Thanks to Carl at A Hot Cup of Joe for passing this along – if you navigate to the CV page of Milford H. Wolpoff, you’ll find a number of freely accessible (PDF) papers, many or indeed all of which should be of interest to readers here.  They span a time frame of more than three decades, 1968-2004, and I’ll attempt to address at least some of them in due course – topics cover pretty much the entire gamut of human evolution, and include some discussion on multi-regionalism as opposed to multiple origins.

The Journal of Experimental Biology has published an interesting paper about some unique features in sprinters: longer toes and shorter ankle joints. The only one flaw is that their sample size is limited, they only compared 12 collegiate sprinters with 12 non-athletes of the same height. Regardless, from a physical anthropological point of view, this comparative & biophysical analysis informs us what traits help humans sprint faster.

The significance of long toes and short ankle joints can be explained from a purely physics perspective. From the start of a sprint, the only way a human can accelerate is through the transfer of energy from the force of the leg muscle to pushing on the ground. The advantage of longer toes provide maximum contact with the ground just a little bit longer than shorter toes.

The ankle joint is shorter because there is an inverse relationship between tension force and distance — think torque and angular momentum. Sprinters have a 25% shorter distance between the Achilles tendon and center of rotation of the ankle. The Achilles tendon is the common attachment of the gastrocnemius and soleus muscles into the calcaneus. When contracted, these two muscles flex the knee and plantar flex the foot. With a shorter ankle joint, these muscles shorten less for the same joint rotation. If muscles shorten less, then they shorten more slowly. This facilitates them to produce greater force that more than compensates for the reduced leverage.

When these two adaptations are combined, the authors figured that the greatest acceleration is achieved when the Achilles tendon lever arm is the shortest and the toes are longest. Comparing these anatomical features to other sprinting animals, like ostriches, greyhounds and cheetahs, they authors observed that they also have feet built for sprinting with similar features.

The authors, who are not physical anthropologists, state in press releases that they think these adaptations could have had some evolutionary backing. They raised the tired hypothetical scenario where early human ancestors, now those with longer toes and shorter ankle joints, were better able to run away from the saber tooth tiger or marauding tribe and reproduce that trait. But I disagree, while there certainly is an inherited component to the size and shape of our bones, muscles, and joints, our bodies are malleable and depending on training, our bones and muscles can change!

Furthermore, the majority of humans are not sprinters, as I understand it. In fact, most of us are good at long distance motility. Our bodies are extremely inefficient at sprinting but we’re really good at staying the course! Most of us have lots of Type I muscle fibers, slow but fatigue resistant fibers. Anyways, I don’t mean to rag them on this concept, as I mentioned they aren’t physical anthropologists and they seem to only be speculating on this last point. Either way, I believe the observation they made is interesting!

Knight, K. (2009). SHORT HEELS GIVE ELITE SPRINTERS THE EDGE Journal of Experimental Biology, 212 (22) DOI: 10.1242/jeb.039735

Lee, S., & Piazza, S. (2009). Built for speed: musculoskeletal structure and sprinting ability Journal of Experimental Biology, 212 (22), 3700-3707 DOI: 10.1242/jeb.031096

Ciarán Brewster, a.k.a. adhominin, just tweeted about three book reviews. The reviews, written by Robin McKie of The Observer, cover recent books on cooking and human evolution which were written by some pretty big names in anthropology:

• Catching Fire: How Cooking Made Us Human by Richard Wrangham
  Wrangham’s thesis is that the advent of cooking reduced our energy demands of actually chewing, we do have a smaller muscles of mastication, jaws and teeth. This shift diverted the energy we would be spending on the act of eating, along with eating more easily digestable nutrients, to developing massive brains. Something I didn’t know and learned in the reviews is that people who eat only on uncooked meat or veggies will slowly starve, sucks for those on the raw food diet.
• The Well-Dressed Ape: A Natural History of Myself by Hannah Holmes
  Holmes addresses the fact that human females are the only primates with enlarged breasts and discusses theories on why. She says that the large breasts allow more feeding time for infants, which kept the babies more compliant and less likely to cry, which would otherwise attract predators. Our relatively hairless skin also evolved as a direct function of predator pressure, early human ancestors needed greater surface area to cool off our skin with sweat as they ran from predators in the savannah.
• The Humans Who Went Extinct: Why Neanderthals died out and we survived by Clive Finlayson
  Finlayson discusses why and possibly how Neandertals were so easily replaced by modern humans. He argues that the harsh landscape of early Africa, about 100,000 years ago, when modern humans emerged forced them to learn new technologies and lifestyles that were, “more inventive and intelligent as they struggled for survival. European Neanderthals, untutored in the school of hard knocks, were no match for our ancestors when they met.”

These books seem to be entertaining, you should check them out if you haven’t already. Also, if you’re on Twitter and looking to follow some active anthropology minded folks, I’ve compiled what I believe to be a pretty comprehensive list of anthropology Twitterers. Check that out too, and follow it… If I’m missing anyone please let me know on Twitter or via this post’s comment thread.

Back in August of this year, two words I frequently encountered when trying to visit sites of interest in Andalucía, southern Spain, were“Cerrado” (closed) and “No”, which as a tourist you take in your stride, leg it to the nearest hostelry and reconsider the rest of the day from the perspective of its slightly less interesting alternatives. As an eminent archaeologist working on what is potentially one of the more important sites in Spanish archaeology, with the prospect of confirming the latest known Neanderthals to have lived anywhere in the world, you might hope for more positive words from those tasked with permitting your work to go ahead unhindered. But as we see from the sorry tale unfolding below, this is not always the case, especially where the cave of La Carihuela is concerned.

Martin Cagliani at Mundo Neandertal points us towards this story, in which Spanish archaeologists are complaining that the local Junta (legislative assembly) of Andalucía will not allow the re-excavation of the Mousterian layers in the cave which it closed in 1996, (although work seems to have been conducted at least as late as 1998 by Carrión, linked PDF, Fig.2) where it is claimed there are Neanderthal remains dating to around 21,500 years bp, located within the cave of La Carihuela, about 45 km from Granada. If confirmed, this would make these Neanderthals far younger even than those whose artefactual traces have been found at Gorham’s Cave on Gibraltar dating to around 24,500 bp, at the same time perhaps taking the species’ existence right up to the Last Glacial Maximum.

The news article referred to is in Spanish, and is reported at Público.es, from which I’ll roughly translate some of the more pertinent points, while there’s also a freely accessible paper (PDF) on the subject of pollen sequences in the cave, as well as a description of its layout, the stratigraphic sequences within the galleries,  published in 2006, to which I’ll briefly refer throughout.

The report begins by describing how the cave might be the site of the very last Neanderthals tthat once walked this planet, because following the discovery of a male (Neanderthal) skull back in the 1950s, in the vicinity of Mousterian stone tools, it was realised shortly thereafter that according to pollen analyses, the layer from which the fossil had been retrieved might date to as late as 21,500 years bp.

Excavations began in earnest during the late 1970s, and by the early 1990s, a team of 30 researchers were working there, putting it on a par with Atapuerca, near Burgos in the north,  for the amount of effort invested in the site. But in 1996, following what is described as an arbitrary decision by local authorities, this work came to a sudden halt, and despite repeated requests from the archaeological community to reopen the cave, the Junta has remained obstinately silent on the case, allegedly not even picking up the phone to engage in the debate, according to D. Gerardo Vega Toscano. Profesor Titular, Dpto. de Prehistoria. UCM, Madrid.

He remarks that the scientists in this case are effectively at the mercy of the politicians, who basically don’t give two hoots whether the cave is the last refuge of the Neanderthals, or simply a hole in the ground.

