archaeology

If you have a subscription to Nature, you can get a short story from last week's issue, which explores the reaction of a couple of genetics-types to finding Neandertal genes responsible for human mental abilities:

That has to be interbreeding. The earlier studies had missed it because they hadn't considered the changing impact of natural selection over time."

"You can back that up?"

"Absolutely." Beth was always meticulous about her data.

I didn't have to force a smile. "That's fascinating," I said. "It will make Nature for sure." It would get a lot of people hot under their collective collars, but that was fine. Evidence of interbreeding with Neanderthals would create a new paradigm for hybridization being behind the rapid advance of modern humans and make me famous. "What genes are involved?"

Notice: you can tell this is fiction because the result "will make Nature for sure"!

On the other hand, some parts are uncomfortably true-to-life:

"I'm a scientist. I want to know the truth!" More importantly, I wanted to finish the contract; that was my job as principal investigator. I'd always succeeded before; that was why after two decades at the university I was department chair and Beth was still a research assistant.

Yes, the plucky female scientist who believes in the Neandertals is passed over for advancement, while the overbearing man who cares only about grant applications runs the whole department. Well, try to tell me that part is fictional!

It's not that great a story, but the surprise conclusion is exactly what we've been writing -- some aspects of today's human brain biology probably reflect the genetic interactions between Pleistocene human populations. It's neither shocking nor surprising. It's simply evolution!

References:

Hecht J. 2008. The Neanderthal correlation. Nature 453:562. doi:10.1038/453562a

Well, archaeology is set to receive a once-in-a-generation influx of interest from teenagers drawn to the allure of the past. I mean, from the new Indiana Jones movie, of course.

So what do they have to go and do? Discover a real life crystal skull? Sorry, kids. If you want to be an archaeologist, it's all bodily functions from here on out.

Tom Dillehay and colleagues (2008) report in this week's Science that they have found chewed-on seaweed "cud" from Monte Verde, dated to 14,000 calendar years BP. And that paper is right next to the final publication of the Paisley Caves coprolites from Oregon, also dating to slightly before 14,000 calendar years BP.

Both papers are pretty cool -- together they emphasize that these kinds of forensic evidence are becoming increasingly important in documenting the activities (and existence) of archaeological populations. After all, a person has to poop thousands of times during his life, but he has only one skeleton.

Dillehay and colleagues interpret their seaweeds as a specialized medicinal collection, based on the presence of non-edible species and species present at different times of the year. Here's a quote from Michael Balter's news piece on the find:

Back 14,000 years ago, Monte Verde was located about 90 kilometers east of the sandy Pacific coast and 15 kilometers north of a rocky-shored inland marine bay. Algae from both environments were recovered, including inedible species that are today used as medicines in Chile and elsewhere. Moreover, the algal species found are known to flourish at different times of the year, suggesting to Dillehay's team that the Monte Verdeans were intimately familiar with coastal resources--possibly because they had originally arrived in the region via that route. Erlandson agrees: "The variety of seaweeds implies a pretty deep knowledge of coastal ecosystems and a long history of exploiting them."

Well, that's pretty impressive, even if the seaweed were chewed up. And hey, my kids are much more interested in bodily functions than they are in crystal skulls. So maybe this will bring in new archaeologists after all!

References:

Balter M. 2008. Ancient algae suggest sea route for first Americans. Science 320:729. doi:10.1126/science.320.5877.729

Dillehay TD, Ramírez C, Pino M, Collins MB, Rossen J, Pino-Navarro JD. 2008. Monte Verde: Seaweed, food, medicine, and the peopling of South America. Science 320:784-786. doi:10.1126/science.1156533

Gilbert MTP and 12 others. DNA from pre-Clovis human coprolites in Oregon, North America. Science 320:786-789. doi:10.1126/science.1154116

In case you needed a reminder that much of the territory occupied by Pleistocene humans is now beneath the waves, just take a look at this press release from the British archaeology company Wessex Archaeology:

An amazing collection of 28 flint hand-axes, dated by archaeologists to be around 100,000 years-old, have been unearthed in gravel from a licensed marine aggregate dredging area 13km off Great Yarmouth.

The find was made by a Dutch amateur archaeologist, Jan Meulmeester, who regularly searches for mammoth bones and fossils in marine sand and gravel delivered by British construction materials supplier Hanson to a Dutch wharf at Flushing, near Antwerp, south west Netherlands.

The axes show that deep in the Ice Age, mammoth hunters roamed across land that is now submerged beneath the sea. These are the finest hand-axes that experts are certain come from English waters, although there have been a few finds on beaches, for example at Pakefield in Suffolk.

As a result of the find, they moved the dredging operation to conform with regulations -- I suppose to preserve the site in case the sea level falls!

It seems to me that these are likely to predate 100,000 years ago, but no date is really possible given the circumstances.

This isn't the first such find. Werz and Flemming (2001) reported the separate discoveries of three quartzite bifaces during shipwreck archaeology in Table Bay, South Africa. Again these are undated but probably precede 300,000 years ago. Finds of artifacts from the later stages of the Paleolithic have been more common.

References:

Werz BEJS, Flemming NC. 2001. Discovery in Table Bay of the oldest handaxes yet found underwater demonstrates preservation of hominid artefacts on the continental shelf. S Afr J Sci 97:183-185.

I just read a good popular article by Colin Woodard about the 15th-century decline of the Greenland Norse.

"During the same time period, a lot of Norse settlements in Iceland and northern Norway were being abandoned, but nobody writes big books about that," [forensic anthropologist Niels] Lynnerup says. "I'm not sure that the Norse saw Greenland as being very different from the fjords they came from in Norway, and leaving it was no more stressful than abandoning a hamlet in Norway." His theory: In the 1300s and 1400s, Greenland's youths voted with their feet, leaving until the colony could no longer support itself. The last few left.

You may have seen some of this stuff before -- I think there has been a television special about it -- but it's a nice summary of what forensic anthropologists and others have been up to in southern Greenland, complete with analyses of livestock parasites.

I'm pointing to the article because of this line:

Did the Norse colonists starve? Were they wiped out by the Inuit - or did they intermarry? No. Things got colder and they left.

This is what I always keep in mind when I'm reading about "climate change killing the Neandertals" and whatnot. Human movements are fast. Hunter-gatherer migration is potentially much faster than migration of sedentary agriculturalists. In the archaeological record, we are not looking at migrations, we are looking at long-term fluctuations in the pattern of short-term, rapid movements.

There is no great dramatic moment. For the Norse, it looks like there were several bad winters. As the story relates, some people died, but most left.

The possible difference in the Neandertal case is the vastly longer timescale, which may have allowed a much greater cultural shift. It looks like the Norse did not mate with the indigenous Inuit in a way that left a lot of genes behind in Greenland natives. Their culture never adopted elements of Inuit subsistence technology that might have worked for them. Neandertals had longer to adjust -- and there were possibly fewer technological differences between them and their contemporaries in the first place. Cultural interactions seem to have occurred, and we can imagine mating would have also.

But in the end, climate change in Europe 35,000 years ago really amounted to a long run of bad winters. The people should have moved. They did move. Whoever was making Mousterian tools eventually stopped. As to what else happened, we have to rely on comparisons of other, later samples.

