Prehistoric Autopsy; Lost Kingdoms of South America

The last episode of Prehistoric Autopsy was about Lucy – one of the most famous fossils of our ancestors (and the only individual (as opposed to species) I’d actually heard about before this series). She was a member of the species Australopithecus afarensis and lived a little over 3 million years ago. She was discovered in the early 70s, and at 40% complete was one of the most complete specimens of a hominid from that era.

This programme felt like there was a bit more padding than the other two – not quite as much to tell us about, partly because there’re fewer fossils available to figure things out from. But there was still quite a lot 🙂 From the bones that do exist (both Lucy’s and others) they can tell that this species was bipedal & walked upright – even tho they don’t have the foot bones they can see the shape of the knee joints and the pelvis. This is corroborated by data from some preserved footprints, that are presumed to be Australopithecus afarensis because that was the only primate species that’s been found in that area at that time. Experts have analysed the shape of these footprints and compared it to both human and chimpanzee footprints in similar material. The Australopithecus afarensis footprints are much more like the human ones – they have a non-opposable big toe, and the pressure patterns (like deep heel prints) are similar to human ones.

They also showed us the pelvis bones of chimps, humans & Australopithecus afarensis – you can see the difference between the chimp one & the other two really clearly. But the differences between the Homo sapiens one & Australopithecus afarensis one are much subtler. The scientist Roberts was talking to also pointed out that you can see changes in the birth canal – Australopithecus afarensis would’ve found it harder to give birth than a chimpanzee because the canal is not as wide, due to the demands bipedalism puts on the shape. But not as hard as a modern human – the brain size of Australopithecus afarensis is still pretty small, only a little bigger than that of a chimp, so the fit would not be as tight nor would it require quite as much changing of position from the baby on the way out.

Australopithecus afarensis may’ve used tools. This was a pretty controversial piece of evidence – and Roberts & McGavin didn’t agree on how plausible they thought it was. And it was nice to see how that was presented – there wasn’t a feel of some fake monolithic “the opinion of the scientists”, it was presented in a much more true to reality way. Some scientists think this, others aren’t convinced, everyone’s interested in seeing more evidence. Actually the whole series has done well on this front, they took great care to tell you about the caveats and where the evidence was slim. Lots of “we think because of reasons” and less “we know”.

Anyway, back to the tools – there’s an animal bone, found in the same context as a juvenile Australopithecus afarensis, which has two parallel grooves on it. In the grooves are fragments of hard igneous rock (as opposed to the sandstone that was encasing all the bones). This may be evidence that Australopithecus afarensis used sharp rocks to butcher meat (in some crude sense). But it may also have been due to accidental trampling of a dead animal that drove a stone against the bone. Given chimps use tools like twigs, it wouldn’t be that surprising if Australopithecus afarensis did – but really there needs to be more evidence than a single bone.

They also had a segment on how Lucy might’ve communicated – which was probably via facial expressions as well as vocalisations, because pretty much all primates do that. To illustrate this they showed us a little bit about some new research starting on Japanese Macaques, which has the eventual goal of seeing how many different facial expressions they can tell apart (and I think they have hopes of figuring out what they mean, not sure how though).

The model they built looked really good, as all of them have. They said at the end of the programme that the models were going out touring museums round the country, but when I looked it up we’d missed all the dates (because we time-shifted the programme by 3 months). A shame 🙁 Although apparently the exhibition was aimed at kids, so maybe it’d’ve been a bit shallow. There also doesn’t seem to be a tie-in book for the series, another shame – I’d’ve bought it 🙂 I did find another Alice Roberts book on Human Evolution, so if I like the book of hers we have (when I get to it) then I’ll pick that up.

Having finished up Wartime Farm last week we started on a new series – this time something that we’re only time-shifting by a couple of weeks. The series is Lost Kingdoms of South America, which is clearly inspired by the previous BBC series called Lost Kingdoms of Africa. The primary difference between the two series (as well as which continent they’re on) is the presenter – the African one was presented by Gus Casely-Hayford, who is an art historian whose family come from Ghana. The presenter for this current series is Jago Cooper, who is an archaeologist who specialises in South American cultures but not (as far as wikipedia tells me) from South America. So that gives a slightly different tone to the programmes (not better or worse, just a different perspective).