One wonders from reading this whether the Junta is a fit and appropriate body to hold sway over such affairs, and moreover where the Spanish Ministry of Culture stands in this – surely it should be they who decide the scientific importance and appropriate funding levels required by such sites, and I find it hard to believe that no-one from the Ministry has seen fit to intervene.

Vega Toscano is for his part unconvinced of the very late date of 21,500 bp proposed for the remains, which he cites as absurd, opining instead that a date of 28,000 years bp is a more realistic proposition – it should be noted here that the estimate based on the pollen samples uses 28,440 bp and 21,430 bp as its parameters, with the real date presumably falling somewhere in between the two. The oldest known actual remains of Neanderthals are from Zafarraya, occupied between 31,000-27,000 bp, and the remains at La Carihuela should provide secure dates assuming that the specimens are in good enough condition.

Gorham’s Cave on Gibraltar is also known as a late Neanderthal refuge, with a most recent date of 24,500 bp ascribed there to Mousterian artefacts, while in Portugal at Lagar Velho, what appear to be the remains of a hybrid Neanderthal child are also put at 24,500 bp, so there seems no reason why a similar date shouldn’t apply at La Carihuela, and maybe 21,500 years bp, or a millennium or two beforehand, in the overall context isn’t completely out of the question. The fact that Mousterian technologies appear to have continued to be employed right up to the very end is interesting in itself, suggesting a lack of contact between archaic and anatomically modern populations – whether further investigations within Carihuela will reveal late-surviving Neanderthals were using bone or antler implements in addition to their own Mousterian tool-kits remains to be seen, but seems doubtful.

Contrary to the opinions of Vega Toscano, there is however support for the much later Neanderthal survival dates, as the article goes on to report the opinions of José Carrión, Professor of Botany at the University of Murcia, who remarks that 21,000 years bp marks the start of the Glacial Maximum, when temperatures plunged ever deeper for the following 3,000 years, a situation he believes could have tipped Neanderthals over the edge, coinciding with the extinction of fauna such as the mastodon and sabre-toothed tiger. (Although Neanderthals had previously survived through at least 2 previous ice ages, they had done so in the absence of competition from AMH, and as far as I’m aware, no major faunal extinctions had taken place in the earlier glaciations either, or at least not to the extent that Neanderthal prey animals disappeared from the menu).

Carrión further makes the point that apart from pollen dating, the bones from La Carihuela can be dated, and so might yet reveal themselves to be younger than the Gorham’s Cave presence – whether the fossil skull mentioned earlier has been dated isn’t stated here, and whether it continues to languish unexamined in a Granada museum, isn’t clear. Other researchers have dismissed the idea that climate alone could have accounted for the demise of the Neanderthals, preferring instead to cite a multitude of inter-related factors.

The story goes on to explain that although there is funding available to continue work inside the cave, the Junta refuses to grant permission, but again, there is no reason specified for their lack of co-operation, indicating that whoever is advising them is either badly out of touch or have unspecified reasons of their own for this unreasonable denial of archaeological research. Rodríguez-Vidal blames what he calls parochialism on the part of the Junta, and for some reason making an oblique reference to them acting like Sicilians, viz:

“Pero nos topamos con la mentalidad provinciana de la Junta, que es similar a la siciliana”

Having read that I’m half tempted to stretch a point and wonder if the Andalucían authorities or the Ministry of Culture aren’t holding out for some sort of media deal, whereby they hope to cash in on filming and reporting rights to La Carihuela, via whoever might make them the proverbial offer they can’t refuse. The confirmation of late-surviving Neanderthals would be attract much media attention, putting Andalucía firmly on the map of Iberia’s most important prehistoric sites, although I find it hard to believe that cultural organisations would act with such a degree of cynicism for over a decade, or that there would be significant payola to make it a worthwhile course of action. But unless there is some other obscure reason such as an imminent danger of collapse, it isn’t hard to sympathise with the frustrations of those archaeologists who would prefer to get on with the job in hand and conclude their research.

It is further stated that these problems with local authorities don’t exist in Catalonia to the north, although whether there is any communication between regional Juntas in such matters isn’t stated – once again, the silence from the Ministry of Culture seems deafening by its absence, as logic would imply that such decisions are ultimately their responsibility. However, I know from personal experience that the Spanish Ministry of Culture can on occasion act in ways which seem incomprehensible to the uninitiated. During the summer I tried in vain to visit a painted cave, Tajo de las Figuras, near Benalup,  also in Andalucía, only to be told by a slightly grumpy security official that the site was now closed to the public, and had been since last October. My wildly exaggerated and improbable claims of being an archaeologist who had travelled all the way from London in order to see some of the most southerly cave paintings in Europe, were met with an impassive shrug of the shoulders, with the suggestion that if I wanted to know why it had been closed since late 2008, I might be better off addressing my concerns to the Ministry of Culture, as the man at the gate denied all knowledge of why the place was shut in the first place. As far as I can tell the cave is shut for restoration – according to this link, there used to be a custom of wetting the cave walls with water in order that tourists would be able to see the paintings more clearly, with the result that a layer of damaging grease has built up over the very same images.

There are faint signs that rocks at La Carihuela were also decorated in the Palaeolithic, but as far as I know there are no paintings on the cave walls, or at least any that date to before the LGM.

Back to the story once more, where the problem of the proposed early dates is raised once more; there is tantalising evidence from Cantabria in northern Iberia, where in the Picos de Europa, in the cave of Esquilleu, where Javier Baena a professor of prehistory at the Autonomous University of Madrid, details finds of Mousterian artefacts dated to “slightly more than twenty thousand years”, which again seems like an intriguing indication of late Neanderthals, once again living on the periphery of the Peninsular, albeit at slightly higher latitudes than those mentioned above. If confirmed, it would confound the ‘north-to-south’ extinction model of the Neanderthals that has been implied by findings of late Neanderthals clustered exclusively in the south.

I mentioned at the top that there is a paper detailing the cave itself, so here, courtesy of Santiago Fernández et al, from their paper published in Geobios (PDF) in 2007, and from which this is the abstract:

A new pollen sequence (ca. 15,700–1250 yr BP) is presented for three stratigraphical sections of Carihuela Cave (Granada, southeastern Spain), thus completing a record that covers from the last Interglacial to late Holocene. The Late Glacial is characterized by open landscapes with junipers and early colonisation of Quercus, while the Holocene is depicted by mixed oak forests, with a diversity of broad-leaf trees and scrub, which decrease after ca. 5470 yr BP synchronously with the expansion of xerophytes and occurrence of indicators of anthropogenic disturbance.

The whole pollen record of Carihuela fits into the general trends described for reference pollen sites of southern Europe, including Padul in the province of Granada, and other sequences from Mediterranean Spain, through which the heterogeneity of environmental change increases from mid to late Holocene. We conclude that, in contrast with other regions of Spain, deciduous Quercus-dominated forests are very old in eastern Andalusia, thus conflicting with floristic phytosociological models of vegetation change that imply that monospecific Q. ilex/ rotundifolia woodlands are the potential mature forest in the region. Dating results suggest that the last Neanderthals of Carihuela lived between ca. 28,440 and 21,430 yr BP, which agrees with the postulation that southern Spain was the latest refugium for this human species in Europe.

There follows a description of the cave itself, facing north and located near the Río Píñar which flows in the valley below, tells us there are three entrances, all of which converge on a central gallery, from which another passage at the back heads into the hillside. Here’s a description from the archaeological perspective:

The relative importance of eolian, fluvial, and biotic transport as sediment sources at Carihuela has apparently varied through time (Carrio´n et al., 1999). Because of the north facing and overhanging situation of the cave opening, eolian transport may have been present all the time introducing windblown silt and clay but nowhere inside the cave uniform sedimentary structures are found that characterize eolian transport (Davis, 1990). Considering the particle features, water transport could have been important in Units XII, XI, VIII, VI, and II–I (Carrio´n, 1992). Biotic transport is evident in Units VII and VI (Vega-Toscano, 1988; Carrio´n et al., 1998). On the other hand, cave spall depending on internal weathering of walls and roofs have been a source of sediment in Units X, VII, V, and III, which coincided with stadial stages in the pollen sequence.