UPDATE (2007/01/06): A reader writes:

There is, of course, another comparison, the ESKIMO populations, who did not become extinct, or were even affected.  The Norse were too arrogant to learn from the local "savages", not even Christians.

Good point.

Also, Razib picks up the theme.

I was reading back through Bednarik's "Concept-mediated marking in the Lower Palaeolithic," for some background on the ochre-shellfish post, and I ran across this quote in Bednarik's rejoinder to Randall White:

[A]n estimated 100 tons of iron ore was mined at just one Middle Stone Age site, Ngwenya, carbon-dated to about 43,200 B. P. (Dart and Beaumont 1971)

That seemed striking -- that is, I hadn't seen any other references to that site -- so I tracked down a bit more information about Ngwenya. The LSA/MSA hematite quarry was described in short publications by Raymond Dart and Peter Beaumont (1967, 1969, 1971). In recent years, the quarry had been mined by a modern operation, and had been a locus of iron ore mining since LSA times at least. Dart had some interest in the idea of Stone Age mining for iron ore, having found an LSA mine in Zambia many years before. Some old flaked tools and other artifacts were found at Ngwenya, and Dart got some some archaeologists, including Adrian Boshier, to investigate.

The Swaziland National Trust has an informative, although unreferenced, website discussing the findings:

Boshier found three ancient mines named Lion, Castle and Stag caverns. He collected stone tools in and around them made of dolerite, which is foreign to the area. The tools were unlike those normally found on a stone age site, they were more specialised, consisting of choppers, picks and hammer stones. Professor Dart identified them as mining tools. The tools were not confined to the surface layers but were scattered throughout huge depressions which would have been solid haematite. In one of the mines they were lying among and beneath thousands of tons of red iron oxide known as haematite. Enquiries by Boshier among the Swazis elicited the information that haematite deposits had been mined in historic times and that it was the custom to fill in the excavation to avoid offending the spirits of the underworld. Boshier theorised that if the holes had been refilled with haematite then the mine workers must have wanted something other than haematite.

The suspicion, mentioned by Dart and Beaumont (1967), was that specularite (a dark-colored sparkly hematite) was the real objective of the quarrying -- they were also led to this idea by the fact that Castle Cavern had surface exposures of hematite, so it would hardly be worth mining deep into Lion Cavern to get it.

Anyway, once the initial excavations found a substantial antiquity for quarrying at the site, they went deeper to see how old the activity really was:

From six to eight feet, there were undoubted Middle Stone Age artefacts together with some possible Later Stone Age tools. From eight feet to worked bedrock at over eleven feet, the deposit yielded some 23,000 artefacts which belong unquestionably to a middle stage of the Middle Stone Age. Occasional stone mining tools were also found. Well-defined ash levels indicated that the assemblage was in situ. Quartz, white quartzites, grey-and-white dappled quartzite, black indurated shales, and greenish cherts were the main materials used. Most of these rock-types occur on a ridge overlooked by and about a quarter of a mile from the cavern. Some of the exposures there bear clear evidence of having been flaked. The dappled grey-and-white quartzites come from exposures about a mile and more northwest of the site (Dart and Beaumont 1969:127).

The extent of the Middle Stone Age activity at the site suggested that a vast amount of hematite had been removed:

At least 50 tons of haematite rich in specularite must have been removed from Lion Cavern; two-thirds of it during the Middle Stone Age (Dart and Beaumont 1967:408).

Their dating of charcoal nodules (Dart and Beaumont 1967) in the "middle to lower levels of the Middle Stone Age level" were 22,280 +/- 400 BP and 28,130 +- 260 BP. This was later revised (Dart and Beaumont 1971) to a larger number, based on further survey. Likewise, Dart and Beaumont (1971) provided an earlier date at or above the limits of radiocarbon, 43,200 BP.

None of this informs us about the earliest use of red pigments, which is far older, or the earliest evidence of quarrying, which is also far older. It's probably even irrelevant to the development of the MSA in southern Africa, which, again, is far older.

But in the context of the recent literature, highly focused on the "first" evidence of ochre use, or ocher engraving, or "symbolic behavior," a site like this one can get lost in the noise. Systematic utilization of one site for one purpose is not recent in the archaeological record, but when we find evidence of such places, they can be the most informative about the activities of people in the past, their transfer of information with each other, and their acquisition of resources across relatively long distances.

References:

Bednarik RG. 1995. Concept-mediated marking in the Lower Paleolithic. Curr Anthropol 36:605-634.

Dart RA, Beaumont P. 1969. Evidence of iron ore mining in Southern Africa in the Middle Stone Age. Curr Anthropol 10:127-128.

Dart RA, Beaumont P. 1971. On a further radiocarbon date for ancient mining in southern Africa. S Afr J Sci 67:10-11.

Writer Rachel D'Oro of the Associated Press reports on the repatriation of human remains from On Your Knees Cave, Prince of Wales Island, Alaska:

ANCHORAGE, Alaska - Human remains estimated to be more than 10,000 years old will be returned to southeast Alaska Tlingit tribes 11 years after they were found in a cave in the Tongass National Forest.

It's the first time a federal agency has conveyed custody of such ancient remains to indigenous groups under the Native American Graves Protection and Repatriation Act, U.S. Forest Service officials said Friday.

...

Vertebrae, ribs, teeth, a mandible and a pelvic bone were among the remains discovered in 1996 during a Forest Service archaeological survey for a proposed timber sale on northern Prince of Wales Island. The area is the aboriginal homeland for Tlingit tribes.

Prince of Wales Island is in the Alaska Panhandle, near the British Columbia border.

Some archaeologists, noting the island's placement on the coastal fringe of Beringia, have suggested that it may document some descendants of the earliest settlers of lower North and South America. In this model, people were able to bypass the Cordilleran ice sheet by skirting southward along the coast of the Pacific Northwest. The first Americans lived significantly earlier than this site, which dates at the earliest to around 10,300 radiocarbon years. But the location makes the remains possibly the best skeletal representation of the original inhabitants of the Americas.

Rex Dalton described the site briefly in a Nature news article from 2003:

In the north of Prince of Wales Island, he ventured into the 'On Your Knees' Cave -- so named because it can only be entered by crawling through a narrow tunnel -- which turned out to contain a host of specimens. Subsequent years of summer digs by Heaton and his archaeologist colleagues have unearthed the oldest signs of human habitation in the Pacific Coast region, from sediments in the cave's floor.

The specimens include a bone tool that has been radiocarbon dated to 10,300 years ago, a human bone dated at 9,200 years old, and blades made from obsidian -- a volcanic glass found in lava beds -- of the same vintage. The latter have shown the ancient inhabitants of Prince William Island to be relatively well-travelled coastal seafarers. Craig Lee, an anthropology doctoral student now at INSTAAR, has used X-ray fluorescence spectroscopy to examine trace elements in the obsidian, and so determine its source. His studies show that the material in On Your Knees Cave came from Suemez Island, about 150 km to the south, and Mount Edziza, nearly 400 km to the northwest in mainland British Columbia.