This first episode was about the Chachapoya people of Peru. Who I must confess I’d never heard of before watching it (although it became clear I should’ve at least known the name). A good start – because I’d sort of assumed we were going to get first the Aztecs, then the Incas then perhaps the Mayans, you know all the peoples we’ve all heard of before. Instead we got an intriguing people whose society really wasn’t the same as our expectations for the place & time.

The Chachapoya lived in the north of Peru, in the Andes, from about 400AD until around the time the Europeans arrived on the scene. The name we use is the Incan name for them & it translates as the Cloud People because of their high altitude villages & towns. Cooper interviewed an archaeologist in Lima who said she thought only about 5% of their sites have been properly excavated, if that. So there’s a lot still to find out.

One of the themes of the programme was that when thinking about these people we really need to take our Western preconceptions and throw them away before we can understand them. For instance the first thing we think is “but why did they live so high?” – because that’s the altitude that was best for cultivation of maize & potatoes. They lived where they could grow their food, which is a perfectly sensible thing to do. And why did they live somewhere so remote? It wasn’t remote for them – both because the people were more willing to travel further between settlements, and because the rivers and the geography of the Andes at that point combined to funnel trade from the Amazon Basin to the Pacific Coast through the lands of the Chachapoya. So not remote, but on a busy trade route. Cooper showed us some artifacts found in Chachapoya sites that included things like feathers from birds only found in the rain forest in Brazil.

Early in their culture they buried their dead up in caves on mountain cliff-faces. These were astonishing – Cooper needed the help of modern equipment and experienced mountaineers to get to these caves where the bones lay. But the floors of the caves were worn through repeated visits, so this didn’t seem to be a case of burying your dead somewhere out of the way. Later they mummified their dead – and this is why I feel I should’ve heard of them, because I knew there were Peruvian mummies, I just didn’t know which culture made them. Which is poor, really – but now I do 🙂 These mummies weren’t like the Egyptian ones which were buried & left to last out eternity in their tomb. These mummies were carried around from place to place in bags, and sometimes taken out & displayed in some fashion. A very different relationship with the dead.

Another difference in their society from what we might expect is that they don’t appear to have had a hierarchy – the Spanish had referred to this in writing from the time they arrived in South America, but there’s also evidence for it in the archaeology. The villages that’ve been investigated don’t seem to have elite housing – all the housing is the same sort of shape & size. I wasn’t entirely clear how they can tell that the one larger building most villages have is a ceremonial site & not an elite site, but they were clear that this was the case. There are also no signs of elite burials – all the dead that have been found are treated in the same. This is pretty unusual for a human society.

They also don’t seem to’ve been bloodthirsty in the way that the Aztecs & the Incas are – no human sacrifice was mentioned, nor ritual bloodletting. And in another difference from the “canonical” South American civilisation story they were conquered & dispersed by the Inca before the Spanish arrived. The Spanish actually allied with the Chachapoya to fight against the Inca. Although the Europeans did deal the final blows to the Chachapoya way of life – both through converting them to Christianity, and via the diseases they brought with them.

Prehistoric Autopsy; Wartime Farm

The second episode of Prehistoric Autopsy was all about Homo erectus, and they were building a model of Nariokotome Boy. This is a 1.5 million year old near complete Homo erectus skeleton & the most complete one ever found. They started off with context, again – Homo erectus only died out relatively recently, but was around for 2 million years, which is the longest of any human species. It’s also one of the first hominids that can be thought of as human, and we and all the other ones that were around in the recent (geologically speaking) past are descended from them. They also lived outside Africa, and were the first hominids to do so.

