Homo luzonensis, Denisovans, Papuans and the the Australian Aborigines - more evidence from the deep past

Because of issues associated with my move to Armidale, it is some considerable time since I last reported on the continuing research into the deep human past, research that affects our understanding of Aboriginal history.

While I have been relatively off-line, regular commenter John B has been emailing me material. It now seems an appropriate point to bring that material on line. The long post that follows reports on three recent studies, concluding with a short discussion. My continued indebtedness to John B will be apparent.

Homo Luzonensis 

In April 2019, a group of researchers reported on the results of exploration at Calloa Cave in the Philippines, suggesting the discover of another hominin species that they named Homo luzonensis, dating to about 67,000 years ago.

The map from the paper is shown, including land that would have been revealed at various sea levels below the present. The abstract from the paper is set out below. 

"A hominin third metatarsal discovered in 2007 in Callao Cave (Northern Luzon, the Philippines) and dated to 67 thousand years ago provided the earliest direct evidence of a human presence in the Philippines. Analysis of this foot bone suggested that it belonged to the genus Homo, but to which species was unclear. Here we report the discovery of twelve additional hominin elements that represent at least three individuals that were found in the same stratigraphic layer of Callao Cave as the previously discovered metatarsal. These specimens display a combination of primitive and derived morphological features that is different from the combination of features found in other species in the genus Homo (including Homo floresiensis and Homo sapiens) and warrants their attribution to a new species, which we name Homo luzonensis. The presence of another and previously unknown hominin species east of the Wallace Line during the Late Pleistocene epoch underscores the importance of island Southeast Asia in the evolution of the genus Homo."
Florent Détroit, Armand Salvador Mijares, Julien Corny, Guillaume Daver, Clément Zanolli, Eusebio Dizon, Emil Robles, Rainer Grün & Philip J. Piper, A new species of Homo from the Late Pleistocene of the Philippines, Nature volume 568, pages 181–186 (2019) Published on-line 10 April 2019, accessed 22 October 2019 

That same day (10 April), BBC Science Paul Rincon provided a useful popular summary in Homo luzonensis: New human species found in Philippines.The article included this chart derived from the Smithsonian which I thought provided a useful graphic.

The BBC article as well as other commentary quotes Professor Chris Stringer, from London's Natural History Museum. For those who follow Twitter, Professor Stringer is an active tweeter - @ChrisStringer65.

John kindly sent me a press release apparently issued by Professor Stringer at the time. This is set out below. I have not been able to find a link to the original but have included it in full because of the overview it provides.

"Homo Luzonensis -  a new human species from island south east Asia

After the remarkable finds of the diminutive Homo floriensis were published in 2004, I said that the experiment in human evolution conducted on Flores could have been repeated on many of the other islands in the region. That speculation has seemingly been confirmed on the island of Luzon in the Philippines, nearly 3,000 km away. 13 fossil human remains - teeth, hand and foot bones, and part of a femur from at least 3 adults and immature individuals have been recovered from excavations at Callao Cave since 2007. They have been dated to at least 50,000 years old, are small in size, particularly the teeth, and they show a distinctive combination of primitive and and derived traits sufficient for the authors of the paper in Nature to create a new human species for them: Homo luzonensis. They suggest that some of the hand and foot bones show features also present in much more ancient australopiths ("southern apes") found in Africa, and interpreted as adaptations for life in the trees.

So, do these finds really represent a new species, and what do they add to the story of human evolution? Given the small size of the sample, some scientists will question the wisdom of creating a new species based on such limited material, while others such as me wonder whether Luzon find might eventually turn out to be a variant of the already known Homo floresiensis, despite some clear differences. And we know that island isolation can be a catalyst for some odd evolutionary changes, including reversion to apparently primitive states. Nevertheless, for the moment, it is probably reasonable to accept the new species, at least provisionally, while awaiting more finds.

As for its origins and fate, they remain mysterious. As with floresiensis, expert opinion will probably be divided. Some will argue that the primitive features of luzonensis are evidence of a pre- Homo erectus dispersal out of Africa, perhaps more than 2 million years ago. floresiensis and luzonensis would represent some of the last survivors of that early wave, lingering on at the fringes of the inhabited world. Others would prefer to regard these island forms as descendants of Homo erectus, subject to isolation and island dwarfing over a considerable period of time. And given two such populations in the remote islands of south east Asia, others like me might consider they represent remnants of a dispersal of an original floresiensis or luzonensis -like founder lineage that originated somewhere like the island of Sulawesi. As for the fate of luzonensis, it is too early to say whether the spread of Homo sapiens into the region at least 50,000 years ago might have been factor in its disappearance, as has been suggested for floresiensis.

An extra layer of complexity in the region has been added by recent research on the Denisovans, an archaic population of humans originally identified from ancient DNA recovered from human fossils in Denisova Cave, Siberia. The additional existence of late Denisovan-like populations in south east Asia had been inferred from the presence of related DNA in extant Asian and Oceanian people, but recent research indicates at least three separate and varied Denisovan-like sources, at least one of which probably lived in the same wide biogeographic zone as floresiensis and luzonensis. We are currently far from establishing which fossils in the region might represent such populations, but it is probable that the spread of Denisovan-like people into the region was a separate and much later event than those involving floresiensis and luzonensis." Ends

Another who commented on the Luzon discoveries was Professor John Hawks. His New species of hominin from Luzon appeared on  his blog on 10 April 2019 and in the online journal Sapiens at the same time. It covers some of the same ground as Professor Stringer's comment, but with more focus on the details of the evidence.

Multiple Deeply Divergent Denisovan-related ancestries in Papuans 

 At the same time as the Luzonensis results were reported,  another paper was released in Cell entitled Multiple Deeply Divergent Denisovan-related ancestries in Papuans. 

The abstract reads:

"Genome sequences are known for two archaic hominins-Neanderthals and Denisovans-which interbred with anatomically modern humans as they dispersed out of Africa. We identified high-confidence archaic haplotypes in 161 new genomes spanning 14 island groups in Island Southeast Asia and New Guinea and found large stretches of DNA that are inconsistent with a single introgressing Denisovan origin. Instead, modern Papuans carry hundreds of gene variants from two deeply divergent Denisovan lineages that separated over 350 thousand years ago. Spatial and temporal structure among these lineages suggest that introgression from one of these Denisovan groups predominantly took place east of the Wallace line and continued until near the end of the Pleistocene. A third Denisovan lineage occurs in modern East Asians. This regional mosaic suggests considerable complexity in archaic contact, with modern humans interbreeding with multiple Denisovan groups that were geographically isolated from each other over deep evolutionary time."
Jacobs GS, Hudjashov G, Saag L, Kusuma P, Darusallam CC, Lawson D, Mondal M, Pagani L, Ricaut FX, Stoneking M, Metspalu M, Sudoyo H, Lansing JS, Cox MP, Multiple Deeply Divergent Denisovan-related ancestries in Papuans, Cell. 2019 May 2;177(4):1010-1021.e32. doi: 10.1016/j.cell.2019.02.035. Epub 2019 Apr 11.Accessed 23 October 2019

On 11 April, EuekaAlert carried a press release from the Max Planck Institute for Evolutionary Anthropology. I have set this out below in full because it provides another perspective.

