Palau Is An Oceania Outlier

This is a further refinement of an already pretty well worked out story of Oceanian origins. 

The ultimate source of Oceanian and Austronesian seafaring people was one of the indigenous tribes of what is now called Taiwan (we have identified which of them it was based upon linguistic evidence), via island Southeast Asia.  

Before expanding very far east, however, these Formosan origin Lapita people admixed with Papuan people (in an encounter that amounted to a hostile conquest).

This "graphical abstract" really sums up a new paper on the topic. 

Note that the dates in this image are "before present", i.e. before 1950 by archeological convention, and not BCE. The initial settlement of Palau was roughly contemporaneous with the Greek "dark ages" after Bronze Age collapse, for example, while the admixture of the people who settled Palau was contemporaneous with the Late Bronze Age in Europe.

An educated layman's explanation of the paper explains: 

About 3200 years ago, Southeast Asian seafarers known as the Lapita pushed east into the tropical islands of the Pacific Ocean, hitting nearly every habitable isle in that corner of the globe from New Guinea to Fiji and Tonga. As they did so, they left behind artifacts of their culture, including pottery stamped with distinctive geometric patterns.

But on Palau, there’s not a single shard of Lapita pottery—and the island’s inhabitants speak a language that’s distinct from the tongues spoken on other Pacific islands. So who were the first Palauans, and where did they come from?

A new study published last week in Cell suggests an answer. Genetic evidence confirms Palau’s first settlers descended from Southeast Asians who had intermingled with the Papuans, Indigenous peoples who settled the island of New Guinea some 50,000 years ago.

“It’s lovely to see a piece of Pacific history—which we’ve traditionally been at a bit of a loss to explain—finally start to come together into a more understandable story,” says Murray Cox, a computational biologist at Massey University of New Zealand who wasn’t involved in the new work.

The discovery builds on previous ancient DNA research into the origins of the Lapita themselves. That work, led by evolutionary biologist David Reich at Harvard University and his colleagues, showed that Lapita were essentially pure Southeast Asians of Taiwanese roots—but that modern populations on Pacific islands showed Papuan ancestry, too. The studies suggested this Papuan ancestry came in about 2500 years ago, as Papuans began to join the same canoe voyages that had earlier carried Lapita settlers into the region.

From Science.

The underlying paper in Cell is as follows:

Highlights

• Ancient DNA of 21 individuals from Palau spans around 2,400 years

• Papuan-East Asian admixture in Palauans predates initial settlement

• Over 2,900 years of genetic continuity in Palau

• Shared East Asian-Papuan admixture in Palau and eastern Indonesia 

Summary 

The first people reached Remote Oceania 3,000 years before present (BP), arriving roughly simultaneously in the southwest Pacific, the Marianas Archipelago, and Palau. However, no genome-wide ancient DNA data have been available from Palau, a gap we address by reporting 21 individuals from four archaeological sites dating between 2,900 and 500 BP. 

All had approximately 60% ancestry related to East Asians and 40% to Papuans, similar to present-day Palauans, the longest stretch of population continuity anywhere in Remote Oceania. The lengths of contiguous Papuan ancestry segments in the oldest individuals show that major admixture between Papuans and East Asians in the ancestors of all sampled Palauans began prior to first settlement. This differs from the pattern in the southwest Pacific, where sampled individuals of the Lapita archaeological culture from three different islands had almost entirely East Asian ancestry, with large amounts of Papuan admixture observed only hundreds of years later. 

Yue-Chen Liu, et al., "Papuan admixture predated the settlement of Palau" (March 10, 2026).

Quick Hits

* The Sumerians had different number words and symbols to count numbers of different kinds of things. So, for example, the word for five pieces of fruit would be different than the word for five logs.

* Egyptian pyramids were built as trapezoids and then cut down to pyramids with the left over rock used to make new pyramids.

* Reputedly, Emperor Basil II of the Byzantine Empire was cruel.

* The Anglo-Saxons kept slaves in the middle ages.

* According to Gerald of Wales ca. 1316 CE, at that time the Irish were predominantly herders.

* Harsh murder sentences for newborns killed or neglected in the throes of unattended child birth are still common today even though the death penalty is almost never sought now in these circumstances.

* The TYRP1 gene variant discovered in 2012, is the cause of blond hair in the Solomon Islands in Melanesia, which is a different gene than the one that causes blond hair in Europeans.

* Before 1480, India and Sri Lanka were nearly connected by a land bridge known as Adam’s Bridge.

