News:

if there were no need for 'engineers from the quantum plenum' then we should not have any unanswered scientific questions.

Main Menu

Neanderthals in the News

Started by Recusant, November 10, 2015, 04:47:35 PM

Previous topic - Next topic

Recusant

#15
It may be that the Neanderthals' face/skull morphology is more evolved than ours. That is, they diverged further from the possible common ancestor than we did. This makes sense to me, because I think that the environment they lived in (Europe during the most recent Ice Age) created more evolutionary pressure than the one that the population that we are mostly descended from lived in during the same period (northern Africa).

"Your face is probably more primitive than a Neanderthal's | BBC

QuoteThe question is, when did humans start to look like we do today? New scientific techniques and discoveries are starting to provide answers. But they are also revealing that our distinctive facial features may be far older than many anthropologists originally believed.

[. . .]

"As the last surviving species of humans on the planet, it is tempting to assume our modern faces sit at the tip of our evolutionary branch," says Chris Stringer, an anthropologist at the Natural History Museum in London, as he joins me in the gallery.

"And for a long time, that has been what the fossils seemed to indicate," he continues. "Around 500,000 years ago, there was a fairly widespread form of Homo heidelbergensis that has a face somewhat intermediate between that of a modern human and Neanderthals. For a long time, I argued this was our common ancestor with Neanderthals."

[. . .]

For decades, most anthropologists agreed that Neanderthals had retained many of these features from H. heidelbergensis as they evolved and developed a more protruding jaw, while our own species went in a different direction. That was until the 1990s, when a puzzling discovery was unearthed in the Sierra de Atapuerca region of northern Spain.

In a sinkhole in the mountains, fragments of a small, flat-faced skull were unearthed, alongside several other bones. The remains were identified as belonging to a previously unknown species of hominin. It was called Homo antecessor.

At first, this apparent contradiction was hand-waved away. The Atapuerca skull belonged to a child, aged around 10 to 12 years old. It is difficult to predict what this youngster's face would have looked like in adulthood, because as humans age their skulls grow and change shape. "It was assumed that it would fill out and grow into something resembling heidelbergensis," says Stringer.

However, later discoveries suggest this is not the case. "We now have four fragments from antecessor adult and sub-adult skulls," says Stringer. "It looks like they maintain the morphology we see in the child's skull."

The face of this new species of human ancestor appeared to be far more like our own, and even had the distinctive hollowing of the canine fossa. Yet it lived 850,000 years ago, well before H. heidelbergensis.

[. . .]

[Jean-Jaques] Hublin [of the Max Planck Institute for Evolutionary Anthropology] thinks that modern humans have retained a lot of primitive features from our distant ancestors. "It seems the Neanderthals are more evolved in their own direction than modern humans," he says. "They would have looked very peculiar to our eyes."

In other words, the faces of modern humans may not be all that modern at all.

[Continues . . .]
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


xSilverPhinx

Interesting. It's generally thought that modern human's facial characteristics evolved through neoteny.
I am what survives if it's slain - Zack Hemsey


Dave

#17
I was wondering about the Mongoloid adaptations to cold weather: the smaller ears and nose compared with, say, the Caucasian group, plus the "slitted" eyes and the protective aspects of the epicanthic fold.

If the large nose of the Neanderthal is, IIRC, to help warm incoming air. This seems contrary, unless the windchill factor was more important in the colder parts of Asia than Europe (keep forgetting just how cold it gets in Japan and N. Korea, let alone Mongolia itself and high in the Asian mountains.)

Caucasians seem to fall between Negroid and Mongolian in some respects of head morphology, especially the nose?

Whatever works will survive! Could be more than one solution to a problem.
Tomorrow is precious, don't ruin it by fouling up today.
Passed Monday 10th Dec 2018 age 74

xSilverPhinx

#18
I'm wondering about this too now. :lol:

Especially considering the mongoloid nose is flatter than Caucasians, in general. I don't know if their turbinates are the same. :notsure:

There could be other mechanisms at work, such as sexual selection, but I don't know.  Just thinking aloud.
I am what survives if it's slain - Zack Hemsey


Dave

Quote from: xSilverPhinx on February 20, 2017, 09:58:11 PM
I'm wondering about this too now. :lol:

Especially considering the mongoloid nose is flatter than Caucasians, in general. I don't know if their turbinates are the same. :notsure:

There could be other mechanisms at work, such as sexual selection, but I don't know.  Just thinking aloud.

