Well, so far the first two have been argued as prime movers: Origins of alcohol consumption traced to ape ancestor
The taste for alcohol may be an ancient craving. The ability to metabolize ethanol — the alcohol in beer, wine and spirits — might have originated in the common ancestor of chimpanzees, gorillas and humans roughly 10 million years ago, perhaps when this ancestor became more terrestrial and started eating fruits fermenting on the ground.
Chemist Steven Benner of the Foundation for Applied Molecular Evolution in Gainesville, Fla., reached that conclusion by “resurrecting” the alcohol-metabolizing enzymes of extinct primates. Benner and his colleagues estimated the enzymes’ genetic code, built the enzymes in the lab and then analyzed how they work to understand how they changed over time.
I suppose it could be argued that this could be a consequence of terrestrial (rather than arboreal) lifestyles. After all, being able to get hammered wouldn’t get tree-dwellers very far, while a ground-dweller, well, doesn’t have quite so far to fall when on a bender. It could be handy as a mechanism for being able to consume a wider array of foods. That doesn’t mean it necessarily developed as a response to ground-dwelling, but the trait could have been present beforehand but just never selected for among arboreal critters (possibly for the reasons cited above, and also because the tree-laden fruit doesn’t (?) ferment.
I like it though, and the point of the split is awfully coincidental as well.
Hey, that means alcohol ought to definitely be a part of any Paleo diet!
A paper in the November 16th issue of Science, “Evidence for Early Hafted Hunting Technology,” suggests that stone-tipped spears were used much earlier than previously thought. Reported in both Popular Archaeology and ScienceNews, the University of Toronto paper considers evidence from South Africa that suggests that stone-tipped spears were used between 500,000 and 200,000 years ago during the Middle Pleistocene by Home heidelbergensis, an ancestor to both Neanderthals and humans. This pushes back a major technological innovation to a much earlier time, and an earlier form of humans. The spears were thought to be hand-thrown, with the development of spear-throwers and other equipment to improve the speed and accuracy of spears being invented rather later.
A nearly complete mammoth skeleton has been found during rescue excavations of a Gallo-Roman excavation in France, only the third to be found in the country in 150 years. The discovery of a flint flake at the site has added to the excitement. The tool will be subject to usewear analysis and the skeleton will be analyzed for signs of butchery, to see if there is any evidence for the mammoth being a victim of human hunting. If the evidence bears out a connection between the tool and the skeleton it will be only the third in Europe where Neanderthal tools and mammoth remains have been found together. See the above page for photographs.
There’s more on this story on The Independent.
The shoulder blade of Australopithecus afarensis toddler (approx. 3 years old) from Ethiopia shows that bipedalism was not a sudden, catastrophic change in skeletal anatomy. This tiny little scapula has the same shape and orientation as shoulder blades of arboreal primates, while A. afarensis knees and pelvis show evidence of upright bipedalism. It looks like A. afarensis were doing both — sometimes walking, sometimes taking to the trees. This shows that change in locomotion was gradual, with long transitions.
“What we’re showing is that bipedalism wasn’t this sudden change that took shape in an early common ancestor,” said study co-author David Green, an anatomy professor at Midwestern University in Downers Grove, Illinois.
“As bipedalism was developing, there were other forms of locomotion that were still important.”
National Geographic has video and a story on this find (they call it “Lucy’s baby,” or Selam). Oh, and there are some really cute (afarensis) baby pictures.
(One of the less cute photos of Selam)
A recent paper on the PLOS Genetics open-access journal (Sankararaman S, Patterson N, Li H, Pääbo S, Reich D PLoS Genet 8 2012) looks at a topic that has been subjected to much debate over the years – the interbreeding of Neanderthals and modern humans. The abstract for the article, entitled The Date of Interbreeding between Neandertals and Modern Humans, which is free to access, is as follows
Comparisons of DNA sequences between Neandertals and present-day humans have shown that Neandertals share more genetic variants with non-Africans than with Africans. This could be due to interbreeding between Neandertals and modern humans when the two groups met subsequent to the emergence of modern humans outside Africa. However, it could also be due to population structure that antedates the origin of Neandertal ancestors in Africa. We measure the extent of linkage disequilibrium (LD) in the genomes of present-day Europeans and find that the last gene flow from Neandertals (or their relatives) into Europeans likely occurred 37,000–86,000 years before the present (BP), and most likely 47,000–65,000 years ago. This supports the recent interbreeding hypothesis and suggests that interbreeding may have occurred when modern humans carrying Upper Paleolithic technologies encountered Neandertals as they expanded out of Africa.
