“We’ve found a most remarkable creature”
September 10, 2015 5:30 AM   Subscribe

This Face Changes the Human Story. But How? This is the story of one of the greatest fossil discoveries of the past half century, and of what it might mean for our understanding of human evolution.
posted by ladybird (82 comments total) 68 users marked this as a favorite
 
"Wanna call it burial? If we found them in any human context, anywhere, you would. We have no better hypothesis."

A good follow on twitter for analysis and links to other responses is @edyong209
posted by cnanderson at 5:53 AM on September 10, 2015 [1 favorite]


That is pretty spectacular. Good post!
posted by Too-Ticky at 5:57 AM on September 10, 2015 [1 favorite]


Separated at birth. (Alternatively.)
posted by IndigoJones at 6:13 AM on September 10, 2015


HOLY SHIIIIIIIT THIS IS INCREDIBLE THE FPP UNDERSELLS THIS WILDLY
posted by Greg Nog at 6:22 AM on September 10, 2015 [19 favorites]


I wonder if they might have died in the cave, possibly individually, over centuries, due to suffocation or whatever.
posted by Joe in Australia at 6:22 AM on September 10, 2015 [3 favorites]


Berger is a tireless fund-raiser and a master at enthralling a public audience. But he didn’t have the bones.

also i like that this sounds like broseph is an extremely charismatic blob of gelatin
posted by Greg Nog at 6:31 AM on September 10, 2015 [13 favorites]


I can't help but wonder how well these type of stories will go over with National Geographic's new masters at Fox.
posted by sardonyx at 6:36 AM on September 10, 2015 [13 favorites]


Those cave descriptions always make me shudder. 8 inches of clearance? nope nope nope nope
posted by Theta States at 6:38 AM on September 10, 2015 [16 favorites]


Pretty neat that this broke in a journal that seems to be primarily online and interested in working around the rigid publishing ceremonies you hear about academic stuff.
posted by ignignokt at 6:39 AM on September 10, 2015 [1 favorite]


This find is amazing. Listening on the radio this morning I was convinced it was a burial site. I can't wait to find out the age of these remains.
posted by blurker at 6:45 AM on September 10, 2015 [1 favorite]


That diagram showing a cross-section of the cave they had to navigate is terrifying.
posted by straight at 6:48 AM on September 10, 2015 [14 favorites]


I love how this story has an "Assemble the team!" montage like an action movie.
posted by XMLicious at 6:49 AM on September 10, 2015 [9 favorites]


I love how this story has an "Assemble the team!" montage like an action movie.

I love that it specifically required small skinny people without fear

i imagine Berger sitting in a huge chair with tented fingers and rumbling to his assistant: "BRING ME... THE TWEEN SCIENCE GANG"
posted by Greg Nog at 6:51 AM on September 10, 2015 [46 favorites]


I wonder if they might have died in the cave, possibly individually, over centuries, due to suffocation or whatever.

Or getting lost in the dark.
posted by leotrotsky at 6:52 AM on September 10, 2015


Considering that elephants also honor their dead, the astonishment that primitive ancestors might do so "even with their tiny brains" seems a bit misplaced. Crows also have tiny brains but remarkable intelligence.
posted by emjaybee at 6:59 AM on September 10, 2015 [9 favorites]


I can't help but wonder how well these type of stories will go over with National Geographic's new masters at Fox.

It's aliens, man. It's aliens all the way down.

Pretty neat that this broke in a journal that seems to be primarily online and interested in working around the rigid publishing ceremonies you hear about academic stuff.

Yes, for some value of "neat." Dunno, I'm not a paleo-anything, but my takeaway here is more "maverick paleoanthropologist with a theory to prove rapidly excavates an enormous cache of undated (and possibly undateable) bones, assembles them hurriedly, and declares himself vindicated."
posted by octobersurprise at 7:01 AM on September 10, 2015 [1 favorite]


One of my friends from my graduate program is a "tiny caver" on this project, so I can't make my own post ... but I can comment! I'm not a paleoanthropologist, just a regular old anthropologist, and I haven't had time yet to read much beyond popular coverage, but I am very excited about how complete this find is, and can't wait for the American Association of Physical Anthropologists meetings in April. The Homo and Australopithecus sessions are always the most contentious and entertaining (full of infighting and arguments about tiny details of single bones and egos), and this one, I am sure, will be even more fun to watch! They're doing a lot of great open source science stuff, too, and really encouraging early career (and women!) scientists and broad interdisciplinary, collaborative research - which is a fantastic change from the way paleoanthropology is often done.