The more prominent the features the more prone they are to frostbite, especially in windy conditions.
Tomorrow is precious, don't ruin it by fouling up today.
Passed Monday 10th Dec 2018 age 74

Recusant

I indulged in speculation in my intro to the BBC piece. The changes in Neanderthals' skull morphology may have had little to do with evolutionary pressure from their environment. Maybe it was sexual selection, or maybe the genes that changed to produce the different morphology conferred some advantage not directly related to the morphology. It's also possible that the change was due to nothing more than genetic drift. I've looked around, and it appears that as yet there's no scientific consensus regarding this issue.
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Dave

Seems Neanderthal noses are a subject of some speculation.

QuoteThe Neanderthal's huge nose is a fluke of evolution, not some grand adaptation, research suggests.

https://www.newscientist.com/article/dn15042-why-did-neanderthals-have-such-big-noses/
Tomorrow is precious, don't ruin it by fouling up today.
Passed Monday 10th Dec 2018 age 74

Recusant

The continuing contribution of Neanderthals to the way the genes of non-African population are expressed is described in a new paper: "Neanderthal DNA contributes to human gene expression" | PHYS.ORG

QuoteThe last Neanderthal died 40,000 years ago, but much of their genome lives on, in bits and pieces, through modern humans. The impact of Neanderthals' genetic contribution has been uncertain: Do these snippets affect our genome's function, or are they just silent passengers along for the ride? In Cell on February 23, researchers report evidence that Neanderthal DNA sequences still influence how genes are turned on or off in modern humans. Neanderthal genes' effects on gene expression likely contribute to traits such as height and susceptibility to schizophrenia or lupus, the researchers found.

"Even 50,000 years after the last human-Neanderthal mating, we can still see measurable impacts on gene expression," says geneticist and study co-author Joshua Akey of the University of Washington School of Medicine. "And those variations in gene expression contribute to human phenotypic variation and disease susceptibility."


[Continues . . .]

The full paper is available for free: "Impacts of Neanderthal-Introgressed Sequences on the Landscape of Human Gene Expression" | Cell

Summary from the paper:

QuoteRegulatory variation influencing gene expression is a key contributor to phenotypic diversity, both within and between species. Unfortunately, RNA degrades too rapidly to be recovered from fossil remains, limiting functional genomic insights about our extinct hominin relatives. Many Neanderthal sequences survive in modern humans due to ancient hybridization, providing an opportunity to assess their contributions to transcriptional variation and to test hypotheses about regulatory evolution. We developed a flexible Bayesian statistical approach to quantify allele-specific expression (ASE) in complex RNA-seq datasets. We identified widespread expression differences between Neanderthal and modern human alleles, indicating pervasive cis-regulatory impacts of introgression. Brain regions and testes exhibited significant downregulation of Neanderthal alleles relative to other tissues, consistent with natural selection influencing the tissue-specific regulatory landscape. Our study demonstrates that Neanderthal-inherited sequences are not silent remnants of ancient interbreeding but have measurable impacts on gene expression that contribute to variation in modern human phenotypes.
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Ecurb Noselrub

Let's not forget the "prestigious man" phenomenon.  http://www.iflscience.com/health-and-medicine/least-ten-other-men-are-fruitful-genghis-khan/    Guys like Genghis Khan have lots of children with lots of women, so they leave lots of genes in the gene pool.  Their characteristics get carried on just because they were prestigious men in their times.  So maybe there was a Neanderthal ruler who happened to have a big nose, and his genes ended up in his children and children's children because of his position.

Dave

Maybe.

QuoteA cave in northern Spain that previously yielded evidence of Neanderthals as brain-eating cannibals now suggests the prehistoric humans ate their greens and used herbal remedies.

A new study of skeletal remains from El Sidrón cave site in Asturias (map) detected chemical and food traces on the teeth of five Neanderthals
QuoteThe cave dwellers' diet was found to include yarrow and chamomile, both bitter-tasting plants with little nutritional value. Earlier research by the same team had shown that the Neanderthals in El Sidrón had a gene for tasting bitter substances.

