- welcome everyone towednesday nite @ the lab. i'm tom zinnen. i work here at the uw-madisonbiotechnology center. i also work for uw-extension,cooperative extension, and on behalf of those folksand our other co-organizers, the wisconsinalumni association, wisconsin public television and the uw-madisonscience alliance, thanks again for coming towednesday nite @ the lab.
we do this every wednesdaynight, 50 times a year. back on september10th of last year, i had the pleasure ofgoing to give a talk at the biotechnology class atthe verona area high school. it had happened that thenews of the discovery of a new hominin, homo naledi,had broken just that morning. the uw had played keyroles in characterizing and describing this new species, so i asked thestudents at verona
about their take on that story. they're only about 12 milesfrom this rather remarkable public land grantresearch university. i wanted to get an idea of what they hadgleaned from the media. there was one girl in theclass, she was a little shy, but she sure seemed toknow a lot about that work. and i asked her how sheknew so much about it. and she said, "well,john hawks is my dad."
(audience laughs) and she was prettyproud about that. it's a great delight to getto welcome back john hawks. this is at least thethird time he's been here. he is the vilas-borghesi distinguished achievementprofessor of anthropology. and we get to hear tonight about one of hisfinest achievements. it's a story that has alreadybecome a point of pride
for the universityof wisconsin-madison. but professor hawks has aneven more splendid achievement: he has made his daughterproud of her dad. please join me inwelcoming john hawks back towednesday nite @ the lab. (applause) - wow! thank you everybodyfor coming out tonight. i see some familiarfaces out there.
i see a lot of facesi haven't seen before. i'm so pleased that all ofyou have come in to hear about this work that we'redoing here at the university and in collaboration with ourcolleagues in south africa. it's really exciting stuff. and this is just the firstphase of the research. tom told you aboutmy daughter sophie. she is the only, to myknowledge, high school girl who's actually helped to packmaterials for homo naledi
in the vault in southafrica where they are. so, you know, she had a ringsideseat during the workshop when we weredescribing this stuff. i'll say a coupleof words about it and how we came to involve so many people inthis description. but it has beenreally special for me to be a part of it fromthe very beginning. it's been an enormous privilege
to be working on this projectat the rising star cave because our work withnational geographic, which comes through ourproject director, lee berger, he's a national geographicexplorer in residence, has enabled us to havea lot of media resources on site from the very beginning. and actually my project hereat the university of wisconsin, developing the massiveopen online course, we delivered that twoyears ago now this spring
to 40,000 peoplearound the world. and that was being organized at the time thatthis project began. so we actually had a lot of university of wisconsinvideo resources on hand. so we have a uniquedocumentation of the project actually fromthe very point of discovery. and that's a greatprivilege for me because i have the resourcesto be able to show you
some of these thingsin people's own words, so that you cansee what's going on at the site as we're excavating. and the first thing i'dlike to show is a word from one of the caverswho was responsible for the initial discoveryof the bones in the cave. he gives you afirst-hand account of how they came todiscover these bones. - caving has always been great.
caving, you want toanswer the question of what's aroundthe next corner. that's always thequestion you want to know. it's mostly fueled by curiosity. but as you get intocaving more and more, the scientific sideof it comes into it. you want to know, howdid these places form? what happened heremillions of years ago? what happened herebillions of years ago?
basically, itcreates a fascination with this whole environment. in my wildest dreams iwould never have thought that caving would take me towhat's happening here. (laughs) you could almost callthis a bit of an accident. so, my cavingbuddy and me, rick, we were off exploring thiscave on a friday night. we'd gone into a veryremote section of the cave, a part that i hadnever been in before.
and in that section, westumbled upon fossils. (laughs) yeah, at first, we didn'texactly know what fossils yet. we started lookingaround a bit more until we found a mandible. and that's when we knewthis was probably hominid. that was when we gotexcited about it. (laughs) and since this discovery, it's (laughs) crazywhat's happening here.
pedro boshoff is a geologist. he's been caving in thiscountry for 50-plus years. and he was asked bylee to basically goand look for fossils in deep sort of areas of caves. and he'd then spoken to myself and rick and a fewothers and said he needs us to come startlooking for hominids. (laughs) and on this whole expedition, he has been incharge of the cavers,
coordinating who is hereand what we have to do and getting everythingorganized for us. and since the startof this expedition, from the cavers' sidewe've been putting in over two kilometers of cabling. those are forcameras and lights, communications within the cave. and we've also putup safety ropes straight throughout the cave,
for the safety ofthe scientists, making sure there's no injuries. and we're here for backup. in case something does go wrong, we are here to assistas soon as possible. - this is lee berger, who'sthe director of the project. these guys were interestedin working with lee potentially because leehad been responsible for the discovery of a fossilnamed australopithecus sediba.
that discoveryhappened in 2008-2009 and those resultshave been published over the last six years. they got a lot ofattention as creating a new process of discovery where people wereexploring new caves. and lee had gone over the ground across the entireworld heritage site, it's called the cradle ofhumankind world heritage site,
mapping caves that hadn'tbeen previously mapped. so these guys whowork underground, it's their hobby to gointo caves on the weekends and try to push the boundaries, go into parts of caveswhere they didn't know that anybody hadever been before. and they said, "sometimes wesee bones when we do this. "maybe we can work with you "and we might findsomething too."
and of course lee said,"that's wonderful!" i've talked to himabout it many times. he did not expectthat the first cave that they went into we wouldmake a massive discovery. and yet it was his philosophy that when you're going tostart something systematically, you go into your backyard first. go to the places that you know. and the rising star cave, whichis underneath this hillside,
which is pretty nondescript, this hillside is basicallya chert dolomite hillside, and inside of it aremore than a kilometer of underground passageways that make up the risingstar cave system. this is a small partof the system map that shows you the area thatwe're actually working in, from our entrance to the chamber where we found themassive fossil deposit.