"Multiple Denisovan-related ancestries in Papuans 
 DNA sequences from Indonesia and New Guinea reveal new branches of the Denisovan family tree

   The findings are based on a new study led by Murray Cox from Massey University in New Zealand and made possible by sampling efforts led by Herawati Sudoyo from the Eijkman Institute for Molecular Biology in Jakarta, Indonesia. The data were collected and analyzed by an international team of researchers, including Mark Stoneking from the Max Planck Institute for Evolutionary Anthropology. Taken together with previous work - which has pointed to a third Denisovan lineage in the genomes of modern Siberians, Native Americans, and East Asians - the evidence "suggests that modern humans interbred with multiple Denisovan populations, which were geographically isolated from each other over deep evolutionary time," the researchers write.

The new evidence also unexpectedly shows extra mixing between Papuans and one of the two Denisovan groups, suggesting that this group actually lived in New Guinea or its adjacent islands. Moreover, Denisovans may have lived in the area until as recently as 30,000 years ago, making them one of the last surviving groups of archaic hominins. "People used to think that Denisovans lived on the Asian mainland and far to the north," says Cox. "Our work instead shows that the center of archaic diversity was not in Europe or the frozen north, but instead in tropical Asia." Stoneking adds, "Moreover, this archaic diversity seems to have persisted much longer in Island Southeast Asia and New Guinea than elsewhere in the world."

It had already been clear that Island Southeast Asia and New Guinea was a special place, with individuals there carrying more archaic hominin DNA than anywhere else on Earth. The region was also recognized as key to the early evolution of Homo sapiens outside Africa. But there were gaps in the story.

Divergent Denisovan lineages

To help fill those gaps, the team identified stretches of archaic DNA from 161 new genomes spanning 14 island groups in Island Southeast Asia and New Guinea. Their analyses uncovered large stretches of DNA that did not jibe with a single introgression of genes from Denisovans into humans in the region. Instead, they report, modern Papuans carry hundreds of gene variants from two deeply divergent Denisovan lineages. In fact, they estimate that those two groups of Denisovans had been separated from one another for 350,000 years.

The new findings highlight how "incredibly understudied" this part of the world has been, the researchers say. To put it in context, many of the study's participants live in Indonesia, a country the size of Europe that is the 4th largest country in the world based on population size. And yet, apart from a handful of genome sequences reported in a global survey of genomic diversity in 2016, the new paper reports the first Indonesian genome sequences. There also has been a strong bias in studies of archaic hominins toward Europe and northern Eurasia, because DNA collected from ancient bones survives best in the cold north.

Missing data bias scientific interpretation

This lack of global representation in both ancient and modern genome data is well noted, the researchers say. "However, we don't think that people have really grasped just how much of a bias this puts on scientific interpretations - such as, here, the geographical distribution of archaic hominin populations," Cox says.

As fascinating as these new findings are, the researchers say their primary aim is to use this new genomic data to help improve healthcare for people in Island Southeast Asia. They say this first genome survey in the region now offers the baseline information needed to set that work in motion." Ends

Adaptive archaic introgression of copy number variants and the discovery of previously unknown human genes    

On 18 October 2019, Science published another study under the catchy (!) title Adaptive archaic introgression of copy number variants and the discovery of previously unknown human genes. The above graphic reproduced from the article provides an effective schematic.

In this case, I am not providing the full abstract (you will find it here) because of length as well as complexity. However, a short extract follows:

"Copy number variants (CNVs) are subject to stronger selective pressure than single-nucleotide variants, but their roles in archaic introgression and adaptation have not been systematically investigated. We show that stratified CNVs are significantly associated with signatures of positive selection in Melanesians and provide evidence for adaptive introgression of large CNVs at chromosomes 16p11.2 and 8p21.3 from Denisovans and Neanderthals, respectively. Using long-read sequence data, we reconstruct the structure and complex evolutionary history of these polymorphisms and show that both encode positively selected genes absent from most human populations. Our results collectively suggest that large CNVs originating in archaic hominins and introgressed into modern humans have played an important role in local population adaptation and represent an insufficiently studied source of large-scale genetic variation."
PingHsun Hsieh, Mitchell R. Vollger, Vy Dang, David Porubsky, Carl Baker, Stuart Cantsilieris, Kendra Hoekzema1, Alexandra P. Lewis, Katherine M. Munson, Melanie Sorensen, Zev N. Kronenberg, Shwetha Murali, Bradley J. Nelson1, Giorgia Chiatante, Flavia Angela Maria Maggiolini, Hélène Blanché, Jason G. Underwood, Francesca Antonacci, Jean-François Deleuze, Evan E. Eichler, Adaptive archaic introgression of copy number variants and the discovery of previously unknown human genes, Science  18 Oct 2019:Vol. 366, Issue 6463, eaax2083 DOI: 10.1126/science.aax2083, accessed 22 October 2019

Discussion

In sending me material, John B commented (24 April 2019): "It is increasingly looking likely Jim that the Aboriginals who first colonised Australia were locals to the region and not in transit through it, my suspicions of the original Out of Africa single origin hypothesis, replacement hypothesis, or recent African origin model continue to be confirmed. Archaic diversity, I do like that descriptor and the picture it conveys."

John and I have been talking about these issues now for a number of years. Over that time, new research discoveries have added to our understanding, but also created an unexpectedly complex and uncertain  picture. 

In 2017, reports of results from the excavations at the Madjedbebe rock shelter, The lessons and questions from Madjedbebe, pushed back the date of human occupation of Northern Australia to perhaps 65,000. I was going to write Aboriginal occupation but, while it seems probable, we don't actually know that the continent of Sahul was first occupied by the descendants of today's Aboriginal Australians.

In October 2016 in a paper entitled A genomic history of Aboriginal Australia, by Anna-Sapfo Malvinas, Michael C Westerway et all, the authors concluded that:

• Aboriginal Australians and Papuans diverged from Eurasians and estimate 51–72 kya, following a single out-of-Africa dispersal, and subsequently admixed with archaic populations
• Papuan and Aboriginal Australian ancestors diversified 25–40 thousand years ago (kya), suggesting pre-Holocene population structure in the ancient continent of Sahul (Australia, New Guinea and Tasmania). However, all of the studied Aboriginal Australians descend from a single founding population that differentiated ~10–32 kya
• We infer a population expansion in northeast Australia during the Holocene epoch (past 10,000 years) associated with limited gene flow from this region to the rest of Australia, consistent with the spread of the Pama–Nyungan languages.   

I will leave aside the last conclusion for it raises another set of issues that is important to the history of Aboriginal Australia but is outside the scope of this post.

At the time, the estimate of 51–72 kya for divergence from Eurasians following a single out-of-Africa dispersal made me uncomfortable because the archaeological evidence was already suggesting possible early dates for human occupation of Sahul that might possibly conflict with these time lines. The Madjedbebe results added to this discomfort: the suggested 65,000 years was remarkably close to the suggested 72kya out of Africa date.

Before going on, I note that all the dating techniques involve statistical analysis with confidence intervals. Apparent differences and inconsistencies may reflect no more than this.

 The latest discoveries covered in this blog post suggest that:

• Earlier hominum species were in South East Asia long before modern humans
• Those species had come in different waves and had diversified 
• Those species had crossed the Wallace Line, overcoming sea barriers. They may even have reached Sahul
• Those species and modern humans overlapped far more than previously realised, co-existing in various forms of relationships including inter-breeding
• Aboriginal and Papuan groups that formed the basis of later population may have lived in what is now SE Asian for extended periods before moving on, not just passing through.