"We know that Neanderthals would find these plants bitter, so it is likely these plants must have been selected for reasons other than taste"—probably medication, Hardy said in a statement.

"It fits in well with the behavioral pattern of self-medication by today's higher primates, and indeed many other animals."

http://news.nationalgeographic.com/news/2012/07/120720-neanderthals-herbs-humans-medicine-science/#close

Tomorrow is precious, don't ruin it by fouling up today.
Passed Monday 10th Dec 2018 age 74

Recusant

This story has a number of different aspects to it. I was going to add a post to the "Neanderthals in the News" thread, but will put it here.  :)

"Neanderthals may have medicated with penicillin and painkillers" | New Scientist

QuoteWhat a difference 1000 kilometres make. Neanderthals living in prehistoric Belgium enjoyed their meat – but the Neanderthals who lived in what is now northern Spain seem to have survived on an almost exclusively vegetarian diet.

This is according to new DNA analysis that also suggests sick Neanderthals could self-medicate with naturally occurring painkillers and antibiotics, and that they shared mouth microbiomes with humans – perhaps exchanged by kissing.

Neanderthals didn't clean their teeth particularly well – which is lucky for scientific investigators. Over time, plaque built up into a hard substance called dental calculus, which still clings to the ancient teeth even after tens of thousands of years.

Researchers have already identified tiny food fragments in ancient dental calculus to get an insight into the diets of prehistoric hominins. Now Laura Weyrich at the University of Adelaide, Australia, and her colleagues have shown that dental calculus also carries ancient DNA that can reveal both what Neanderthals ate and which bacteria lived in their mouths.

[Continues . . .]

"Some Neanderthals Were Vegetarian — And They Likely Kissed Our Human Ancestors" | NPR

QuoteLuckily for researchers, there is an abundance of Neanderthal teeth in the fossil record. "We have complete jaws with teeth, we have upper jaws with skulls with teeth intact, isolated teeth," says Keith Dobney, an archaeologist at the University of Liverpool.

He and his colleagues have been studying Neanderthal dental plaques — or rather, the hardened version of plaque, tartar, or what scientists call dental calculus. They scraped off some of the calculus and analyzed the DNA that was preserved in it for clues to what the Neanderthals ate.

They looked at plaques from the teeth of three Neanderthals living in Europe about 50,000 years ago. One individual was from a cave in Spy, Belgium, and the other two were from El Sidrón cave in Spain.

As they report in a study published in this week's Nature, the Belgian individual ate mostly meat. "We found evidence of woolly rhino. We found the DNA of wild sheep," says Dobney.

The researchers also found evidence of mushrooms, but this was certainly a meat lover. This isn't that surprising to scientists who study Neanderthal diets. After all, the butchered bones of woolly rhinos, mammoths, horses and reindeer had been found in the Spy cave and other sites, suggesting a meat-heavy diet.

There had also been other indirect sources of evidence of carnivory, like high levels of a certain nitrogen isotopes, which suggested meat- and/or mushroom-heavy diets.

"Most Neanderthals that had been analyzed [before] were really heavy meat eaters," says Laura Weyrich, at the Australian Center for Ancient DNA at the University of Adelaide, Australia, and the lead author on the new study. She says those previous studies had suggested that "Neanderthals were as carnivorous as polar bears."

And this is where the new study offered a big surprise. According to the DNA in dental plaques, the Neanderthals in Spain ate no meat at all.

"We find things like pine nuts, moss, tree barks and even mushrooms as well," says Weyrich. "It is very indicative of a vegetarian diet, probably the true Paleo diet." (Not all of the region's Neanderthals were necessarily vegetarians: The El Sidrón cave also contained grisly evidence of cannibalism.)

She says the difference in diets reflects the fact that the two groups lived in two very different environments.

[Continues . . .]

If you go to the NPR article and click on the link to the original paper (where "a study" is bolded in my quote) you can get access to the full paper via an automatic redirect. I can't link directly to it from here.
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Dave

 Oops, missed the "Neanderthals in the news" thread or I would have puut it there.