in this kilometer ofunderground passageways, are lots of twisty-turny routes. and you get intothem really quickly after you go into the cave. how many of you folkshave been in a cave? how many of youhave been in a cave? been in a cave, yeah.okay, brilliant. how many of youhave been in a cave where you have to crawl onyour hands and knees somewhere?
okay. and how many of you haveactually had to squeeze so that rock was againstyour front and back? yeah. this, if you haven't done it, can be a reallyterrifying experience. if you're claustrophobic at all, this is a realproblem situation. but this is the situation thatthe rising star cave poses.
and it's why our cavers like it. because you can getinto those kinds of really hairy placesright after the entrance. so, you don't have to spendall day caving underground to get somewherereally interesting. and it's a greatplace to bring people to train them onthat kind of caving. so, people were reallyfamiliar with this cave, and it's been known inthe caving community
for more than 50 years. it lies less thana mile-and-a-half from at least six veryfamous fossil sites, including two that have beeninvestigated systematically for more than 70 yearsfor hominin fossils. so, it's in a veryfossil-rich environ. but fossils had never beennoticed in this cave before. the reason why probably is thatthese really narrow passages and twists and turns make it
really hard toaccess these bones. so, when you saw these guyssort of squeezing through that super narrow place, the way that we reachthe dinaledi chamber, where we are nowexcavating fossil hominins, is by going downa vertical drop. you can see it there onthe edge of the graph. the dinaledi chamber ison the far right side. and there's thisvertical little drop
that is about a12-meter vertical decent that has a minimum width in it of about seven-and-a-halfinches, 18 centimeters. so in order to get down that, you have to have theclimbing ability to do it. and steve, who you sawtalking there in the video, when he initially foundthis, the reason why is that he had climbedup this dragons back, which is this ridge of rock-fall
that has come downin the distant past. and so you have to climb it,and you get up to the top of it and there this little narrowsort of, i don't know, entryway that you cansort of hang out in. and he had wedged himselfdown in this crack to rest, and he noticed that hedidn't touch the bottom. and so he did exactlywhat your or i would have done inthe same situation. he said, "i wonderwhat's down there?"
(cables swooshing) and he went down 12 meters, and rick followed him. so, that was how thediscovery was made. this was not anobvious place to look. it was very difficult to reach. and that created immediatelya problem for our team. how are we gonnaexcavate in this place? once they had broughtthe photos out,
and they knocked onlee's door late at night. and they said, "you'regoing to want to let us in." and he looked at the photos.he's like, "this is a hominin." and he sent me the photos. he sent it to a numberof our senior colleagues who've been involvedin the project before. he said, "what doyou think of these?" it's a fossil hominin.there it is. it's a jaw bone layingon the floor of a chamber
that clearly isa fossil hominin. not a human, butsome earlier form, and all the bones that yousaw there to go with it. so, it was clear that wehad to mobilize immediately. well, lee didexactly what you or i he put a call on facebook. "dear colleagues: i need thehelp of the whole community "and for you toreach out to as many "related professionalgroups as possible.
"we need perhaps threeor four individuals "with excellentarchaeological, paleontological "and excavation skillsfor a short term project "that may last themonth of november "if things go as planned. "the catch is this: theperson must be skinny "and preferably small. "they must not beclaustrophobic. "they must be fit, they shouldhave some caving experience,
"climbing experiencewould be a bonus." within a few days lee hadreceived 57 applications from qualified peopleall around the world. and on a basis oflooking at their records, interviewing them over skype, he selected sixoutstanding young women to be the caving team thatwould be the people responsible for excavating in thisvery challenging place. and so, here's our team.
and i'd like to point out second from the leftthere is alia gurtov, who's a university ofwisconsin graduate student, part of ouranthropology program. on the far leftis becca peixotto, who is involved in outward bound and a master'sstudent in archeology, now a doctoral studentat american university. elen feuerriegel is fromaustralia national university.
marina elliott, inthe right center, is now directingfield exploration in the cradle for the project. she was at simon fraseruniversity in canada. lindsay eaves. and hannah morris, now atthe university of georgia. so our caving undergroundteam, outstanding young women. and over the course of lessthan three weeks underground, they excavated what would be
the largest singlefossil excavation ever conducted in africafor hominin fossils. so, i'll show you some scenesof the underground work, it's a challenging situation. everything that you see usworking with underground had to be taken throughthose narrow passages. and that means thepower, the lights, the computers, thescanners that we use. you see them workingthere in very closed off,
sort of contortingsort of circumstances. it became really rapidly clear after very little excavation. this is me in the cave, right. and i put this uphere to remind myself to tell you guys howworthless i actually am. i don't fit. i will never set foot in theplace where these fossils are. lee will never setfoot in that place.
this is a very special chamberthat you can only access with the right climbingand caving skills and the right physical makeup. and most people don't have it. it has been a greatprivilege to be involved in the project inthe way that i have. and i like to tellpeople, especially kids, the cool thing about thisis, i'm never gonna be there. and the only way that i knowwhat i do about this place,
and i know as muchabout this place as anyone else inthe world right now, the only way that iknow anything about it is by doing science on it. and that's pretty cool. we, throughout the project, compared what we were doingunderground to astronauts. because it is sort of like,i mean, they're not in space. but it's sort oflike a spacewalk.
because when they'reworking in there, we cannot get to them. it took a half an hour for ourteam to get from the surface into the chamber tobe ready to work, and a half an hour foranything to come back out. so they're really quite remote. and my view from uphere on the surface, from the tents above ground is entirely virtual.