Homo erectus co-existed with several different hominid species over time – they talked in detail about one, Paranthropus boisei. The skull they showed had a massive jaw, a skull ridge and very flared cheekbones to fit the chewing muscles behind. A diet of particularly solid things seems plausible, like nuts and seeds. As well as that sort of food there’s evidence of wear from grasses on their teeth.

They showed us research into the climate over the time period – I loved this bit, there’s just something so neat about being able to find out what the world was like so long ago with such a simple concept. They do it using samples taken of the sediment on the ocean floor. It’s laid down layer upon layer over time, and you can look at things like the sort of mud it is and the sorts of plant seeds/pollen you find in it to build up an idea of what the weather and landscape was like on nearby continents. We got shown a particular example of a core where you could see a colour change in the mud from top (~5000 years ago) to bottom (~10,000 years ago), and told us that the changes correspond to a change in the nearby climate (East Africa, if I remember right) from wetter to more dry. Over the 2 million years that Homo erectus existed the climate seems to’ve undergone lots of swings between hotter & colder or wetter & dryer conditions and they speculate that why Homo erectus survived and the other hominids didn’t is that Homo erectus was more adaptable.

And that they were more adaptable because of their bigger brains and because of the different way they interacted with the environment around them. There’s evidence that Homo erectus used fire, and they cooked their food (at least at the end of the time period, I wasn’t clear if there was no evidence from earlier on or if they hadn’t done the analysis (yet)). Their tools are more sophisticated than earlier hominid tools – instead of just breaking rocks for a sharp edge their tools are carefully shaped and show evidence of being planned and involving skill to make. So Homo erectus seems to’ve had the cognitive ability to shape the environment to suit themselves, rather than put up with the environment they find themselves in. There’s also evidence that they took care of older members of their groups – a skull has been found where the individual lost their teeth a few years before death, and quite clearly wouldn’t’ve survived without help.

Because of the model building the programme also spent some time discussing the probable physique of Nariokotome Boy. Homo erectus show many adaptions for running, and were probably lean and hairless (to the extent that modern humans are hairless, I mean). Because of the lack of hair they’d’ve had dark skins to protect themselves from the UV of the African sun – and this limited their spread north, they don’t seem to’ve got the low melanin mutation that permitted us to live in more northern climates. Also in this section they showed us evidence that Homo erectus may’ve suffered from tuberculosis, which is astonishing – it is a disease that we get from cattle originally, and was assumed to’ve become a human disease only more recently when modern humans started living in close proximity to cattle because they’d become herders. The marks and signs on the Homo erectus skull they were looking at (not Nariokotome Boy, another one) were very similar to the ones on a modern human who’d died of TB, so seemed convincing evidence. Which raises all sorts of interesting questions.

We also watched the last episode of Wartime Farm, which unsurprisingly covered 1945 and the immediate aftermath of the war, as well as wrapping up with a “what we’ve learnt” segment. So they were mostly concentrating on the fact that once the war was won, that didn’t mean life returned to how it had been pre-war – not only did people still need fed, but in some ways the situation was even more precarious because Britain was close to bankrupt and couldn’t afford to import food yet the fields were becoming less fertile due to a lack of manure and from being over-farmed. They also talked about the celebrations that people had (and the thing they dramatised was a firework elephant, which was awesome 😀 ). And they harvested the wheat crop they’d spent the year growing, using a brand new combine harvester (well, 70 year old one …).

This was a good series, although I’ve struggled to write more than a paragraph per episode. I’m not quite sure why, but I guess partly because there was a lot of “look at how we did things” which isn’t easy to transform into text. I did feel that they spread it all too thin, perhaps they couldn’t do it half the number of episodes, but I do think they could’ve cut it down a bit. The format of half-dramatising, half-telling still feels like it shouldn’t’ve worked, but they pulled it off very well.