* There were once oceans on Mars.

High-resolution orbital images of Mars' largest canyon reveal ancient river deltas, proving the Red Planet once held an ocean the size of Earth's Arctic.

New high-resolution imagery from the European Space Agency’s ExoMars Trace Gas Orbiter has provided the most definitive evidence to date that Mars was once a blue planet. Researchers at the University of Bern identified distinct fan-shaped sediment deposits in the southeast Coprates Chasma region, part of the massive Valles Marineris canyon system. These structures, remarkably similar to river deltas on Earth, all sit at a consistent elevation between 3,650 and 3,750 meters. This geological alignment points to one unmistakable conclusion: the presence of an ancient coastline where rivers once emptied into a vast, stable sea approximately 3.37 billion years ago.

While previous theories about Martian oceans relied on lower-resolution data, this study offers direct geomorphological proof of a shoreline. The findings suggest that a massive body of water, comparable in size to Earth’s Arctic Ocean, once covered the entirety of Mars’ northern hemisphere. Though today these ancient deltas are buried beneath wind-sculpted dust and dunes, their distinctive shapes remain preserved. This discovery drastically alters our view of Martian history; the existence of a planet-wide water cycle and a stable ocean suggests that the conditions necessary for life were not isolated occurrences but a global phenomenon.

Source: Argadestya, P., et al. "Geomorphological and sedimentological evidence of a coastline in Southeast Coprates Chasma." npj Space Exploration (2026).

* There are social octopi that build homes for themselves off the coast of Australia.

* This very little bugger ,who is part of this clade of animals (and more specifically this one) is kind of cute in a Disney monsters way. They are the most heat-tolerant complex animal known to science after tardigrades (or water bears), which are able to survive temperatures over 150 °C. They were discovered in 1980 off the Galapagos islands.

When they grow up, they look like this (the "fur" is a symbiotic species of bacteria):

* A photograph of the February 19, 2026 solar eclipse in Antarctica (not AI).

* Nature can be amazing (also not AI).

* In West Texas, ca. 4500 BCE, hunter-gatherers used non-returnable boomerang sticks for small game and atlatl to throw their carefully crafted spears further for big game.

A cache of ancient weapons, more than 6,000 years old, has been uncovered in a remote rock shelter in West Texas, offering one of the clearest pictures yet of early life in North America.

The discovery was made at the San Esteban rock shelter in the Big Bend region, an area known for its dry climate and rugged desert landscape. That dryness turned out to be a gift to archaeologists. Items that would normally rot away wood, leather bindings, plant fibers remained intact for thousands of years. Inside the shelter, researchers found a carefully stored hunting kit dating to around 4,500 B.C., including wooden spear shafts wrapped in leather, stone projectile points, and parts of atlatls, the spear-throwing tools that dramatically increased a hunter’s range and power.

An atlatl works like a lever, giving a thrown spear greater speed and force. With it, hunters could strike animals from distances that would otherwise be impossible with a simple hand throw. Tests and prior studies show these tools could send projectiles well over 100 feet with deadly accuracy. The craftsmanship seen in the newly uncovered pieces shows careful shaping, balance, and planning. These were not rough survival tools; they were refined hunting systems built by people who deeply understood their environment.

Researchers also identified curved wooden throwing weapons often described as straight or non-returning boomerangs. Unlike the returning boomerangs many people picture today, these were designed to fly straight and hit small game with strong impact. Their presence adds another layer to what appears to have been a well-organized toolkit, likely stored together for repeated use.

The San Esteban site has a long history of human occupation stretching back thousands of years. Findings from this latest excavation reinforce the idea that the Big Bend region was not a temporary stop for wandering groups but a place where people lived, adapted, and developed sophisticated survival strategies. The tools show planning, skill, and an ability to work with available materials in smart, efficient ways.

Archaeologists involved in the project say the discovery helps rewrite outdated ideas about early North American societies. These communities were not primitive in the way older textbooks sometimes suggested. They engineered effective hunting technology, understood animal behavior, and created tools built to last.

As research continues, scientists hope to learn more about how these weapons were used, how they were stored, and what they reveal about daily life 6,000 years ago. For now, the dry rock shelter in West Texas has delivered something rare: a direct, tangible connection to hunters who once stood in the same desert landscape, preparing their tools for the next expedition.

* Maize farmers in Peru’s Chincha Valley were fertilizing their crops with seabird poop as early as the year 1250 CE.