so here's lee looking at oneof our virtual viewpoints. we have cameras underground. and basically this is our view. we're watching theexcavation in progress. and we can help tounderstand what's going on. we can give some expertguidance about what to do. but honestly, it'sup to our team to do the best work thatthey can underground, under some verychallenging circumstances.
so, i mean, there issomething mesmerizing about watchingthis happen, right? because you seeher working there with a little plastic spoon. hannah's working in thebackground with a little brush. this is standardarcheological equipment. and what a lot of peopleare surprised about with the rising star assemblage, is that unlike many fossilsites in southern africa,
our fossils are notembedded in a hard rock. most fossil sitesthat we work with, the bones are imbedded in arock that we call breccia, which is made upof bone, gravel, stuff from outside thecave that's fallen in and glued together with calcite,so that it's a hard cement. our bone is in a soft sediment that's basically like avery fine-grained clay. and to work in it we justhave to brush it away.
the challenge is that ourbones are incredible fragile. and i'll say some morewords about that later. these bones are nothardened into rock. they are incredibly fragile. and so we come to challenges. now, when we looked at thephotographs from the cave, all of us pored overthose photographs before we started excavation. and we said,
"you know, i don't seeanything here that's repeated. "this looks like it's gonnabe one hominin skeleton. "i don't see anyparts doubled here." and that would be anamazing discovery, right? because when you think aboutthe most famous discoveries in my field that have everbeen made, things like lucy, lucy is a skeleton that'sabout 40% complete, and that is one of the mostimportant single pieces of evidence of ourevolutionary history.
we expected thatwe were gonna find something about that scale. and, of course, that was gonnabe tremendously important. we would have probablyfor the first time a skeleton associatedfrom an individual of a south african species that we probablyalready knew about. something likeaustralopithecus robustus, which is found onlya half-mile away,
at the site of swartkrans. so, this seemed very likely. it was gonna tell us somethingthat we already knew, but in much better detail and would give usa first ever look at the whole anatomyof something. and that was gonnabe really exciting. that feeling lasteduntil the first day that we sent ourteam into the cave.
our first day, we goteverything arranged. we set up everything doto a run into the cave to make sure thatthe equipment worked, to bring out one bone. we targeted thatjawbone and we said, "okay, let's make this happen." the jawbone cameout and all of us who were on the seniorpart of the team, who knew the anatomy ofall these fossil hominins
like our own children,i've got to tell you, looked at thejawbone and we said, "that's not whati thought it was." the next day our teamwent to work seriously bringing bone out of thesurface of the chamber and brought up three piecesof right thigh bones, all of differentright thigh bones. it was suddenlyclear, immediately, that we were lookingat multiple skeletons.
this was not the kind ofsite we thought it was. suddenly, this wasvastly more important than we suspected it was. and so to give you an ideaof what that was like-- - today we're workingon extracting a skull. - i'll show you a day at work. - it's looking to be fairlydifficult at the moment because the skullis very pliable. it's very, very soft, 'causeit's quite damp down there.
it's adding to the problem. so, i think, at the moment,our current strategy is to try and remove theskull in one giant block. as much as we can, anyway, because there's a lotof underlying bones. we've got two people working ondifferent sides of the skull. so, i think you've got more eyes on what the actualskull is doing as we're trying to excavate it.
- we are very hopeful that theycan get it out in one piece. there's a good chancethat they will. but if they cannot,at least we'll have it very carefully exposedand we'll be able to very carefullydraw and indicate where exactly eachpiece came from. and then we'll deal withit in the science end. we can watch theirwork very carefully, and that's been very helpful
for us to understand whatthey're seeing down there. the coolest thing is thati can't get down there, but it is as closeas anyone can get to being there to help them. (machinery rumbling) - [voiceover] hi! - it's early evening,late, late afternoon. it's time forfossils to come up. - well, they're supposedlybringing it out right now.
- if it's lying on itsside--(sound obscured by wind). it'd be really nice. - it feels completely surreal. this just doesn't happen. they're coming to begin up. so, if somebody wants todo this, now is the moment. - [voiceover] it'sa big moment again! every time it's a big moment. - is that it?
all right. - look at that. here it comes. - [voiceover] there it is. - let's go get it. (people laughing) - we got the large sectionof the cranium out. glad to be done with that part. there's a lot more down there.
there's a wholepuzzle of long bones, and other bones, down,underneath where that was. about halfway through the time marina and i were downthere, it was pretty clear that we weren't gonnaleave 'til it came out. there was no waywe were stopping. the science tentclosed a while ago, and they have something tokeep 'em busy in the morning. so, that's good.(laughs)
- we began digging at thatspot because of that skull. we cleared the surfaceof the chamber. there were bones scatteredon the surface as you saw. we were collectingthose from the surface. but there was this skullprotruding from the dirt. and so we began workingon that to extract it. as our team beganworking around it, they discovered that the skull is actually sitting upon bones.
and those bones are laidlike pick-up sticks, one on top of the other, asfar down as we could sense. and so this became amassive undertaking, just working toget that skull out. and once it was out, workingon and gradually exposing more and more ofthis layer of bone that was making up the chamber. every bone that we were finding, there was a bone ofa fossil hominin.
and they were in exceptionalcompleteness in many cases. so suddenly thiswas an undertaking that we were working literally, probably centimeters a day, just clearing outwardand making sure that we were very carefullyexposing the bones, and then safelybringing them out. everything that came out ofthe cave had to be marked, catalogued on thesite, photographed,
put into secure watertight bags, put into a waterproofpadded caving bag and had to come outthat narrow passageway. so, it was enormouslystressful, let's say, that we had to do allof this to make sure that everything came out safely. but it was alsoenormously elating every time something wouldcome out of the cave. because every time weopened up one of these
there was thepossibility, and most, i mean, more than half the time, it was something thatnobody had ever seen before. so, including bones thatwe almost never find at fossil sites, you know? so, i'll show you someof these bones in a bit. it is really quite aremarkable achievement. but as a result, thatsituation of the fossils posed some veryspecial challenges.
