much higher than during warmer periods, due to reduced food availability, and the resultant lower disease resistance from constant hunger, and by simply freezing to death.

Also bigger bodies tend to make humans more competitive, physically, in terms of coercion and violence, and so when there is a famine due to cold climate, the big bodies will tend to dominate and rub out the little bodies, take their food, and thus survive better, and reproduce better..

So the end result of these influences is to have, during cold eras, fewer people with larger bodies … so those who don’t obtain sufficient food to develop the larger bodies die more often, before they have a chance to reproduce and nurture their young, both due to environmental factors and due to competitive factors.

Duane
Reply to  Duane
July 9, 2021 12:55 pm

I meant to write “morbidity and mortality” not morality … freudian slip?

Jim Gorman
Reply to  Duane
July 9, 2021 4:27 pm

This was exactly my thought when I read the information. The researchers must have had some confirmation bias to reach this conclusion. Humans are pretty well known for being warlike, where the larger and more powerful reap the spoils. Hard to believe that this didn’t have a large effect on the resulting sizes. I’ll bet there are sociological anthropologists that have a few things to say about this.

Greg
July 9, 2021 1:09 pm

The study reveals that the average body size of humans has fluctuated significantly over the last million years, with larger bodies evolving in colder regions. Larger size is thought to act as a buffer against colder temperatures: less heat is lost from a body when its mass is large relative to its surface area.

A common sense but rather trivial line of argument. So why aren’t eskimoes the biggest modern humans and the generally powerful sub-saharan africans are some of the most physically powerful and not all pygmies ??

Oh dear, I guess that didn’t work out too well.

The researchers say there is good evidence that human body and brain size continue to evolve.

No shit Sherlock !

Smart Rock
July 9, 2021 1:23 pm

I seem to remember learning, a long time ago, that brain size is not a determinant of intelligence or memory. It was said that the surface area of the brain is what matters. Surface area would be a function of brain size and the degree of involution.

I suspect that neither is really important, compared with how much of our brains we use, and how we use the parts that we do use.

Zig Zag Wanderer
Reply to  Smart Rock
July 9, 2021 2:01 pm

Definitely. When you look at how intelligent some birds can be, and compare them to the average Climate Scientologists, you can see how brain size is completely irrelevant!

Reply to  Zig Zag Wanderer
July 9, 2021 2:29 pm

Conclusion: make birds working as climate scientists 😀

MarkW
Reply to  Krishna Gans
July 9, 2021 3:01 pm

and make climate scientists fly

Russ R.
Reply to  Smart Rock
July 10, 2021 10:54 am

There is a specific correlation between the ratio of brain size to body mass that indicates animals with larger ratios have greater cognitive ability.
Some examples would be dolphins, chimpanzees, crows and similar birds, and parrots.
These animals show specific learning ability not found in other animals that seem “smart”, but are limited to mimicking actions that are rewarded (dogs, horses).
Higher coginitive ability is shown by planning, problem solving, tool usage, and analyzing results and changing behavior based on those results.

This means climate scientists are dumber than magpies.

Waza
July 9, 2021 2:25 pm

In terms of heat/cold adaptation it could be dominated by chemical rather than physical. Example Australian aborigines are able to vary their hormone levels such as thyroxine.

Additionally overall size alone is not an indicator. Aboriginal Australians were not much shorter than caucasians, but they had longer legs, shorter spines and where thinner. THeses characteristics may have been more beneficial for migrating great distances than purely temperature related. Aborigines essentially migrated to follow the food.

in summary, as many have highlighted, there is obviously many other physiological and environmental factors they play a role in adapting to climate.

Tom Foley
Reply to  Waza
July 9, 2021 6:41 pm

Aboriginal people of different tribal groups speaking different languages lived on their own specific lands. They moved within their country seasonally, but ‘migration’ gives the wrong impression – it was more circular, like moving around between your main house near the fruit trees and rabbit traps, your winter hunting cabin up in the hills and your summer fishing shack at the beach.

Some areas were quite small and people stayed near reliable food sources such as rivers and lakes, only occasionally moving out into back country. Big cemeteries used over millenia indicate localised if not permanent residence. Some individuals travelled longer distances for trade.

Our perception of Aboriginal people is skewed because the stereotype is the desert dweller, both in population size, distances travelled and body form. But Aboriginal people originally lived in larger more sedentary communities in coastal, riverine areas, those with better soils and rainfall and so with more diverse ecology ie more food, and less need to move long distances.

These are the places where Europeans took over first. The modern population density of Australia, coastal, southeast, southwest and some tropical, pretty much replicates the previous Aboriginal population density. The main exception is the inland rivers which supported very high Aboriginal numbers; this is still a major food-producing area today, but the majority of the people it feeds don’t need live there anymore.

In summary, while Aboriginal people got more exercise in their daily life than today’s couch potatoes, this would have applied to all people in all climates before agriculture, and to many people after.