In writing to me, John also noted:

"I have just been reading a Geology paper that mentioned the super volcano Toba eruption as the largest single event of its type so far known. It struck me that this could have been the event to precipitate human migration into Australia. We now understand that the arrival of H.sapiens into Oz occurred most likely as a bulk entry over a very short period then nobody else over millennia. Could Toba have been the push factor ?"

I am not convinced that there was a single pulse and am generally sceptical of attributions to volcanic eruptions. But still. As dates get pushed back, the possibility that the Toba eruption played a role in the movement of and ending of human species becomes more plausible! 

New evidence on the Neanderthal/Denisovan overlap

Summary timeline for the archaeology, hominin fossils and hominin DNA retrieved from the sediments at Denisova Cave. All age ranges are shown at the 95.4% confidence interval. Bert Roberts,

Interesting paper by Zenobia Jacobs, Bo Li, Kieran O'Gorman and Richard Roberts all from the University of Wollongong in The Conversation:  Fresh clues to the life and times of the Denisovans, a little-known ancient group of humans (31 January 2018) .

The Denisova site is interesting because it is the only known site so far for the Denisovan species of hominin, the only site where Denisovans and Neanderthals overlapped. The latest dating results are summarised this way.

 The new studies show that hominins have occupied the site almost continuously through relatively warm and cold periods over the past 300,000 years, leaving behind stone tools and other artefacts in the cave deposits. 

Fossils and DNA traces of Denisovans are found from at least 200,000 to 50,000 years ago, and those of Neanderthals from between 200,000 and 100,000 years ago. The girl with mixed ancestry reveals that the two groups of hominins met and interbred around 100,000 years ago.

Both the Aborigines and Papuans have significant traces of Denisovan DNA suggesting that their ancestors met and mixed with the Denisovans on their journey to Sahul. An alternative but still less likely explanation is that the Denisovans had already reached Sahul at least in small numbers and the admixture occurred here.

I say this only because there is now an apparent tension that I do not understand between the archaeological dates and those generated by DNA analysis. The first presently suggests earliest occupation of perhaps 62,000 years ago based on archaeological dating, while the second suggests an out of Africa date for the Aborigines and Papuans of perhaps 51-72,000 years based on DNA modelling. There is still an overlap, but it has become too small for my comfort. .

I think that what is clear is that the new evidence is progressively changing our understanding of the human pattern of settlement in Eurasia and that this will necessarily change our understanding of Sahul's history.

Climate deteriorations and Neanderthal demise in interior Iberia - a note

Interesting paper by Wolf, Kolb et al on the impact of climate change and Neanderthal demise in interior Iberior. The abstract reads:

Time and circumstances for the disappearance of Neanderthals and its relationship with the advent of Modern Humans are not yet sufficiently resolved, especially in case of the Iberian Peninsula. Reconstructing palaeoenvironmental conditions during the last glacial period is crucial to clarifying whether climate deteriorations or competition and contacts with Modern Humans played the pivotal role in driving Neanderthals to extinction. A high-resolution loess record from the Upper Tagus Basin in central Spain demonstrates that the Neanderthal abandonment of inner Iberian territories 42 kyr ago coincided with the evolvement of hostile environmental conditions, while archaeological evidence testifies that this desertion took place regardless of modern humans’ activities. According to stratigraphic findings and stable isotope analyses, this period corresponded to the driest environmental conditions of the last glacial apart from an even drier period linked to Heinrich Stadial 3. Our results show that during Marine Isotope Stages (MIS) 4 and 2 climate deteriorations in interior Iberia temporally coincided with northern hemisphere cold periods (Heinrich stadials). Solely during the middle MIS 3, in a period surrounding 42 kyr ago, this relation seems not straightforward, which may demonstrate the complexity of terrestrial climate conditions during glacial periods. 

D. Wolf, T. Kolb, M. Alcaraz-Castaño, S. Heinrich, P. Baumgart, R. Calvo, J. Sánchez, K. Ryborz, I. Schäfer, M. Bliedtner, R. Zech, L. Zöller & D. Faust, "Climate deteriorations and Neanderthal demise in interior Iberia", Scientific Reports,volume 8, Article number: 7048 (2018) doi:10.1038/s41598-018-25343-6 Received: 20 September 2017, Accepted 17 April 2018, Published 04 May 2018

Discussion

One of the issues we have discussed here that also came up in discussion during my recent Armidale seminar paper is the need to properly understand local variations in climatic conditions during the Pleistocene and Holocene if we are to understand the Aboriginal history of New England.

This paper makes the same point in a different context. The abstract is fairly dry (the full paper is on-line: link above), but a key point from the paper can be summarised this way: interior Iberia (modern Spain) became very dry and inhospitable with reduced vegetation at particular periods. One period coincided with Neanderthal occupation. It seems that the Neanderthals were not wiped out,  but may have retreated to coastal refuge areas where conditions were more benign. .

During glacial periods, the climate became drier as well as colder because so much water was tied up in ice. However, there were considerable variations at local level. For example, research results from the Little Llangothlin lagoon on the high New England suggest local variations during the Late Glacial Maximum that do not quite fit with the conventional analysis.

I now have a mass of new reading to do and to report on!

Cheddar Man revisited - More hype and complexity

Back in 2007 (Continuity in the face of great change - the case of Cheddar Man 5 April 2007) I reported on DNA results from  Bryan Sykes of Oxford University on Cheddar Man, the human skeleton of a Mesolithic hunter-gatherer found in 1903 in Gough's Cave in the English Cheddar district.

I was reminded of this last night while watching a British National History Museum video on the latest DNA analysis of Cheddar Man. I therefore went back and found the earlier post. Boy, do I feel a little silly.

To explain this, this is an excerpt from what I wrote at the time:

When I first studied what was then called English history, there is another interesting story in the use of this name, I was struck by the constant waves of invasion. I suppose I assumed, I know that I assumed, that this meant the replacement of one group of people by another, essentially extinguishing the earlier group. We now know that this is not true because of the rather remarkable case of Cheddar Man. 

In 1903 the complete skeleton of a human male was excavated from Gough's Cave in Cheddar Gorge, Somerset, hence the name Cheddar man. We now know that the remains date to approximately 7150 BCE, at least three thousand years before the advent of agriculture in the area. It appears that he died a violent death, perhaps related to the cannibalism practiced in the area at the time. 

In the late 1990s, Bryan Sykes of Oxford University sequenced the mitochondrial DNA of Cheddar Man with DNA extracted from one of Cheddar Man's molars. He then, and this is something that I suspect that I would have regarded as a gimmick, tested the DNA of a sample of twenty residents of the modern Cheddar village. He found two exact matches plus one very close match. 

Leaving aside the excitement of the two school children who gave the exact match and probably have the oldest scientifically established family tree in the world, the results show that Cheddar Man's family continued to reside in the same locality for perhaps 350 generations, surviving through all the invasions and changes. 

It also made me wonder about the role that DNA testing might play if we could do it in the appropriate way in extending our knowledge of Australia's Aboriginal past. 

We know that Aboriginal populations were not static, but shifted over time. We do not really understand those shifts.

