Author Topic: Homo sapiens and Their Cousins  (Read 2525 times)

Recusant

  • Miscreant Erendrake
  • Administrator
  • Guardian of Reason
  • *****
  • Posts: 5564
  • Gender: Male
  • infidel barbarian
Homo sapiens and Their Cousins
« on: October 31, 2015, 01:52:11 AM »
These two stories don't actually belong in the "Neanderthals in the News" thread, so it doesn't matter too much that it's missing at the moment. The first is about Denisova Cave, in which fossils of the interesting species now known as Denisovans were found.


Denisovans occupied Denisova Cave more than once, at least 65,000 years apart. Neandertals slipped in
as well, and modern humans were the last to live there. Image Credit: Max Planck Institute for Evolutionary Anthropology

"Siberian cave was home to generations of mysterious ancient humans" | Science

Quote
In 2010, scientists discovered a new kind of human by sequencing DNA from a girl’s pinky finger found in Denisova Cave in Siberia. Ever since, researchers have wondered when the girl lived, and if her people, called Denisovans, lingered in the cave or just passed through. But the elusive Denisovans left almost no fossil record—only that bit of bone and a handful of teeth—and they came from a site that was notoriously difficult to date.

Now, state-of-the-art DNA analysis on the Denisovan molars and new dates on cave material show that Denisovans occupied the cave surprisingly early and came back repeatedly. The data suggest that the girl lived at least 50,000 years ago and that two other Denisovan individuals died in the cave at least 110,000 years ago and perhaps as early as 170,000 years ago, according to two talks here last week at the meeting of the European Society for the study of Human Evolution. Although the new age estimates have wide margins of error, they help solidify our murky view of Denisovans and provide “really convincing evidence of multiple occupations of the cave,” says paleoanthropologist Fred Spoor of University College London. “You can seriously see it’s a valid species.”

[Continues . . .]

The next story is about a very intriguing find in China of Homo sapiens teeth. What's interesting is that these teeth appear to be from an era before there is any evidence of anatomically modern humans in Europe.

"The earliest unequivocally modern humans in southern China" | Nature (PDF) < I hope that link works. It's to an article that was put online as part of a "sharing initiative."

Quote
Our study shows that fully modern morphologies were present in southern China 30,000-70,000 years earlier than in the Levant and Europe. Our data fill a chronological and geographical gap that is relevant for understanding when H. sapiens first appeared in southern Asia. The Daoxian teeth also support the hypothesis that during the same period, southern China was inhabited by more derived populations than central and northern China. This evidence is important for the study of dispersal routes of modern humans. Finally, our results are relevant to exploring the reasons for the relatively late entry of H. sapiens into Europe.

[Continues . . .]
« Last Edit: June 09, 2016, 02:58:04 AM by Recusant »
"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


Icarus

  • The wise one.
  • Blessing Her Holy Hooves
  • *****
  • Posts: 4528
Re: Homo sapiens and Their Cousins
« Reply #1 on: October 31, 2015, 05:01:17 AM »
Remarkable stuff.  Thanks for the reference.


Recusant

  • Miscreant Erendrake
  • Administrator
  • Guardian of Reason
  • *****
  • Posts: 5564
  • Gender: Male
  • infidel barbarian
Re: Homo sapiens and Their Cousins
« Reply #2 on: November 18, 2015, 09:13:33 PM »
More Denisovan DNA has been sequenced, so now there are three known examples.

"Nuclear and mitochondrial DNA sequences from two Denisovan individuals" | PNAS

Quote
Significance

Denisovans are a sister group of Neandertals that were identified on the basis of a nuclear genome sequence from a bone from Denisova Cave (Siberia). The only other Denisovan specimen described to date is a molar from the same site. We present here nuclear DNA sequences from this molar and a morphological description, as well as mitochondrial and nuclear DNA sequences from another molar from Denisova Cave, thus extending the number of Denisovan individuals known to three. The nuclear DNA sequence diversity among the Denisovans is higher than among Neandertals, but lower than among present-day humans. The mtDNA of one molar has accumulated fewer substitutions than the mtDNAs of the other two specimens, suggesting Denisovans were present in the region over several millennia.

The full paper is available as a PDF at the link.
"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

  • Miscreant Erendrake
  • Administrator
  • Guardian of Reason
  • *****
  • Posts: 5564
  • Gender: Male
  • infidel barbarian
Re: Homo sapiens and Their Cousins
« Reply #3 on: December 22, 2015, 04:52:28 PM »
Some very interesting finds have been made in China which could indicate that an archaic hominin species survived there until relatively recently; even later than the last Neanderthals and Denisovans. There are some possibly rather kinky sides to this story as well.

