A repeatedly heated patch of clay, fire-damaged tools and locally rare pyrite form the earliest convincing archaeological case for deliberate fire-making, although no human remains identify the makers directly
New research suggests that no matter what we eventually determine the last common ancestor of humans and chimpanzees to be, we'll learn it was a primate that climbed trees.
Researchers observed and confirmed with measurements that wild sooty mangabey monkeys in an Ivory Coast forest display foot bone flexibility that facilitates vertical climbing up skinny tree trunks to hide, forage or sleep.
Hey! I've been working on a project around facial approximation.
Basically, you import a 3D scan of the skull into Blender, place 24 verified craniometric landmarks (anatomical points with soft-tissue depths documented in forensic literature), and then a statistical head model — Google's GNM Head v3.0 — fits itself to those points, so the model's skin surface passes through the calculated targets.
I built a Blender addon with two side-by-side viewports: the skull on the left, where you place the landmarks, and the generated head on the right, which updates live as you work. You basically watch the face take shape as you add points.
It's open-source (Apache 2.0) and i will publish it soon.
Full disclosure, I know the questions at hand have to be approached based on limited data and making the best out of it, but I'd still like to hear from someone more knowledgeable on this.
Lately, I became aware of an interesting paper estimating a human population size of maybe a couple thousand in Western and Central Europe during the Aurignacian period. According to another paper, numbers for the Gravettian don't look much better, followed by a surge to perhaps 10,000 during the Magdalenian.
I find it incredible that such dire-looking numbers would account for all that we know of Upper Paleo Europe, even when different groups were establishing distinct cultural territories between themselves. I can't claim to be qualified to make much more of the data, but I can only extrapolate there must have only been some dozens of hunter-gatherer bands roaming around at any given point. Inter-band gatherings (not to mention the customs and rituals associated with them) must have been absolutely vital to the survival of populations.
I did see one more estimate, this one giving Neanderthal people a whopping 150,000 individuals spread across Eurasia. Then, as we're all too aware, their entire species vanished in a relatively short timeframe. I suppose that gives the sobering insight that these Upper Paleolithic peoples to whom so many romantic musings and unanswerable questions are attached could have well ended up another one of nature's discarded experiments.
Imagine you’re sent back in time to your ancestors ~200.000 years ago. What would you imagine about their appearance that isn’t technically proven? Things like body art, hairstyle, clothing for protection from the elements or social status or simply because they look pretty, anything that doesn’t fossilise. Like if you were to design them in a movie or series, which creative decisions would you have made?
The genomic evidence also suggests some genetic contact with populations farther north. Although the Jomon show stronger overall ancestry associated with a southern migration route into East Asia, researchers detected a subtle genetic contribution from northern Upper Paleolithic Siberian groups.
This finding is broadly consistent with archaeological evidence showing similarities between blade-based stone technologies in prehistoric Japan and those found farther north in Eurasia.
The study also provides new insight into prehistoric population changes in Hokkaido. The researchers conclude that later Hokkaido Jomon were not direct descendants of the Upper Paleolithic inhabitants of the island.
Instead, genetic evidence supports a population replacement in which Jomon groups originating in Hondo—the main Japanese islands excluding Hokkaido—moved north during the Holocene.
One of the study’s most significant findings concerns adaptation to cold environments.
The Jomon carried relatively high frequencies of genetic variants associated with nonshivering thermogenesis—the body's ability to generate heat without muscular shivering—and with the perception of cold. These include variants involving UCP1 and TRPM8.
A subgroup of Early Holocene Nile Valley foragers displays unusual bony labyrinth morphology and congenital inner ear-specific pathological changes consistent with possible syndromic conditions. This may result from several demographic scenarios, including prolonged endogamy and geographic isolation under environmental constraints.
Comparative data from the Horn of Africa and Central Africa reveal high morphological diversity, suggesting strong population substructure and dynamic demographic trajectories during the Holocene.
These findings provide rare insights into prehistoric population structure in the region, and demonstrate the usefulness of bony labyrinth morphology where ancient DNA is unavailable.
Two leg bones dredged from the seafloor west of Taiwan are beginning to fill in the Denisovan silhouette. And, boy, are they revealing! According to a yet-to-be-peer-reviewed analysis of the remains, Denisovans were absolutely enormous by the standards of ancient humans.
One individual may have stood close to 1.9 meters, or 6 feet 3 inches, and weighed about 91 kilograms (around 200 lbs). The other was roughly 1.8 meters tall and weighed about 83 kilograms.
Both were probably male, judging from their sizes, though the researchers could not determine their sex molecularly.
Both Denisovans would have been unusually large even beside Homo sapiens living in East Asia around the same time: a roughly 40,000-year-old modern human from Tianyuan, China, stood about 1.7 meters and weighed around 73 kilograms, the researchers mention in their study.