for one thing, weworked for 21 days in this site, excavatingan area that is smaller than the area of this table. less than a squaremeter, and to a depth of less than a fourthof a square meter throughout most of it, less that a fourth ofa meter, excuse me. so less than a foot deep,across less than a square yard. this is an amazing assemblageto come out of that space.
most of the bone assemblagein the cave is still there. we have excavated only avery tiny fraction of it. also, the uniquesituation of the cave, the cramped situation, the inability to getstraight sight lines and the densepacking of the bone, meant that we needed to study the spatial arrangement of this in a different waythan we usually do.
usually, we can setup surveying equipment and very precisely getin the points of things by setting up a station. in our case, wecouldn't do that. we needed to use adifferent approach. and the approach that weused was a scanning approach. here you'll see the resultsof some of our first scans. we have a scanner thatwe can take the surface of the excavationat every point.
and, in fact, afterevery bone removal, we take the surfaceof the excavation so that we have layer by layer, everything that we'vedone in the site can be reconstructed justback the way that we made it. so, it is reallypushing the technology to enable us to reconstruct thearrangement of these things. we're already learning thingsabout the spatial arrangement that we wouldn't haverecovered otherwise.
one of the other things thatwe were doing on the site was we had our underground team. we had a team ofmore than 20 cavers that were involvedin the excavation, running cabling, as yousaw, keeping things safe. we had cavers in thecave at all times to make sure we could getthings out of the cave, and to get people outif it was necessary. all of these folks werecamping above ground.
and we needed to, a,allow people to recognize the importance ofwhat they were doing. so that if they were takingtime away from their families, from their jobs, theycould tell people, "hey, check this out." so, part of thereally great thing about our social media presence, tweeting from the site,doing facebook posts, getting nationalgeographic video
on youtube from the site, and here our team skypingout to schools from the site, we were skyping to schools andcountries all over the world, was that it enabled peopleto really get the sense of something reallyimportant that's happening. and it enabled us toshare as much as possible the process of thiswith the public. so while there were aspectsof it that we couldn't, we couldn't saybecause we didn't know.
we hadn't studied thebones yet scientifically. we could still tell peoplewhat the process was. "here's what we're doing.here's what we're finding. "yeah, we found another thighbone out of the cave today. "we found another mandible. "and here's how we're doing it. "here's how we'llstudy these things. "here's what wedon't know about it." that turned out to bea massive resource.
we reached out, in one ofour videos within 36 hours, it was seen by more than300,000 people around the world. so, this was really something that people werefollowing everywhere. the packing up on the site, it was clear that withthis assemblage of fossils, at the end of novembermore than 1,200 fossils. after another week ofexcavation in march, which we came back todo some targeted work
to bring out a couple of things that we knew were atthe bottom of this pit, but we hadn't been ableto get out safely before, we recovered another300 bone pieces. so, we had in all morethan 1,500 pieces of bone. we needed a very specialway to study that. that by itself is thelargest assemblage of fossil hominins everdiscovered in africa. there's only onesite in the world
that comes close to this,in terms of fossils. it's in spain and it's an earlyform of our own genus, homo. so, what we did was to get the wordout, again via facebook, again via social networks. we need people to come and helpus to analyze this material. if we just took theteam of senior people who've been involved in theproject for many years to come and describe stuff,it would take us
years and yearsand years to do it. we didn't want todo it that way. but we also wanted to takeadvantage of the opportunity to broaden theinvolvement of this to a new generation of people. so, we got the word out thatwe were looking for scientists who were in their early career. people who werefinishing their ph.d., who had alreadydone their research,
who already had data sets, or who had recentlyfinished their ph.d. they're in their firstposition, a post-doc, an assistant professorship,and you've got data sets, "please apply."tell us what you've got." and we have resourcesto bring people to work on the fossils. and that's exactly what we did. during june of 2014,may and june of 2014,
we assembled more than 35 early-career researchersin south africa, funded by the south africannational research foundation to do the primary descriptionand analysis of the fossils. this was an amazing time, i think for all ofthem, certainly for me. because, imagine, right? you've got peoplewho've been dreaming about doing this sort of thing
for at least what has beenin their careers to date. and i'll never forget,taking the big, these things are in a vaultlike a bank vault, right? with a giant door,and taking the big key and opening the vault anddoing the (door opening) and letting these folksinto the fossil vault for the first time andseeing these fossils. it was really quite amazing. and on site here formore than five weeks,
we put more than10,000 person hours into the analysisof these fossils. we measured them inevery way possible. we scanned them.we made surface models of them. we described them in relationto every fossil hominin that we had to compare them to. and that includednot only originals that exist in south africa,but high quality copies of things that we assembledby getting everybody
around the world whohad copies of things to send them to us so thatwe could compare them. so we really put togethera scientific document that shows theanatomy of something that would turn out tobe, after our analysis, a species that had beentotally unknown to us before. a new species thatwe named homo naledi. naledi in the sesotho language, which is one ofthe local languages
spoken in this area, means star. and we named it star becauseof the rising star cave that we found them in. and we named the chamberwhere we found the bones, the chamber that hadnot been on the map before our team went into it, we named that chamberthe dinaledi chamber, which means thechamber of stars. so homo naledi turned out to be
similar in some waysto early members of our own genus, genus homo. but also substantiallydifferent from them in some really interesting ways. it gave us a picture of aspecies that we didn't expect. this is a virtualmodel made from some of the scans of the bones, some of the 3-d scans. so this is a 3-dmanipulatable model.