- Ed Yong's article on this is the best popular distillation that I've found: 6 Tiny Cavers, 15 Odd Skeletons, and 1 Amazing New Species of Ancient Human

- Berger et al. 2015. Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa. eLife Sciences. This one is the actual article describing the anatomy and morphology of the fossils - and it's open access, so look away!

- Dirks et al. 2015. Geological and taphonomic context for the new hominin species Homo naledi from the Dinaledi Chamber, South Africa. eLife Sciences. This article is all about the context of the fossils - the taphonomy (how the bones got there and what has happened to them, basically) and geology of the site.

- PBS Documentary which will be available online sometime today: Dawn of Humanity.
NOVA and National Geographic present exclusive access to a unique discovery of ancient remains. Located in an almost inaccessible chamber deep in a South African cave, the site required recruiting a special team of experts slender enough to wriggle down a vertical, pitch-dark, seven-inch-wide passage. Most fossil discoveries of human relatives consist of just a handful of bones. But down in this hidden chamber, the team uncovered an unprecedented trove—so far, over 1,500 bones—with the potential to rewrite the story of our origins. They may help fill in a crucial gap in the fossil record and tell us how Homo, the first member of the human family, emerged from ape-like ancestors like the famous Lucy. But how did hundreds of bones end up in the remote chamber? The experts are considering every mind-boggling possibility. Join NOVA on the treacherous descent into this cave of spectacular and enigmatic finds, and discover their startling implications for the saga of what made us human.
- Building the Face of a Newly Found Ancestor

- NY Times coverage

- The Times' coverage (South African paper)

- BBC coverage

- NPR coverage

- Lots of Twitter chatter from the anthropology community, particularly on #NalediFossils, #Homonaledi, and #almosthuman. You can also read @leerberger and @johnhawks, who were both intimately involved with the project.
posted by ChuraChura at 7:05 AM on September 10, 2015 [114 favorites]


OctoberSurprise, I would suggest that that is an incorrect take. Lee Berger's been very lucky with paleo finds previously (Australopithecus sediba was a pretty big deal) and this research is very much integrated within the broader paleoanthropological community. You can't do everything all at once - I know people want to know dates on these fossils pretty badly - but this is a really impressive achievement!
posted by ChuraChura at 7:07 AM on September 10, 2015 [10 favorites]


I was refreshing, looking for ChuraChura to weigh in. Worth it.
posted by cnanderson at 7:16 AM on September 10, 2015 [3 favorites]


I would suggest that that is an incorrect take.

Possibly. I'll admit that my initial response is conditioned as much by the breathless tone of the NatGeo story as anything else right now. And I'm not a paleoanthropologist, so I don't need to have a strong opinion either way. I'm content to be skeptically fascinated by all this and come back in a decade to see what shakes out.
posted by octobersurprise at 7:20 AM on September 10, 2015 [1 favorite]


This is so exciting. I am no paleontologist, or anything like it, but even as just a person who has watched a million episodes of Nova (et al) this is pretty world-shaking. To have it happen within such a cohesive narrative, and in basically central casting's idealized version of what a secret treasure cave would be? Astonishing. A nearly perfect mix of concrete facts and (seemingly) unanswerable questions. AND that one of the prime people involved in this was also instrumental in a previous blockbuster find - it's nearly mind-boggling.

“Five years went by and we sat in the lab having won the lottery and not going out into the field,” says Berger. “So I say: Buy another ticket. Because it appears that the odds are not that bad.
posted by dirtdirt at 7:31 AM on September 10, 2015


It's clever of PBS to time the related Nova episode (and to show it online before it actually airs) to coincide with the announcement...has Nova ever done that before?
posted by Esteemed Offendi at 7:51 AM on September 10, 2015


Mystery science theater, and the name of the cave means, star.

I like they have 15 complete skeletons. They can note the modern feet, long legs, curved fingers, across several whole individuals. What an amazing find.
posted by Oyéah at 7:52 AM on September 10, 2015 [1 favorite]


I'm sorry if people feel this post doesn't do the news justice, but I genuinely thought the NatGeo piece was fascinating, accessible for the layperson and that it provided a lot of additional content beyond just the article itself. I knew (and hoped) that researchers would weigh in with personal and academic perspectives but I certainly didn't intend to steal anyone's thunder or diminish the significance of the find. Thanks ChuraChura for providing more context!
posted by ladybird at 7:53 AM on September 10, 2015 [12 favorites]


Oh - it's not 15 complete skeletons, but material from 15 individuals. Which is still amazing - that lets you look at variation within populations in a way that you really can't do with most other Hominin species.