Long-distance contacts along the coast, and between coastal and inland locations, among the early descendants of the New World invaders show the potential for rapid movement down the western coast of the Americas.

That archaeology expresses how important the site is for understanding early New World populations. But what about the skeleton -- how have the human remains contributed to our knowledge?

These remains are relatively fragmentary and therefore don't provide a lot of anatomical information that could be compared to recent people. But they contain a wealth of genetic information, of the kind that has been retrieved more and more routinely during the last 10 years.

Kemp and colleagues (2007) examined the DNA from the human remains, successfully extracting both mtDNA and Y chromosome markers that permitted analysis of the specimen's place relative to New World diversity. The conclusions help to emphasize the importance of such early skeletal remains:

Mitochondrial and Y-chromosome DNA were analyzed from 10,300-year-old human remains excavated from On Your Knees Cave on Prince of Wales Island, Alaska (Site 49-PET-408). This individual's mitochondrial DNA (mtDNA) represents the founder haplotype of an additional subhaplogroup of haplogroup D that was brought to the Americas, demonstrating that widely held assumptions about the genetic composition of the earliest Americans are incorrect. The amount of diversity that has accumulated in the subhaplogroup over the past 10,300 years suggests that previous calibrations of the mtDNA clock may have underestimated the rate of molecular evolution. If substantiated, the dates of events based on these previous estimates are too old, which may explain the discordance between inferences based on genetic and archaeological evidence regarding the timing of the settlement of the Americas. In addition, this individual's Y-chromosome belongs to haplogroup Q-M3*, placing a minimum date of 10,300 years ago for the emergence of this haplogroup.

Possibly the most significant aspect of ancient specimens is their ability to inform directly about the rate of sequence changes over time. Phylogenetic rates of change in mtDNA (e.g., between humans and chimpanzees) appear to have been relatively slow compared to the observed number of mutations between parents and offspring. There are two reasons for this: Some mutations are lost because of purifying selection, and some recur again and again at the same site, and therefore saturate over long time scales. But it is difficult to estimate the relative importance of these factors, and therefore it is hard to assign rates across different time scales (e.g., the founding of New World populations, modern human origins, etc.). Kemp et al. (2007) used the ancient mtDNA sequence from On Your Knees Cave to arrive at an estimate of the rate of change across the 10,000-year span, which ought to allow a more precise chronology for the New World founding:

Applying our most conservative rate of 34%/site per myr (95% CI 15-53%/site per myr) to the nucleotide diversity estimate (pi = 0.86) for mtDNA haplogroups A, B, C, and D in Native Americas (Bonatto and Salzano, 1997b), indicates that human entered the Americas ca. 13,438 YBP (95% CI 8,113-28,667
YBP). While this estimate does not preclude the possibility of an early entry, the estimate is also compatible with an entry more recent than 15,000 YBP (Kemp et al. 2007:617).

That is in contrast to some earlier genetic estimates, which had suggested founding times as early as 40,000 years ago -- often suggested as compatible with a very long-term occupation of Beringia.

Soon, we will surely see more testing of early specimens to try to assess the genotypes for other loci. For example, the idea of an early population bottleneck during the founding of New World populations has become an important hypothesis for explaining the limited variation of many genes in the Americas. But later events may also have been important in limiting variation. For example, Native American populations have substantially less allelic variation at HLA loci than do Asian populations. This reduction in diversity probably began with the initial founding and subsequent dispersal, but may also have involved natural selection during the last 10,000 years. The importance of the initial bottleneck may be tested by finding HLA types for early American skeletons -- if the founding event was almost solely responsible for the current HLA diversity, then the early skeletal samples should be comparable in diversity to recent samples. If they show much more diversity (for example, HLA haplotypes absent in recent Americans) then we can conclude that selection in later populations played more of a role -- implying a different scenario for pathogen-host evolution over time in the Americas.

In that light, repatriating a 10,000-year-old skeleton must subtract from our future inquiries into the origins of New World peoples. Or I should say, patriating, since it isn't being sent back to its people, it is being given to entirely new people who have no demonstrated relationship to the skeleton at all.

I do perceive the real benefits from cordial and cooperative relationships with indigenous peoples, particularly where tribes have well-defined and recognized historic territories. The vast majority of skeletal remains of ancient Americans are quite recent, and might in most cases (given sufficient evidence and analysis) be attributable to particular historic cultural groups.

But for remains over a few thousand years old -- and certainly for the earliest New World populations -- every living person of Native American descent may count these early skeletons among their ancestors.

References:

Dalton R. 2003. Archaeology: The coast road. Nature 422:10-12. doi:10.1038/422010a

Kemp BM and 13 others. 2007. Genetic analysis of early holocene skeletal remains from Alaska and its implications for the settlement of the Americas. Am J Phys Anthropol 132:605-621. doi:10.1002/ajpa.20543

Science's Michael Balter reviews the recent Cambridge conference on "Global Origins and Development of Seafaring". The article begins with a suggestion that the first inhabitants of Flores floated there on vegetation rafts by accident -- channel crossings being otherwise impossible for Lower Paleolithic hominids:

"Flores is the exception that proves the rule in terms of when seafaring really began," says Atholl Anderson, a prehistorian at the Australian National University (ANU) in Canberra. [Jon] Erlandson agrees: "Otherwise, H. erectus should have colonized Australia and the surrounding islands."

It mostly seems to be about Wallacea, Sahul, and Melanesia.

The article features a disagreement concerning the colonization of these regions. Some think that island colonizations started before seafaring technology was quite ready for prime time. In that scenario, the initial habitation of parts of Wallacea along with Australia and New Guinea was a sort of accidental chain of small founding events, possibly as early as 60,000 years ago or earlier.

The opposing viewpoint holds that these islands (and continent) were inhabited relatively late and quite suddenly, by people who had developed an advanced seafaring skill. Balter quotes University of Utah archaeologist Jim O'Connell to good effect:

In the last few years, O'Connell, together with archaeologist Jim Allen of La Trobe University in Bundoora, Australia, has argued from a detailed analysis of radiocarbon dates for a "short chronology" that puts the occupation of Sahul no earlier than about 50,000 years ago. He pointed out that by 45,000 years ago modern humans had colonized a number of islands between Sunda and Sahul, called the Wallacean Archipelago, which stretched at least 1000 kilometers even when sea levels were at their lowest. Reaching many of these islands required sea crossings of 30 to 70 kilometers, sometimes against the currents. Most animals from Asia never achieved these crossings, implying that humans must have used technology to do it. That 5000 years of colonization, O'Connell said, represented a relatively short "archaeological instant."

O'Connell also argues that some of the island sites before 40,000 years ago include deep-water fish, suggesting relatively advanced ocean-going boats at that time -- something I noted in a post on the East Timor site, Jerimalai.

Which side is right? I don't know, but it's good that they are formulating hypotheses this way, involving the technological trajectory, genetic constraints on small populations, and various ecological parameters.

References:

Balter M. 2007. In search of the world's most ancient mariners. Science 318:388-389. doi:10.1126/science.318.5849.388

Slimak and Giraud report Comptes Rendus Palevol that a small proportion (<1%) of artifacts from the Mousterian of Champ Grand, in central France, come from distances over 250 km away. That long-distance transport is rare at the site, but is even more rarely observed in assessments of Mousterian assemblages.