here's is the bone layout, that shows you themultiple pieces of each part thatwe have preserved. for the first time, we wereable to prepare a description of a new species of homininbased on the entire skeleton. usually we find a jaw.and we compare that jaw. we pour over it, comparing itto everything we know about. and we find a few detailsthat make it different, and we say, "ah, thisis something new!"
in this case, we're able tocompare the entire skeleton. and some things really areunique, we've never seen before. and some things overlapwith other species. but what was key aboutthis was that the things that overlap with one species, other features wouldoverlap with something else. this was a newcombination of things that we'd never seen before. so the skull is themost charismatic part.
everybody loves the skull. we have parts of atleast five skulls, and very probably more. when i say at leastfive, what i mean is that i can show by laying them out that i have the samepart repeated five times. so, we have parts ofat least five skulls. we have parts of at least15 individuals' dentitions. i'll show you teeth in a bit.
here's our teamworking on the teeth, or on the skull, theseearly-career people. my friend davorkaradovcic on the right from the natural historymuseum of croatia. and here's one of the more complete skulls. this is dh-3,dinaledi hominin 3. this is the skullof an old woman. and i'll show you that tooth set
in comparison to the others. we know how old theyare from their teeth, if they preserve them. here's a couplemore of the skulls. here, i like to showhow much we have, right? here are all piecesof the brow ridge. here are pieces ofthe temporal bone, just in front of the ear. here are pieces of cheekbones.
here's the back of the skull. but, in addition to this,we can use our scans to virtually reconstruct things. and this gives us alot of information about the structureof these things. so, here's dh-3 from the front. and here's a reconstructionof what its endocast was like. the inside of itsbrain, of its skull, gives us some indication ofthe outside of its brain.
and that doesn't tell us a lotabout the function of the brain, but it does give us agreat idea of its size. these hominins hadbrains about a third the size of yours and mine. so, they're really quite small. and yet theirskull is structured very much like homo erectus, a species thattypically has brains about twice the size of this.
so, in structure, it's like amore advanced-looking thing. in size, it's like a moreprimitive-looking thing. and just a comparison,here's teeth on the x-axis versus brain size on the y-axis. our evolution tendsto follow a trend, where if you go from thelower right to the upper left, you're going actuallyforward in time. so, that australopithecus,our primitive ancestors, had large teethand small brains.
and as we go up closerand closer to us, through our genus, homo, you get smaller teethand bigger brains. so there's this sortof dual set of trends. homo naledi that you see there, the white bar, is smallteeth, small brain. and that's very atypical. that's not the kind ofrelation we expect to see. my friend john gurche,who's, in my mind,
the best artreconstructor of fossils, has done a reconstruction for us of what our mostcomplete skull, dh-1, would have looked like in life. so, that bust isbased on this skull. dh-2 is the skull thatyou saw them working on there in the cave that came upin, ultimately, a cereal bowl. that was the best thing for it. it laid upside-downin a cereal bowl
and we put it insideof that lunch box and it came up through the cave. and here's dh-1, the mostcomplete of the skulls. well, i'll say a fewwords about teeth because teeth we get alot of information out of. and we're still gettinginformation out of these teeth. we've done micro-ct scanning of all of the teethin the collection. and so we're now studying
the internal structureof the teeth. we will go on to studytheir development. so, we'll get some idea ofhow fast these individuals may have developed in theirlives by studying that way. we will also study theirisotopes to get some idea of what fraction of their diet may have come fromdifferent food sources. so, we'll get a lot ofinformation from these teeth. but for me, somebody who'sused to working on teeth
from other collectionsthat are large, the most exciting thing is, is that we can get apicture of what this group would've been likewhen it was alive. because here is an array of the more completeof the dentitions. this is six dentitionsrepresenting a range of ages. so that, at the upper left, we have a nearly complete setof teeth, upper and lower.
these are all baby teeth except for the verybottom ones there, in the upper-left set. those are the firstpermanent molars. this is a set ofteeth from a toddler around the age of two or three, if this was humanterms, in terms of age. probably they developed alittle faster than we do. so, probably a little younger.
at the bottom right, youhave the oldest individual. that individual has almostworn her teeth completely out, so that they're worn allthe way down to the roots. in fossil terms, that usuallymeans that this individual is somewhere in their mid-30s. so, if you think old, old, old, that's old, old,old for these folks. and we haveeverything in between. we have children.
we have at least eight children in the collectionof a range of ages. we have infants, includingone either newborn or near-term fetus. we have, we have young children. we have olderchildren, adolescents. and we have young adultsand one very old adult. so, this is a picture of thedemography of a population. we've never had that before.
not from one site like this. and certainly not from asprimitive a hominin as this is. so, this gives usunique information that we're only really startingto be able to work with. this is my favorite thingin the whole collection, because when you havea bunch of loose teeth that you've found in acave, fitting them together is like the greatestpuzzle ever. because there arebiological clues
about which teethgo together and how. and they leavetraces on each other so that you canactually discover, "ah! this tooth goes with this!" last month, i was there and we had a toothcome out of the cave because we had tosample another tooth for some datingmethods, and i said, "ah! i know exactlywhere this goes!