If you're interested in more current paleoanthropology, the European Society for the study of Human Evolution is meeting right now and presenting all sorts of cool data - lots of people livetweeting talks at #ESHE2015.
posted by ChuraChura at 7:56 AM on September 10, 2015 [5 favorites]


I'm sorry if people feel this post doesn't do the news justice, but I genuinely thought the NatGeo piece was fascinating, accessible for the layperson and that it provided a lot of additional content beyond just the article itself....posted by ladybird at 10:53 AM on September 10

You have nothing to apologize for - this is breathtaking find and the Nat Geo article is enough to get the conversation started.

Thank you for sharing. This was a wonderful read!
posted by glaucon at 7:56 AM on September 10, 2015 [11 favorites]


Oh, I'm sorry, I didn't mean that as a diss, ladybird; I think the article was great, and I'm super glad you shared it! I apologize for sounding like I was denigrating it. I'm just overwhelmed by how cool it all is, and hope more mefites click through on your FPP!
posted by Greg Nog at 7:57 AM on September 10, 2015 [2 favorites]


No big deal guys, and no apologies needed Greg Nog! I don't want to further derail the actual discussion which is indeed super cool.
posted by ladybird at 8:02 AM on September 10, 2015 [1 favorite]


A question - which maybe is already answered elsewhere in the links but I've missed it - that was raised in the Atlantic piece ChuraChura linked to: these bones have apparently not yet been aged. Is that in process?

This is so cool.
posted by rtha at 8:23 AM on September 10, 2015 [1 favorite]


I can't help but wonder how well these type of stories will go over with National Geographic's new masters at Fox.

National Geographic Society discovers ancient human who rewrites history, makes him majority shareholder.
posted by rory at 8:25 AM on September 10, 2015 [10 favorites]


An amazing find—I heard about it on the radio this morning and was delighted to find this here; thanks for the post!

Is there no way to date the bones? If there is, why haven't they already used it??
posted by languagehat at 9:20 AM on September 10, 2015


My understanding, languagehat, is that the bones themselves can't be dated - they'd normally use radiocarbon dating on the rock or material they were found within . . . but they're just sitting in some mixed sediment, so that method doesn't work. Not sure how they WILL do it, eventually.
posted by gorbichov at 9:35 AM on September 10, 2015 [2 favorites]


I wonder if they might have died in the cave, possibly individually, over centuries, due to suffocation or whatever.

Or getting lost in the dark.


Or banishment....
posted by EmpressCallipygos at 9:41 AM on September 10, 2015


I wonder if they might have died in the cave, possibly individually, over centuries, due to suffocation or whatever.

Dirks et al. (see ChuraChura's link above) consider that possibility - they can't conclusively rule it out, but it seems less likely than burial. In fact, they consider five possibilities, which they rank from least likely to most likely, in their estimation (see the "Depositional scenarios for the burial of H. naledi" section); the possibility that they died there, either individually or en masse, is judged to be the second-most likely of the five they consider.
posted by DevilsAdvocate at 9:43 AM on September 10, 2015


Radiocarbon dating only has an effective range of ~50,000 years. This material is likely much older than that so it's not really useful. Fossils this old are typically aged by dating the sediment or geologic layer they are contained within. In this case it's particularly difficult owning to the nature of cave deposits.
posted by wollaston at 9:45 AM on September 10, 2015 [4 favorites]


I wonder if they might have died in the cave, possibly individually, over centuries, due to suffocation or whatever.

The problem, at least to me, with this theory is that the bones are all in a VERY small space, in an otherwise well explored cave system. I'd think that if it was just a bunch of lost individuals they'd end up in other spots in the cave as well, and at least one have been found before now.
posted by Gygesringtone at 9:46 AM on September 10, 2015 [2 favorites]


You generally date the rock around the fossil deposits rather than the bones. These are too old for radiocarbon dating, so they'd likely use Potassium Argon dating which operates on the same principle, but has a much longer half life so can be used for much older material. Usually, what you'd really like to have is volcanic deposits immediately above and below the fossils (that's what you do in East African hominin sites). For caves, that is challenging and it's not immediately clear how they'll be doing the dating.
posted by ChuraChura at 9:48 AM on September 10, 2015 [7 favorites]


Berger himself thinks the right metaphor for human evolution, instead of a tree branching from a single root, is a braided stream: a river that divides into channels, only to merge again downstream.