Lithic implements of Units XII–V are typical of the Mousterian. In its uppermost part, Unit IV displays a Mousterian-like industry without leptolithic transformation (Middle Palaeolithic s.l.) (Vega-Toscano, 1993). Unit III contains Upper Palaeolithic tools. Units II and I aremainlyNeolithic, with Bronze Age materials in the uppermost Unit I. The bulk of the materials retrieved from Chambers IVand V consists of pottery sherds. In addition, there are blades, numerous items of worked bone, stone, bone and shell beads, shell pendants, schist and shell bracelet fragments, flint sickle blades, silver and gold rings, polished blades, grinding stones, marble and bone idols, bronze daggers, bones of sheep, goat, cattle and pig, and carbonized grains of wheat and barley (Pellicer, 1964a; Wigand, 1978).

Human remains in Units VIII, VI, V, and lowermost levels of Unit IV are attributable to the Neanderthals; and the Units III–I and uppermost beds of Unit IV to anatomically modern man (‘‘Moderns’’) (Garcı´a-Sa´nchez, 1960; Vega-Toscano, 1988). Neanderthal remains include fragments of parietal and frontal bones of both adults and children. Bone remains from Moderns include cranial and tibial fragments during the Pleistocene and a diversity of individual and collective burials during the Neolithic and Bronze Age levels (Fig. 3). Human osteological remains are in fact, abundant in CIV and CV, but unfortunately in most cases severely fractured (Wigand, 1978).

The rest of the paper largely concerns itself with the pollen sequences dating from after the glacial maximum, and makes for some interesting reading, as we learn of how the changing climate altered the arboreal profile of the landscape, which itself became ever more subject to modifications as humans settled the area thorough the Upper Palaeolithic, Chalcolithic, through the Bronze Age via the Neolithic, whilst the earliest recorded dates go back 117,000 years with a 41,000 year margin of error. Comparison of Carihuela is made with another site, Padul, as we see from this:

Like Carihuela, the Padul pollen record includes Eemian and Holocene phases characterized by forested landscapes of oaks and thermophytes, while the main woods during the Pleistocene stages are pines and junipers, which alternate with herbaceous types, eventually Artemisia and Poaceae as main pollen contributors during full-glacial peaks.

Interesting to note that oak trees in the region have been present for over 15,000 years,but even more interesting is the fact that the remains of at least 4 woolly mammoth have also been found in a peat bog at Padul, their and having been carbon-dated to between 35,000 and 25,700 bp, placing these animals much further south than their presumed latitudinal limits as the last glaciation began to exert its influence in the millennia before the glacial maximum.

This new find, though, is more than 300 kilometres (185 miles) farther south, which shows that the grasslands that flourished in the dry, cold climate in the Eurasian ice ages extended much farther south than previously thought.

“These woolly mammoths finds do not belong to stray animals who only chanced to head south, but belonged to Granada’s permanent inhabitants at this time,” said Diego Alvarez-Lao of the University of Oviedo, Spain.

The finds are backed by evidence from drill cores, indicating that steppe plants once flourished in Spain.  The team believe the woolly giants pushed south at the same time as similar advances into eastern China, northern Japan and Kamchatka, a migration associated with climate change in the northeast Atlantic and northwest Pacific.

In addition to the woolly mammoth it is likely that other animals were also squeezed out of northern Europe, and their southern migrations would have helped ensure that supplies of fresh meat remained available to human hunters taking refuge there, both archaic and AMH. For their part the woolly mammoth lived on for maybe 10,000 years after the glacial maximum, but not in Spain, from where they and the Neanderthals have long since disappeared. The fact that some of this fauna also headed East should alert us to the idea that late surviving Neanderthals might also have found their way to further than previously imagined oriental destinations.

As home to the first Europeans and the last Neanderthals, the Iberian peninsular is undoubtedly of unparalleled importance in the context of Pleistocene Europe, and the intense amount of labour and research in recent decades that have thus far been devoted to telling the story of our ancestors is well documented. It therefore seems baffling that the Junta in Andalucía is so out of step with the rest  of the country’s research efforts, and downright mysterious that the Spanish Ministry of Culture is apparently powerless or unwilling to step up, take responsibility and resolve the issue at La Carihuela, especially when we consider the cave has apparently remained closed without credible explanation for over a decade.

Público.es , which also notes there are difficulties at the site of Orce, a find-spot of putative human remains dating back  at least 1.3 million years, quotes the Junta as saying that they don’t wish to respond to the specific allegations about Carihuela raised by the archaeologists, saying further that six other Neanderthal sites are under active investigation, and that research at Carihuela will develop as time goes by – whatever that means. It is to be hoped that encouragement from the outside world will help prompt the authorities in Andalucía into taking the correct decision to allow the archaeologists to re-commence proceedings inside Carihuela at their earliest convenience.

Cited: The Holocene and Upper Pleistocene Pollen Sequence of Carihuela Cave, Southern Spain, (PDF) Santiago Fernández et al, Geobios, Received 21 April 2005; accepted 1 January 2006 Available online 16 January 2007

The Palaeoenvironment of Carihuela Cave (Granada, Spain): A Reconstruction on the Basis of Palynological Investigations of Cave Sediments, José S. Carrión, Manuel Munuera and Cristina Navarro, Review of Palaeobotany and Palynology
Volume 99, Issues 3-4, March 1998, Pages 317-340, doi:10.1016/S0034-6667(97)00040-7

The Padul mammoth finds — On the Southernmost Record of Mammuthus primigenius in Europe and its Southern Spread During the Late Pleistocene, Diego J. Álvarez-Lao, Ralf-Dietrich Kahlke, Nuria García, and Dick Mol, Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 278, Issues 1-4, 15 July 2009, Pages 57-70, doi:10.1016/j.palaeo.2009.04.011

There’s been some coverage of a recent announcement by Svante Pääbo of the Max Planck Institute, who opines that Neanderthals and anatomically modern humans had sexual encounters as they co-habited in Upper Palaeolithic Eurasia from around 42,000 bp to 24,500 bp. The main article is over at the London Times, from which this is an excerpt:

Paabo recently told a conference at the Cold Spring Harbor Laboratory near New York that he was now sure the two species had had sex — but a question remained about how “productive” it had been.  “What I’m really interested in is, did we have children back then and did those children contribute to our variation today?” he said.

“I’m sure that they had sex, but did it give offspring that contributed to us? We will be able to answer quite rigorously with the new [Neanderthal genome] sequence.”  Such an answer might ease the controversy over recent contradictory discoveries regarding Neanderthals. Some fossils seem to have both modern human and Neanderthal features, suggesting that the two species interbred. Yet DNA scans have shown that Neanderthal genes were very different from those of modern man.

Pääbo is reported to be at the point of publishing his analysis of the Neanderthal genome, and it seems clear that he has gleaned something from the data that has prompted this latest assertion; previous research has been interpreted as indicating that if the two species did interbreed it was at a very low level, apparently evidenced by the almost complete lack of a Neanderthal presence in our own genome today.

Gene Expression comments thus:

The way Paabo is couching it, what he has found then seems likely to be evidence that humans who had just expanded Out of Africa contributed to the genomes of Neandertals. In other words, modern human introgression into Neandertals. Of course if the gene flow was from modern human to Neandertals exclusively, then it would be an evolutionary dead end since that lineage went extinct.

In any case, for several decades some fossil-based paleoanthropologists have been claiming that there are “intermediate” individuals in the record which indicate modern human-Neandertal hybridization. Most prominently Erik Trinkaus. If Paabo’s finding becomes more solid, then it seems time to update the probabilities on these sorts of claims based purely on morphology.