"i know whose tooth that is." the clues are there. so, this is my favorite, because it's this beautiful,beautiful condition dentition. this is the entireset of lower teeth and we have mostof the upper teeth as well of this individual,of what in human terms would be about anine- or ten-year-old. but we have not onlythe skull and the teeth,
which we often haveat other sites, we have the restof the skeleton. and we have lots andlots and lots of parts of the rest of the skeleton, including completearticulated parts. so, this in the site is theright hand of an individual. the fingers arebent over like this so that you see theintermediate phalanges, these middle parts of thefingers bent over like that.
this is what youcall a death pose. because here's the handand it's gone like this. and all of the bones are there. the only bone lackingfrom this hand is this little one in thewrist, the pisiform bone. if you fall on theice, don't do it, but if you do and you throwyour wrist down like this, this one you might breakor at least dislocate. so, it's there.
we don't have that bone. we have every other bone from every otherindividual, it's amazing. put this together andthis hand, by itself, and we have parts of many hands. we have 150 hand and wristelements in the collection. we have 190 teethin the collection. it is an amazing sample. but this hand itself hasthis mixture of features
that indicate different things. its wrist and itspalm is fundamentally a human wrist and palm. but its fingers are very curved relative to our fingers. its fingertips, you cansee them, the fingertips, they're broad at the end. a chimpanzee's fingertipsor the fingertips of some of our early ancestors
are very narrow at the end. that's because weuse our fingertips togrip things strongly when we're making andusing stone tools. you guys aren't makingor using stone tools but your fingers arestill well-made for it. and you gripstrongly, powerfully through your fingertipsbecause of it. these guys, we've never founda stone tool yet in our site. so, i can't say for surethat they were doing that,
but their hands aresure made for it. but those curved fingersmean that their hands were also well-made forgripping onto things like this and suspending weight from them. which tells us that theywere probably climbing. climbing a great deal, we think. but the one thing that'sweird about this hand that we've neverseen before anywhere is the bone that connects
the thumb to the wrist. that bone in thepalm of your hand that moves like this becauseit's a first metacarpal. and it's the one thatroots your thumb there. you can see that thisis a powerful thumb. but that bone in particular, the wrist end of that boneis at the bottom here. the thumb end ofthat is at the top. and this bone is totally wrong.
because you can see that itis thicker at the distal end, the thumb end, than itis at the wrist end. this is like apopeye thumb, right? he's got those massiveforearms and they're wrong. this is wrong. we've never seenanything else like this. but i love to show this slide, because sometimespeople will say, "well you foundsomething unique,
"that was probablyjust a weirdo. "that was probably justa strange individual." we've got seven of these! they're allmorphologically the same. they all have thisstrange character. and that tells usthat this is actually a characteristic of homo naledi. this is something about the way that it was adaptingto its environment
that gave it thisunique morphology. you can see the curvaturethere of those fingers. and the forearms, theupper limbs let's say, are actually really slender. you look at that humorous. i've printed it here. this is a really slender bone. and when we look atthe rest of the post, and we have juveniles ofmost of these as well.
so, we can look at thatdevelopmental aspect as well. this is an adult humorous. this is a juvenile humorous. and on both casesthe head of this, that connects to yourshoulder is broken off. but the distalend is there here, and just short of there here. so, this is the bone of probablya six- or seven-year-old and this is thebone of an adult.
these are little,slender, but long compared to how thin they are. and we're gonna seethat throughout. the shoulders of homo naledi, to make a long storyshort, are like this. they are oriented onthe body of homo naledi as if they're made toreach up and climb stuff. they are not oriented inthe way that ours are, which is fundamentallywith our scapulas down here
and to the side of our bodies, well made for winding up and throwing stuffor hitting stuff. homo naledis are madefor climbing stuff. and the clavicles match,these long, long collarbones. we've got lots of feet. my graduate student, myph.d. student i should say, who now is an anatomy professor at lincoln-memorialuniversity, zach throckmorton,
came from uw and isone of the experts working on the feetof homo naledi. we've got many partial feet, many of them also found inarticulation in the site. the most complete one shows afoot which, in zach's words, right, "this is as humanas yours and mine." it's got the archesthat our feet have. it's got the proportionsof the toes that ours do.
the lateral toes there, we havemost of the bones of those. but it's really hardwith little toe bones to know for sure which is which. so we don't show them inthe diagram like this. we've got them oriented there on the cover ofthe "on wisconsin." so you can see all the toebones, and one finger bone. it's not my fault. you see all the toe bones.
this is a toe that'smade for upright walking, bipedal striding, but in aessentially human-like way. it is a human foot. and that contrasts withthings like the shoulder, which is not likea human shoulder. the lower limb,here's the tibia. likewise, long and slender, and you start getting a picturefor how big those guys are. you can see that allthese bones are slender.
all these bones are skinny. whatever height they are, they seem like they'renot very thick. they're not massivefor their height. when we work with thesenumbers from the long bones, we estimate thatthese guys stand about four-and-a-halfto five feet tall. so they're human-sized. they're not big-human-sized
but they're the size ofsmall-bodied human populations. people like pygmies,like the khoisan people of south africa,yeah, south africa, like the andaman islanders. folks around the world whoare small-bodied populations, homo naledi is their size. again, juvenile tibiae. we've got at least eightadult proximal femora. i've got a bunch of themprinted here as well.
the femur is different fromthe rest of the hindlimb. the feet are human. the tibiae are long andslender, but basically human. the femur, acrossit, is mostly human. but you get to thatproximal femur, and the neck ofthat proximal femur, the part that connects toyour hip joint, is long. and i'll tell youexactly why that is... when we look at the hip...
which is flaredoutwards like this. and so if i take apiece of the hip, and the hip is a tragedy. my post-doc here,caroline van sickle, her specialty is the hip. and she workedwith us on the team that was working on the hips. some of you might havegone to her lecture when she did wednesdaynite @ the lab.
so, i always tell peoplethat the hip is a tragedy. and she's like,"why is it tragic?" well, it's tragicbecause we have, actually, a lot ofbroken pieces of it. and we get a lot ofanatomical clues from those. and i've just sent her to madrid where she's working withspecialists who've reconstructed what this hip might'velooked like from the pieces. but the first clue that we get
is that when weorient this properly, you see that is justflares outwards like this and the femur necksare long to match. this is a dynamicthat we see in some of the earliest bipedalhominins, the australopiths. it's a dynamic that showsthat they have great force to keep their bodies upright. they have very goodleverage for that. and they have alot of hip swing.