Prehistoric Autopsy; Wartime Farm

Last night we watched the first part of Prehistoric Autopsy which was all about the Neanderthals. This is a three part series presented by Alice Roberts & George McGavin plus a whole team of experts – the format is that they have a “lab” set up with various different experts & they demonstrate some of the research that’s been or is being done about three different human/ancestral species and use this knowledge to build a life-size replica of the species in question. It suffers a little from “staged conversations” syndrome & an almost complete lack of on-screen chemistry between the two primary presenters but other than those two niggles it was a fascinating programme.

So they started by giving us context for Neanderthals – not that long ago by palaeontological standards we weren’t the only human species on the planet. If you go back to ~70,000 years ago there were 4 species as well as Homo sapiens: Homo floresiensis (who died out about 12,000 years ago, which is about the same time as the Chinese were starting to make pottery), Denisova hominin (who I’d never heard of before, wikipedia tells me this is a branch from Neanderthals), Homo neanderthalensis (Neanderthals, died out around 30,000 years ago), Homo erectus (died out around 70,000 years ago). Neanderthals moved out of Africa & lived in Europe, then Homo sapiens evolved in Africa and independently moved into Europe later on.

They then talked us through lots of different evidence for what the Neanderthals looked like & how they lived, whilst at the same time showing us the building of the replica (based on an actual individual skeleton). Lots of fascinating things, quite a lot of stuff I didn’t know before, so I shan’t try & list everything that made me think “ooh, neat” 🙂 I knew that there’d been work that showed we (northern Europeans) are more related to Neanderthals than you might think, but I hadn’t realised that they’d actually sequenced the whole Neanderthal genome. And the data they showed for relatedness was quite impressive – looking at 500 people of West African descent & you see under 2% relatedness to Neanderthals (with a nice normal distribution) and then looking at 500 people of Northern European descent and you see 2-4% relatedness to Neanderthals (again, nice normal distribution that doesn’t overlap the West African one). Looks pretty clear there was interbreeding going on in Europe 30,000 years ago.

Neanderthals also had more culture than one might’ve thought – there’s a painted shell with a hole that looks like where you’d put one if you were making a pendant, that was found in association with Neanderthal remains. There’s also a cave-painting that has had some of the paint dated to ~15,000 years before the first signs of Homo sapiens. They spent some time considering if Neanderthals could talk, too – but that was a little less convincing. They also looked at how Neanderthals hunted, and how they made clothes. You can tell from tools found that they must’ve scraped hides to make them pliable for making clothes, and you can also tell this from the arm bones of the skeleton. You could also tell from the wear on the teeth that they worked the hides with their teeth too.

Oh, and thinking of teeth – one of the really neat bits was that there’s a group that have examined Neanderthal teeth from a skeleton of a young girl, using a synchrotron. The images generated allow them to see and count the growth lines in the teeth – at a resolution of 1 per day. That means they could count up how long the girl had lived since her teeth came in, and instead of the 6 years estimated from the state of the bones it turns out she’d lived for about 3 years. So Neanderthals matured at a much quicker rate than us, and they speculated in the programme that this might be part of why we still exist and are thriving & the Neanderthals aren’t. That we have more time to learn while we grow up, and this makes us more adaptable & gives us an edge in competition.

I could ramble on for longer, but I shall stop there. I’m looking forward to the other two programmes when we get to them & I’d definitely recommend watching this one if you have the chance (and are interested in that sort of thing).

The other programme of the evening was the seventh episode of Wartime Farm – covering 1944. We had carrier pigeon training (because they were extensively used during the war in particular to relay messages during the D-Day landing), POWs being used as farm labour (the expert on this segment was a German chap whose Grandad had been one of those POWs which was a neat touch), the troops gathering pre-D-Day, basket making, flax harvesting. Oh and some terrible German bread – bread was never rationed here, but it was in Germany. And in desperation there were recipes for wartime black bread that were appalling – the one they demonstrated was silage, grass clippings, sawdust, fermented rye (better hope for no ergot!) and honey. It looked a bit like black bread once it had been cooked, and they ate it and said it didn’t taste too bad – but pretty much it was the sort of thing you’d eat if you were reduced to eating grass, this was at least a palatable way to do it.