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 Post subject: New early humanoid species?
PostPosted: Thu Sep 10, 2015 10:57 am 
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Regardless of whether or not this find represents a new species on the evolution scale, this is an incredible discovery. So many bones and so many examples, we should hear about it for decades to come.

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 Post subject: Re: New early humanoid species?
PostPosted: Fri Sep 11, 2015 7:30 pm 
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This is exciting news.

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 Post subject: Re: New early humanoid species?
PostPosted: Sat Sep 12, 2015 9:40 am 
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They found two fingers and a tooth and declared the denisovans a new speicies, yet with all these full skeletons they're not quite sure if the naledi are a new species or not. Kind of funny to me.


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 Post subject: Re: New early humanoid species?
PostPosted: Sat Sep 12, 2015 9:03 pm 
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Drakens wrote:
They found two fingers and a tooth and declared the denisovans a new speicies, yet with all these full skeletons they're not quite sure if the naledi are a new species or not. Kind of funny to me.



Denisovans aren't a new species yet.

Somebody would have to publish a paper in a peer-reviewed journal with a formal species description, and no one has done that yet. The problem is that it's known Denisovan DNA is different from both H. sapiens and Neandertals, but there isn't enough skeletal material to determine if they are H. heidelbergensis or something else. (For that matter, it isn't clear if H. heidelbergensis itself is a valid species). Nobody wants to publish until this is ironed out; what it would take is finding enough skeletal material to establish that the specimen was H. heidelbergensis, then find preserved DNA from that skeleton, then sequence it and compare it to Denisovan DNA. Right now I think there's a partial DNA sequence from skeletal material from Spain assigned to H. heidelbergensis that's "similar" to Denisovan DNA but nobody has come down on one side or the other yet. AFAIK it's not possible to name a new species based on DNA alone, although that might change. It is possible to describe a new species based on a photograph or even a drawing, which has led to some interesting results:

http://www.nature.com/nature/journal/v2 ... 8466a0.pdf


H. naledi has received a formal description as of 09/10/2015 and is therefore now a valid species unless demonstrated otherwise:

http://elifesciences.org/content/4/e09560


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 Post subject: Re: New early humanoid species?
PostPosted: Wed Sep 23, 2015 9:25 pm 
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Nature 17 September 2015
News in Focus
Crowdsourcing digs up an ancient human species
A more detailed account of the discovery of Homo naledi than has turned up in the MSM. In 2013, South African paleoanthropologist Lee Berger "learned of" (the article doesn't say how) a small underground chamber loaded with early human fossils. His approach was a social media post asking for volunteers who were small, skinny, nonclaustrophobic, physically fit and with caving experience. Access to the Naledi chamber required a "Superman crawl" - so called because to get through the 20cm wide passage you had to extend one arm forward like Superman did when he was flying in the old comics (the actual bone chamber was larger, but Berger has never seen it; he can't make the crawl to get there). He got six volunteers to get the specimens out. Berger then sent out a second social media call, this time asking for scientists "at the start of their careers" to analyze the fossils and got 30 responses.

The social media approach created a stir in the field; nobody said anything directly but Berger's colleague John Hawks said "There's a lot in the field who really believed we're just a couple of cowboys who don't know how things should be done". (As an aside, I wonder when "cowboys" became a pejorative in this sense? The people I know who would qualify as "cowboys" are way more able to "get things done" than just about anybody else I know).

The specimens belong to at least 15 different individuals, and there are hundreds of individual fossils. There are still some major mysteries, the most prominent being how did the fossils get there? Other cave deposits are places where things fell in through a sinkhole, places where animals were washed in by flood water, or places where carnivores denned up with their captures. Naledi doesn't match any of these; tellingly, there are practically no other bones in the chamber (a couple of rodents and an owl) except H. naledi. The suggestion being tentatively broached is this is a deliberate burial. As of this time, the specimens haven't been dated; the most anybody will say is "very old".


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 Post subject: Re: New early humanoid species?
PostPosted: Wed Feb 24, 2016 9:13 pm 
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Scientific American March 2016
Mystery Human
A popular account of the Homo naledi site. The most interesting thing to me was the tentative speculation on how the bones got there. Getting to the fossil chamber requires going through the "Superman Crawl" - a passage so narrow that it can only be negotiated with one arm stretched out in front, like Superman; climbing the Dragon's Back, 12 meters of jagged rack, then dropping back down through a near-vertical chute 20 centimeters wide and 12 meters long. Once in the fossil chamber, over 1550 bones and bone fragments representing every age group from infant to geriatric have been excavated from "an area the size of a card table" - and there are apparently a lot more waiting.

Except for a few mice and owl bones, they're all H. naledi. There's no sign of predators that could have carried them in. The stratigraphy doesn't show any flood deposits, so they weren't washed in. There's no evidence that the passages were wider in the past. The inference, then, is that something of approximately Homo erectus brain capacity deliberately dragged deceased members of its species through these narrow passages - in pitch darkness, unless fire was invented early than suspected - and left them there.

There are other possibilities but none stand out. Maybe there was an especially tidy and highly specialized predator - but there's no report that any of the bones show signs of predation. Maybe they were alive when they entered the fossil chamber - i.e., it was a place you went to die (but that wouldn't explain the infants). Maybe it was a place you went to be killed - but the bones, again, don't show any sign of trauma. Maybe a more advanced human species did it - but that still raises the question of why they would. Perhaps as more excavation is done some explanation will turn up.


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 Post subject: Re: New early humanoid species?
PostPosted: Wed Feb 24, 2016 11:08 pm 
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The most interesting thing to me was the tentative speculation on how the bones got there.

That drives me nuts! I'm watching a couple of old British series on YouTube just now, and one of their discoveries (Windypits, Yorkshire) was in caves where only an experienced caver dared to go down to see where they were found - there were narrow slides and jagged rocks overhead, up and down, leading to the chamber. :shock: I guess there could have been another entryway at some point, or wider passageways (thought of and discarded in your post) or something, but an equally interesting thought, to me, is how on earth did someone find them? (Yes, I do go and look it up.)

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 Post subject: Re: New early humanoid species?
PostPosted: Tue Jun 28, 2016 9:31 pm 
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American Scientist July-August 2016
Spotlight
The Latest on Homo naledi
Still rather mysterious. The skeletal material shows a a number of modern human adaptations. The feet indicate an upright gait; the hands and fingers were capable of precision grip and therefore tool-making; but the shoulders and ribcage are more characteristic of a climbing species, and the cranial capacity is smaller than even Homo habilis; it's in the australopithecine range. There's still nothing that can be dated and the best explanation for how the bones got where they are is still they are from bodies that were carried in.


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 Post subject: Re: New early humanoid species?
PostPosted: Tue May 09, 2017 11:49 am 
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Three new papers on H. naledi published today. A second cave was found with the remains, again, of what appears to be the dead of the tribe. And the dating indicates MUCH more recent activity than originally thought.

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