but it's not very human-like. we have a much morevertically-oriented hip. and ours are much better made for long-distancewalking and running. so, this is a veryprimitive confirmation to go with that veryhuman-like foot. and that's a bitof a puzzle for us. we haven't worked it out yet. so, when you look acrossthe whole body, homo naledi,
and this is john'sdrawing of this, and i think he's donejust a great job. on the very left, we have lucy. her species isaustralopithecus afarensis. it's one of the mostprimitive bipedal hominins. afarensis is small. lucy stood just a bitover three feet tall. next to her is themost complete skeleton of homo erectus, reconstructed.
this is a skeleton from kenya. it's called the stripling youth, or the boy from nariokotome. and people always rememberhow to say nariokotome because it's pronouncedlike frontal lobotomy. i will never forgetwhen i was taught that. so, now i'm transmitting it. and on the rightyou see homo naledi. homo naledi's inbetween these two
in stature, the size ofa small-bodied human. but i think john has done theshoulders especially well. he's done the thinness well. he's done the stance,i think, well. it is a very human-like stance. but it doesn'tlook quite like us. and that's what youget with homo naledi. we do not know how oldthe fossil assemblage is. we have excavated it froma very uncommon setting.
it does not have thebone embedded in rock. we do not have asclear of indicators of the antiquity of the bone. and you might say, "well,the bone's probably young." and that's a possibility. this bone could actually be relatively youngin fossil terms. that would still betens of thousands, hundreds of thousandsof years old,
but it might be verydifferent in age from other things in the area. but i have worked onhominin collections, dmanisi in the republicof georgia for instance, where the bone is twomillion years old nearly, but is also very fragile andnot embedded in hard rock. so we don't know for sure the age of thisfrom the condition. we are working inthe site to discover
the age of the fossilsby bracketing them with flow stone deposits. we have flowstones that areabove our fossil deposit. we're working to discover what is at the bottomof the fossil deposit. and the densityof bone means that we don't just dig rightthrough with a drill, right? so we actually have to bevery careful about this. and that is holding usup on determining a date.
but you can seethe possibilities. it is a very primitivemember of our genus. it's like maybe theearliest examples of homo erectus witha smaller brain. it's like homo habilis,a very primitive member of our genus, witha smaller brain but with more advanced aspects of the feet andhands, for instance. so, it looks like it'srooted in our family tree
around the time thatour genus originated, maybe two to two-and-a-halfmillion years ago, possibly earlier. but the fossils may bemuch younger than that. they could be that age, right? it could be, "wow!this is our ancestor." or it could be that thefossils have survived alongside other species thatevolved more similar to us. and we don't know.
so, when we drawthe family tree, you can say that homohere is the bottom branch, and these orange speciesare different kinds of homo. homo naledi is this green one. and maybe it's very recent. maybe it lived alongsideof even modern humans. that's a possibility. maybe it's the agewe think it is. it's even a possibilityit's much older
than it sort of ought to be. in which case it wouldestablish an earlier date for the origin of ourgenus than we thought. so, discovering the date takeson some primary importance in understandingwhat happened to lead to the evolution of humansand other species of homo. well as tom indicated, we had a lot of newswith this discovery. this is my photo on the newyork times, just wonderful.
the international attention tothis has been just enormous. it has been really,really great to see that our science has gottenthis kind of attention. this is the skull right? i'm the one who made away with the one the vicepresident kissed. this is the vicepresident of south africa who appeared at our announcement and was really nice about this.
i just, it is so neatto be in south africa, in many ways still adeveloping country, still investing inits strategic areas of scientific advantage. fossils, obviously, a huge area where they arepushing their science and to have, at the highestlevels of government that recognize theimportance of this. at our announcement,the vice president said,
"this work demonstratesthe scientific basis "for a common humanity." and that is what it does. this is showing our ancestry. the things that tie ustogether, historically, are things that came fromthese ancient species. and discovering how they lived is telling us aboutthat shared history that every humanaround the world has,
especially in countrieslike south africa where you have thishuge human diversity that has had a historyof great troubles. being able to contributeon the scientific side to showing the common humanityis incredibly important. of course, any timethere's a great discovery, you get in the comics. "fossils of new human species "found in africancave" is the headline.
"did we discover anextinct caveman too? "not quite." he's got the artifacts ofour political campaigns, trump has a club,donald was here. but in southafrica, this took on a really, sort ofmore spirited view. this was when the rugbyworld cup was happening. and as you can seehere homo naledi was ready to join theteam, the springboks.
if you guys have seen thatmovie with the springboks. it really is like that there.they're crazy for their rugby. and, it's neat to be, "this is the mostexperienced bok team ever, "with a millionyears between them." but when it comes down to it, we have just an enormousamount of work left to do. we've done as much, i think, as possible to getthis out to the public.
not only through ourparticipation in social media, but also here we putthe fossils on exhibit. for the first time ever,a new fossil discovery of hominins on exhibitfor the public. and record-breaking 10 timesthe ordinary visitation to the visitor center ofthe world heritage site to see these fossils. as you can see, school groups, people of all ages coming out.
it was just a unique thing. when they left they puton a farewell concert and they had someof the greatest acts in south africa on stageto salute homo naledi. it was really something. so, that was really special. but we've alsomade great strides in sharing the scientificresults more broadly. in paleoanthropology it is...
from my point of view, i've been in thefield for 20 years, from my point of view, sad that our studentscannot handle fossil casts from someof the most famous fossils in the world. you can't get acast of lucy now. you cannot get copiesof these fossils to show to your students.