I was right, of course, on the potential role that DNA tests might might play in increasing our understanding of the deep Aboriginal past, but I seem to have really jumped to uncritical conclusions on Cheddar Man. I also did not give my own sources in that original post, although it was based on news reports.

The results of the latest research is summarised in these stories:

• Kerry Lotzof, Cheddar Man: Mesolithic Britain's blue-eyed boy, National History Museum
• Jennifer Hassan, Meet Cheddar Man: First modern Britons had dark skin and blue eyes. Washington Post
• Paul Rincon,Cheddar Man: DNA shows early Briton had dark skin, BBC 
• Robin McKie, Cheddar Man changes the way we think about our ancestors, The Guardian
• Tim Collins, Was Cheddar man white after all? There's no way to know that the first Briton had ‘dark to black skin’ says scientist who helped reconstruct his 10,000-year-old face, Daily Mail. The Daily Mail gives a link through to research results, Population Replacement in Early Neolithic Britain

The results have attracted major media attention because the DNA results suggest that Cheddar Man was dark skinned, More precisely, the probability is that he was dark skinned. He was also lactose intolerant. The Museum summary states in part:  .

Modern-day British people share approximately 10% of their genetic ancestry with the European population to which Cheddar Man belonged, but they aren't direct descendants. 

Current thinking is that the Mesolithic population that Cheddar Man belonged to was mostly replaced by the farmers that migrated into Britain later.  

Now how do we relate this to the conclusions in my earlier post?

Well, first of all, considerable doubt has been cast on Professor Sykes original results. The new results are consistent with the earlier picture of multiple invasions. They also, I think, provide hints at the merging of populations over time. Beyond that, I am not sure!

The National Museum video, though, is worth watching as an introduction to the painstaking world of research and the results that can arise.For my part, I will leave the original post standing because it represents part of the evolution of my own thinking over eleven years, but add a qualification and link to this post.

Comments that might elucidate and educate me are very welcome! .

Skara Brae: local responses to environmental change

Interesting piece in Nature Ecology & Evolution, The resilience of postglacial hunter-gatherers to abrupt climate change, on the Skara Brae site (photo) in Scotland published on-line on 26 march 2018.

I will give you the abstract first and then make a brief comment. The abstract reads:

Understanding the resilience of early societies to climate change is an essential part of exploring the environmental sensitivity of human populations. There is significant interest in the role of abrupt climate events as a driver of early Holocene human activity, but there are very few well-dated records directly compared with local climate archives. Here, we present evidence from the internationally important Mesolithic site of Star Carr showing occupation during the early Holocene, which is directly compared with a high-resolution palaeoclimate record from neighbouring lake beds. We show that—once established—there was intensive human activity at the site for several hundred years when the community was subject to multiple, severe, abrupt climate events that impacted air temperatures, the landscape and the ecosystem of the region. However, these results show that occupation and activity at the site persisted regardless of the environmental stresses experienced by this society. The Star Carr population displayed a high level of resilience to climate change, suggesting that postglacial populations were not necessarily held hostage to the flickering switch of climate change. Instead, we show that local, intrinsic changes in the wetland environment were more significant in determining human activity than the large-scale abrupt early Holocene climate events. 

Simon Blockley, Ian Candy, Ian Matthews, Pete Langdon, Cath Langdon, Adrian Palmer, Paul Lincoln, Ashley Abrook, Barry Taylor, Chantal Conneller, Alex Bayliss, Alison MacLeod, Laura Deeprose, Chris Darvill, Rebecca Kearney, Nancy Beavan, Richard Staff, Michael Bamforth, Maisie Taylor & Nicky Milner The resilience of postglacial hunter-gatherers to abrupt climate change Nature Ecology & Evolution (2018)
doi:10.1038/s41559-018-0508-4

The resilience of human populations to survive in the face of extreme change will not come as a surprise to anybody who knows something about the Tasmanian Aborigines. By the time that Skara Brae was established, Tasmania's Aboriginal peoples had survived the Late Glacial maximum and the separation of Tasmania from the mainland. They were affected by but adapted to dramatic climate change.

All this said. the Skara Brae case illustrates the importance of understanding the local effects of change and the nature of responses. I know that I am a broken record on this one. .

Dendrochronology and the discovery of the Late Antique Little Ice Age

I first came across dendrochronology when I was studied prehistory and archaeology in my undergraduate degree. Since then, the field has exploded.

Wikipedia describes dendrochronology in these terms:

Dendrochronology (or tree-ring dating) is the scientific method of dating tree rings (also called growth rings) to the exact year they were formed in order to analyze atmospheric conditions during different periods in history. Dendrochronology is useful for determining the timing of events and rates of change in the environment (most prominently climate) and also in works of art and architecture, such as old panel paintings on wood, buildings, etc. It is also used in radiocarbon dating to calibrate radiocarbon ages. 

New growth in trees occurs in a layer of cells near the bark. A tree's growth rate changes in a predictable pattern throughout the year in response to seasonal climate changes, resulting in visible growth rings. Each ring marks a complete cycle of seasons, or one year, in the tree's life As of 2013, the oldest tree-ring measurements in the Northern Hemisphere are a floating sequence extending from about 12,580 to 13,900 years.

A very user friendly description by Matthew Mason can be found in Environment Science: Dendrochronology: What Tree Rings Tell Us About Past and Present.

As indicated, dendrochronology can be used in dating including the calibration of radio carbon dates. However, variations in the tree rings can also provide evidence for climatic variation. This February 2018 Cambridge University promo, Silent witnesses: how an ice age was written in the trees, describes a little of the work being done here focused especially on the discovery of LALIA, the Late Antique Little Ice Age which dated from AD 536 to around AD 660.

The promo references a 2016 letter published in Nature Geoscience, Cooling and societal change during the Late Antique Little Ice Age from 536 to around 660 AD.. The abstract follows. Details of the footnotes can be found in the original. :

Climatic changes during the first half of the Common Era have been suggested to play a role in societal reorganizations in Europe 1,2 and Asia 3,4. In particular, the sixth century coincides with rising and falling civilizations 1,2,3,4,5,6, pandemics 7,8, human migration and political turmoil 8,9,10,11,12,13. Our understanding of the magnitude and spatial extent as well as the possible causes and concurrences of climate change during this period is, however, still limited. Here we use tree-ring chronologies from the Russian Altai and European Alps to reconstruct summer temperatures over the past two millennia. We find an unprecedented, long-lasting and spatially synchronized cooling following a cluster of large volcanic eruptions in 536, 540 and 547 AD (ref. 14), which was probably sustained by ocean and sea-ice feedbacks 15,16, as well as a solar minimum 17. We thus identify the interval from 536 to about 660 AD as the Late Antique Little Ice Age. Spanning most of the Northern Hemisphere, we suggest that this cold phase be considered as an additional environmental factor contributing to the establishment of the Justinian plague 7,8, transformation of the eastern Roman Empire and collapse of the Sasanian Empire 1,2,5, movements out of the Asian steppe and Arabian Peninsula 8,11,12, spread of Slavic-speaking peoples 9,10 and political upheavals in China 13.