This, to me, is the best take-away for the popular audience at this time. The changes we have seen in the modern Homo sapiens/Neanderthal narrative in recent years (a narrative shaped by a pretty sizable physical record)--a growing belief in the idea of co-existing populations that were capable of interbreeding--seem to be just as plausible in the earlier phases of the emergence of humans where the gaps in the record are so much larger.

In some ways the new hominin from Rising Star was even closer to modern humans than Homo erectus is.
I'm skimming the article and can't seem to find the specifics to what traits the article is referring to here, and I'm quite curious to know what they are.
posted by drlith at 9:55 AM on September 10, 2015 [2 favorites]


Ah! Wicked cool! Morphosource has some 3-D files of specimens you can download and play with if you want to see for yourself.

Drlith - it seems like the takeaway message in the Berger et al. paper (at least regarding phylogeny) is "The similarities of H. naledi to earlier members of Homo, including H. habilis, H. rudolfensis, and H. erectus, suggest that this species may be rooted within the initial origin and diversification of our genus" rather than "This is a closer ancestor than Homo erectus. I wonder if that's over-interpretation on the part of the National Geographic author?
posted by ChuraChura at 10:12 AM on September 10, 2015 [5 favorites]


In the absence of stratigraphic or other indirect evidence, dating is going to be very difficult. This paper from 2006 (PDF) discusses methods of direct dating of hominid fossils,and gives a variety of ways that can go back to around 300,000 years, but I don't know how much things have advanced since then. Given that there seems to be at least the possibility that the specimens may be as recent as around 100,000 years old, that would be a useful upper boundary for the dates even if it didn't give a result.

Perhaps there may be a way to tie in isotopic analysis of the teeth, which can show diet, with known climatic conditions at a particular time, perhaps linked to dating from the stalactites and stalagmites which are in the cave. There may well be DNA. Plus, there's a lot of stuff still to be found down there; they ran out of time, not bones. But I'm arm-waving.

Exciting times.
posted by Devonian at 11:24 AM on September 10, 2015 [5 favorites]


So I'm not familiar with this site and haven't read the article, but to add to the already good comments above re why dating will be difficult - cave stratigraphy is hard:
Putting it simply, cave sediments are generally not always the easiest of deposits to comprehend, since the correct conditions for the preservation of chronologically deposited layers are often absent.
Unfortunately, this also makes tephrochronology a non-starter, since it's using layers of volcanic ash (even those undetectable to the unaided eye) as a chronostratigraphic marker horizon, and if the stratigraphy isn't secure, any inferences based on a method relying on intact stratigraphy are right out.

I can see this while not logged in, so hopefully others can also? It's Grün et al. 2010, 'The challenge of direct dating old human fossils', which I have not (as far as I can recall atm) read, but it's a recentish paper by reliable authors. Possibly something more recent floating around, though.

In case it is of interest.
posted by you must supply a verb at 12:23 PM on September 10, 2015 [7 favorites]


Berger himself thinks the right metaphor for human evolution, instead of a tree branching from a single root, is a braided stream: a river that divides into channels, only to merge again downstream.

Not to mention, of course, the theory that the braided stream included some dalliances with pigs.
(previously on the blue).

And yes, Fox would love that part.
posted by rongorongo at 12:46 PM on September 10, 2015 [1 favorite]


Ack. Sorry. More or less duplicated the link from Devonian, sorry!
posted by you must supply a verb at 12:46 PM on September 10, 2015




Pretty fascinating! It's really hard to see as anything but deliberate burial. If they were just disposing of bodies on instinct to keep them from drawing predators, they'd just dump them down the entranceway, not pass through two very tight passages in the dark to do it. And even the outer, larger cave doesn't seem to have any easy entrances, so seems an unlikely place for inhabitants (ie, unlikely that people living in the big cave used the smaller one as a deposit for bodies-as-trash). Plus you'd also think you'd find other remains of hunting carcasses put there. And the fact that they found complete bone assemblies throughout the cave suggests that at least some of it wasn't even dumping, it was careful laying out of bodies. It's hard to read it as anything but them treating the bodies of their dead as something very special and worth great effort to place in a certain location. Which suggests either the ritual of it or the location had some kind of deep meaning for them, some kind of spiritual belief.

So I guess my questions are...