Waza
Reply to  Tom Foley
July 9, 2021 7:01 pm

Thanks Tom

Jim
July 9, 2021 2:28 pm

Any science used in this study?

jmorpuss
July 9, 2021 2:33 pm

Scientific evidence contradicts findings and assumptions of Canadian Safety Panel 6: microwaves act through voltage-gated calcium channel activation to induce biological impacts at non-thermal levels, supporting a paradigm shift for microwave/lower frequency electromagnetic field action

Abstract

This review considers a paradigm shift on microwave electromagnetic field (EMF)

Scientific evidence contradicts findings and assumptions of Canadian Safety Panel 6: microwaves act through voltage-gated calcium channel activation to induce biological impacts at non-thermal levels, supporting a paradigm shift for microwave/lower frequency electromagnetic field action – PubMed (nih.gov)

michael hart
July 9, 2021 3:34 pm

The very concept of climate change has clearly afflicted the brains of many people.

DMacKenzie,
July 9, 2021 4:20 pm

“Survival of the fittest” and “nutrition” are more direct drivers of human “size” than CC…We don’t understand the results of nutrition changes very well. For example South American Indians were not of large stature, but transplantation of their potatoes to Europe resulted in providing calories that allowed Europeans to enhance their diet resulting in height increase….and starvation when potato crops failed.

Last edited 21 days ago by DMacKenzie,
Chris Hanley
July 9, 2021 4:23 pm

“… The increasing dependence on technology, such as an outsourcing of complex tasks to computers, may cause brains to shrink even more over the next few thousand years …”.
Computers are k.lling human creativity, I’ve seen it in my lifetime.

Tom Foley
Reply to  Chris Hanley
July 9, 2021 6:45 pm

Computers doing away with human creativity? Surely not! Aren’t blogs and comments like these indicators of bigly increased creativity?

Last edited 21 days ago by Tom Foley
Chris*
July 9, 2021 5:46 pm

With regard to this idea that people were bigger during colder periods, this needs some comparisons. Horses for example – those sub species closest to the North Pole are big bodied with short neck and limbs like the Inuit people. Which is more in proportion to a cold climate where warmth of essential organs must be maintained. Whereas horses recognised as from the Afro-Turkic region are finer bodied with proportionately longer neck and limbs, more in keeping with a larger surface area to dissipate heat.

July 9, 2021 6:24 pm

At last we know why the world is full of fat stupid people..

July 9, 2021 7:07 pm

People who believe in dangerous man-made climate change already have very small brains.

Rhs
July 10, 2021 6:21 am

What? The only constant is change? Even evolution isn’t static? Oh the humanity!

Philo
July 10, 2021 8:54 am

About all I can get from this is that smart people know how to get out of the sun better.
Many also fly south like the birds for winter!
Birds are smart, especially parrots which are really smart for a bird, and some humans. They can have a 200+ vocabulary and use it correctly.

To bed B
July 10, 2021 7:54 pm

“Researchers have used data on skeletal remains to calculate how the average height of Englishmen rose or fell over 2,000 years of history. Using data from skeletal remains of men aged between 21 and 49 years from a range of archaeological excavations conducted in different parts of England during the last 30 years, they reconstructed a man’s full height from data recording the length of his femur. …Their working paper reveals that Englishmen became taller when Britain was under Roman occupation (200-410 AD), with average height rising from 167 cm to 170 cm (or 5 feet 5 inches). The researchers suggest this rise in average height coincided with the Romans’ improved water supply and sanitation systems and a more varied diet at this time. After the Romans left Britain in 410, heights did not deteriorate immediately but fell from 600 onwards. The paper highlights previous research suggesting that health may have deteriorated when populations moved out of the towns and cities set up by the Romans, abandoning their more hygienic water supplies and waste disposal systems. Plague and pestilence then became common and infectious diseases are known to have increased at this time, with archaeological evidence also suggesting that diets were inadequate.

Average heights of men started to go up again after the Norman Conquest of 1066, says the paper. By the end of the early medieval period, heights had increased to 172 cm, increasing to 173 cm in the 1100s, edging closer to heights achieved at the start of the 20th century. The paper suggests that a warmer climate may have contributed to good general health among the population, noting that records for 901 until 1100s show that England ‘saw the warmest weather of the millennium’. Over this period of 200 years, average heights increased by more than 5 cm, says the working paper.

After 1200, heights started to decline, and archaeological evidence shows that at this time, the rural populations were decreasing, farmland had become degraded and there were shortages of crop seeds. It also notes that other research has suggested temperatures turned colder over the century, with weather becoming far more changeable until the early 1300s. The early 1300s started with the Great Famine (1315-1317) which may have exaggerated the decline in average heights, but the paper says men had started getting shorter several decades before.”

A much better record of heights and temperature, although of just modern man, that shows the complete opposite correlation. This was height rather volume but likely due to diet so I suspect body weight would have shown a similar increase with warmth and better diet.

To bed B
July 10, 2021 8:15 pm

Interesting comparison with wombats. There are two extant species in the genus Lasiorhinus. The northern and southern hairy -nosed wombat. Both are endemic to semi arid inland regions of Australia. The one living in warmer climes (warmer winters) is about 20% heavier than the southern.

The common wombat is about the size of the southern hary-nosed wombat. It lives in cooler areas at altitude on the mainland as far north as Queensland, and in Tasmania. The Tasmanian population (much cooler) are usually 20% smaller than mainland animals.

All three species are rotund little buggers that are furry and burrow, unlike humans, but it does show it’s not as simple as retaining body heat.

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