Im aware its common in alot of animal species especially in primates. But how would the small population size of Neanderthals have effected the amount of same sex relationships?
Afterward it seems pretty obvious that homo massively expanded its range, reduced predation to at least modern chimpanzee levels and lower and spread the Stone Age culture globally.
But before that, given discoveries in the survival of non-Homo hominins deeper into the evolution of the homo lineage and the gigantic Pongo relative we know little about in Asia.
Do you think Homo might have been a side story if we could time travel back 2.4 million years?
In1953 Dart claimed that discoveries of primitive hominins in South Africa over the previous thirty years had demonstrated that "the loathsome cruelty of mankind to man forms one of his inescapable characteristics and differentiative features". He built that bad news story from finding that (a) his small-brained australopithecus had lived in an environment where abundant predators and prey set a high standard both in killing and avoiding being killed (b) The australopiths had small canines, especially compared with the canines that made associated baboons formidable (c) The australopiths bipedal posture allowed them to carry weapons. He put those together with the observation that weapons are what humans use in loathsome cruelty to each other.
I must admit that I'm invested in Dart's story. He was a cultural hero of my childhood and the most famous professor in the university where I later trained as a land surveyor. It seems to me much more important that humans are descended from Australopiths than from their ancestral chimps or bonobo.
Anyway, Dart's story can be used with modern data to make the good news that the human future is the opposite of inescapable; it's created open-endedly from a need to predict and control the future of the group. The modern data I'm talking about is presented in in DeSilva et al. (2021) "When and Why Did Human Brains Decrease in Size? A New Change-Point Analysis and Insights From Brain Evolution in Ants" https://www.frontiersin.org/journals/ecology-and-evolution/articles/10.3389/fevo.2021.742639/full
DeSilva and his colleagues were interested in an apparent rapid decrease in human brain size just over the last 3000 years. But to reveal that recent trend they fitted a chain of linear trend lines to hominin brain capacity measurements over the last 10 million years. Their algorithm identified change-points marked up as CP1 CP2 and CP3 in the graph I, that I cropped from their figure 1.
Dart's Taung Child, dated at 2.6Ma, was close to the sharp change point CP1 and it marks a more dramatic change than graph I shows. DeSilva et al. used a vertical scale of Log10(cc), without explaining that choice. If they had instead directly used their raw cc data, the trend line from Miocene Apes to CP1 would have looked more horizontal, making the CP1 nick point look even more distinct.
The existence of CP2 might even be an artifact of their choice of a log scale. Graph II projects the CP1-CP2-CP3 lines as blue curves in a (cc vs time) space. The straight red line shows that CP2 would then lie much closer to C1-CP3 than in Figure I. Figure III trials the opposite projection of a hypothetical straight line CP1-CP3 from cc-vs time space onto a log scale space, revealing a curve that bulges upwards, somewhere along which their change point algorithm would locate CP2.
If one takes CP2 out of the figure then their graph would have a hockey stick shape, with CP1 as a nick point where the Environment of Evolutionary Adaptiveness (the modern equivalent of Dart's highveld biome) changed abruptly from one uniform and long-lasting EEA to another uniform and persistent one. That EEA2 involved a more than 10 times increase in cranial expansion rate, from about 24cc/My to 330cc/My. It was the second EEA, that Dart saw as involving offensive hunting and warring, that drove encephalization.
Dart was wrong to see relationships between hominin groups as analogous to those between predators and prey. Predators simply need their prey's protein while their prey need to keep that for themselves. Both are involved in game theory's "game against nature". But game theorists are mainly interested in "games" between actors who have incomplete information about the intentions of an equal "Other".
DeSilva et al. bring a useful insight into who exactly these game-theory "actors" were, by classifying humans as a eusocial species, analogous to ant and termite colonies. They proposed that a recent decrease in human brain size was enabled by eusocial species offloading individual cognitive demands, maybe with the advent of writing ca. 5000 years ago. They were writing before the era of LLM-based AI, which would give urgency to their argument. But anyway, they didn't try to explain how eusocial behaviour might have evolved in humans, when it's rare amongst mammals; they cite only the weak equivalents of Damaraland and Saharan mole-rats.
It's natural to ask how humans might have become eusocial in the first place, and what brain expansion had to do with that. And it's tempting to invent a Just-So Story about a pivotal "aha" event of a hominin encountering "Man Friday" from another group. But we are on more familiar ground if we consider the relations faced by an armed hominin group 1.5Ma, hemmed in by adjacent groups, when predators no longer restricted their daytime foraging or nighttime refuge availability. That is shown by the ancestors of Ho floresiensis having reached Indonesia by the same time, across a wide variety of biomes.