The story is taken up at Ad Hominin, where the following opinion is expressed:

Today, most researchers acknowledge that some sexual encounters could have occurred between Neandertals and modern humans. The more interesting question is how common were these encounters and did they leave their mark on the modern gene pool. Undoubtedly, modern humans and Neandertals would have recognised each other as fellow humans but this does not mean that they would have acted humanely to each another.

Countless social and psychological studies have shown humans to have a very strong “us versus them” mentality, that no doubt also existed in our ancestors. It is unlikely that modern humans and Neandertals had an easy relationship. Most sexual encounters that took place between the two were likely opportunistic and probably involved enslavement and rape.

Of course we have absolutely no evidence regarding the circumstances under which these liaisons may have taken place, and I imagine the last sentence of the quote above is obliquely referring to the way in which the indigenous Indian populations of the Americas were almost wiped from the face of the Earth by the tide of white Europeans, who staged one of the most brutal and violent land-grabs in recorded history, as they claimed other peoples’ territories for their own, killing thousands in the process.

However, Upper Palaeolithic Europe was a very different place to the Americas of a few centuries ago, with no centralised governments, mobilised armies, or even slavery, as suggested above. I’m not even sure what the duties of a putative slave in the UP would actually be, or how such a state of affairs could even be enforced. The sheer numbers of humans involved in the theft of native peoples’ lands far eclipsed the populations of Ice Age Europe, so although there might have been competition for land and resources, it would have been on a far smaller scale than in modern times.

Moreover, the technological and cultural gap between Neanderthals and incoming moderns was comparatively narrow, as opined by Professor Chris Stringer of the Natural History Museum in London:

“It’s possible that Neanderthals and humans were genetically incompatible, so they could have interbred but their children would have been less fertile,” said Stringer.  This phenomenon is seen in many other species such as when lions breed with tigers and horses breed with zebras.  “I used to believe Neanderthals were primitive,” said Stringer, “but in the last 10,000-15,000 years before they died out, around 30,000 years ago, Neanderthals were giving their dead complex burials and making tools and jewellery, such as pierced beads, like modern humans.”

The popular notion of inter-species sex, as apparent in the previously quoted post, was that brutish Neanderthal men had their wicked way with anatomically modern women by dragging them behind the nearest bush, reinforcing the old stereotype of rapacious cavemen that has so blighted the way in which our archaic ancestors have been viewed for nigh on 150 years.

Because the population of Europe in the Upper Palaeolithic was probably very low in both modern and archaic communities, contact was likely to have been infrequent – indeed it seems quite possible that members of both species lived entire lifetimes without encountering one another – as Neanderthal numbers began to decline, any encounters would become increasingly rare.

And when moderns and Neanderthals did make primary contact, it could have been under any number of circumstances, some of which may have resulted in violence and death, whilst others might have developed into co-operation, friendship, up to and including, romance and kisses. Yet other encounters might have ended in polite ‘nice-to-meet-you’ handshakes, after which the two species quietly got on with minding their own business, without harbouring any particular feelings for or against their new acquaintances.

As a brief aside, I can’t help but speculate that it might have been easier for Neanderthal women to give birth to inter-species offspring than their AMH counterparts – bearing in mind that Neanderthal babies were more robust, the shape and size of their skulls, even when hybridised, would have made it more difficult for AMH mothers to give birth. A Neanderthal woman who had conceived a child fathered by an AMH male would maybe have found it easier to give birth to the hybridised and possibly smaller baby she was carrying – so should we expect to find that hybridised children conceived by Neanderthal women survived in greater numbers than those conceived by AMH mothers? And how would we then consider the evolutionary social factors that led to relationships between the two species that caused AMH men to bond and breed with Neanderthal women? Such a question may be answered in part from this further quote from Ad Hominin:

The recent announcement by Svante Pääbo that he is sure that Neandertals and modern humans had sex is quite a bold pronouncement coming from a scientist. It raises the question of whether this ascertain is based on some hard evidence they found while sequencing the Neandertal genome. It is possible that if there was some Neandertal genes passed on to the first moderns in Europe, they could have got eliminated from the subsequent gene pool as population sizes fluctuated during the more severe climatic episodes. A more likely scenario is that Pääbo’s team found evidence of modern introgression in the Neandertal genome. In all likelihood the incoming modern humans were more numerous than the Neandertals, thereby absorbing the endemic populations through genetic swamping.

This would seem to reinforce the point that any enforced sex is more likely to have been instigated by incoming AMH males on the female Neanderthal population, if we are to take modern history of human conquest and genocide into account and apply the same mind-set to life 30,000 to 40,000 years ago. But the fact that the both modern and archaic populations may have co-existed in Europe for 10,000-15,000 years at least hints that there was no large-scale or organised species cleansing undertaken by AMH, and it’s quite possible that both they and the Neanderthals behaved a great deal better towards each other than has often been the case in our own recorded histories.

It remains to be seen whether this latest research is able to resolve this question of interbreeding, or whether instead tentative clues will emerge that raise more questions than answers.

See also: Video – Svante Pääbo discussing the Neanderthal Genome Project on YouTube.

Via Reuters:

LONDON (Reuters) – Many prehistoric Australian aboriginals could have outrun world 100 and 200 meters record holder Usain Bolt in modern conditions.

Some Tutsi men in Rwanda exceeded the current world high jump record of 2.45 meters during initiation ceremonies in which they had to jump at least their own height to progress to manhood.

Any Neanderthal woman could have beaten former bodybuilder and current California governor Arnold Schwarzenegger in an arm wrestle.

These and other eye-catching claims are detailed in a book by Australian anthropologist Peter McAllister entitled “Manthropology” and provocatively sub-titled “The Science of the Inadequate Modern Male.”

McAllister sets out his stall in the opening sentence of the prologue…

The subject of bottlenecks in ancient human populations is visited once again, as Amos and Hoffman propose to have found evidence for two such events, one as humans migrated out of Africa and later when a migration event into Pleistocene America occurred across the Bering Strait.

Here’s the abstract of the paper which is freely accessible:

There is a strong consensus that modern humans originated in Africa and moved out to colonize the world approximately 50 000 years ago. During the process of expansion, variability was lost, creating a linear gradient of decreasing diversity with increasing distance from Africa. However, the exact way in which this loss occurred remains somewhat unclear: did it involve one, a few or a continuous series of population bottlenecks? We addressed this by analysing a large published dataset of 783 microsatellite loci genotyped in 53 worldwide populations, using the program ‘Bottleneck’.

Immediately following a sharp population decline, rare alleles are lost faster than heterozygosity, creating a transient excess of heterozygosity relative to allele number, a feature that is used by Bottleneck to infer historical events. We find evidence of two primary events, one ‘out of Africa’ and one placed around the Bering Strait, where an ancient land bridge allowed passage into the Americas. These findings agree well with the regions of the world where the largest founder events might have been expected, but contrast with the apparently smooth gradient of variability that is revealed when current heterozygosity is plotted against distance from Africa.

The researchers suggest that their more detailed approach to investigating the data allows for a more complex picture to emerge, which in the process threw up some unexpected findings, as revealed towards the end of the paper:

Despite these complications, a rather consistent pattern emerges, with evidence of a bottleneck being strongest in the Middle East and in the easternmost East Asian/northernmost American populations. These two locations are as one might expect, but there are two additional features that are less obvious. First, the African populations, although at most loci having low t-values, do provide quite strong and consistent evidence of a bottleneck at the lowest variability loci. As discussed, this may reflect an observation bias in which loci with very low variability in Africa are unusual for some reason other than demography.