Ulf Büntgen, Vladimir S. Myglan, Fredrik Charpentier Ljungqvist, Michael McCormick, Nicola Di Cosmo, Michael Sigl, Johann Jungclaus, Sebastian Wagner, Paul J. Krusic, Jan Esper, Jed O. Kaplan, Michiel A. C. de Vaan, Jürg Luterbacher, Lukas Wacker, Willy Tegel & Alexander V. Kirdyanov "Cooling and societal change during the Late Antique Little Ice Age from 536 to around 660 AD".. Nature Geoscience volume 9, pages 231–236 (2016) doi:10.1038/ngeo2652

Discussion

One of my weaknesses when I first started studying history at school and then as an undergraduate is that I underestimated the importance of variations across space and time in environmental conditions. I became much more conscious of these issues when I started Aboriginal history. Even the, I had unconscious blind spots.  As a simple and much later example, until I visited the Greek Islands in 2010 I really had no idea of the importance of water, food production and transport to life and politics on particular islands. Perhaps more precisely, I knew in an abstract sense but hadn't made the concrete connection.

As we gain more knowledge of the past, our views shift. The knowledge that the still new colony at Port Jackson was hit by an El Nino event that counters a previously prevailing view that its food problems were primarily due to lack of knowledge of soil and farming techniques in a new land.

The discovery from dendrochronology of the Late Antique Little Ice Age, although I'm not sure that I buy all the hype attache, is actually exciting. Here we have a case of difficulties that were identified in the documentary record but that, like the Sydney example, lacked a context to interpret them in a coherent way.      

Billy Griffiths, Isabel McBryde and Deep Time Dreaming - a note

On Saturday 17 March 2018, ABC's Radio National Geraldine Doogue interviewed Billy Griffith, the author of Deep Time Dreaming: Uncovering Ancient Australia. (Black Inc, February 2018).

Billy is a historian and research fellow at the Alfred Deakin Institute for Citizenship and Globalisation. In his book, he explores a twin revolution: the reassertion of Aboriginal identity in the second half of the twentieth century, and the simultaneous uncovering of the traces of ancient Australia by pioneering archaeologists.

The ABC interview is on-line and well worth listening too.An excerpt from the book telling the story of archaeologist Isabel McBryde, Haunted Country, was published in Inside Story. It is well written and will give you a feel for the book as a whole. It is also an excerpt of particular relevance to me because I was one of that group of Isabel's students that Billy talks about.

I have written a little on all this, material that I need to consolidate. Billy's assessment is to a degree limited by space and focus.This does not detract from its value, it's a very good piece indeed, but means that it does not fully reflect the scope of Isabel's work.

John Mulvaney, Isabel's mentor, has been described as the Father of Australian archaeology, while. Trowelblazers described  Isabel as the mother. Leaving aside a certain feeling of discomfort about the use of such gender specific terms, it does reflect her importance and influence.

In a paper delivered in 2010, Unrecognised and now almost unknown: explorations through the history of the broader New England, I described Isabel's contribution to the University of New England in this way:

" Isabel’s personality and approach exactly fitted the University’s culture. The results were quite outstanding for such a small institution.

Four years after Isabel’s arrival came the first thesis, Sharon Sullivan's 1964 honours study on the material culture of the Aborigines of the Richmond and Tweed Rivers.

By 1978, UNE students had written at least 22 theses on the Aborigines, 4 Litt.B's, 16 BA honours and 2 MAs. Isabel herself was awarded her PhD in 1967, laying the basis for a 1974 book, Aboriginal prehistory in New England. This was followed in 1978 by book of essays, Records of Time Past: ethnohistorical essays on the culture and ecology of the New England tribes mainly written by her former students. This included an article of mine, Population distribution and the pattern of seasonal movement in Northern NSW, drawn from my original work. The story does not end there, for there were also journal articles and monographs, including her pioneering study with R A Binns, A petrological analysis of ground-edge artefacts from northern New South Wales.

The citation for her award in 2003 of the Rhys Jones Medal for Outstanding Contribution to Australian Archaeology justly summarised her work this way:

Her work in New England was remarkable for its extent and depth, and Isabel's examination of the interface of archaeology and ethnography in the region shaped not only the approach taken by many later researchers but also prepared the basis for the arguments about upland regions created by archaeologists such as Sandra Bowdler and Luke Godwin."

It is now 55 years since I first became involved as a student with Isabel. My career choices took me well away from archaeology, prehistory or Aboriginal studies.Still, here I am 55 years later trying to develop a new synthesis for New England Aboriginal history. That's a remarkable reach.  

New questions on the origin and spread of Australia's Aboriginal languages

Proposed Australian language tree

A University of Newcastle (UON) news item published on 21 March 2018, Indigenous language link reveals common ancestor, reported on new research on the history and structure of Australia's Aboriginal languages. As I have done before, I provide the information first while comments follow at the end.

The University of Newcastle piece reads:

"New research has found a ground-breaking link between Australian Indigenous languages, demonstrating for the first time that all Indigenous languages descend from one common ancestor. 

The unprecedented finding sheds new light on the origins of Australian language and has significant implications for the cultural history of Australia.

The result of a collaboration between the University of Newcastle (UON) and Western Sydney University (WSU), the finding is the first time the theory that all Australian languages derive from one language, Proto-Australian, has been proven. 

UON Chief Investigator and historical linguist, Associate Professor Mark Harvey, said the finding was an exciting culmination of a three-year project, which he hoped would enhance the understanding of Australian and human history. 

“Until now, it was speculated that Australia was significantly more linguistically diverse than somewhere like Europe, because it had not been proven that all Australian languages actually stemmed from the same lineage. 

“This is the first demonstration that all Australian languages are part of the same language family. This language family spread across all of Australia, presumably from a small area in Northern Australia. This spread is likely to have been carried out by at least some population movement whose material and genetic traces have remained somewhat elusive. 

“However, with further interdisciplinary research, this new linguistic evidence is likely to give us a more precise reconstruction of Australian prehistory from what is currently known,” Associate Professor Harvey said. 

The project used the standard method in historical linguistics to establish whether similarity between languages was due to inheritance from a common ancestor, as opposed to transfer from one language to another through human contact or chance. 

WSU Chief Investigator, Associate Professor Robert Mailhammer, said the findings revealed recurrent similarities between languages that were not in contact. 

“We discovered that the sounds of words we compared showed recurrent systematic differences and similarities across a set of languages that are spread out in a geographically discontinuous way, which makes it very unlikely that they are the result of chance or language contact,” Associate Professor Mailhammer said. 

While a multitude of Australian Aboriginal and Torres Strait Islander languages were spoken at the time of European settlement, the findings also imply that Indigenous Australian languages only spread after the end of the last ice age, some 10-12,000 years ago. 

“These findings show that Indigenous Australian languages were not the likely languages spoken by the first inhabitants of Australia, raising more questions around how the languages spread and how the linguistic findings connect to the genetic findings,” Associate Professor Mailhammer added. 

Both researchers recognise that work in this area will continue, with plans to publish a book on Proto-Australian and collaborate with other disciplines to inform what is known about the prehistory of Australia. 

Funded under an Australian Research Centre (ARC) 2014 Discovery Project, the key research was published in the leading journal of historical linguistics, Diachronica. 

Researching in the field of Indigenous language, Dr Raymond Kelly from the University of Newcastle’s PURAI Global Indigenous and Diaspora Research Studies Centre said the findings would come as a welcome relief to many first nation people in the state of New South Wales (NSW) working at the coal face of language reconstruction, revival and renewal programs. 