- how'd they find it in the first place? Crawling around in caves seems a dangerous occupation, and while they were small and the passages might have been wider before flowstone build up, it doesn't look like it was ever easy. Looking for water, maybe? You'd have to be pretty desperate, but it's an area with seasonal rains and droughts, I could see them being that.
- how'd they light their way, or did they? I know use of fire goes back a million years or more, but making torches that will last to light your way through that complex and deep a cave seem a higher level of technology than just keeping a bonfire going.
posted by tavella at 1:23 PM on September 10, 2015


I thought The Atlantic said fifteen complete skeletons, infant, elderly, adults, a good cross section. The teeth in one of the images, so perfect.
posted by Oyéah at 1:52 PM on September 10, 2015


Has a cause of death been determined for any of the remains? I've been thinking about how they'd get bodies in there, and it doesn't sound easy even considering that these hominids were much smaller than we are and the cave passages could have been larger.

So then I thought: what if they went into that chamber alive? That would have huge social implications. But I'm no scientist, just another avid reader of the Simplified For Liberal Arts write-ups.
posted by cmyk at 2:17 PM on September 10, 2015 [2 favorites]


They don't seem to have been violently killed (I think there was one long bone with evidence of a healed break, but not cutting or tooth marks), and the age distribution - young, old, not much in between - matches what you'd expect from a cemetery deposit.

From the brain size and the many non-human characteristics, it would be expected that they wouldn't have been developed enough for the sort of social system that buried the dead, let alone complex ritual. But the deposit has all the hallmarks of a burial.

So, nobody knows. This find has created many more questions than answers.
posted by Devonian at 2:34 PM on September 10, 2015 [4 favorites]


By the sound of the access point, it implies that someone had to drag the body into the secluded portion of the cave - which I find fascinating. There's so many potential ideas behind such an activity, be it simply wanting them not feasted upon by carrion feeders or the place itself having some honored purpose. It makes me wonder if they'll find any tools or anything left with the dead to indicate an idea of a need in the afterlife or not. That'd blow my mind.
posted by Atreides at 3:36 PM on September 10, 2015


My friend Jacqueline snagged an interview with Gurche.

For the record, John Gurche is the paleoartist who did the recreations for the model busts and paintings and such, not the subject hominid.
posted by Lemurrhea at 4:14 PM on September 10, 2015 [2 favorites]


ancient monkey ancient monkey dying in a cave ancient monkey
posted by poffin boffin at 4:16 PM on September 10, 2015 [6 favorites]


Thank you, Devonian. This is so fascinating. Even if we'll never know the true reason those bodies were placed in that cave, the speculation offers so many interesting ideas - and says a lot about those of us doing the speculating, too.
posted by cmyk at 4:25 PM on September 10, 2015


Is this really a new species? I think that question is up for debate, and the answer will depend on whether you are a "lumper" or a "splitter."

The really amazing thing is the MNI. There are not 15 complete skeletons, but rather skeletal elements representing 15 unique individuals. This is an almost unheard of find with probably the exception of Atapuerca. So, yes this is an amazing find, but the particular claims being made by the PI and NG are not really a consensus position at this point.

Also, it seems a bit tenuous to be making any claims at all about where these remains fit into our understanding of the genus homo with out a firm date.
posted by AElfwine Evenstar at 9:08 PM on September 10, 2015


But the deposit has all the hallmarks of a burial.

Not necessarily, we can imagine a collapse and re-deposition. There are no grave goods and/or ceremonial paraphernalia. What we have is at best a disturbed primary deposit, but much more likely a secondary deposit. You have to remember that this depositional environment is by its nature constrained so if there was a collapse senario with a secondary deposition this is about what we would expect. I have to read the geology paper in more depth to get a better idea of the geology and taphonomy, but my initial feeling is that claims of burial are going to have to meet a higher standard of proof than what I've seen so far.
posted by AElfwine Evenstar at 9:25 PM on September 10, 2015


As far as dating they should be able to do uranium series dating if the fossil layer is contiguous with or abutting any calcite deposits.
posted by AElfwine Evenstar at 9:32 PM on September 10, 2015 [1 favorite]


Maybe they were taken down by a huge snake, and digested, rather than devoured, leaving their bones mostly intact.
posted by Oyéah at 9:46 PM on September 10, 2015


Actually, Aelfwine, Churachura's link pretty conclusively shows it isn't redeposition, for multiple reasons. Notably, delicate assemblages like hands are still intact and perfectly articulated, not jumbled; the geology of the cave doesn't allow for flooding; the bones show no signs of the type of wear and damage you would expect from being thrown around in a flood; the bones are almost entirely human, with only a tiny handful of rodent and other scavenger-type bones, not the wide variety of animals you would expect from a random redeposit; and and the rock around the cave is solid, with no sign there was ever any other entrance or any pit that could have collapsed. So whatever this is, it is not a case of bones being gathered and redeposited by natural forces.
posted by tavella at 9:47 PM on September 10, 2015 [10 favorites]