"New species of human may have shared our caves – and beds" | New Scientist

Quote
One of the most exciting pieces of evidence in the story is a hominin femur found in Muladong cave in south-west China, alongside other human and animal bones. It shows evidence of having been burned in a fire that was used for cooking other meat, and has marks consistent with it being butchered for consumption.

It has also been broken in a way that is often used to access the bone marrow.

Unusually, it had been painted with a red clay called ochre, something often associated with burial rituals. While many other bones were eaten in the cave, only the ones from human species were painted.

It’s hard to know if the bone was actually cannibalised by the H. sapiens whose remains have also been found in the area, Curnoe says, but all the evidence points towards that conclusion.

“We don’t know it was cannibalism,” he says. “We’ve got cut marks that would be consistent with butchering.”

But things got interesting when the team tried to identify the bone. “Our work shows clearly that the femur resembles archaic humans,” Curnoe says. Yet the sediment the bone was found in dated to just 14,000 years ago.

The shaft of the bone is very narrow and it has a thin outer layer, yet the walls are reinforced in areas of high strain. There is also a notch where muscle would have joined the bone, which is much larger than in anatomically modern humans, and it faces more towards the back of the bone (see photo, above).

“These features suggest it walked differently,” says Curnoe. And judging by the size of the bone, Curnoe estimates the adult human would have weighed about 50 kilograms – much smaller than other known Ice Age humans.

“When you put all the evidence together the femur comes out quite clearly resembling the early members of Homo,” says Curnoe.

If confirmed, says Petraglia, this would change our understanding of human evolution.

[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

  • Miscreant Erendrake
  • Administrator
  • Guardian of Reason
  • *****
  • Posts: 5564
  • Gender: Male
  • infidel barbarian
Re: Homo sapiens and Their Cousins
« Reply #4 on: February 17, 2016, 12:30:48 AM »
After analysing the skulls of Homo floriensis, the diminutive former inhabitants of the island of Flores popularly known as "hobbits" (I think the scare quotes are part of the name, now  ;)), a pair of French scientists have concluded that they are indeed a distinct species, rather than an offshoot of Homo sapiens.

"Mystery 'hobbits' not humans like us: study" | PHYS.ORG

Quote


The remains of Indonesia's hobbit-sized humans (L) and modern human (R) are
displayed at Gadjah Mada University in Yogyakarta, Indonesia on November 5, 2004

Quote
Diminutive humans that died out on an Indonesian island some 15,000 years ago were not Homo sapiens but a different species, according to a study published Monday that dives into a fierce anthropological debate.

Fossils of Homo floresiensis—dubbed "the hobbits" due to their tiny stature—were discovered on the island of Flores in 2003.

Controversy has raged ever since as to whether they are an unknown branch of early humans or specimens of modern man deformed by disease.

The new study, based on an analysis of the skull bones, shows once and for all that the pint-sized people were not Homo sapiens, according to the researchers.

Until now, academic studies have pointing in one direction or another—and scientific discourse has sometimes tipped over into acrimony.

One school of thought holds that so-called Flores Man descended from the larger Homo erectus and became smaller over hundreds of generations.

[. . .]

But other researchers argue that H. floresiensis was in fact a modern human whose tiny size and small brain—no bigger than a grapefruit—was caused by a genetic disorder.

[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


Tank

  • Fed up with stupid.
  • Administrator
  • Excellent and Indefatigable Guardian of Reason
  • *****
  • Posts: 28810
  • Gender: Male
Re: Homo sapiens and Their Cousins
« Reply #5 on: February 17, 2016, 08:14:52 AM »
I tend towards the conclusion that they are missing, or avoiding for some weird reason, the bleeding obvious; natural selection. It's always there and always shaping organisms.
If religions were TV channels atheism is turning the TV off.
“Religion is a culture of faith; science is a culture of doubt.” ― Richard P. Feynman
'It is said that your life flashes before your eyes just before you die. That is true, it's called Life.' - Terry Pratchett

Recusant

  • Miscreant Erendrake
  • Administrator
  • Guardian of Reason
  • *****
  • Posts: 5564
  • Gender: Male
  • infidel barbarian
Re: Homo sapiens and Their Cousins
« Reply #6 on: June 09, 2016, 03:07:35 AM »
Speaking of Homo floresiensis, it may be that they weren't around as recently as indicated by the previous estimate.

"Age of 'Hobbit' species revised" | BBC

Quote
The discovery of Homo floresiensis in 2003 caused a sensation because it seemed the creature could have been alive in the quite recent past.

But a new analysis indicates the little hominin probably went extinct at least 50,000 years ago - not the 12,000 years ago initially thought to be the case.

Researchers report their revised assessment in the journal Nature [go to the BBC page for a link that will take you to the full paper].

Prof Bert Roberts, from the University of Wollongong, Australia, says the new dating actually resolves what had always been a head-scratcher: how it was possible for floresiensis to survive for 30,000 to 40,000 years after modern humans are believed to have passed through Indonesia.

"Well, it now seems we weren't living alongside this little species for very long, if at all. And once again it smells of modern humans having a role in the downfall of yet another species," he told BBC News.

"Every time modern humans arrived somewhere new, it tended to be bad news for the endemic fauna. Things would go pear-shaped pretty quickly."

[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

  • Miscreant Erendrake
  • Administrator
  • Guardian of Reason
  • *****
  • Posts: 5564
  • Gender: Male
  • infidel barbarian
Re: Homo sapiens and Their Cousins
« Reply #7 on: July 19, 2016, 05:11:19 PM »
Intriguing story about the identity of the first human farmers.

"The world's first farmers were surprisingly diverse" | Science

Quote
Ancient DNA has a way of uncovering complexity in seemingly simple stories of our past. Most famously, it has shown that modern humans didn’t simply replace our archaic cousins as we spread across the world; we interbred with them along the way. Now, this method is adding nuance to the story of farming, long known to have originated in the Fertile Crescent of the Middle East.

According to three teams who used new techniques to gain glimpses of the nuclear DNA of the world’s very first farmers, farming was adopted not by one group of people, but by genetically distinct groups scattered across the region. “It was not one early population that sowed the seeds of farming in western Asia, but several adjacent populations that all had the good fortune to live in the zone where potential plant and animal domesticates were to be found and exploited,” says archaeologist Colin Renfrew of the University of Cambridge in the United Kingdom, who was not involved in the work.

The research—a paper published online in Science this week and two studies posted last month on the bioRxiv server—can’t pin down whether agriculture spread quickly among diverse peoples or was independently invented more than once. But the diversity of the first farmers is “very surprising,” says statistical geneticist Garrett Hellenthal of University College London, a co-author of the Science paper. “These early farmers who lived pretty close to each other were 
completely different.”

[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


Dave

  • Formerly known as Gloucester
  • Blessing Her Holy Hooves
  • *****
  • Posts: 4244
  • Gender: Male
Re: Homo sapiens and Their Cousins
« Reply #8 on: July 19, 2016, 05:22:47 PM »
One wonders how much travelling and trading went on between adjacent and nearby genetic groups? This could be responsible for culture spread between the groups over time periods too quick, in archaeological terns, to differentiate.
Tomorrow is precious, don't ruin it by fouling up today.

Recusant

  • Miscreant Erendrake
  • Administrator
  • Guardian of Reason
  • *****
  • Posts: 5564
  • Gender: Male
  • infidel barbarian
Re: Homo sapiens and Their Cousins
« Reply #9 on: July 19, 2016, 05:39:57 PM »
One wonders how much travelling and trading went on between adjacent and nearby genetic groups? This could be responsible for culture spread between the groups over time periods too quick, in archaeological terns, to differentiate.

Yes, that seems to be the most reasonable hypothesis.

Speaking of early farming, the gene sequence of some truly ancient barley has been produced and analysed. Apparently, 6,000 years ago, barley was already pretty much fully domesticated, and hasn't changed much since then.

"Ancient barley DNA gives insight into crop development" | BBC

Quote
An international group of scientists have analysed the DNA of 6,000 year old barley finding that it is remarkably similar to modern day varieties.

They say it could also hold the key to introducing successful genetic variation.

Due to the speed at which plants decompose, finding intact ancient plant DNA is extremely rare.

The preserved ancient barley was excavated near the Dead Sea, the journal Nature Genetics reports.
The arid environment conserved the biological integrity of the grains, the paper says.

[Continues . . .]