An alternative explanation is that these loci still retain the signal of an even more ancient, within-Africa event. This would be consistent with the notion that locus variability is inversely related to the antiquity of the bottleneck signal that is best retained and offers an intriguing hypothesis for future studies. The second feature is the pronounced dip in t-value between Europe/central southern Asia and East Asia. This may simply reflect a null signal between two bottlenecks, but might alternatively indicate some other demographic event such as a period of stasis and population expansion. Again, further work is desirable.

Reference:

Evidence that two main bottleneck events shaped modern human genetic diversity by  W. Amos and  J. I. Hoffman, 2009 – Published online before print October 7, 2009, doi: 10.1098/rspb.2009.1473

via Science Daily:

ScienceDaily (Oct. 1, 2009) — In a special issue of Science, an international team of scientists has for the first time thoroughly described Ardipithecus ramidus, a hominid species that lived 4.4 million years ago in what is now Ethiopia.

This research, in the form of 11 detailed papers and more general summaries, will appear in the journal’s 2 October 2009 issue. Science is published by AAAS, the nonprofit science society.

This package of research offers the first comprehensive, peer-reviewed description of the Ardipithecus fossils, which include a partial skeleton of a female, nicknamed “Ardi.”

The last common ancestor shared by humans and chimpanzees is thought to have lived six or more million years ago. Though Ardipithecus is not itself this last common ancestor, it likely shared many of this ancestor’s characteristics. For comparison, Ardipithecus is more than a million years older than the “Lucy” female partial skeleton of Australopithecus afarensis. Until the discovery of the new Ardipithecus remains, the fossil record contained scant evidence of other hominids older than Australopithecus…

National Geographic has more info and images.

October 2nd 2009 Cover of Science Magazine

There’s more than 11 citations here, but the others are associated news and media covered by Science. They’ve even dedicated a special issue to it. Very impressive thorough volume of information. Now you have a some understanding why it took so long to publish… Anyways get to reading.

News Focus

Gibbons, A. (2009). A New Kind of Ancestor: Ardipithecus Unveiled Science, 326 (5949), 36-40 DOI: 10.1126/science.326_36

Gibbons, A. (2009). Habitat for Humanity Science, 326 (5949), 40-40 DOI: 10.1126/science.326_40

Gibbons, A. (2009). The View From Afar Science, 326 (5949), 41-43 DOI: 10.1126/science.326_41

Introduction & Video

Hanson, B. (2009). Light on the Origin of Man Science, 326 (5949), 60-61 DOI: 10.1126/science.326_60a

N/A (2009). Video: The Analysis of Ardipithecus ramidus–One of the Earliest Known Hominids Science, 326 (5949), 60-60 DOI: 10.1126/science.326_60b

Research Articles

White, T., Asfaw, B., Beyene, Y., Haile-Selassie, Y., Lovejoy, C., Suwa, G., & WoldeGabriel, G. (2009). Ardipithecus ramidus and the Paleobiology of Early Hominids Science, 326 (5949), 64-64 DOI: 10.1126/science.1175802

WoldeGabriel, G., Ambrose, S., Barboni, D., Bonnefille, R., Bremond, L., Currie, B., DeGusta, D., Hart, W., Murray, A., Renne, P., Jolly-Saad, M., Stewart, K., & White, T. (2009). The Geological, Isotopic, Botanical, Invertebrate, and Lower Vertebrate Surroundings of Ardipithecus ramidus Science, 326 (5949), 65-65 DOI: 10.1126/science.1175817

Louchart, A., Wesselman, H., Blumenschine, R., Hlusko, L., Njau, J., Black, M., Asnake, M., & White, T. (2009). Taphonomic, Avian, and Small-Vertebrate Indicators of Ardipithecus ramidus Habitat Science, 326 (5949), 66-66 DOI: 10.1126/science.1175823

White, T., Ambrose, S., Suwa, G., Su, D., DeGusta, D., Bernor, R., Boisserie, J., Brunet, M., Delson, E., Frost, S., Garcia, N., Giaourtsakis, I., Haile-Selassie, Y., Howell, F., Lehmann, T., Likius, A., Pehlevan, C., Saegusa, H., Semprebon, G., Teaford, M., & Vrba, E. (2009). Macrovertebrate Paleontology and the Pliocene Habitat of Ardipithecus ramidus Science, 326 (5949), 67-67 DOI: 10.1126/science.1175822

Suwa, G., Asfaw, B., Kono, R., Kubo, D., Lovejoy, C., & White, T. (2009). The Ardipithecus ramidus Skull and Its Implications for Hominid Origins Science, 326 (5949), 68-68 DOI: 10.1126/science.1175825

Suwa, G., Kono, R., Simpson, S., Asfaw, B., Lovejoy, C., & White, T. (2009). Paleobiological Implications of the Ardipithecus ramidus Dentition Science, 326 (5949), 69-69 DOI: 10.1126/science.1175824

Lovejoy, C., Simpson, S., White, T., Asfaw, B., & Suwa, G. (2009). Careful Climbing in the Miocene: The Forelimbs of Ardipithecus ramidus and Humans Are Primitive Science, 326 (5949), 70-70 DOI: 10.1126/science.1175827

Lovejoy, C., Suwa, G., Spurlock, L., Asfaw, B., & White, T. (2009). The Pelvis and Femur of Ardipithecus ramidus: The Emergence of Upright Walking Science, 326 (5949), 71-71 DOI: 10.1126/science.1175831

Lovejoy, C., Latimer, B., Suwa, G., Asfaw, B., & White, T. (2009). Combining Prehension and Propulsion: The Foot of Ardipithecus ramidus Science, 326 (5949), 72-72 DOI: 10.1126/science.1175832

Lovejoy, C., Suwa, G., Simpson, S., Matternes, J., & White, T. (2009). The Great Divides: Ardipithecus ramidus Reveals the Postcrania of Our Last Common Ancestors with African Apes Science, 326 (5949), 73-73 DOI: 10.1126/science.1175833

Lovejoy, C. (2009). Reexamining Human Origins in Light of Ardipithecus ramidus Science, 326 (5949), 74-74 DOI: 10.1126/science.1175834

Ardipithecus ramidus

I want to be the first to break news to you that Science has published White’s contentious 4.4-million-year-old Ardipithecus ramidus! I caught news of the release on the internet. The link is not live yet, but when it is I’ll fill you in.

Owen Lovejoy is one of the authors of the paper, and he says that the fossil changes the notion that humans and chimps, our closest genetic cousins, both trace their lineage to a creature that was more like today’s chimp and we’ll have to be rewriting our text books soon. This is big folks. What this means is that our common ancestor was a bipedal forest forager and that chimps were an evolutionary offshoot.

White, the lead author, describes the fossil with flexible hands and a brain about a quarter the size of a human’s,

“We can’t say this species was a direct ancestor of modern humans, so we have to be careful. But it suggests that the direction of early hominids was away from the chimp.”

There are a lot of other implications that I won’t get into just yet, but keep checking us out from time to time as we get more!