Stuck this in there if you wish, Recusant.
Tomorrow is precious, don't ruin it by fouling up today.
Passed Monday 10th Dec 2018 age 74

Recusant

Not a science story, but interesting none the less, in my opinion.  ;)

An interview with Claire Cameron, the author of The Last Neanderthal:

"The new Neanderthals" | Maclean's

Quote

'Nana & Flint' are forensic reconstructions of the Gibraltar 1 (Forbes' Quarry, 1848) and
Gibraltar 2 (Devil's Tower Shelter Cave, 1926) Neanderthal fossils by Dutch artists Kennis & Kennis.
Image Credit: S. Finlayson

Toronto novelist Claire Cameron, whose 2014 bestseller The Bear took place in the contemporary Canadian wilderness, moves across time and space to an equally dangerous locale for The Last Neanderthal, set in France 40,000 years ago. The intricate tale of Girl, the title character, and Rose, the modern-day archaeologist who discovers her bones, is a story of common humanity, including the fact that the more things change for pregnant women, the more they stay the same. The novel is also thoroughly immersed in the recent explosion in knowledge—and speculation—about our closest kin. Cameron spoke with Maclean's about the lives and fate of the Neanderthals.

Q: You note that Neanderthal—"stooped over, hairy, primitive, dull"—is still an insult in use, but our cousins have been picking up a lot of good press lately. Why are we so fascinated?

A: Since 2010, yes, and the first draft of the genome. That really changed the perception. They're almost like a Shakespearean foil now. We can see ourselves in them.

Q: And we did see them, literally. That makes a difference.

A: It's the interbreeding between the two groups that really takes it up a notch: between one and four per cent of European and Asian DNA is Neanderthal.

Q: So, as usual, it's all about us. What did we get out of this genome infusion? Red hair, which Girl has, has caught the popular imagination.

A: We are a self-centred storytelling species, aren't we? Yes, there's the red hair, though that comes from a small sample. Scientists are starting to look into things like immunity. For genes to stick around, they do need to play some sort of role often—not always—but there are all sorts of things in the news at the moment about what and why.

[Continues . . .]
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Recusant

It looks like there's a new way to investigate the history of our ancestors.

"Long After Their Bones Were Gone, Neanderthals' DNA Survived in a Cave" | Live Science

QuoteDNA from two extinct human relatives — the Neanderthals, and a mysterious branch of humanity called the Denisovans — has been detected in the ancient mud of caves, even though those caves hold no fossils of those individuals, new research shows.

The finding suggests that scientists could detect such extinct lineages in places devoid of skeletal remains, the researchers said. This technique, if verified, could fill blank spots in scientists' understanding of how and where humans evolved, according to the authors of the new study describing the finding.

[Continues . . .]
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Recusant

Differences and similarities in the ways that Neanderthals grew and anatomically modern humans grow are explored in a new study:

"Reconstructing how Neanderthals grew, based on an El Sidrón child" | ScienceDaily

QuoteHow did Neanderthals grow? Does modern man develop in the same way as Homo neanderthalensis did? How does the size of the brain affect the development of the body? Researchers have studied the fossil remains of a Neanderthal child's skeleton in order to establish whether there are differences between the growth of Neanderthals and that of sapiens.

According to the results of the article, which are published in Science, both species regulate their growth differently to adapt their energy consumption to their physical characteristics.

"Discerning the differences and similarities in growth patterns between Neanderthals and modern humans helps us better define our own history. Modern humans and Neanderthals emerged from a common recent ancestor, and this is manifested in a similar overall growth rate," explains CSIC researcher, Antonio Rosas, from Spain's National Natural Science Museum (MNCN). As fellow CSIC researcher Luis Ríos highlights, "Applying paediatric growth assessment methods, this Neanderthal child is no different to a modern-day child." The pattern of vertebral maturation and brain growth, as well as energy constraints during development, may have marked the anatomical shape of Neanderthals.

Neanderthals had a greater cranial capacity than today's humans. Neanderthal adults had an intracranial volume of 1,520 cubic centimetres, while that of modern adult man is 1,195 cubic centimetres. That of the Neanderthal child in the study had reached 1,330 cubic centimetres at the time of his death, in other words, 87.5% of the total reached at eight years of age. At that age, the development of a modern-day child's cranial capacity has already been fully completed.

"Developing a large brain involves significant energy expenditure and, consequently, this hinders the growth of other parts of the body. In sapiens, the development of the brain during childhood has a high energetic cost and, as a result, the development of the rest of the body slows down," Rosas explains.

[Continues . . .]
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken