Mythopoeika
I am a meat popsicle
- Joined
- Sep 18, 2001
- Messages
- 53,227
- Location
- Inside a starship, watching puny humans from afar
Polo. The mint with the hole.
Scientists Have Found the Oldest Known Human Fossils
The 300,000-year-old bones and stone tools were discovered in a surprising place—and could revise the history of our species.
Their presence in north Africa complicates what was once a tidy picture of humanity arising in the east of the continent. “What people, including myself, used to think was that there was a cradle of humankind in East Africa about 200,000 years ago, and all modern humans descend from that population,” says Philipp Gunz from the Max Planck Institute for Evolutionary Anthropology, who was involved in the new excavation. “The new finds indicate that Homo sapiens is much older and had already spread across all of Africa by 300,000 years ago. They really show that the African story of our species was more complex than what we used to think.”
These people had very similar faces to today’s humans, albeit with slightly more prominent brows. But the backs of their heads were very different. Our skulls are rounded globes, but theirs were lower on the top and longer at the back. If you saw them face on, they could pass for a modern human. But they turned around, you’d be looking at a skull that’s closer to extinct hominids like Homo erectus. “Today, you wouldn’t be able to find anyone with a braincase that shape,” says Gunz.
More on Human-Neanderthal interbreeding, possibly going back more than 200,00 years.
We may have mated with Neanderthals more than 219,000 years ago
It’s a sex-laced mystery. If modern humans didn’t reach Europe until about 60,000 years ago, how has DNA from them turned up in a Neanderthal fossil in Germany from 124,000 years ago?
The answer seems to be that there was a previous migration of early humans – more than 219,000 years ago. One that we’re only just starting to reveal from piecemeal evidence that is DNA extracted from fossilised bones.
The story, as far as we knew it, was that the ancestors of modern humans diverged from Neanderthals and Denisovans between 550,000 and 765,000 years ago. While Neanderthals and Denisovans inhabited Eurasia, modern humans stayed in Africa until about 60,000 years ago. Then they entered Europe, too. ...
https://www.newscientist.com/articl...id=SOC|NSNS|2017-Echobox#link_time=1499246692
Learn more at New Scientist Live in London Come see our expert talk: ‘Why is there only one species of human?’
There is ample evidence of breeding between Neanderthals and the ancestors of modern humans some 50,000 years ago. “Everyone knows Neanderthals gave us genes,” says Cosimo Posth at the Max Planck Institute for the Science of Human History in Leipzig, Germany.
... The more we uncover about human evolution, the more mysterious and convoluted the story becomes.
In particular, some tools were sandwiched in ash from the famous Toba eruption that geologists can date very accurately to 74,000 years ago.
Early humans may have seen a supervolcano explosion up close
... Many archaeologists were puzzled by the recent discovery of 65,000-year-old stone tools and other artefacts in northern Australia. According to traditional thinking, early members of our species, Homo sapiens, were just beginning to venture out of Africa at this time.
To get from Africa to Australia, H. sapiens would also have needed to march across mainland Asia, then sail across the sea. The route should have included a stopover on the islands of Indonesia and Timor, but no H. sapiens artefacts older than 45,000 years had been found on these islands, until now. ...
The team took another look at two teeth dug up by Dutch archaeologist Eugène Dubois in Lida Ajer cave on the Indonesian island of Sumatra in the late 19th century. Partly through comparisons with orangutan fossils found nearby, they confirmed the teeth belong to our species – and using a modern dating technique known as electron spin resonance dating, they dated them between 63,000 and 73,000 years old. ...
But the archaeology hints that the first members of our species to reach Sumatra faced a tough life. They may have been present in Sumatra when the island’s now-dormant supervolcano – Toba – gave rise to one of Earth’s biggest known eruptions, perhaps about 71,000 years ago according to recent estimates. ...
It's what'll happen when odd points of evidence appear all over the shop. Fossils are rare, in comparison with the number of live creatures of the type that existed, as are non-fossilised remains. It's amazing we have anything really and the more they look, the more they'll find. Every time they find a new data point, they'll have to redraw the graph, figuratively speaking.But anomalies continue to crop up. There may not be just one linear narrative.
The Gunk on Old Teeth Could Help Scientists Map Ancient Migrations
Having traveled so far back in time using ancient tartar, some of the same scientists have embarked on a more ambitious project: using the DNA from the bacteria in tartar to figure out how humans settled the 10 million square miles of Polynesia.
Polynesia has confounded the traditional ways of tracing human migration—archaeology, linguistic analyses, even human DNA—because large parts of it were settled so fast. Humans first reached the Society Islands, in the center of the Polynesian Triangle, perhaps around 1,000 AD. Then in the span of just a couple hundred years, they took canoes across vast tracts of open ocean to find specks of inhabitable rock as far-flung as Hawaii, New Zealand, and Easter Island. How Polynesians navigated these waters in the 11th century is a subject of considerable fascination. But even more basically, archaeologists are not sure exactly when the islands were settled and in what order. That’s where the tartar comes in.
Looking at genetics, some scientists claim that they hsve found evidence for another, earlier migration out of Africa. Though they say that first wave had little genetic influence.
http://www.bbc.com/news/science-environment-37408014
Modern humans left Africa much earlier
Researchers have identified the remains of the earliest known modern humans to have left Africa.
New dating of fossils from Israel indicates that our species (Homo sapiens) lived outside Africa around 185,000 years ago, some 80,000 years earlier than the previous evidence.
Details appear in the journal Science.
In the wake of additional analyses, it appears there's now a major shift in the presumptive timeline ...
SOURCE: http://www.bbc.com/news/science-environment-42817323
A study of Neanderthals suggests that “organized, knowledgeable and caring healthcare is not unique to our species”
Over 40,000 years ago a Neanderthal male — let’s call him Neanderthal Joe — between the ages of 25 and 40 suffered from a myriad of health issues in his last year of life, including a degenerative disease in the spine and shoulders and temporomandibular joint arthritis (TMJ). In prehistoric times, when hunting and foraging were key to survival, this would have put Neanderthal Joe in a vulnerable position, as the degenerative disease likely caused him to weaken in his arms and shoulders.
The common stereotype of Neanderthal would have you believe that this group of hominids were untamed, dumb, and perhaps even violent — an assumption that might lead you to assume that, in the situation above, his tribe might have seen an ailing Neanderthal Joe as a weight on their collective survival. However, articulated remains reveal that Neanderthal Joe was part of his community until his very last breath, according to a University of York study — published in the peer-reviewed journal Taylor & Francis. It appears he even received direct support from his community, such as hygiene maintenance and fever management, for of his many health problems.
In the fascinating study, researchers argue that medical care was an integral part of Neanderthals’ lives, and the motivation to take care of each other was likely driven by compassion and empathy.
“There is no reason to assume the healthcare practices in Neanderthals were driven by the necessity of a life that was unusually harsh rather than being a caring social and cultural response to illness, injury and vulnerability,” researchers say.
A new study suggests that early humans mated with the mysterious Denisovans in two separate waves.'
Around 41,000 years ago, a young woman died in a cold cave, high up in Siberia’s Altai Mountains. Scientists uncovered one of her pinky bones in 2008. From it, they extracted her DNA. And from that, they deduced that she belonged to a previously unknown group of ancient hominin, whom they called the Denisovans after the cave where the finger was found.
To this date, we have no idea what a Denisovan looked like. You can still hold every known Denisovan fossil—that pinky, a toe, and two teeth—in your hand. But we know so much else about them. We know almost every letter of their genome. We know that they diverged from their close relatives, the Neanderthals, around 400,000 years ago, and that both groups diverged from Homo sapiens around 600,000 years ago. We know that when our ancestors left Africa and spread into Asia, they encountered the Denisovans and had sex with them. We know that, as a result, Denisovan DNA lives on in people from Asia and Melanesia. One of these Denisovan genes provides modern Tibetans with a crucial adaptation that allows them to survive at high altitudes.
And now, thanks to work from Sharon Browning at the University of Washington, we know that Denisovan DNA entered the human gene pool on two occasions. Two separate groups of our horny, globe-trotting ancestors met with these mysterious hominins, and mated with them.
Browning developed a technique that compares the genomes of many modern people, and looks for stretches of DNA that are unusually varied, relative to their neighboring segments. These varied stretches are likely to have been inherited from ancient hominins like Neanderthals, Denisovans, or as-yet-undiscovered groups. Browning can then compare these segments to the genomes of those ancient hominins to work out exactly which group the DNA came from.
Some West Africans Have DNA Not Linked To Any Known Human Ancestor
According to findings, there is DNA from an unknown species of ancient hominin in about eight percent of the genetic ancestry from the West African Yoruba population. Because this DNA hasn’t yet been linked to a known ancient population, it’s being called a “ghost” species.
The question now is who does this “ghost” DNA belong to?
A hypothesis is that this DNA comes from a species known as homo heidelbergensis. There is evidence that suggests this advanced hominin population was living in Africa over 200,000 years ago. However, the DNA can also belong to a population of hominins whose existence up until now hasn’t been recognized.
There is less of the mysterious archaic ancestry found in the Yoruba population in selectively constrained regions of the genome. This finding suggests that the newly discovered admixture went through the same kind of filtering out process that previous Neanderthal and Denisovan admixtures went through, which resulted in the removal out of non-beneficial traits.
On the flip side, several results found that the archaic DNA sequence amongst this population was elevated in certain areas. This could be indicative not only of an impact that this archaic DNA has on modern Yoruba populations, but can also provide insight into how modern humans as a whole evolved as a species.
http://allthatsinteresting.com/west-africans-unknown-dna
Of course - it could be Ancient Aliens mixing it up with the locals... :embryo:
I think there are many extinct branches of the human family tree still to be discovered.
A fair few of the fossils being in land which is now under the sea.
More on finds in the Denisova Cave.
40,000-year-old bracelet made by extinct human species found
In what is quite an amazing discovery, scientists have confirmed that a bracelet found in Siberia is 40,000 years old. This makes it the oldest piece of jewelry ever discovered, and archeologists have been taken aback by the level of its sophistication.
The bracelet was discovered in a site called the Denisova Cave in Siberia, close to Russia's border with China and Mongolia. It was found next to the bones of extinct animals, such as the wooly mammoth, and other artifacts dating back 125,000 years.
The cave is named after the Denisovan people — a mysterious species of hominins from the Homo genus, who are genetically different from both Homo sapiens and Neanderthals.
We know that the Denisovans migrated out of Africa sometime after the first wave of Homo erectus, and well before us, Homo sapiens.
The Denisovans were unique in many ways, having branched away from other humanoid ancestors some 1 million years ago. Indeed, the recent discovery of a female Denisovan finger bone and various teeth shows that they had no morphological similarities to either Neanderthals or modern humans.
However, tens of thousands of years later, and prior to becoming extinct, they did coexist with us and the Neanderthals for a period, and skeletal remains of hybrids, and genetic studies confirm that they also mated with our forebears and the Neanderthals.
Strangely, however, DNA evidence also suggests that, at some point, the Denisovans must have interbred with an as yet unknown and undiscovered species of humans beings.
Skeletal remains show that the Denisovans were probably far more robust and powerful than modern humans, and were, until now, assumed to be a more primitive, archaic type of humans than us.
But, the discovery of the bracelet suggests this was far from true. Amazingly, the skill involved in making this adornment shows a level of technique at least 30,000 years ahead of its time. ...
Read more: http://www.digitaljournal.com/scien...ecies-discovered/article/432798#ixzz4h99Ow99y