This is interesting - early humans may have hibernated.
Seasonal damage in bone fossils in Spain suggest Neanderthals and their predecessors followed the same strategy as cave bears
www.theguardian.com
Puddy_Tat may be able to use this as justification for sleeping through the winter.
Calling them "human" is getting into questions over who is human. Gernally their has been a restriction of its use to H. sapiens.
At 4-500 000 years ago they would have been on the cusp of H. heidelbergensis and H. neanderthal. Its far more likely this is a extinct off shoot of the Homo family bush.
The idea of Hominina hibernation raises some big questions. Firstly primates pretty much lost the ability to synthesis vitamin C about 60 million years ago and we know humans cannot synthesis vitamin D without sunlight on the skin. Any period of a couple of months without food sources to supplement (given the creatures remaining in a torpor away from the sun) would lead to annual malnutrition.
We have other minerals that are vital to body function we need to keep topped up. People trying extended fasts of a couple of weeks can run into health problems if they do not supplement for vital nutrients.
We know humans need about 1800kcal a day for basal metabolic activities including brain activity. Our brain burns away at about 300kcal. Its a pretty expensive organ to have parked up doing nothing. H heidelbergensis would have had a smaller brain. But not that much smaller. At 1800kcal you are burning about 1kg of body fat every 4 days. Physiological adaptations to induce actual hibernation including lowering body temperature (and surviving) are huge. It would require major changes in cell and organ chemistry.
How they jumped to hominids sprouting hibernation in one location rather than finding evidence for seasonal starvation is not mentioned in the article.
These were found in Spain, this is not somewhere we associated with SAD (Seasonal Affected Disorder), though it likely does occur there. SAD is a relatively well described pathology, it is down to a disturbance in the circadian rhythm caused by the short duration of sun at high latitudes (basically northern ones) and the relatively low levels of artificial light indoors (being outdoors in daylight for an hour or so likely helps reduce the symptoms in many cases). The bodies production of serotonin and its transformation into melatonin through the daylight and into the evening is disturbed. This is likely magnified by our usage of artificial light and stimulation into the evening. As this seems to be well observed in people with recent African or South Asian origin then there seems no way for this to have any kind of "evolutionary adaptation", rather its a mixture of us living outside or more normal range and the disturbances of modern life.
We only recently pushed into these high northern latitudes as the great glaciers retreated at the end of the last glaciation. The one evolutionary adaptation people think may have happened is a loss of melanin in the skin to aid the absorption of sunlight for vitamin D production.
As for hibernation in H. sapiens in the modern era, this is far more likely to have been the annual starvation of agrarian peasants as food stocks run low over winter. There is a strong abundance of evidence of widespread chronic (that is sustained over much of their lives) malnutrition of people in the period before last century or so. Most families would go through a few winters where at least one of the children did not make it. Calling that "hibernation" is callous.
That's an incredible find
2020's winner for Unprovoked Moral Grandstanding!