Out of 10 artifacts with distant sources, six are from far to the north of the site (in the Loire Valley and Paris Basin) while two are from equivalent distances to the south. The site itself is in the Rhône drainage, leading the authors to conclude that the long-distance transport demonstrates interaction of peoples between at least the Loire and Rhône valleys.

Julien Riel-Salvatore notes that the conclusion of the full paper (in French) compares the Mousterian with nearby Magdalenian and Gravettian raw material origins. In the Upper Paleolithic instances, the maximum distances are not larger but the ratio of exotic materials is vastly higher, with local flints making up only a small proportion of the artifact count. He translates a snippet; I'll translate the sentence that stood out most to me:

The ratios of the primary materials seem to clearly differentiate Upper from Middle Paleolithic groups. On the other hand, though the material ratio is distinct, the territorial circuits are revealed to have a certain similarity among these occupations across time. The temporal persistence of circuits for long-distance provisioning give rise to an idea of territorial bonds connecting Paleolithic societies over time. Particularities are therefore to be found in the technical behaviors of these societies and in the details of their tool industries, and not in any differences in territorial organization. Likewise, the secondary networks spanning toward the Mediterranean document the movement of stone over geographic spaces as vast as those now recognized during the Upper Paleolithic, and underline clearly our poor knowledge of the societies of the Middle Paleolithic.

(via Julien Riel-Salvatore)

References:

Slimak L, Giraud Y. 2007. Circulations sur plusieurs centaines de kilomètres durant le Paléolithique moyen. Contribution à la connaissance des sociétés néandertaliennes. Comptes Rendus Palevol (in press) doi:10.1016/j.crpv.2007.06.001

It is no secret that I really don't like the hypothesis that the massive ancient eruption of Mt. Toba, Sumatra, wiped out much of the worldwide human population 74,000 years ago, possibly allowing modern humans to spread in its wake.

Sure, this eruption was the largest known within the last half-million years. If any ancient volcanic event was going to have an effect on human populations and world climate, it would be this one. And it remains quite possible that there were severe climatic effects lasting a millennium or more.

But there has never been any sign of anatomical or archaeological discontinuity outside Africa at this time. Moreover, no genetic evidence suggests a sudden harsh bottleneck at 74,000 years ago -- most genes are consistent with such a bottleneck only because a recent, sudden, and short bottleneck would have almost no effect on gene diversity. Considering that the Neanderthals in glacial Europe continued right on after the Toba eruption without any hiccup, it always seemed like a very shaky idea.

But still, there seemed to be nothing impossible about a more local effect of the eruption. I mean, if a giant megavolcano spouts off right next door, it has to be bad, right?

Well, maybe on Sumatra itself, but apparently not in some other fairly nearby places. This week's paper by Petraglia and colleagues (2007) appears to have sunk the Toba bottleneck entirely. Very simply, they found a Toba ash horizon in India, and found very similar archaeology both below and above the eruption.

Based on some features of the tools, Petraglia and colleagues speculate that the makers may have been a relatively early sample of modern humans:

Analyses of the archaeological industries recovered from the site indicate a strong element of technological continuity between the pre- and post-Toba assemblages. Together with the presence of faceted unidirectional and bidirectional bladelike core technology, these pre- and post-Toba industries suggest closer affinities to African Middle Stone Age traditions (such as Howieson's Poort) than to contemporaneous Eurasian Middle Paleolithic ones that are typically based on discoidal and Levallois techniques (Fig. 3). The coincidence of (i) evidence of hominins flexible enough to exhibit continuity through a major eruptive event, (ii) technology more similar to the Middle Stone Age than the Middle Paleolithic, and (iii) overlap of the Jwalapuram artifact ages with the earlier end of the most commonly cited genetic coalescence dates (21-23) may suggest the presence of modern humans in India at the time of the YTT event. This interpretation would be consistent with a southern route of dispersal of modern humans from the Horn of Africa (24); the latter, however, will remain speculative until other Middle Paleolithic sites in the Indian subcontinent and Arabian Peninsula (25) are excavated and dated.

I tend to discount point (i) about flexibility, since European Neandertals were apparently flexible enough to survive ice ages with large decade-scale swings from warm to cold. But it is hard to get people to Australia by 50,000 years ago unless they were in India before that.

A dispersal of MSA people from Africa would be an interesting twist on the "modern human origins" problem. If the first "modern" humans outside Africa were MSA users, there is no particular reason to assert that they were different from the population represented at Skhul and Qafzeh. The lack of a full Upper Paleolithic technical kit anywhere in Africa before 50,000 years ago makes an MSA-associated disperal seem more credible. The assembly of the Upper Paleolithic in Eurasia would therefore be a local cultural development, possibly associated with further biological change.

I find that association to be the most important reason to continue investigating these sites. In the meantime, we can forget about the cataclysmic effect of Toba on the poor hominids.

References:

Petraglia M, Korisettar R, Boivin N, Clarkson C, Ditchfield P, Jones S, Koshy J, Lahr MM, Oppenheimer C, Pyle D, Roberts R, Schwenninger J-L, Arnold L, White K. 2007. Middle Paleolithic assemblages from the Indian subcontinent before and after the Toba super-eruption. Science 317:114-116. doi:10.1126/science.1141564

Der Spiegel reports on recent portable art finds at Vogelherd, Germany:

The figure of the woolly mammoth is tiny, measuring just 3.7 cm long and weighing a mere 7.5 grams, and displays skilfully detailed carvings. It is unique in its slim form, pointed tail, powerful legs and dynamically arched trunk. It is decorated with six short incisions, and the soles of the pachyderm's feet show a crosshatch pattern. The miniature lion is 5.6 cm long, has a extended torso and outstretched neck. It is decorated with approximately 30 finely incised crosses on its spine.

Nick Conard at Tübingen is quoted; he's the responsible archaeologist. The story is on occasion of the mammoth and other artifacts going on display at a museum exhibit. They are dated Aurignacian, which makes them among the earliest examples of figurative art in Europe.

It's likely that these include the figurines that Conard was presenting in 2003, as reported by Rex Dalton, although a mammoth was not mentioned at the time. A series of portable art figures were discovered at Vogelherd by Gustav Riek, who excavated the cave in 1931. Several of these are housed at the Museum Schloss Hohentübingen, including another mammoth. Conard (2003), in his description of portable art from Hohle Fels, includes a table listing 10 figurines from Vogelherd, all found in the original excavation by Riek.

Conard and colleagues (2003) reported on the radiocarbon chronology of the Aurignacian at Vogelherd, finding a range of AMS dates between around 29,000 and 36,000 radiocarbon years, with most dates clustering between 30,000 and 31,000. Figurines from other caves in the region date to the same age range, including those from Hohle Fels, Geissenklüsterle, and the Löwenmensch, or "Lion-man" from Hohlenstein-Stadel. This area preserves an exceptional sample of early Aurignacian art objects.