This is amazing, but perhaps my favorite bit is the part where a bunch of people said 'so, you're looking for extremely petite women to fly to a foreign country and explore a mysterious skeleton cave? Seems legit.'
posted by nonasuch at 9:55 PM on September 10, 2015 [7 favorites]


Just in case anyone else was wondering: difference between hominid and hominin
posted by crocomancer at 4:35 AM on September 11, 2015 [2 favorites]


TURN BACK NOW! IT'S ACTUALLY THE BONES OF THE PRIOR EXPEDITION THAT HAD BEEN MUTATED BY THE CAVE AND KILLED BY THE TINY WALKERS INSIDE THE WALLS!
posted by Theta States at 6:57 AM on September 11, 2015 [3 favorites]


That ruled out [...] prehistoric serial killers
Good to know.
posted by jeather at 7:17 AM on September 11, 2015 [1 favorite]


This is amazing, but perhaps my favorite bit is the part where a bunch of people said 'so, you're looking for extremely petite women to fly to a foreign country and explore a mysterious skeleton cave? Seems legit.'


If you're not kicking yourself for already doing this as an opening for a horror screenplay that subverts the whole Fay Ray character in King Kong by making these women the kickass heroines, you are not me.
posted by MCMikeNamara at 8:09 AM on September 11, 2015 [3 favorites]


> The problem, at least to me, with this theory is that the bones are all in a VERY small space, in an otherwise well explored cave system. I'd think that if it was just a bunch of lost individuals they'd end up in other spots in the cave as well, and at least one have been found before now.

This is probably just the speculations of the zeitgeist in which I'm immersed, but is this burial theory really indicating an early form of culture, or could it be that this collection of bodies is the work of ...a single obsessed individual?

He may have walked upright...
(•_•)
( •_•)>⌐■-■
(⌐■_■)
... but he wasn't an upright citizen. Could we have on our hands the coldest of cold serial-killer cases?

(We can never know, of course, until I get the kinks worked out on my time-tunnel.)
posted by Sunburnt at 9:45 AM on September 11, 2015 [1 favorite]


Eyewitness News South Africa put together a really amazing website about the Rising Star Caves, and Homo naledi - the coolest part is a 3D scanner video of going through the cave system to the fossils.
posted by ChuraChura at 10:14 AM on September 11, 2015 [12 favorites]


emjaybee: "Considering that elephants also honor their dead, the astonishment that primitive ancestors might do so "even with their tiny brains" seems a bit misplaced."

I was just chatting with ChuraChura about this, and it's such a pre-Darwinian holdover of wanting a clear, bright demarcation between humans and animals. Even lots of people who fully accept evolution are eager for a clear, distinguishing characteristic that makes us different and unique.

Me, I find it far more comforting that while our skills may be unique in degree, they're not unique in kind -- other animals honor their dead, other animals "talk," other animals use tools. It would seem sad and lonely to me if we were an alien thing on the face of the earth cut off from all other animals who have ever arisen. But a lot of people find it very anxiety-inducing if there's not one clear skill or tool or specialization that makes us human.
posted by Eyebrows McGee at 11:58 AM on September 11, 2015 [18 favorites]


Science Friday had a great segment on this today.
posted by futz at 4:00 PM on September 11, 2015


Even lots of people who fully accept evolution are eager for a clear, distinguishing characteristic that makes us different and unique.

we have Taco Bell, none of the low animals got that
posted by Greg Nog at 4:51 PM on September 11, 2015 [2 favorites]


Rats and roaches can get Taco Bell any time they want.
posted by rtha at 4:58 PM on September 11, 2015 [9 favorites]


Science Friday had a great segment on this today.

Yeah, Lee Berger said that there are many more remains still in the cave and also hinted that they have at least two different localities with what he called "discoveries."

Churachura's link pretty conclusively shows it isn't redeposition

After reading over the geology paper that seems to be pretty conclusive. There also seems to be calcite deposits in what they are calling flowstone 2 directly above the fossil layers as seen here (G) and here. Unfortunately:

Flowstone samples from the Dinaledi Chamber were analysed for uranium to assess the possibility of U-Pb dating. Although analysed samples mostly contain sufficient U for this (0.3–0.7 ppm), a fine dusting of a detrital component derived from associated muds is present in all tested pilot samples. This has confounded preliminary attempts at U-Pb dating, because of the high, and isotopically variable, background of common Pb it carries.