“During the course of research for my own PhD, I also developed a similar conviction that Aboriginal languages in NSW are formed or drawn from a single source and expand beyond the state and territorial boundaries that we know exist today. These findings provide a healthy opportunity to re-evaluate the concept of connection and relationship for community,” Dr Kelly said."

The abstract of the :Diachronica article, the full article is behind a paywall,  reads:

"Evaluation of hypotheses on genetic relationships depends on two factors: database size and criteria on correspondence quality. For hypotheses on remote relationships, databases are often small. Therefore, detailed consideration of criteria on correspondence quality is important. Hypotheses on remote relationships commonly involve greater geographical and temporal ranges. Consequently, we propose that there are two factors which are likely to play a greater role in comparing hypotheses of chance, contact and inheritance for remote relationships: (i) spatial distribution of corresponding forms; and (ii) language specific unpredictability in related paradigms. Concentrated spatial distributions disfavour hypotheses of chance, and discontinuous distributions disfavour contact hypotheses, whereas hypotheses of inheritance may accommodate both. Higher levels of language-specific unpredictability favour remote over recent transmission. We consider a remote relationship hypothesis, the Proto-Australian hypothesis. We take noun class prefixation as a test dataset for evaluating this hypothesis against these two criteria, and we show that inheritance is favoured over chance and contact". 

Mark Harvey and Robert Mailhammer, Reconstructing remote relationships, Diachronica, Volume 34, Issue 4, 2017, pp 470 –515, Published online 09 February 2018

Comment

In The origins of Pama-Nyungan - a note on the implications for the history of New England's Aboriginal peoples (13 March 2018) I reported on new research by Professor Claire Bowern and her colleagues that concluded that all Pama-Nyungan languages, the dominant language family across Australia, emerged just under 6,000 years ago around what is now the Queensland town of Burketown and then spread across Australia as people moved in response to changing climate. This research appears consistent with those conclusions but goes further, suggesting that all Aboriginal languages were related to some common proto-language but only spread after the end of the last ice age, some 10-12,000 years ago.

My 13 March comment focused on the difficulty I was having in meshing the conclusions of  Professor Claire Bowern and her colleagues with my evolving conclusions on New England Aboriginal history. A particular difficulty was the pattern of language diffusion and replacement given my evolving thoughts on Aboriginal retreat and resettlement during the Late Glacial Maximum (LGM) and following Holocene period. To restate my views:

• We have a range of dates from the Hunter Valley, Liverpool Plains and at Wallen Wallen in SE Queensland suggesting occupation during the late Pleistocene (17,000 to 22,000 years ago)
• The LGM (Late Glacial Maximum) forced populations to shift to survive. Parts of the North Coast were not very hospitable, so I postulated a retreat north and south.
• As the new coastal environment began to form, people returned. Inland, the population spread from refuge areas along the slopes and plains. The Tablelands constituted an initial barrier.As the climate eased further and the environment changed the Tablelands were resettled primarily from the coast, but also onto the slopes from the West. I think that this pattern is reflected in later language differences.
• In terms of the patchy dates we have, we have earliest settlement in the Macleay around 9,000 years ago, a date of over 6,000 years ago for Seelands in the Clarence, around 5,500 years ago for Graman on the western slopes. My feeling was that by around 6,000 years ago, reoccupation of territory after the LGM was well underway.  
• from around 4000 years ago the number of dates begins to accelerate with accelerated population increase.

.In the UON piece, the second researcher Professor Mailhammer states “These findings show that Indigenous Australian languages were not the likely languages spoken by the first inhabitants of Australia, raising more questions around how the languages spread and how the linguistic findings connect to the genetic findings,”

Then, in a comment on the findings, UON's Dr Kelly state that  they would come as a welcome relief to many first nation people in the state of New South Wales working at the coal face of language reconstruction, revival and renewal programs. He goes on: :

“During the course of research for my own PhD, I also developed a similar conviction that Aboriginal languages in NSW are formed or drawn from a single source and expand beyond the state and territorial boundaries that we know exist today. These findings provide a healthy opportunity to re-evaluate the concept of connection and relationship for community,” 

There is something of a tension between these views. The problem is that the linguistic evidence appears to be suggesting that the Aborigines in NSW/New England who survived the LGM were supplanted by/ absorbed by later groups. So the first nations of NSW may not be the first nations at all, but peoples who came millennia later. I'm not sure that that conclusion will provide much comfort.

Professor Mailhammer suggests that the research raises more questions around the way the languages spread and how the linguistic findings connect to the genetic findings. I think that we should add archaeological findings to the list.

Last year, I reported (When and where did the Australian Aborigines and the Denisovans meet? 17 September 2017) on a 2106 Nature article by Anna-Sapfo Malaspinas, Michael C. Westaway et al
A genomic history of Aboriginal Australia. The abstract to that paper reads:

"The population history of Aboriginal Australians remains largely uncharacterized. Here we generate high-coverage genomes for 83 Aboriginal Australians (speakers of Pama–Nyungan languages) and 25 Papuans from the New Guinea Highlands. We find that Papuan and Aboriginal Australian ancestors diversified 25–40 thousand years ago (kya), suggesting pre-Holocene population structure in the ancient continent of Sahul (Australia, New Guinea and Tasmania). However, all of the studied Aboriginal Australians descend from a single founding population that differentiated ~10–32 kya. We infer a population expansion in northeast Australia during the Holocene epoch (past 10,000 years) associated with limited gene flow from this region to the rest of Australia, consistent with the spread of the Pama–Nyungan languages. We estimate that Aboriginal Australians and Papuans diverged from Eurasians 51–72 kya, following a single out-of-Africa dispersal, and subsequently admixed with archaic populations. Finally, we report evidence of selection in Aboriginal Australians potentially associated with living in the desert."

As the title of my post indicates, my main focus was on the nature of DNA evidence and the linkages with the Denisovans. However, the broad conclusions as summarised in the abstract are broadly consistent with the latest linguistic evidence, with the spread of Pama–Nyungan by absorption and contact rather than occupation and replacement.  However, problems remain.

Since the Nature article was published, we have the latest results from the Madjedbebe Rock Shelter (The lessons and questions from Madjedbebe) pushing back the date of human occupation of Sahul to 62,000+ years ago.As noted before, on the assumption that the Aboriginal peoples were the first occupants a tension arises between the dates suggested by DNA analysis and those from archaeology. Further, each new piece of analysis suggested a far more complex picture in terms of out-of-Africa and the spread and mixing with other hominid species.

At this point I do not quite know what to think. I am documenting for later analysis and synthesis.

Was there a connection between India and Aboriginal Australia?

I had a brief discussion with regular commenter John on the evidence for possible DNA links between Australia and India. Checking, while I have briefly discussed this in the past, I didn't provide links. 

On 10 March 2016, Darren Curnoe had a useful piece in The Conversation, An Ancient Connection to India, summarising the evidence as it then stood. I have taken the liberty of reproducing the paper in full, in part because of the links. I have also added the full references attached to the main papers plus one additional reference that came out after Darren published.. 

As you will see from the paper, the question of a possible Indian connection is linked to disputes about the settling of the continent by the Aborigines, including the cause of what has been called intensification, changes in technology and population density that occurred some 5,000 or so years ago.