Here are some of the press releases/news coverage that have come out since I’ve published this post:

• Kent State University Professor C. Owen Lovejoy helps unveil oldest hominid skeleton
• Fossil finds extend human story
• Before ‘Lucy,’ there was ‘Ardi’: First major analysis of early hominid published in Science
• Oldest hominid skeleton provides new evidence for human evolution
• Humanity Has a New 4.4 Million-Year-Old Baby Mama
• Ancient Skeleton May Rewrite Earliest Chapter of Human Evolution
• Fossil Skeleton From Africa Predates Lucy
• Ethiopian desert yields oldest hominid skeleton
• Ardi displaces Lucy as oldest hominid skeleton
• Fossil Primate Ardipithecus Ramidus Described (Finally)
• Oldest “Human” Skeleton Found–Disproves “Missing Link”
• ‘Ardi,’ Oldest Human Ancestor, Unveiled

There’s a very interesting new paper, through which prospective readers are free to roam and explore at will, by Alfonso Arribas et al, in which the site of Fonelas, Granada in southern Spain is described, where excavations have revealed that around 1.8 million years ago, a vast suite of mammalian fauna from Asia, Europe and Africa congregated, affording us a unique glimpse into a previously hidden corner of the world at a time when the first hominids are thought to have made their appearance on the European stage. Moreover, these findings will prompt a great deal of thought as to how and why large mammals from such discrete and distant geographical locations came to occupy an area known today as the Guadix Basin, part of the Betic Cordillera. By way of a more formal introduction, here’s the abstract:

Background

Over the last decades, there has been an increasing interest on the chronology, distribution and mammal taxonomy (including hominins) related with the faunal turnovers that took place around the Pliocene-Pleistocene transition [ca. 1.8 mega-annum (Ma)] in Europe. However, these turnovers are not fully understood due to: the precarious nature of the period’s fossil record; the “non-coexistence” in this record of many of the species involved; and the enormous geographical area encompassed. This palaeontological information gap can now be in part bridged with data from the Fonelas P-1 site (Granada, Spain), whose faunal composition and late Upper Pliocene date shed light on some of the problems concerning the timing and geography of the dispersals.

Methodology/Principal Findings

This rich fossil site yielded 32 species of mammals, among which autochthonous species of the European Upper Villafranchian coexist with canids (Canis), ovibovines (Praeovibos) and giraffids (Mitilanotherium) from Asia. Typical African species, such as the brown hyena (Hyaena brunnea) and the bush pig (Potamochoerus) are also present.

Conclusions/Significance

This assemblage is taxonomically and palaeobiogeographically unique, and suggests that fewer dispersal events than was previously thought (possibly only one close to 2.0 Ma) are responsible for the changes seen around 1.9–1.7 Ma ago in the fauna of the two continents.

The site at Fonelas itself has been described previously in 2006, (PDF), and this paper follows on from research published in 2007, reported at this very site, the BBC and elsewhere, whilst there is even a dedicated website, in Spanish, and the sheer number and density of the fossils found are in large part due to the scavenging activities of ancient hyena. However to bring us up to date, here’s another brief snippet from the opening paragraphs:

Lying within the western extreme of the Palaearctic, the Iberian Peninsula is known for palaeoenvironmental sites with evolutionary implications of paramount importance. Over long periods of geological time, this has been a land of transitions and physiographical heterogeneity, including the possible existence of islands in the Straits of Gibraltar (enabling exchanges with the African continent). Conceivably, throughout the Cenozoic, climatically influenced species turnover, invasions, and competitive exclusion combined with species survival produced unique associations of plant and animal species. Here, we report on the chronology and composition of the late Upper Pliocene Fonelas P-1 fossil assemblage. Analogous assemblages have not been documented in Eurasia and no other findings have been recovered in the Quaternary. This truly is a large mammal “Lost World”.

The finds seem to mostly date from 1.8 million years, a date traditionally ascribed to the Pliocene/Pleistocene boundary, also known as the Quaternary, (preceded by the Neogene) but as was reported recently, this boundary which describes the onset of global cooling which ushered in a series of intense glaciation episodes, has recently been officially re-dated some 800,000 years beforehand to 2.6 mya. This is because it was felt that the earlier date more accurately reflects the time when global cooling commenced, and moreover is opined to be of greater significance in the geological record.

The paper itself offers a graphic description of the site itself, of which only a tiny portion has thus far been excavated, and includes details of the various mammals which made their way to the Iberian peninsular,  in what the researchers believe was a single migration event. Of particular interest is how some of these mammals made their way from Africa, and owing to a lack of finds along the Levantine, they propose that the Strait of Gibraltar may have been a crossing point between the African and European continents.

Although there is speculation that island once existed there that would have allowed for such a crossing, there is no evidence that I could find in the geological record that any such islands existed  – presumably the mammals, including early Homo, would have swum between each of these putative islands, some heading north into Europe, others heading south into Africa, in a faunal (and floral) exchange.

It occurred to me that there may have been episodic freezing of the Strait, which would allow for a much neater and tidier fit than transient islands, or even a land bridge which would have had to be in existence long after the Messinian salinity crisis around 5.9 million years ago, the last time that the flow of water into and out of the Med from the Atlantic had been blocked. The result was that the Med evaporated in around 1,000 years, with the possible exception of a few briny lakes scattered across the abyssal floor.

However, the sheer volume of water flowing through the Strait in both directions would seem to dictate that the Strait would not have frozen, even on a more contrasted seasonal basis,  around the time of the glaciation in Europe around 1.8 million years ago – something would have needed to temporarily switch off the Atlantic current, whose reduced salinity would have been more prone to freezing. But these strong currents would also have been a major problem for terrestrial mammals attempting the crossing, with or without islands dotted here and there, and would therefore have presented a formidable obstacle.

However, I can find no evidence that even hints at the Strait freezing over at that time, or indeed ever, and although it might be possible that a very brief episode of (seasonal) freezing lasting only decades occurred around 1.8 mya, there might be no clues in the geologic records that could confirm or deny this. The southerly latitude of the Strait is far from the Alpine glaciation which occurred further north in Europe, and even in the recent glaciation, it is thought that icebergs were found no further south than the Bay of Biscay, which again would seem to argue against the southern Iberian peninsular being cold enough to freeze its coastal waters.

If there had been islands or a land bridge at the time, the flow of water from the Atlantic could have been severely restricted, possibly to the extent that sea levels in the Med would have fallen, as the outflow of rivers around the Med Basin isn’t enough to keep it topped up. But a thin ice sheet across the Strait of Gibraltar may have allowed enough water from the Atlantic to continue flowing into the Med without compromising the depth therein – allowing for this mysterious exchange of flora and fauna which later inhabited the ‘lost world’ of the Guadix Basin.

There’s plenty more in this paper worth checking out, most notably about how the dating was established, and the details of the impressive number of remains discovered, and it seems likely that future seasons of digging  and analysis will offer an even greater volume of data and further establish the Iberian peninsular as a unique location for establishing its importance in the search for ever clearer insights into the first archaic humans residents of Europe and the vast suite of mammalian fauna with whom they co-habited.

References: Arribas A, Garrido G, Viseras C, Soria JM, Pla S, et al. (2009) A Mammalian Lost World in Southwest Europe during the Late Pliocene. PLoS ONE 4(9): e7127. doi:10.1371/journal.pone.0007127

César Viserasa, Jesús M. Soriab, Juan J. Duránc, Sila Plaa, c, Guiomar Garridoc, Fernando García-Garcíad and Alfonso Arribasc (2006) A large-mammal site in a meandering fluvial context (Fonelas P-1, Late Pliocene, Guadix Basin, Spain) Sedimentological keys for its paleoenvironmental reconstruction (PDF)

Palaeogeography, Palaeoclimatology, Palaeoecology
Volume 242, Issues 3-4, 8 December 2006, Pages 139-168

doi:10.1016/j.palaeo.2006.05.013

The latest issue of the Proceedings from the National Academy of Science journal hosts a Out of Africa: Modern Human Origins special feature for free online. I recommend you check it out.

September 22nd, 2009 Cover of the PNAS Out of Africa: Modern Human Origins Special

• Editorial by Richard G. Klein, “Darwin and the recent African origin of modern humans.”
• Perspective by Ian Tattersall, “Human origins: Out of Africa.”
• Perspective by Timothy D. Weaver, “The meaning of Neandertal skeletal morphology.”
• Research Article by J. J. Hublin, “The origin of Neandertals.”
• Research Article by Michael P. Richards and Erik Trinkaus, “Isotopic evidence for the diets of European Neanderthals and early modern humans.”
• Research Article by John F. Hoffecker, “The spread of modern humans in Europe.”
• Research Article by G. Philip Rightmire, “Middle and later Pleistocene hominins in Africa and Southwest Asia.”
• Research Article by Francesco d’Errico, et al., “Additional evidence on the use of personal ornaments in the Middle Paleolithic of North Africa.”
• Research Article by Michael DeGiorgio, et al.,”Explaining worldwide patterns of human genetic variation using a coalescent-based serial founder model of migration outward from Africa.”