The PLOS paper has inspired the National Geographic to put together a useful summary of recent research findings about Homo sapiens neanderthalensis, challenging some of the older preconceptions, quoting various experts, including Chris Stringer, and bringing together the information from some relatively recent articles. As with the PLOS Genetics article, the emphasis in the article is on interbreeding with our fair selves, and the degree to which Neanderthals may have displayed “human” traits. If you’ve not had chance to follow the recent work on the subject and feel like sitting down with an easily digestible roundup of it, this is a good place to start.
Interesting piece on the Seattle Times that looks both at repatriation issues and highlights new isotopic research.
Kennewick Man was found in 1996 on the banks of the Columbia River in Kennewick, Washington. Columbia plateau tribes fought legal battles for nine years to have the remains of the 9500 year old skeleton reburied, but were ruled against on the grounds that the bones were so old that they could not be considered to be Native American. There’s a useful summary of the story on the Smithsonian’s National Museum of Natural History website.
Physical anthropologist Doug Owsley from the Smithsonian met last week with tribal representatives to present the results of the analysis of Kennewick Man. The biggest surprise emerged from the isotope analysis, which indicates to Owsley that he did not originally come from the Columbia Valley: “They are not what you would expect for someone from the Columbia Valley,” he said. “You would have to eat salmon 24 hours a day and you would not reach these values. “This is a man from the coast, not a man from here. I think he is a coastal man.”
The article goes on to describe some of the reactions from those attending the presentation.
UPDATE (Tony): Now that’s interesting, although I wish there were more on the analyses and less on the ‘reactions’. FYI, being “Native American” legally implies only that he was genetically related in ancestor-descendent fashion to some modern tribe, not about whether he was born here. Suggests that there was probably more movement of people going on than generally thought.
Scientists find oldest evidence of regular meat consumption by early humans
A skull fragment unearthed by anthropologists in Tanzania shows that our ancient ancestors were eating meat at least 1.5 million years ago, shedding new light into the evolution of human physiology and brain development.
“Meat eating has always been considered one of the things that made us human, with the protein contributing to the growth of our brains,” said Charles Musiba, Ph.D., associate professor of anthropology at the University of Colorado Denver, who helped make the discovery. “Our work shows that 1.5 million years ago we were not opportunistic meat eaters, we were actively hunting and eating meat.”
Original paper is here:
Meat-eating was an important factor affecting early hominin brain expansion, social organization and geographic movement. Stone tool butchery marks on ungulate fossils in several African archaeological assemblages demonstrate a significant level of carnivory by Pleistocene hominins, but the discovery at Olduvai Gorge of a child’s pathological cranial fragments indicates that some hominins probably experienced scarcity of animal foods during various stages of their life histories. The child’s parietal fragments, excavated from 1.5-million-year-old sediments, show porotic hyperostosis, a pathology associated with anemia. Nutritional deficiencies, including anemia, are most common at weaning, when children lose passive immunity received through their mothers’ milk. Our results suggest, alternatively, that (1) the developmentally disruptive potential of weaning reached far beyond sedentary Holocene food-producing societies and into the early Pleistocene, or that (2) a hominin mother’s meat-deficient diet negatively altered the nutritional content of her breast milk to the extent that her nursing child ultimately died from malnourishment. Either way, this discovery highlights that by at least 1.5 million years ago early human physiology was already adapted to a diet that included the regular consumption of meat.