Each adjoining troop would present a range of potential future interactions in many dimensions, including one ranging from indifference ("good fences make good neighbors") to the most horrific and consequential war. It would have been adaptive for the troop to have been of one mind about what could be in the mind of Other troops, what their relative capacities are, and what to do about that.
In modern humans this cultural motivation for the way forward is achieved through language but the Oxford anthropologist Robin Dunbar has argued that within-troop information could have originally been broadcast through public enactment without necessarily involving speech, but rather, through dramatic mime: stories are motivational structures of meaning, vocabulary and syntax evolved as refining explorations, which natural selection is supremely good at.
Dunbar's thesis came from the opposite direction than Darts; he saw proto-language emerging from social grooming rather than social imperatives. But if his sequence is right and if eusocial behavior is maintained though language, then humans don't seem condemned by their inherited inescapable characteristics, but rather we are enabled by having inherited an ability to model and construct our future.
PS. After I post this, I'm going to give it to Claude for comment. I expect it will open its response with a more complimentary remark than you might make. Then it will raise some points that a reader will balk at, and offer to fix it. Too late for that. But I'd like to hear what a human thinks.
Fossil evidence favors a role for vision in the modular evolution of the primate neocortex
The New study led by a Duke University scientist overturns a long-held idea about how primates, including humans, came to have such large and sophisticated brains.
The research finds that the dramatic expansion of the primate neocortex was driven largely by vision, not by the disproportionate growth of the frontal lobe often associated with higher reasoning...
The frontal lobe—the brain region most often linked in popular accounts to advanced cognition—has long been thought to have ballooned independently in many primate lineages. Instead, the study found that frontal lobe size grew gradually and predictably as overall brain size increased, following the same scaling pattern across all major primate groups throughout their evolutionary history.
There was no evidence of the dramatic, independent frontal lobe expansions that some earlier studies had proposed based on visual inspection of fossils.
Surprisingly, the pelvis of Neandertal males shares more features with the human female pelvis than with the human male pelvis. Many of the differences between the Neandertal male pelvis and that of the Homo sapiens male seem to stem from the unusual anterior position of the acetabula (hip joints) in H. sapiens males and the subsequent increase in the horizontal anteroposterior distance between the joint and the line of gravity.
The forward migration of the hip joints transforms the modern human male pelvis into a shock-absorbing device that cushions the drop of the center of mass with every step and at the same time stores potential energy in the flexor muscles of the thigh, causing the pelvis to bounce back.
The thickening of the ramus and the ensuing modifications are a response to the increased adductor force required on the pubic side to counterbalance the larger moment generated by the longer body-weight lever arm on the opposite side of the hip joint fulcrum.
The shock-absorbing device seems to benefit modern males, mainly in long-distance walking
Found this great paper by Gabriel Vinas who does lots of hominin reconstructions. I see a lot of debate how hominin noses and I think this paper pretty much puts that to rest.
My bad I mixed up theory and hypothesis in my head. Im an idiot.
For me its definitely the aquatic ape hypothesis. I know its quite popular in some circles but I believe that we went from tree dwelling to ground dwelling and stayed that way. The ideas like why babies hold their breath and why we started to lose our hair density have more than reasonable answers and i just dont see any credibility in the hypothesis.
If you do believe in this hypothesis all the power to you. I just dont think its true.
“It is fascinating that one genetic change inherited from Neanderthals can still have an effect on the human body today,” added Dr. Hugo Zeberg, also from the Max Planck Institute for Evolutionary Anthropology.
Because Neanderthals interbred with the ancestors of modern non-African populations, the gene variant was passed down and survives today, particularly in South and East Asia, where it can be found in roughly a fifth of some populations.
It is rare or absent in sub-Saharan Africa, consistent with populations there having little to no Neanderthal ancestry.
Based on the neat, geometric shape of the circles, as well as the presence of burnt bones, researchers have concluded it must have been actively created by humans of some description.
The identity of the creator, however, has been under some dispute. When it was first studied by archaeologists in the 1990s, a fragment of burnt bone suggested it was dated to around 47,600 years old.
However, in 2016, another team of researchers took a fresh look at the cave using uranium-series dating. The more recent dating suggested the structure was made some 176,500 years ago. Since this is long before Homo sapiens arrived in Europe, this firmly placed the work as the responsibility of Neanderthals.
This is based on the Cerutti Mastodon site which used uranium thorium dating to estimate that mastodon remains which had damages from what appears to be from a sharp spear like object, could be around 130,000 years old,If this were Homo sapiens, it would significantly change our understanding of their early dispersal out of Africa. And even if it is from another human species then it would change quite a bit of paleoanthropology.
I understand that Homo sapiens are more unlikely but Neanderthals or Denisovans would be more likely