Unfortunately, I have not yet had the time to read any of these papers but they I reckon they should be somewhat enlightening.

Although this is as yet only a provisional paper, and I don’t know what, if any revisions will be made, it nevertheless makes several notable observations. It’s free to access, and begins as follows:

Abstract (provisional)

Background

In this study, we used genetic data that we collected in Central Asia, in addition to data from the literature, to understand better the origins of Central Asian groups at a fine-grained scale, and to assess how ethnicity influences the shaping of genetic differences in the human species. We assess the levels of genetic differentiation between ethnic groups on one hand and between populations of the same ethnic group on the other hand with mitochondrial and Ychromosomal data from several populations per ethnic group from the two major linguistic groups in Central Asia.

Results

Our results show that there are more differences between populations of the same ethnic group than between ethnic groups for the Y chromosome, whereas the opposite is observed for mtDNA in the Turkic group. This is not the case for Tajik populations belonging to the Indo-Iranian group where the mtDNA like the Y-chomosomal differentiation is also significant between populations within this ethnic group. Further, the Y-chromosomal analysis of genetic differentiation between populations belonging to the same ethnic group gives some estimation of the minimal age of these ethnic groups. This value is significantly higher than what is known from historical records for two of the groups and lends support to Barth’s hypothesis by indicating that ethnicity, at least for these two groups, should be seen as a constructed social system maintaining genetic boundaries with other ethnic groups, rather than the outcome of common genetic ancestry

Conclusions

Our analysis of uniparental markers highlights in Central Asia the differences between Turkic and Indo-Iranian populations in their sex-specific differentiation and shows good congruence with anthropological data.

Reference: Evelyne Heyer, Patricia Balaresque, Mark A Jobling, Lluis Quintana-Murci, Raphaelle Chaix, Laure Segurel, Almaz Aldashev and Tanya Hegay. Genetic diversity and the emergence of ethnic groups in Central Asia. BMC Genetics, 2009; (in press) [link]

The current issue of the Journal of Neurodevelopmental Disorders has published an open access paper announcing the discovery of a new candidate gene linked to language, KIAA0319. The paper is titled, “Convergent genetic linkage and associations to language, speech and reading measures in families of probands with Specific Language Impairment.”

The gene sits on short arm of Chromosome 6. Through linkage analysis, it was found to be associated with variability in language abilities in a study of children with Specific Language Impairment (SLI) and their family members, as well as with variability in speech and reading abilities. Specific alleles were confirmed with association analysis.

“A total of 322 participants, including 86 probands, 134 siblings, and 102 parents and other relatives were tested from an ongoing longitudinal study of Specific Language Impairment… The significant results cluster in the 5’ region of KIAA0319… In particular, we replicate the associated alleles for rs4504469 (allele C); rs761100 (allele G); rs6935076 (allele T) and rs3756821 (allele A).”

It should be noted that KIAA0319 was already linked to dyslexia in previous studies. But, in this paper, the pleiotropic effects of KIAA0318 alleles on language ability, speech impairments, and text comprehension were correlated.

Rice, M., Smith, S., & Gayán, J. (2009). Convergent genetic linkage and associations to language, speech and reading measures in families of probands with Specific Language Impairment Journal of Neurodevelopmental Disorders DOI: 10.1007/s11689-009-9031-x

Speaking of the Johansons and fossils …

Earlier this year, I’ve blogged about the 2009 Human Evolution Leakey Symposium at Stony Brook that I went to. For more about that blog post, click here.

The symposium, entitled “Hobbit in the Haystack: Homo floresiensis and Human Evolution” can now be streamed live through the Stony Brook website. The website also includes previous Human Evolution Leakey symposia. Click here to watch.

Thanks to Afarensis: Anthropology, Evolution and Science for the heads up!

Originally posted on The Prancing Papio

Here’s the abstract to a newly published paper, the contents of which are free to access:

There is an ongoing discussion in the literature on whether human mitochondrial DNA (mtDNA) evolves neutrally. There have been previous claims for natural selection on human mtDNA based on an excess of non-synonymous mutations and higher evolutionary persistence of specific mitochondrial mutations in Arctic populations.

However, these findings were not supported by the reanalysis of larger datasets. Using a geographical framework, we perform the first direct test of the relative extent to which climate and past demography have shaped the current spatial distribution of mtDNA sequences worldwide. We show that populations living in colder environments have lower mitochondrial diversity and that the genetic differentiation between pairs of populations correlates with difference in temperature. These associations were unique to mtDNA; we could not find a similar pattern in any other genetic marker.

We were able to identify two correlated non-synonymous point mutations in the ND3 and ATP6 genes characterized by a clear association with temperature, which appear to be plausible targets of natural selection producing the association with climate. The same mutations have been previously shown to be associated with variation in mitochondrial pH and calcium dynamics. Our results indicate that natural selection mediated by climate has contributed to shape the current distribution of mtDNA sequences in humans.

Reference: Climate shaped the worldwide distribution of human mitochondrial DNA sequence variation by François Balloux, Lori-Jayne Lawson Handley, Thibaut Jombart, Hua Liu and Andrea Manica,

Published online before print July 8, 2009, doi: 10.1098/rspb.2009.0752

Scientific American recently published a spineless attack on the state of access to paleoanthropological specimens. They titled it, “Fossils for All: Science Suffers by Hoarding,” and John Hawks lend it credibility with a nod in his post. Aside from being spineless, it reeks of ignorance and is tactless. In this post I’ll be discussing why this is not a honest criticism but rather a sloppy slam.

If you read the piece, you’ll notice that Tim White is in the cross hairs of the editors of Scientific American. Why? Tim White discovered Ardi­pithecus ramidus fifteen years ago and continues preparing the specimens. For the editors, that’s enough to pull the guns out and start shooting — claiming he’s sitting on his golden egg far too long and damaging the field as a whole. The cowards at Scientifc American decided to make this bold claim behind a wall of anonymity… publishing this piece simply as the editors. And here in lies the drama and the conflicts of interest.

See, most anthropological editorials on Scientific American are authored by Kate Wong, a twelve year veteran editor for magazine. She is their anthropology editor. Her authority on the subject matter come from a Bachelor’s degree in physical anthropology and zoology from the University of Michigan. University of Michigan is home to Milford Wolpoff, the man who supports multiregional evolution hypothesis… You know the one that claims the origins of Homo sapiens happened in multiple places around the world and not from a common African origin. He’s known for not being a field scientist. Furthermore, within the discipline, the rift between Wolpoff and White is pretty well known and deep. White got his PhD from the University of Michigan. And Wolpoff holds a ~50 year grudge against White in regards to his stance against his single species origin of humans.

Wong has worked closely with another large anti-Tim White camp, the Hadar folks, during the lead up to the Selam news frenzy that we talked about several years ago. The Hadar camp is more or less a Donald Johanson territory as he was there when Lucy was discovered and published the findings. Where Wong may not have an immediate connection to Wolpoff, aside from earning her Bachelor’s from the department Wolpoff teaches in, she does have a clear one with Johanson. She was a coauthor with Donald Johanson on a book published this year, Lucy’s Legacy.