References:

Conard NJ. 2003. Palaeolithic ivory sculptures from southwestern Germany and the origins of figurative art. Nature 426:830-832. doi:10.1038/nature02186

I happened across an interesting article from last year by Christina Giovas that looks at pigs in Polynesia. People carried pigs with them to most of the islands that they colonized, excepting some distant and relatively recent places such as Rapa Nui (Easter Island) and New Zealand. These places presumably didn't get pigs, either because sufficient numbers did not survive the initial ocean voyage, because of low rates of subsequent contacts that might have brought pigs, or because the necessary forage for pigs was not present in sufficient quantity to establish them -- especially since pigs and people compete for many of the same foods.

But some islands that didn't have pigs at the time of European contact nevertheless have ancient archaeological evidence of pigs. So people brought pigs to those islands and established them, but they subsequently died out.

Here are the key paragraphs form Giovas' introduction:

Nonetheless, archaeological data in combination with the accounts of early European explorers reveal a pattern of pig distribution far more extensive in prehistory than at the time of historic contact (Fig. 1) (Alien et al. 2001; BayPetersen 1983; Bellwood 1987; Dye and Steadman 1990; Kirch 1991, 200Ob; Kirch and Yen 1982; Rolett 1998), suggesting that prehistoric Polynesians either allowed swine herds to die out or intentionally exterminated them. Whichever of these is the case, it appears that pig extirpation in Polynesia constitutes one of the few known instances of domestic species extinction (Ramis and Bover 2001), making it highly significant to the history of human-domesticate interactions.

It has been suggested that animal husbandry was simply less feasible on resource-impoverished islands (Anderson 2001, 2002; Bay-Petersen 1983; Kirch 2000b), particularly since husbandry practices involved feeding pigs cultivated crops, setting up an element of resource competition between pigs and their Polynesian keepers. Underlying this explanation are assumptions about island ecology and its impact on pigs and humans alike. Although the relationship is seldom made explicit, these ecological factors are presumed to operate according to principles of island biogeography, particularly the relationship of island area to species extinction. Other factors may also influence the likelihood of extinction, including island geology, elevation, and latitude and longitude. Here I test the relationship between pig extirpation and these variables. I propose that the pattern of prehistoric distribution for domestic pigs in Polynesia may be best understood in island biogeographic terms and that resource competition may represent the overarching causal mechanism driving pig extirpation, as Kirch (2000b) has argued. To begin, I offer a brief overview of the role of pigs in Polynesian society, followed by a discussion of the relevant principles of island biogeographic theory and the mechanisms-both environmental and cultural-that may have brought about pig extirpation in Polynesia (Giovas 2006:69-70).

Obviously, on the islands where pigs were extirpated, humans were a factor in killing them. But there is this question: did extirpation sometimes result from a deliberate plan, where people recognized that the pigs were eating vegetable foods the people needed themselves? Or did they just eat all the pigs, possibly during a shortfall, and not restock them from other islands.

In times of resource shortfall, pigs would have been effectively competing with people for the same agricultural produce, placing Polynesians in a position in which the benefits of pig husbandry may have been outweighed by its relatively high economic (energetic) cost. As Kirch and others have suggested (Alien et al. 2001; Bay-Petersen 1983; Kirch 2000b), trophic competition on this level may explain why animal husbandry failed in many parts of Polynesia. Those islands prone to resource shortfalls would have been at a greater risk for failure of pig husbandry simply because crop harvests may have been insufficient to support both humans and pigs. The onset of this effect need not have been sudden or severe. Instead, it may have operated slowly but systematically over decades or more (Giovas 2006:72).

Since many of the islands were in periodic contact with other societies, pigs might have redispersed in a number of cases, and possibly pigs were maintained over long times on some islands that otherwise would have lost them by recurrent contact. Giovas approached this issue of "social isolation" in an interesting way:

On the other hand, where human interaction between islands was frequent, it may have supplied a type of rescue effect (Brown and Kodric-Brown 1977) in which the continual immigration of domesticates safeguarded against their disappearance from an island. In this scenario, isolation comprises not only a geographic but also a social component in which substantial geographic isolation may be overcome in part by cultural forces. Weisler (1994, 1995, 1996, 1997; Woodhead and Weisler 1997), for example, has documented the existence of a long-distance economic interaction sphere among the remote islands of Mangareva and the Pitcairn group. The subsequent decline of settlements on Pitcairn and Henderson may have come about in part because of the breakdown of interisland voyaging between these islands (Giovas 2006:75, emphasis in original).

This concept of social isolation serving as a substitute for geographic isolation is very interesting to me; it adds a historically fluctuating component to the usual isolation factor treated by biogeographers.

Giovas found that island area was a strong predictor of whether pigs were extirpated, with most of the cases of pig loss being relatively small islands. That is in line with the prediction of island biogeography, at least in terms of the ability of larger islands to support more species within a given ecological space.

Island elevation was also related; extirpation was more likely on very level atolls. But it wasn't clear that this correlation remained true after controlling for island area; the two have a strong relationship. Still, a higher island might be one where humans have more trouble using all resources, as some remain at altitudes or on slopes used only occasionally by people. In other words, a higher island has more potential "wilderness" space where feral pigs might escape and avoid capture.

I find myself wondering whether an additional historical component may be important. Pig populations have the potential of growing quite a bit faster htan human populations, especially when human consumption of them is relatively low and natural forage is available. In other words, during the early years after a colonization, pigs may have grown faster than people.

But later in time, the people caught up in many islands; putting more and more pressure on the ecological space available to both people and pigs. In these contexts, the pigs would have lost out. So demographic growth and competition between humans and pigs predicts a pattern in which many islands start with pigs, but then lose them as human populations catch up and overtake them in size.

We might predict on this demographic basis that pigs would have died out on other, larger islands if Polynesian history had continued without interruption from European explorers. No island was likely to have been a steady-state with equilibrium in pig and human population sizes, although the joining of nearby islands into interacting culture groups might have moderated the effect.

References:

Giovas CM. 2006. No pig atoll: island biogeography and the extirpation of a Polynesian domesticate. Asian Perspectives 45:69-95.

Bouzouggar et al. (2007) report on a series of perforated Nassarius shell beads found in a layer dating to ca. 82,000 years ago in Grotte des Pigeons, Morocco.

The shells are similar to the ones that Marian Vanhaeren found in a drawer of the British Museum last year, from Skhul. Those shells are believed to date to the time of the Skhul fossil series, over 100,000 years ago. At present, they're basically the only evidence of any behavioral difference between the early modern humans from Skhul and Qafzeh and either earlier or later Neanderthal-like people from Tabun, Amud, or Kebara. It's not much, but it's a little.