we want to change that. we made our priority to share this information asbroadly as possible. we published our work inelife, an open access journal. and we put our fossilscans on the web so that anyonecan download them. we, to date, have hadnearly 10,000 downloads of these from around the world. and people are using those toprint out fossils everywhere.
i show up places to give a talk and they'll say,"here's our naledi!" it's amazing!(audience laughs) i've been printing them inmy lab like crazy, right? so, i've gotfossils to bring in. but for us the important thing is that this is a southafrican discovery. and so the chancellorof wits university, the university that hosts ourwork and hosts the fossils,
at our announcementsaid these words. and i think they'rereally important. because they show the way theworld of science is changing. "we often talk about scienceas having no boundaries, "but in our worldscientific knowledge "has become commodified,and too often, "what should be thebequest of the world, "the bequest of acommon humanity, "is locked up under pay wallsthat postgraduate students
"and researcherscannot get access to." we're at a tremendous advantage here at the universityof wisconsin because almost anythingthat i want to read, the library will get for me. this is not the casein most of the world. it is not the casein south africa. and so to be ableto do this work in south africa andgive it to the world.
as he said, "what we didwhen we made this discovery, "was we put thecameras in the cave, "we streamed it live. "we partnered with elife,an open access journal, "to make sure that the discovery "was available toall of humanity. "and what we didin that practice, "is create the first elementsof a common global academy. "we're not simply goingto be beneficiaries
"of open access, butwe are going to be "contributors to open access." this isn't africa comingwith its hands out looking for peopleto give stuff. this is africa providingthe best that it has to the rest of theworld as a bequest of a common humanity. and so, to be a part of thatproject, with that priority, for me, istremendously important.
you guys are gonna want to know,how did the bodies get in there? we have a very unique situation. a situation in whichwe have no other medium or large mammalsother than hominins. aside from the hominin bones, we have six piecesof a bird's leg and some teeth and a coupleof other bones from mice. and those mice teethand bones, we think, we're pretty confident, werethere before our hominins.
they're in a differentdeposit than our hominins. our hominins are therein what look like at least two differentdepositional events. the bird we thinkprobably came in later, 'cause it's on the surface, it's preserved differentlyfrom the hominin bone. that's what we got. this chamber is where it is. it is remote.
it's, for our team,very difficult to reach. we do not believeit would've been as difficult toreach in the past. caves change over time. and we think thegeology of this cave probably made it easierto access in the past. but we can tell from thesediments in this chamber that this chamber wasnever open to the surface. these hominins didn't fall in.
they were not washed in. there's no, there'snothing in there that's indicative ofwater of the strength that it would take to move bone. and we've got parts of bodiesthat are fully articulated. it's clear that the bodiesentered this chamber whole. we've got great tracesof what happened to these bones at thetime of decomposition. we've got the little traces
that beetlemandibles make on it. but in all of this, on nobone do we have something that is a mark madeby a carnivore. so, there we have it. they weren't draggedin by carnivores. they were notsubject to predation. there's no carnivore thatonly eats hominins anyway, not 15 of them. (audience laughs)they're of all ages.
this isn't people thatwere exploring a cave and got unluckilytrapped there, right? unless they were exploringwith babes in arms. they were not living there. there's no sign of detritusthat they would've, you know, of the stuff that theyate, they left in there. they were clearly notusing this chamber. they may have beenusing other chambers. we're investigating this,
but they weren't usingthis chamber to be in, except to havetheir bodies in it. we think the mostlikely scenario is that homo naledi deliberatelydeposited them there. this species with a braina third the size of ours was collecting its dead andputting them in this place. that tells us somethingreally interesting, really important i think. a lot of people comeaway with that and say,
"well, did they have religion? "was there some beliefsystem that they had?" we don't think that. i think it's not ascientific question, at this stage, obviously. we think that whatthey had was emotion. we think that they had feelingfor other social beings. we see this amongother primates. so we know that this issomething that's not a stretch.
what's differentis that homo naledi had a culture that said, "when the bodies aredead, put them here." that's a minimum. that's all thatit took, we think. but that does tell us a lot. it tells us that thesewere cultural creatures. we can't find abetter explanation at this momentfor what happened.
but we're still investigating. i can tell you that thereare other hominin remains inside the rising starcave in different places. so, we will learn moreabout what happened here. we may discover otherspecies of things, or species wealready know about. we may find more of homo naledi. just this week,from a nearby cave, sterkfontein, wasreported a new area.
this cave is oneof the most famous in the world forproducing hominin fossils, but a team was working in adifferent area of the cave and recovered atooth and a finger. and that tooth couldbe homo naledi. it looks a lot like it.we're not sure. we have to look at it in person. but one of the people workingon it is travis pickering, here in the departmentof anthropology.
so, we've really gotthe corner on the market of homo naledi at the moment. it's exciting becauseanywhere we look, we could turn thisup and discover the next piece of evidence. but what this cave tellsus more than anything else... it's less than twomiles from some of the most famous fossilsites in the world, and there it was, withthe largest assemblage
of fossil hominins ever inafrica waiting to be found. the next place we look couldhave something just as cool. it's clear that we've onlybegun to scratch the surface of what there is to discover. in a place where people thought, "well, people have beenlooking for 70 years, "what more couldthere be to find?" when you findsomething like this, and realize that the restof the continent is there,
unexplored at thatlevel of detail. our science is goingto change a lot in the next several years, andthis is just the beginning. so keep watching. this is gonna bean exciting time. we're discovering newthings all the time. we're going to havemore new things out of rising star andwithin, i'd say, a year, you're going to hearsome really crazy stuff.
so, keep watching. thank you everybodyfor coming out.
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