As you may know, there’s also sour grapes shared shared between Johanson and White. I won’t get into those details… But its clearly out there and is exemplified by a passage in Lucy’s Legacy,

“Tim is a very exacting scientist who is not about to be pressured into saying more about ramidus until he is good and ready. But his unwillingness to share more information about the fossils – not to mention access to the remains themselves – in a much more timely way has drawn criticism. (So secretive are he and his team about the fossil that it has been referred to as the Manhattan Project of paleoanthropology.) In fact, spurred in part by Tim’s actions, some researchers have even proposed that funding agencies such as the National Science Foundation establish a limitation on how long the discoverer of a fossil has exclusive access to that material before having to share it with other investigators.” p. 155-156 Lucy’s Legacy

There’s no way to know if Johanson or Wong wrote this particular passage but they both share authorship and royalities of the book and ultimately agree on the points raised in the text.

This is a clear conflict of interest for Scientific American and their anthropological editor, Kate Wong. As an editor of Scientific American, for Wong to be an author of a book which conveys the same criticisms as published under anonymity in their magazine and on their website, shows that she exploited her professional capacity for personal benefit.

In addition to egregious political move by Scientific American, the piece is ignorant of the whole process involved in finding, cleaning, documenting a fossil. Fossils don’t come out of the ground perfect. Believe me, I know. Some of the time these findings are as delicate as a ball of dust and require a great deal of care to preserve them during which time it is the primary investigator/discoverer’s responsibility and privilege.  I’ve actually discussed this before, very thoroughly in this comment thread.

For the editors and other supporters to suggest there should be a limit to how long it takes to prepare a fossil show how they really have no idea to what it takes to curate a fossil. There’s no way to put a time limit on this process. Aside from a select few, most field scientists are professors at universities. Again, as I’ve said before, their time in the field is limited, several months a year, of which time is split between finding new fossils and curating old ones. Field scientists, like White, can’t leave their teaching positions at places like UC Berkeley and dedicate years to preparing the specimen. They do as much as they can and they do it with quality. The Middle Awash, White’s stomping ground, has an impressive record of impactful, frequent fossil discoveries and publications which can’t really be said for Wolpoff and Johanson.

You may consider this a defense of White. I admit this is. This was a shameless jab at White and a despicable, cowardly, and haphazard move by Scientific American. Science is not about quantity. I shouldn’t have to tell freaking Scientific American that. Science is about quality. Editorials like this don’t advance the field. They completely ignore that science is a process and not a product. In doing so they damage the discipline.

One last thing… To the editors of Scientific American, grow some balls next time you wanna put out crap like this and publish your full names along side your criticism. Stand behind your words.

Abstract: Variation is one of the most important phenomena occurring in humans, and is attributed to many factors such as mutation and natural selection. Many studies have emphasized the importance of anthropometric measurements as a means of studying variation in human populations as well as a veritable tool in forensic science for crime detection. This study investigates the nasal breadth, nasal length and nasal indices of individuals of Itsekiri and Urhobo ethnic extraction, as a baseline study which may be necessary for future reference in these regard. Nasal length and nasal breadth of 1000 living Itsekiri and Urhobo people, aged 25-45 years, were measured. From these data, nasal indices were calculated and results were compared with published standards for various world populations. The results showed that on the average, the Urhobos had a mean nasal index of 89.63 and the Itsekiri’s had a mean nasal index of 90.74. Sexual dimorphism was also observed in the ethnic groups studied with males having significantly higher nasal index values than the females (p < 0.05). Therefore, the two ethnic groups fall within the same nose type which is platyrrhine (short and broad nosed) expected of an African population. The findings of this study have confirmed anthropological differences amongst the two Nigerian ethnic groups examined.

Full study: link.

Here’s a link to a recent paper published by Michael Richards and Erik Trinkaus, in which they propose that isotopic analyses of early modern human remains indicate a broader dietary range than Neanderthals, with the specific suggestion that European EMH supplemented their food intake with items such as freshwater fish, whilst European Neanderthals obtained almost all their meat from herbivores. Here’s the abstract:

We report here on the direct isotopic evidence for Neanderthal and early modern human diets in Europe. Isotopic methods indicate the sources of dietary protein over many years of life, and show that Neanderthals had a similar diet through time (≈120,000 to ≈37,000 cal BP) and in different regions of Europe. The isotopic evidence indicates that in all cases Neanderthals were top-level carnivores and obtained all, or most, of their dietary protein from large herbivores. In contrast, early modern humans (≈40,000 to ≈27,000 cal BP) exhibited a wider range of isotopic values, and a number of individuals had evidence for the consumption of aquatic (marine and freshwater) resources. This pattern includes Oase 1, the oldest directly dated modern human in Europe (≈40,000 cal BP) with the highest nitrogen isotope value of all of the humans studied, likely because of freshwater fish consumption. As Oase 1 was close in time to the last Neanderthals, these data may indicate a significant dietary shift associated with the changing population dynamics of modern human emergence in Europe.

The rest of the paper is available here as a PDF.

Reference: Published online before print August 11, 2009, doi: 10.1073/pnas.0903821106 Isotopic Evidence for the Diets of European Neanderthals and Early Modern Humans by Michael P. Richards and  Erik Trinkaus

Link

I’ll be away from my desk for another week or so yet, but in the meantime here’s a quick heads-up to a programme airing in the US on the National Geographic Channel, on Sunday August 30th at 9 pm ET/PT, of which this is a brief description from NGC:

On a single day on a single street, with the DNA of just a couple of hundred random people, National Geographic Channel sets out to trace the ancestral footsteps of all humanity. Narrated by Kevin Bacon, The Human Family Tree travels to one of the most diverse corners of the world — Queens, N.Y. — to demonstrate how we all share common ancestors who embarked on very different journeys. Regardless of race, nationality or religion, all of us can trace our ancient origin back to the cradle of humanity, East Africa. What did our collective journey look like, and where did it take your specific ancestors? At what point in our past did we first cross paths with the supposed strangers living in our neighborhood? Now, in The Human Family Tree, the people of this quintessential American melting pot find out that their connections go much deeper than a common ZIP code.

There’s a video teaser, “Human Family Tree – Preview” – By studying the DNA of random people on a New York street, scientists prove we are all cousins in the family of man, and another video clip offers an insight into the origins of the First Americans.

Mention too is made to the Hadzabe tribe of Tanzania, as we see from this:

Hollowed Baobab tree trunks are traditionally used as places where Hadzabe give birth. The Hadzabe, who live about 15-hundred miles north of the San near Tanzania’s Serengeti, represent one of the first branches in the human family tree. They split from the founding population (the San) around 150,000 years ago. Today the Hadzabe are one of the last groups of hunter-gatherers on Earth.

The image at top depicts just such a Baobab tree. (photo credit © NGT/Chad Cohen).

Moreover, there are many other features at the dedicated site, whereby readers can:

* Meet the participants featured in Human Family Tree.     * Meet Spencer Wells, Director of the Genographic Project.     * Learn more about the Genographic Project, and get the latest updates from the Project Team.     * Check out the Time Line of Human Migration and interact with the Atlas of the Human Journey.     * Get the facts about our ancient ancestors.

As I’m blogging this via an internet cafe, I haven’t the time or battery life right now to check out all these features, but I hope nevertheless they will be of interest to all online, and hopefully the programme itself, airing only in the US, will become available in Europe at some later date.

New analysis by a team led by Australian National University doctoral student Debbie Argue showed that Homo floresiensis, nicknamed hobbits, were early hominin and walked out of Africa to Flores. Their findings supports the argument that Homo floresiensis had a unique wrist anatomy that originated from a lineage that lived long before the common ancestor of Homo sapiens and Neanderthals.

With Mike Moorwood from University of Wollongong and Thomas Sutikna from Indonesian Center for Archaeology, Debbie Argue compared 60 skulls and skeletal features from two individual hobbits to those of hominins, chimpanzees and gorillas using cladistic analysis. The result shows that Homo floresiensis “probably took one of two evolutionary paths from Africa to Flores. One began 1.66 million years ago, the other 1.9 million years ago”.

Read more here: Hobbits Walked Out of Africa

Originally posted on The Prancing Papio.