In last year's paper, Vanharen et al. (2006) also reported a single perforated Nassarius shell from Oued Djebbana, Algeria. The date was unknown, believed by radiocarbon to be older than 35,000 years. That followed after the discovery of 41 Nassarius shell beads from Blombos, South Africa (Henshilwood et al. 2004). Although there were doubts with those finds (expressed in news stories by Michael Balter and Constance Holden), the Blombos finds are quite compelling:

Small objects may easily be displaced through archaeological layers, and perforated tick shells were also recovered at Blombos Cave from the more recent LSA layers. OSL measurements on 1892 individual quartz grains from the aeolian sand layer that separates the LSA and MSA levels (6) indicates no contamination by grains of different ages, contraindicating downward percolation of younger objects. Also, MSA beads are significantly larger (P < 0.0001) than those from LSA levels; the most common MSA perforation type is present on <1% of the LSA shells; LSA beads do not have the wear facets found on MSA specimens; and only 5% of MSA beads have broken lips, compared to 52% of LSA beads, suggesting that the latter were strung in a different way. MSA beads are dark orange or black, whereas those from the LSA are white or pale beige (fig. S1). MSA shells were found in clusters of 2 to 17 beads, with each group clustering in the same or neighboring 50-by-50-cm quadrates. Within a group, shells display a similar size, shade, use-wear pattern, and perforation size. Each cluster may represent beads coming from the same beadwork item, lost or disposed during a single event (Henshilwood et al. 2004:404).

There is perhaps a question as to whether the holes might represent eating the gastropods inside the shells rather than stringing them, but the Blombos beads appear to have been colored by red ochre or put in contact with other objects that were.

The collection from Grotte des Pigeons is not quite as numerous as the Blombos sample (with only 13 shells recovered), but like Blombos, they are in situ and with fairly clear associations. Also, Bouzouggar et al. can give pretty good detail about why humans had to bring them and how they were made:

The N. gibbosulus shells certainly were brought to the site by humans. The local dolomitic bedrock is too old to be a source, predating the origin of the species (36). The distance from the site to the contemporary coast could not have been <40 km (37), too far for natural processes known to carry marine shells inland, such as animal predators or major stor ms (38). It also is clear that the N. gibbosulus were not intended for human consumption because all show features characteristic of dead shells accumulated on a shore. These features include encrustations produced by bryozoa, tiny shells, and sea-worn gravel embedded into the body whorl and perforations produced by a predator on the ventral side of the shell (SI Fig. 7). Comparison with the perforation pattern recorded on a modern thanatocoenosis of this species reveals that the Taforalt [i.e., Grotte des Pigeons] shells do not represent a random selection from a natural assemblage of dead shells (Fig. 5). None of the archaeological examples is undamaged, whereas almost half of those from the comparative sample are intact, and the perforation type most common on the archaeological specimens is rare in nature. This type, a single perforation on the dorsal side at the center of the last spiral whorl, is observed in only 3.5% of the comparative sample; the probability of randomly collecting a sample of shells like that from Taforalt is extremely low (P 0.0001), which suggests that the shells with a perforation on the dorsal side were either deliberately collected or perforated by humans. Although the latter seems more probable, the agent responsible for the perforations cannot be firmly identified. Microscopic features diagnostic of human intervention in the production of the perforation are absent (39). Hole edges on the dorsal aspect are rounded and smoothed on four shells. The remainder have irregular outlines with chipping of the inner layer, indicating the agent responsible for the perforation punched the shells from the outer dorsal side. Holes with irregular edges may be obtained by punching the dorsal side with a lithic point (2, 11). Smoothed hole edges have been replicated by wearing str ung modern shells (39). Both types of hole edges occur on shells used as beads in Upper Paleolithic sites (40)....

Possible evidence for the stringing of the perforated shells as beads comes from the identification on ten specimens of a wear pattern different from that observed on both the modern reference collection and unperforated specimens from Taforalt. The wear in the latter case homogeneously affects the whole surface of the shells and consists of a microscopic dull smoothing associated with micropits and rare short, randomly oriented striations. The wear on the presumed strung examples is found on the perforation edge and on spots of the ventral and lateral side, and it is characterized by an intense shine associated with numerous random or consistently oriented striations (Bouzouggar et al. 2007:9966-9967).

Like the Blombos shells, a number of those from Grottes des Pigeons preserve "residue" of pigment on their surfaces:

The most likely explanation for the presence of pigment on the shells is their rubbing against material embedded with ocher, such as hide, skin, thread, or other substance. We can rule out accidental causes because in two specimens colorant is stuck in microcracks that cross the worn area, indicating that wear and coloring werre intertwined processes. No other objects (e.g., artifacts or bones) from these deposits carry similar pigments, nor are there obvious particles of natural ochres/ores in the sediments (Bouzouggar et al. 2007:9968).

So here, the critical evidence is that (a) the shells were dead when collected; (b) they were transported by people over 40 km from the shore to the cave; (c) they were worn by stringing; and (d) they were colored with pigment, directly or by contact with something also worn and pigmented.

I don't know that you can do much better than this, unless you find them draped across the neck vertebrae of a skeleton.

What is notable about this? I would say, more important than the date (with now three sites clearly over 70,000 years) is the geographic extent of the perforated shells. Africa is a big continent, and now there are shell beads from the three furthest corners of it (Israel being just above the northeast corner). This suggests a very widespread diffusion or dispersal of shell bead-making; yet the Middle Stone Age was a time of increasing regional distinctiveness of technological industries within Africa. If North, South, and East Africa had different traditions, why did they share beads made from these particular shells -- and in two instances, at least, colored red?

References:

Balter M. 2006. First Jewelry? Old shell beads suggest early use of symbols. Science 312:1731. doi:10.1126/science.312.5781.1731

Bouzouggar A and 14 others. 2007. 82,000-year-old shell beads from North Africa and implications for the origins of modern human behavior. Proc Nat Acad Sci USA 104:9964-9969. doi:10.1073/pnas.0703877104

Henshilwood C, d'Errico F, Vanhaeren M, van Niekirk K, Jacobs Z. 2004. Middle Stone Age shell beads from South Africa. Science 304:404. doi:10.1126/science.1095905

Holden C. 2004. Oldest beads suggest early symbolic behavior. Science 304:369. doi:10.1126/science.304.5669.369

Vanhaeren M, d'Errico F, Stringer C, James SL, Todd JA, Mienis HK. 2006. Middle Paleolithic shell beads in Israel and Algeria. Science 312:1785-1788. doi:10.1126/science.1128139

Chickens were brought to South America in Precolumbian times by Polynesians.

It's all over the wires, so I'll just point to John Noble Wilford:

That is the conclusion of an international research team, which reported yesterday that it had found "the first unequivocal evidence for a pre-European introduction of chickens to South America," or presumably anywhere in the New World.

The researchers said that bones buried on the South American coast were from chickens that lived between 1304 and 1424. Pottery at the site was from a similar or earlier time. A DNA analysis linked the bones, which were excavated at El Arenal on the Arauco Peninsula in south central Chile, to chickens from Polynesian islands.

About half the news articles seem to be leading with, "Why did the chicken cross the Pacific Ocean?" This one is no exception. Har, har, groan.

I don't really have much to say about it, it seems like a very straightforward discovery. There is a radiocarbon date and the DNA evidence. Also, the early postcontact historical record corroborates:

Others thought [chicken arrival with the Spanish] unlikely, noting that when the Spanish invaded Peru in 1532, they saw chickens being used in traditional ceremonies. It seemed hard to believe, some scholars pointed out, that chickens would have been so rapidly dispersed from the east coast to the west and already be incorporated in religious events.