So I guess we may have to wait a while for a firm date on the site.
posted by AElfwine Evenstar at 9:15 PM on September 11, 2015


My preferred theory is still "they climbed in, but couldn't climb out."

The paper's argument against this is that the bodies represent a mix of ages, without the over-representation of young males that you might expect if the bodies were those of explorers. I'm not sure if I accept that: young males would be the ones most likely to escape, and the burial hypothesis actually requires that the hominids could enter and leave freely, in the dark, perhaps even without language to allow transmission of information about the cave. This is not necessarily the case, even for gracile individuals like the ones represented among the remains.

The bodies were very possibly deposited over hundreds or thousands of years. Perhaps some of the remains were explorers, others may have been fleeing dangers or hiding. If we presume that entrance and exit was difficult - a very plausible assumption! - then it would only take one fatality every hundred years or so to supply the remains we have found.
posted by Joe in Australia at 3:31 AM on September 12, 2015


the burial hypothesis actually requires that the hominids could enter and leave freely, in the dark, perhaps even without language to allow transmission of information about the cave. This is not necessarily the case, even for gracile individuals like the ones represented among the remains.

The burial theory:

The researchers don’t argue that these much more primitive hominins navigated Superman’s Crawl and the harrowing shark-mouth chute while dragging corpses behind them—that would go beyond improbable to incredible. Maybe back then Superman’s Crawl was wide enough to be walkable, and maybe the hominins simply dropped their burden into the chute without climbing down themselves.
posted by Greg Nog at 6:29 AM on September 12, 2015 [1 favorite]


How fortunate for human knowledge that anthropology's legendary hostility towards women wasn't enough to keep these six scientists out of the field. This is phenomenal.
posted by KathrynT at 10:55 AM on September 12, 2015


KathrynT, I confess that when I read "Berger put the word out on Facebook [...] He chose the six most qualified; all were young women", I thought "Cripes. It's Louis Leakey all over again."
posted by Joe in Australia at 5:53 PM on September 12, 2015


Another thought about "how'd they get in there through such a small passageway" - do we know that the passageway was always that small?
posted by EmpressCallipygos at 8:18 PM on September 12, 2015


Joe in Australia: The bodies were very possibly deposited over hundreds or thousands of years. Perhaps some of the remains were explorers, others may have been fleeing dangers or hiding. If we presume that entrance and exit was difficult - a very plausible assumption! - then it would only take one fatality every hundred years or so to supply the remains we have found.

What has been found was only from the surface (~300) and a 0.8 x 0.8 m pit that was ~20 cm deep around the skull (~1250). That may have been the richest area, but there are still many more fossils in the cave that could represent more individuals. Also of note is that fifteen individuals is a minimum.

The paper also notes that "Significantly, no examples of spiral (green) fractures have been documented, which indicates that post-depositional processes are the primary agents of skeletal damage." If these individuals ended up stuck in the cave I'd expect there to be significant injuries.

But the conclusion of the section on deposition scenarios is "Both the mass mortality or death trap scenario (although possibly not involving a single event) and deliberate disposal hypothesis are considered plausible interpretations and require additional investigation. Based on current evidence, our preferred explanation for the accumulation of H. naledi fossils in the Dinaledi Chamber is deliberate body disposal, in which bodies of the individuals found in the cave would either have entered the chamber, or were dropped through an entrance similar to, if not the same as, the one presently used to enter the Dinaledi Chamber."

So they seem to think that death trap is a possibility too.
posted by mountmccabe at 9:02 PM on September 12, 2015


One thing just occurred to me: if the remains are the result of deliberate burial, surely they would include individuals that died from trauma? I appreciate that it may be too early to tell one way or another, but I think that would be a good indication: if bodies are found with limbs removed by predators, it's pretty clear that they didn't climb in by themselves.
posted by Joe in Australia at 9:08 PM on September 12, 2015


From the paper: "Despite abundant fossil material available for taphonomic study, we have, thus far, found no trace of carnivore damage on the Dinaledi remains." And, again, they claim "post-depositional processes are the primary agents of skeletal damage."

But, huh. Deliberate burial with no trauma victims, to me would have to mean significant selection of the individuals buried here. It'll be really fascinating to see what the experts come up with, what evidence they find.