If you go to the BBC, you can click through on the link in the story to a page that will redirect to the full paper.
"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


Icarus

  • The wise one.
  • Blessing Her Holy Hooves
  • *****
  • Posts: 4528
Re: Homo sapiens and Their Cousins
« Reply #10 on: July 20, 2016, 12:04:38 AM »
Though surely not the first agriculturists, the Sumerians are perhaps the early developers of commercial and governmental functions.  Sumeria was a collection of homesteads and villages in the south of what is now Iraq, between the Tigres and Euphrates rivers, the spectacularly fertile area of the middle east.  Agriculture was the reason for settlement there. Each farmer could and did produce more than he needed for his own subsistence. Others who produced wheels or the necessary basketry or metal work could trade with the agriculturists. Sometimes there was a different value of goods or hardware involved in the trade. The Sumerians conceived of the idea of coinage to offset the difference of trade values.

Pretty soon there were disputes about the value of coinage. The elders decided to install a set of judges who could settle disputes. Someone had to have authority over the judges, and leaders were appointed. Governors or even kings. Well sometimes there were short or long term disputes or even confrontations that needed quick response to preserve a semblance of peace, the police force or its predecessor was invented and implemented.

Villages to the north coveted the villages of the south and visa versa. Oh shit! War. Armies were made by conscripting the young males.  They fought as commanded or when necessary.

All this took place wa...a....ay before Moses. The Sumerians were perhaps among the first people who sought to establish a civilized, cooperative, social system. That was well before Mohammed and his Flying horse. All that was because the fertile crescent was capable of producing more crops than a single family needed. 

That is a most simplistic tale of the development of a workable society that had its roots in agriculture. It does not take into account the development of the far eastern cultures in places like what is now China.


OldGit

  • Ich em alder thene ich wes awintre and ech a lare
  • The Cure for Boredom is Curiosity. There is No Cure For Curiosity.
  • *****
  • Posts: 10784
  • Gender: Male
  • No amount of belief makes something a fact.
Re: Homo sapiens and Their Cousins
« Reply #11 on: July 20, 2016, 08:53:14 AM »
When did the lawyers sneak in?

Dave

  • Formerly known as Gloucester
  • Blessing Her Holy Hooves
  • *****
  • Posts: 4244
  • Gender: Male
Re: Homo sapiens and Their Cousins
« Reply #12 on: July 20, 2016, 08:55:22 AM »
Though surely not the first agriculturists, the Sumerians are perhaps the early developers of commercial and governmental functions. 

Right, so we can blame the Sumerians for all the crappy bureaucracy, greed and politics in the world then, they invented it!?

 ;)
Tomorrow is precious, don't ruin it by fouling up today.

Recusant

  • Miscreant Erendrake
  • Administrator
  • Guardian of Reason
  • *****
  • Posts: 5564
  • Gender: Male
  • infidel barbarian
Re: Homo sapiens and Their Cousins
« Reply #13 on: July 30, 2016, 05:32:17 PM »
Evidence of cancer in our hominin relatives/ancestors:

"Cancer on a Paleo-diet? Ask someone who lived 1.7 million years ago" | ScienceDaily

Quote
An international team of researchers led by scientists from the University of the Witwatersrand's Evolutionary Studies Institute and the South African Centre for Excellence in PalaeoSciences today announced in two papers, published in the South African Journal of Science, the discovery of the most ancient evidence for cancer and bony tumors yet described in the human fossil record.

The discovery of a foot bone dated to approximately 1.7 million years ago from the site of Swartkrans with definitive evidence of malignant cancer, pushes the oldest date for this disease back from recent times into deep prehistory. Although the exact species to which the foot bone belongs is unknown, it is clearly that of a hominin, or bipedal human relative.

[. . .]

Prof. Lee Berger, an author on both papers and leader of the Malapa project where the fossil vertebra was found adds "not only has there been an assumption that these sorts of cancers and tumors are diseases of modernity, which these fossils clearly demonstrate they are not, but that we as modern humans exhibit them as a consequence of living longer, yet this rare tumor is found in a young child. The history of these types of tumors and cancers is clearly more complex than previously thought."

[Continues . . .]

Both papers are free access:

"Earliest hominin cancer: 1.7-million-year-old osteosarcoma from Swartkrans Cave, South Africa"

"Osteogenic tumour in Australopithecus sediba: Earliest hominin evidence for neoplastic disease"
"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


Icarus

  • The wise one.
  • Blessing Her Holy Hooves
  • *****
  • Posts: 4528
Re: Homo sapiens and Their Cousins
« Reply #14 on: July 31, 2016, 03:01:25 AM »
Mr Deity has some shrewd comedy. The link had him use the term; flustercluck which is a yukker for me (the dirty old man)

 Not to diminish the relevance of the more serious science links. Cancer is not so funny.

Rec, I appreciate that you tend to think on a somewhat elevated level and that you share your discoveries with us.