Charles Mann's book 1491 doesn't review this example, but it does talk about analogous kinds of early post-contact documentary evidence from New World peoples. It seems to be an increasingly important source of information to corroborate archaeological findings.

And the chicken transfer does help to explain the sweet potato problem:

The presence of the South American sweet potato in pre-European sites in Polynesia indicated some prehistoric contact between America and the islands.

I've never understood why this has been so quickly waved away. I mean, just last month this Nature News article reviewed a study that claimed that sweet potato seeds could have traveled to Polynesia on a free-floating unmanned ship.

Good grief. I suppose the chickens manned the boat. Er, chickened the boat?

Foods like these have to be among the fastest things to diffuse, even given relatively rare population contacts -- and certainly the Postcolumbian exchange between New and Old Worlds demonstrates this. I suppose the most negative evidence is the lack of evidence for other South American crops, like maize. Maybe the sea travelers used it all to feed the rats?

I mean, rats made it as far as Easter Island, why not the next step? Maybe some South American rats are actually Precolumbian also?

The only thing faster is disease -- and fortunately for the Americas, eastern Polynesia didn't have many of those to transfer.

Wilford's article ends with this:

Scholars found it disappointing and puzzling that the Polynesians who landed at El Arenal left nothing more than chicken bones. Pottery at the site is in a local style. Perhaps the visitors ate and ran, but not without leaving behind some starter chickens for future plates of arroz con pollo.

This seems quite obvious: the chickens were introduced a lot earlier than 1304. They would perhaps have been the longest-lasting element of the cultural transfer -- they wouldn't even have necessarily required permanent settlements, although a more substantial presence might well have occurred. Chickens are the most sensitive sign we can expect to see, just as sweet potatoes are the most sensitive sign on the other side of the contact. You aren't going to find the one place where Polynesians showed up -- you are going to find some site 500 years later when the chickens have spread across half the continent.

James Adovasio, Olga Soffer and Jake Page have a new book entitled, The Invisible Sex: Uncovering the True Roles of Women in Prehistory. The authors are well-known for their work in both New World and Old World archaeology. In particular, the joint work by Adovasio and Soffer has uncovered evidence for the earliest fabrics and fiber technology, and has led to new interpretations for the famous "Venus" figurines from the European Upper Paleolithic.

I ran across a nice long review of the book by Laura Miller at Salon.com. It's free if you watch their ads, and the review is full of clever observations. Here's a sample:

Their point is that, like Hollywood action films, many early conceptions of prehistoric life were fantasies, the work of anthropologists caught up in a thrillingly macho vision of our forebears that owes more to Conan the Barbarian than to the archaeological record. That vision rarely featured women, and when they did appear it was only to sit around awaiting the next delivery of mammoth steaks, for which, it was implied, they would trade their sexual favors or perhaps the handful of nuts and berries they'd rustled up on the side. So seductive is this "theme of man the hunter" that it prevailed when the remains of a diminutive new species of the genus Homo were discovered on the Indonesian island of Flores in 2004 (and promptly labeled "hobbits" by the press). An artist's drawing of the creature depicted it as bearded fellow holding a spear and carrying a freshly slain giant rat slung over his shoulder -- despite the fact that the chief find was a female.

The review notes that the book also covers the anatomical constraints of the birth process in humans and their implications for cultural assistance with birth -- that's drawn from work by Karen Rosenberg and Wenda Trevathan (quick summary here) -- and I happened to have lectured about it today. It's very important stuff in terms of human life history strategies, and it is likely tied in with the evolution of the human brain. So anatomically speaking, women are central!

I hope to write more about this book when I get a chance to read it -- Soffer and Adovasio have been really important in reframing our understanding of sex roles in the past, and this looks like an interesting contribution.

The New Yorker has a nice profile of origami artist (and physicist) Robert J. Lang. My print edition of Discover had a profile of Lang earlier this year, which has become an online feature complete with illustrations.

The New Yorker story sort of leads with a dog-bites-man "well-groomed artist" story. People tend to forget that the original "Renaissance men" were skilled practical chemists (pigments) and physicists (optics) as well as painters and sculptors. There is always a long series of steps involved in the creation of art, steps that require collecting special resources, creating and manipulating technology, and bringing observations into a conceptual framework.

For this last step -- the conceptualization -- origami has lately become the province of mathematics:

He would have liked to have folded insects, but, in those years, bugs, as well as crustaceans, were still an origami impossibility. This was because no one had yet solved the problem of how to fold paper into figures with fat bodies and skinny appendages, so that most origami figures, even television characters and heads of state, still had the same basic shape as the paper cranes of nineteenth-century Japan. Then a few people around the globe had the idea that paper folding, besides being a pleasant diversion, might also have properties that could be analyzed and codified. Some started to study paper folding mathematically; others, including Lang, began devising mathematical tools to help with designing, all of which enabled the development of increasingly complex folding techniques. In 1970, no one could figure out how to make a credible-looking origami spider, but soon folders could make not just spiders but spiders of any species, with any length of leg, and cicadas with wings, and sawyer beetles with horns. For centuries, origami patterns had at most thirty steps; now they could have hundreds. And as origami became more complex it also became more practical. Scientists began applying these folding techniques to anything -- medical, electrical, optical, or nanotechnical devices, and even to strands of DNA -- that had a fixed size and shape but needed to be packed tightly and in an orderly way.

This progression is illuminating. At first, thirty steps or less -- and yet, this was a hundreds-of-years-old art form. The constraints were learning (mastering the basic techniques of folding and progressively more difficult combinations of steps) and innovation (extremely high probability of failure in objects of greater than this complexity).

Additionally, we may consider that aesthetic considerations coming from Japanese culture have driven some constraints (beauty, simplicity).

These cultural constraints themselves are process-dependent. If it were very easy to have made more complicated patterns, the value of simplicity might have been less apparent; on the other hand, the existence of an aesthetic of simplicity tends to constrain artists from experimentation with more complex forms.

Here, the artists begin with a raw material (paper) that is highly standardized is shape and form (flat, usually square) and originally, all origami was made on plain white paper. This has changed so that an endless variety of colors and textures are now used, but the starting point is still a uniform flat piece of paper.

With successive steps, there are many more ways to go wrong than to go right, and these compound as the piece becomes more complicated. Even the simplest folded crane has a high element of non-obviousness about it. No one on earth could fold an insect as recently as thirty years ago.

Simplicity may be a design feature. It may equally result from limited information -- either because information transfer is limited or because the information quantity increases too rapidly for efficient

The problem has been to devise a method for finding longer pathways to more complex shapes in an exponentially increasing sea of jumbled-looking possibilities. Lang is famous in large part because he developed software to help the process. As the Discover article makes clear, the software doesn't solve all the problems, it just narrows the possibilities. Still, this provides a light at the end of the tunnel for many complex designs -- the designer can at least know that there is a way, even if it is going to take some doing to figure it out.