 My personal views conditioned by my New England thinking, by the evidence we have so far, can be summarised this way:

• There nothing in the archaeological record that I can see to support the idea of a sudden infusion of new technology associated with the arrival of a new group
• Aboriginal culture including the use of technology was not constant but changed over time depending on climate and resources
• To my mind, the most plausible explanation of the pattern of change that took place at the end of the Late Glacial Maximum is directly connected with population growth, new structures and new forms of working as the surrounding environment became more benign and favourable.

None of this means , however, that there was not some interconnection with, flow from, the Indian subcontinent that might have affected DNA structures. We will have to wait for the DNA experts to sort this out. .          

The paper

 

When was the remote Australian continent first settled? Where did these ancient Australians come from? Was the island settled once, or on multiple occasions? Is there a genealogical connection between the Indigenous people of Australia and India?

These are questions I’ve spent almost two decades cogitating, and some of them have been pondered now for almost 400 years by European scholars.

Way back in 1623, while on route through the Torres Strait, the Dutch explorer Jan Carstenz (or Carstenszoon) was the first to write about these issues in describing the physical appearance of Indigenous Australians.

He likened people in the north of the continent to so-called ‘Indians’ of the Coramandel of New Zealand, or Maori people of the North Island.

The descriptor ‘Indian’ was used widely in those days to refer to populations across the New World, and didn’t imply any genealogical relationship with South Asians as such; that connection would be made by Thomas Henry Huxley more than two centuries later.

Huxley was by far the most influential early European thinker about human origins. Champion of Darwin’s theory of evolution, as a young man Huxley visited Australia on the HMS Rattlesnake in 1847, 11 years after Darwin came here on the HMS Beagle.

While he showed little interest in anthropology at the time, he would subsequently go on to found human evolution science and strongly shape Darwin’s ideas about our origins.

In 1870, in On the Geographical Distribution of the Chief Modifications of Mankind, Huxley proposed that Indigenous Australians were closely related to the people of South Asia, confidently asserting:

‘the only people out of Australia who present the chief characteristics of the Australians in a well-marked form are the so-called hill-tribes who inhabit the interior of the Dekhan, in Hindostan.’

While based on speculation, rather remarkably, I think, his ideas would come to be influential up until the 1970s; only to be rekindled by geneticists in 1999.

One physical anthropologist who was especially influenced by Huxley’s musing was Joseph Birdsell. He worked in Australia from the 1940s, writing about the continent’s Indigenous people until his death in the 1990s.

Birdsell developed a model for the peopling of Australia proposing settlement in three waves; with people coming from Southeast Asia, followed by more people from Japan, and later from India; modern Indigenous people being a kind of mix of the three groups.

His model has been long discredited among anthropologists because it finds no support in fossilised human remains - the only physical evidence we have for the earliest people in Australia.

Moreover, his intellectual contemporary and rival, Andrew Abbie, failed to confirm Birdsell’s ideas during the extensive anthropological surveys he undertook with living Indigenous people across the continent.

Enter the geneticists Alan Redd and Mark Stoneking who in 1999 took a leaf out of Huxley’s writing and published evidence for a maternal genetic connection (1) between Australia and India.

1. Alan J.Redd, Mark Stoneking, Peopling of Sahul: mtDNA Variation in Aboriginal Australian and Papua New Guinean Populations, AJHG, Volume 65, Issue 3, September 1999, Pages 808-828

 

To bolster their ideas, they linked their findings to events seen in the archaeological record, especially the arrival of the dingo, as well as perceived language similarities and even Birdsell’s ideas about migration.

Redd and Stoneking suggested that people from India arrived in northern Australia sometime around three and a half thousand years ago and left a major genetic and cultural legacy with the Indigenous people of the Northern Territory today.

Their work deeply divided both the anthropological and genetic communities, opening old wounds and reviving discredited theories.

Some archaeologists had argued in the 1970s and 1980s that there was indeed a sudden change in the kinds of tools being made in northern Australia - known as the ‘Small Tool Tradition’ or ‘Backed Blades’ - broadly coincident with the arrival of the dog, and indicating the arrival of a new people.

Yet, Backed Blades were later shown to be present in archaeological deposits near Sydney dating back to about 8 thousand years old and in northern Queensland to around 15 thousand years old. The contradictory evidence was overlooked by Redd and Stoneking.

Their work was followed by more genetic studies supporting (2)  the hypothesis (3) and a range (4) of others seemingly (5) rejecting (6) it.

(2) Alan J.Redd, June Roberts-Thomson, Tatiana Karafet, Michael Bamsha, Lynn B.Jorde, J.M.Naidu, BruceWalsh, Michael F.Hammer, Gene Flow from the Indian Subcontinent to Australia: Evidence from the Y Chromosome, Current Biology, Volume 12, Issue 8, 16 April 2002, Pages 673-677

(3) Irina Pugach, Frederick Delfin, Ellen Gunnarsdóttir, Manfred Kayser and Mark Stoneking, Genome-wide data substantiate Holocene gene flow from India to Australia, PNAS 2013 January, 110 (5) 1803-1808. https://doi.org/10.1073/pnas.1211927110

(4) Georgi Hudjashov, Toomas Kivisild, Peter A. Underhill, Phillip Endicott, Juan J. Sanchez, Alice A. Lin, Peidong Shen, Peter Oefner, Colin Renfrew, Richard Villems and Peter Forster, Revealing the prehistoric settlement of Australia by Y chromosome and mtDNA analysis, PNAS 2007 May, 104 (21) 8726-8730. https://doi.org/10.1073/pnas.0702928104

(5) Brian P.McEvoy, Joanne M.Lind, Eric T.Wang, Robert K.Moyzis, Peter M.Visscher, Sheila M.van Holst Pellekaan, Alan N.Wilton,Whole-Genome Genetic Diversity in a Sample of Australians with Deep Aboriginal Ancestry,  AJHG, Volume 87, Issue 2, 13 August 2010, Pages 297-305

(6)  Morten Rasmussen, Xiaosen Guo, Yong Wang, Kirk E. Lohmueller, Simon Rasmussen, Anders Albrechtsen, Line Skotte, Stinus Lindgreen, Mait Metspalu, Thibaut Jombart , Toomas Kivisild, Weiwei Zhai, Anders Eriksson, Andrea Manica, Ludovic Orlando, Francisco M. De La Vega, Silvana Tridico, Ene Metspalu, Kasper Nielsen, María C. Ávila-Arcos, J. Víctor Moreno-Mayar, Craig Muller, Joe Dortch, M. Thomas P. Gilbert, Ole Lund, Agata Wesolowska, Monika Karmin, Lucy A. Weinert, Bo Wang, Jun Li, Shuaishuai Tai, Fei Xiao, Tsunehiko Hanihara, George van Driem, Aashish R. Jha, François-Xavier Ricaut, Peter de Knijff, Andrea B Migliano, Irene Gallego Romero, Karsten Kristiansen, David M. Lambert, Søren Brunak, Peter Forster, Bernd Brinkmann, Olaf Nehlich, Michael Bunce, Michael Richards, Ramneek Gupta, Carlos D. Bustamante, Anders Krogh, Robert A. Foley, Marta M. Lahr, Francois Balloux, Thomas Sicheritz-Pontén, Richard Villems, Rasmus Nielsen, Jun Wang, Eske Willerslev, An Aboriginal Australian Genome Reveals Separate Human Dispersals into Asia, Science  07 Oct 2011:

Vol. 334, Issue 6052, pp. 94-98 DOI: 10.1126/science.1211177

Then last month, the latest salvo against the India connection was launched and, I must confess, I may have greeted it a little too enthusiastically.