I just watched the Nova Dawn of Humanity episode mentioned above and found it really fascinating. It shocks me that people saw those cave crevices and decided to go further, but wow, it was really great to see inside the caves, and see what it took to get these fossils out.
posted by mountmccabe at 11:22 PM on September 12, 2015 [2 favorites]




After having a week or so to talk to other people in the field and read over the articles in depth it seems that homo Naledi is most probably H. erectus. Also, there has been a lot of exasperation among the paleoanthopologists I've talked to about going to press after barely year and a half without a date. Also, important is that the current assemblage only contains one adult cranium with the rest being juvenile which are very problematic for defining a species type.

So yes there's probably a middle ground between the year and a half for Naledi, and the 16 years Tim White took to publish Ar. ramidus. Either way it seems that for the most part the paleoanthropological community is thrilled by the richness of the find, but not so much about how Berger et al have gone about creating a media firestorm without doing their due diligence.
posted by AElfwine Evenstar at 7:45 AM on September 16, 2015 [3 favorites]


Well, here's John Hawks' response (in part):
Homo naledi has a mosaic of features that include some that compare most closely to more primitive australopiths, and others that compare more closely to Homo. How do we know that this is one species rather than a jumble of species mixed together? Simple: every feature that is repeated in the sample is nearly identical in all individuals that preserve it. It would be very strange to have a mix of different species where all seven proximal femora come from one species, while all of a dozen lower third premolars come from a different species...

How are we to know that Homo naledi is not the same as a primitive, small Homo erectus? Well, for one thing, at least two H. naledi individuals have endocranial volumes around 460 cc, much smaller than any H. erectus cranium ever found. There is barely any overlap between the larger individuals and H. erectus, with only a single H. erectus specimen coming close to the H. naledi range of variation in volume...

When we look at the postcranial skeleton, there is simply no way that H. naledi could be confused for H. erectus. H. naledi has a long, anteroposteriorally flattened and anteverted femur neck, which looks very different from African and Dmanisi femora attributed to H. erectus. The H. naledi tibia is exceptionally mediolaterally thin and long, with a rounded anterior border and tubercle for the pes anserinus tendon, all traits that we could not find in known tibiae attributed to H. erectus including Dmanisi. The H. naledi scapula has a superiorly oriented glenoid, very different from the Dmanisi scapula specimen or the Nariokotome H. erectus skeleton. The vertebrae of H. naledi do not match in proportions or morphology the comparable examples from Nariokotome or Dmanisi, and the pelvis of H. naledi exhibits a short, flared ilium unlike those known for H. erectus, including the Gona pelvic specimen.

It’s just a poor match to H. erectus, so that the only way to make the H. naledi fossils fit within Homo erectus is to stretch that species beyond any other ever defined in the human lineage. There are clearly some similarities, which to us indicate something about the evolutionary relationships of H. naledi and H. erectus—but we are hesitant to go so far as to posit a unique relationship of these two species because many of their similarities also overlap with species such as H. habilis, H. rudolfensis, and even Australopithecus sediba. Figuring out those relationships will take additional research and analysis.
posted by ChuraChura at 12:49 PM on September 21, 2015 [5 favorites]


Here's the Gona pelvis that he references: A Female Homo erectus Pelvis
from Gona, Ethiopia

posted by AElfwine Evenstar at 11:55 PM on September 21, 2015 [1 favorite]


Race, South Africa, and Homo naledi:
A day after the announcement [of Homo naledi], Zwelinzima Vavi (former general secretary of COSATU) tweeted: “I am no grandchild of any ape, monkey or baboon – finish en klaar” (Afrikaans for “that’s it”). Of course, for many South Africans, this sentiment is understandable. White South Africans have international reputations for their racism, and it is not unusual for racist slurs to include comparisons with apes or monkeys. In fact, Vavi also tweets: “I been also called a baboon all my life so did my father and his fathers.”

It is with that knowledge, that it becomes difficult to laugh off Vavi’s statement as mere ignorance, or religious influence. And then there’s all the “other stuff”: racist comments on online news platforms, comparisons of (black) politicians with our newly discovered relative by cartoonists, the painfully obvious paleness of many of the researchers involved in the research and the announcement… Indeed, it is an unfortunate coincidence that many of these politicians targeted by cartoonists and memes are black, but within a context where many black South Africans have been, at one point in their lives, debased or ridiculed in such a manner, this entire situation becomes a lot more sensitive.
posted by ChuraChura at 10:42 AM on September 22, 2015 [1 favorite]


« Older A shaggy dog story   |   Super Glitchy Mario World Newer »


This thread has been archived and is closed to new comments