At the same time, information transfer between origami artists has massively intensified. The New Yorker article lays out a short history of the art form, which blossomed during the mid-20th century as paper-folding was included in elementary school curricula, and popular magicians like Harry Houdini published books on the topic. The blossoming of more and more complex origami forms during the 1990's was made possible by international organizations and competitions -- effectively providing incentives for high-stakes exploration of folding-spaces. As people spent more time on origami, they found new ways to support themselves, from publishing instructional books to consulting with NASA on ways to fold solar panels. In short, origami became a skilled trade with multilevel professional communications.

So, if we ask the question, "How did this change in technology come about?", there are at least three answers. First, origami was adopted broadly outside the culture of its origin, causing new aesthetics to be applied to its products. Second, the incentives for innovation greatly increased, causing people to spend more time exploring folding pathways with high failure rates. Third, new search strategies and communication strategies increased the acquisition and transfer rates of information between origami artists.

With these changes, a group of artists following a broad but shallow tradition made a transition to a rich and deep field of possibilities, but a field increasingly constrained by a few important pathways widely shared among them. The essential methods for creating the narrow-appendages shared by insects, animals and human forms are a key example. Once these techniques were worked out, they were shared, subjected to subsequent alterations, and transmuted into legs, antlers, and horns.

(As an aside, the fact that magicians were an important part of this transition is characteristic of the same changes occurring in the field of illusion. The vast increases in complexity of equipment and processes, and their proliferation into more and more "unique" tricks has

How can you not love this?

In fact, origami as therapy has its proponents in 1991, at the Conference on Origami in Education and Therapy, a mental-health professional presented a paper detailing her origami work with prisoners. "The most rewarding of experiences," she wrote, "was that of observing the effect that Origami had on psychopathic killers."

(via Gene Expression)

Here's a LiveScience story by Heather Whipps, about the discovery of chimpanzee nutcracking stones dating back to 4300 years ago:

Though there were no chimpanzee remains at the settlement, testing by archaeologists revealed the tool-laden camp was most likely used by the Great Ape. The stones were much bigger than anything a human could use comfortably and bore the residue of nuts that modern chimpanzees like to snack on.

"This is the only case of any prehistoric, non-human Great Ape tool use ever discovered," [archaeologist Julio] Mercader told LiveScience.

That's very cool. The news piece claims that this is great vindication for the idea that chimpanzees developed this ability without exposure to humans. That is, some people had argued that chimpanzees might have been "acculturated" to crack nuts by watching nearby people. Personally, I never thought there was much to that idea, since nutcracking is so widespread among chimpanzees and clearly learned by chimps with minimal or no human contact.

The most interesting part to me is the possibility that archaeologists will develop a search strategy for stone tools older than flaked stone tool manufacture.

John Hoffecker, one of the authors of the Science paper by Anikovich et al., wrote a consideration of some of the points in my two posts of last week (here, and here).

Hoffecker suggests that the Strelets assemblages (the ones with Middle Paleolithic elements) are unlikely to have been produced by Neandertals, both because they persist until relatively recently, and because they are found at much higher latitudes than Kostenki, for example at Mamontovaya Kurya. I have some quite contrasting e-mail from a long-time correspondent, who offers that the Strelets assemblages are quite comparable to Szeletian, generally considered to be a Neandertal-produced "transitional" industry, and there is no diagnostic skeletal evidence to suggest these tools were not Neandertal-manufactured.

Personally, I would observe that there may be no predictive reality to the Neandertal-modern distinction, certainly not within this post 45,000-year timeframe. Genetics now provides good evidence that living humans descend from an ancient structured population with a significant fraction of Eurasian members. It is of course possible that some (or even all) European Neandertals still became extinct without issue -- the genes do not have "Neandertal" stamped on them. But the fossil evidence certainly supports the hypothesis that the "Upper Paleolithic revolution" in Europe involved some (i.e., enough to be visible) population mixture.

Whatever the genetic relationships of the hominids, there was evidently no information barrier between them capable of preventing the social learning of stone reduction sequences. The "transitional" industries are sufficient to demonstrate this information transmission. To be sure, there is a limit to which we can infer contacts from archaeological assemblages, which represent industries that in some cases lasted for many thousands of years. Just as for the genes, we cannot say whether these exchanges were sporadic or regular, large-scale or small-scale.

What does that mean for Kostenki? I think it means there is no contradiction between a long-term, widespread "transitional" industry and the idea that such industries have origins in the Middle Paleolithic. Both can be true. This implies things about the population of Eastern Europe, in terms of genetics, ecology, and the dynamics of information transfer. Where industries are interleaved at a single geographical location, this may say much about both natural ecology (climate fluctuations) and information ecology (social learning within groups applied to natural problems). The form of population contact is also relevant, but lies at a deeper level -- which technological patterns may or may not be able to address.

Australia's The Age online has a story by Deborah Smith that gives a short report about excavations at Jerimalai rock shelter, East Timor:

A cave site in East Timor where people lived more than 42,000 years ago, eating turtles, tuna and giant rats, was unearthed by Sue O'Connor, head of archaeology and natural history at the Australian National University.

The article discusses the significance in terms of a possible demonstration that the Timor route was taken by early Australian colonists, rather than the northern route via Sulawesi -- although it by no means rules out the northern route.

There is the obligatory mention of nearby Flores:

Although the Jerimalai site is at least 42,000 years old, it could be much older, Dr O'Connor said, because this was the detection limit of the radiocarbon dating method used. She said the simple stone tools unearthed in the shelter were similar to those used by the species of hobbit-sized people who lived in a cave on the nearby island of Flores until 12,000 years ago.

But she was confident Jerimalai's inhabitants were modern humans, Homo sapiens, and not small-brained members of Homo floresiensis, because of the evidence for their sophisticated behaviour found in the dig. Fish such as tuna, for example, "could only have been captured in the deeper waters offshore using hooks, and probably also water craft", she said.

The find, however, raised big questions, such as why modern humans appeared to have bypassed Flores on their way to Timor. One possibility was that the hobbits were able to repel them.

Or, modern humans were on Flores and left their tools there...

Actually, the most important piece of evidence at this Timor site may be the exploitation of deep marine resources, because it really shows a sophistication of seagoing technology. This sophistication is quite consistent with the early habitation of the Bismarck Archipelago before 30,000 years ago.

These people were routinely going far from land in their watercraft. The habitation of these islands was not accomplished by happenstance floating on ersatz rafts; it was part of a systematic exploitation of a marine resource niche.

The relevance of the site for the initial colonization of Sahul depends on its date. At present, the evidence for human habitation of Australia is certainly older than 40,000 years, and apparently younger than 60,000. If humans reached Australia as early as 60,000 years ago, they could easily have filled it by 42,000 years ago. After all, people took only a few thousand years to fill the Americas from top to bottom. So if the site is only 42,000 years old, it might represent a complex seafaring culture that actually followed the first Australian colonists by a substantial degree, and may have played little role in the origins of the Australians.

On the other hand, if the site is much older than 42,000 years, or represents a culture with substantially older time depth, then it might well be closely linked to the first Australians. In which case we could probably infer that the initial habitation of Australia and New Guinea were events that involved a sophisticated and potentially rapid spread along the coasts, with later penetration into the interior.

A sophisticated seafaring modern human culture that dated to as early as 60,000 years would encompass almost all the time depth of the Liang Bua cave stratigraphy, by the way.