The work, led by Anders Bergström of the Wellcome Trust Sanger Institute, and published in Current Biology (7), fully sequenced and compared globally the Y-chromosomes of 13 Aboriginal Australian men.

(7) Anders Bergström, Nano Nagle, Yuan Chen, Shane McCarthy, Martin O.Pollard, Qasim Ayub, Stephen Wilcox, Leah Wilcox, Roland A.H.van Oorschot, Peter McAllister, Lesley Williams, Yali Xue. John Mitchell, Chris Tyler-Smith, Deep Roots for Aboriginal Australian Y Chromosomes, Current Biology, Volume 26, Issue 6, 21 March 2016, Pages 809-813

In a nutshell, their study found that Aboriginal men are descended from early modern human populations identified as living broadly across East Asia by at least 60 thousand years ago.

A subset of these people migrated to New Guinea and Australia, settling these areas by about 55 thousand years ago, according to genetic clocks.

The research has confirmed a large number of other genetic studies showing that soon after Australia was peopled, Indigenous New Guineans and Australians became isolated from each other, except in a few places in the north like the Torres Strait.

One paper published following publication of Darren's article also found no evidence of later Indian admixture. Anna-Sapfo Malaspinas, Michael C. Westaway[…]Eske Willerslev, A genomic history of Aboriginal Australia, Nature volume 538, pages 207–214 (13 October 2016) doi:10.1038/nature18299

 

A very ancient origin for Indigenous Australians is also supported by the human fossil and archaeological records showing an arrival at least 40-50 thousand years ago or more.

Even Redd and Stoneking and their subsequent supporters all agreed on these points.

Australia was also, according to last month’s research, peopled once, and only once, before Europeans came by the boat load from 1788. No signs of Indian gene flow here; contrary to Redd and Stoneking’s ideas.

Yes, there was certainly trade and contact with the outside world, such as with the Macassans from Sulawesi beginning in the 1600s. But it seems for the most part not to have left a genetic footprint among living Aboriginal people.

Now, all of this leaves really only the geneticists arguing over the India connection, and they seem to be coming at the question from quite different angles; despite using very similar kinds of evidence.

Why such strong disagreement? I think the simplest explanation is that we don’t yet have enough data to provide a clear answer, from the DNA or human fossil remains. Archaeology is clearly very important, but not the full picture.

Aboriginal Australians have without doubt been living here for tens of thousand of years, but whether they were completely (genetically) isolated until 1788 is not yet certain.

What about the dingo? The latest genetic research suggests it may have come from New Guinea or even directly from Taiwan by Austronesian speaking people, with no indications of India ancestry whatsoever.

The burden of proof lies with those proposing the idea of a link between some Indigenous Australians and far away India, because the alternative view is the one that receives support from other kinds of evidence.

Also, I think it’s way too easy to ‘cherry-pick’ the physical anthropology, linguistic and archaeological literature, as geneticists are prone to doing, when the picture emerging from all these areas of research is much more complicated than most geneticists would concede.

Still, we’ve come a long way since Huxley’s insightful speculation, and who know’s whether he’ll ultimately be proved right.

Further dating evidence sets context for Aboriginal occupation of Australia

Misliya Cave is part of a series of prehistoric cave sites located along the western slopes of Mount Carmel, Israel. An upper left jawbone with most of the teeth attached attributed to homo sapiens  has been dated to 177,000-194,000 years ago, pushing back the date at which modern humans left Africa. 

New research results continue to deepen our understanding of the hominin past.

In a piece in National Geographic (These Tools Upend Our View of Stone-Age Humans in Asia, 31 January 2018) Michael Gresko provides an overview of new research reported in Nature. The authors of that research summarise their results in this way: 

Luminescence dating at the stratified prehistoric site of Attirampakkam, India, has shown that processes signifying the end of the Acheulian culture and the emergence of a Middle Palaeolithic culture occurred at 385 ± 64 thousand years ago (ka), much earlier than conventionally presumed for South Asia.  The Middle Palaeolithic continued at Attirampakkam until 172 ± 41 ka. Chronologies of Middle Palaeolithic technologies in regions distant from Africa and Europe are crucial for testing theories about the origins and early evolution of these cultures, and for understanding their association with modern humans or archaic hominins, their links with preceding Acheulian cultures and the spread of Levallois lithic technologies. The geographic location of India and its rich Middle Palaeolithic record are ideally suited to addressing these issues, but progress has been limited by the paucity of excavated sites and hominin fossils as well as by geochronological constraints. At Attirampakkam, the gradual disuse of bifaces, the predominance of small tools, the appearance of distinctive and diverse Levallois flake and point strategies, and the blade component all highlight a notable shift away from the preceding Acheulian large-flake technologies. These findings document a process of substantial behavioural change that occurred in India at 385 ± 64 ka and establish its contemporaneity with similar processes recorded in Africa and Europe. This suggests complex interactions between local developments and ongoing global transformations. Together, these observations call for a re-evaluation of models that restrict the origins of Indian Middle Palaeolithic culture to the incidence of modern human dispersals after approximately 125 ka.

These results are interesting because they add  evidence for the spread of early hominin and the emergence of quite sophisticated stone technology, this time in India. This is probably the area the predecessors of the Australian Aborigines moved through so many millennia later.

In a second piece, this time in The Conversation, Fossil jawbone from Israel is the oldest modern human found outside Africa, 26 January 2018, Rolf Quam reports on the dating of human fossilised teeth found in the Misliya cave in Israel. The fossil, an upper left jawbone with most of the teeth attached, has been dated to 177,000-194,000 years ago. This is considerably older than any other remains from our own species, Homo sapiens, ever discovered outside of Africa  .

In a paper to be delivered in Israel this week,  John Hawks proposes to reflect on  the deep time of human origins and evolution:

To me, right now, the most critical area where we know the story was complex, and badly need new data and models to understand that complexity, is around 250,000 to 350,000 years ago. 

It was then that our modern human ancestors in Africa began to differentiate from an initially small population into branches that still exist in different regions of Africa today. It is now clear that many other hominin populations existed at the same time, including Homo naledi and some archaic forms of humans in Africa, Neandertals, Denisovans, and possibly other archaic humans in Eurasia, Homo floresiensis in Flores (and maybe others). In Africa, in Europe, and in Asia, some ancient populations experimented with, and ultimately adopted, new stone tool forms.
The big questions of human evolution all now cause us to focus upon this time interval for answers. How did culture influence our evolutionary pathway? How did ancestral hominins become modern humans? How did these hominin populations fit into their environment in ways that enabled them to survive and coexist? 

I don’t have answers to these questions, but I now think that this critical time period is where we must look

I would love to hear those reflections.

So what do we make of all this?

• Around 385 ± 64 thousand years ago we have the emergence of a reasonably sophisticated stone using hominin technology in India
• Around 250,000 to 350,000 years ago we have the emergence of Homo Sapiens in Africa
• Around 177,000-194,000 years ago we appear to have Homo Sapiens in what is now Israel
• Around 65,000 years ago, the Aborigines were in Australia having traveled through Pleistocene Asia, most probably but not certainly via what is now India. 

No doubt the pattern will shift further as we learn more, but it does provide a working approximation for further thought.