I haven’t read the paper (probably won’t have time either), so I’m not sure how secure porotic hyperostosis is for meat consumption, or whether this sort of condition is associated more generally with nutritional deficiencies without regard to meat. I’m guessing a lot of people probably won’t buy it.
Archaeologist adds to understanding of evolution
The molar, according to Jacopo Moggi-Cecchi from the Universitá di Firenze in Italy, is the oldest human remains to be discovered in South Africa’s Free State Province, and is either that of a Homo erectus or perhaps the more primitive Homo habilis.
The discovery of the 1 million-year-old site is significant, Bousman said, because so little is known of early humans between 1.5 million and 200,000 years ago. Brink added that, if this tooth is confirmed as Homo habilis, then it is the youngest Homo habilis remains in Africa, showing that the evolution of hominines is more complex than is currently understood.
Seems mostly as if the significance lies in the location of the find — Southern Africa — as opposed to the find itself. Odd that it’s described as “a bone bed probably created by spotted hyenas” but there are an abundance of tools.
63,000-Year-Old Skull Supports the “Out-of-Africa” Theory, Archaeologists Say
Read more at http://www.medicaldaily.com/articles/11697/20120823/63-000-year-old-skull-supports-the-out-of-africa-theory-archaeologists-says.htm#D5wk6QZru3DeiEJK.99
Pieces of human skull found in the “Cave of the Monkeys” are being reported as the earliest skeletal evidence of ancient migration to Asia, according to archeologists.
There has been prior archaeological evidence that suggested modern humans once migrated out of Africa into Southeast Asia, but with the lack of fossils to support this theory, it has always been up for debate, until now.
The fossils supporting the migration to Southeast Asia were unearthed in 2009 in Laos in the limestone cave at the top of the Pa Hang Mountain.
Only because I don’t know much about it.
In both senses: New postcranial fossils of Australopithecus afarensis from Hadar, Ethiopia (1990–2007)
Renewed fieldwork at Hadar, Ethiopia, from 1990 to 2007, by a team based at the Institute of Human Origins, Arizona State University, resulted in the recovery of 49 new postcranial fossils attributed to Australopithecus afarensis. These fossils include elements from both the upper and lower limbs as well as the axial skeleton, and increase the sample size of previously known elements for A. afarensis. The expanded Hadar sample provides evidence of multiple new individuals that are intermediate in size between the smallest and largest individuals previously documented, and so support the hypothesis that a single dimorphic species is represented. Consideration of the functional anatomy of the new fossils supports the hypothesis that no functional or behavioral differences need to be invoked to explain the morphological variation between large and small A. afarensis individuals. Several specimens provide important new data about this species, including new vertebrae supporting the hypothesis that A. afarensis may have had a more human-like thoracic form than previously appreciated, with an invaginated thoracic vertebral column. A distal pollical phalanx confirms the presence of a human-like flexor pollicis longus muscle in A. afarensis. The new fossils include the first complete fourth metatarsal known for A. afarensis. This specimen exhibits the dorsoplantarly expanded base, axial torsion and domed head typical of humans, revealing the presence of human-like permanent longitudinal and transverse arches and extension of the metatarsophalangeal joints as in human-like heel-off during gait. The new Hadar postcranial fossils provide a more complete picture of postcranial functional anatomy, and individual and temporal variation within this sample. They provide the basis for further in-depth analyses of the behavioral and evolutionary significance of A. afarensis anatomy, and greater insight into the biology and evolution of these early hominins.
It’s the abstract and many figures from the original paper. This is a bit old as it first got to me a couple of weeks ago, but I was on vacation and not blogging (so there!).
The “pollicis longus” is a muscle of the hand. Most significant to me is that they’ve established a range of size variation in the one species so we know that the larger and smaller sized specimens weren’t from different species — always handy to know that. The other big news is that they have more evidence for true bipedalism which has been at issue in some circles. If you recall, Johanson et al. originally argued from the beginning that Lucy’s femur demonstrated that A. Afarensis was a true biped, and that therefore bipedalism came prior to a marked increase in brain size. Some had questioned just how bipedal they were. I’ve always more or less accepted Johanson’s original findings myself.