* According to this source:

Around 3,800 years ago, a magnitude-9.5 megaquake struck northern Chile's coast, creating the largest earthquake known in human history. The rupture extended roughly 620 miles along the fault line—longer than the devastating 1960 Valdivia earthquake—and generated tsunamis with waves reaching 66 feet that traveled 5,000 miles across the Pacific Ocean to New Zealand. Archaeologists discovered marine deposits, boulders, shells, and sea life displaced far inland in the Atacama Desert, along with toppled stone structures buried beneath tsunami sediment, all radiocarbon-dated to this single catastrophic event.

The disaster forced complete coastal abandonment. Communities that depended on the ocean for survival relocated inland, staying away from the coast for over 1,000 years—an extraordinary response that demonstrates the quake's devastating impact on human populations. Researchers now recognize this megathrust earthquake, caused when tectonic plates suddenly unlocked after building massive strain, as both the oldest discovered earthquake-tsunami disaster in the Southern Hemisphere and a critical warning for modern coastal populations across the Pacific.

* Every recorded earthquake worldwide, 2015 to 2025 (my source didn't cite a source).

 

Austronesian-Papuan People Replaced The First Modern Humans In Wallacea

Wallacea is the ecological region between the Wallace Line and the Lydekker Line (image via Wikipedia at the link). The plants and animals there differ greatly from those to the west (which were connected by land to mainland Asia when sea levels were lower) because neither animals nor 46,000 years of settlers after the first modern humans to cross into it, could cross the roughly 30 miles of deep sea between the regions.

The most basal modern human populations outside Africa, which also have the greatest Denisovan admixture, are the indigenous people of Papua New Guinea and Australia. People from this wave were also present on the islands of the Wallacean Archipelago in Indonesia and lived there undisturbed for about 46,000 years. 

But, when Papuans made contact with and fused with Austronesian sea farers (who originated on the island that is now called Taiwan) around 3500 years ago, contemporaneously with the late Bronze Age in Europe, the resulting fused population replaced the descendants of the first wave of modern humans in the Wallacean Achipelago.

Significance

We present a comprehensive study of the human genetic history of the Wallacean Archipelago and West Papuan regions of Indonesia, including 254 newly sequenced genomes, mostly from previously undocumented populations. In combination with linguistic and archaeological evidence, we show that Wallacean societies were transformed by the spread of genes and languages from West Papua in the past 3,500 y—the same period that Austronesian seafarers were actively mixing with Wallacean and Papuan groups. These migrant groups have largely replaced local Wallacean ancestry sources, challenging common assumptions that Papuan-related ancestry in Wallacea descends from first human migrants enroute to Sahul >50,000 y ago, and suggesting that these ancient movements may not be readily recoverable from modern genetic data alone.

Abstract

The tropical archipelago of Wallacea was first settled by anatomically modern humans (AMH) by 50 thousand years ago (kya), with descendent populations thought to have remained genetically isolated prior to the arrival of Austronesian seafarers around 3.5 kya. 

Modern Wallaceans exhibit a longitudinal countergradient of Papuan- and Asian-related ancestries widely considered as evidence for mixing between local populations and Austronesian seafarers, though converging multidisciplinary evidence suggests that the Papuan-related component instead comes primarily from back-migrations from New Guinea. 

Here, we reconstruct Wallacean population genetic history using more than 250 newly reported genomes from 12 Wallacean and three West Papuan populations and confirm that the vast majority of Papuan-related ancestry in Wallacea (~75 to 100%) comes from prehistoric migrations originating in New Guinea and only a minor fraction is attributable to the founding AMH settlers. 

Mixing between Papuan and local Wallacean lineages appears to have been confined to the western and central parts of the archipelago and likely occurred contemporaneously with the widespread introduction of genes from Austronesian seafarers—which now comprise between ~40 and 85% of modern Wallacean ancestry—though dating historical admixture events remains challenging due to mixing continuing into the Historical Period. In conjunction with archaeological and linguistic records, our findings point to a dynamic Wallacean population history that was profoundly reshaped by the spread of Papuan genes, languages, and culture in the past 3,500 y.

Gludhug A. Purnomo , Shimona Kealy, Sue O’Connor, Raymond Tobler, et al., "The genetic origins and impacts of historical Papuan migrations into Wallacea" 121 (52) PNAS e2412355121 (December 17, 2024). Hat tip to DDeden.

Archaic Hominins That Were Contemporaneous With Modern Humans

There were at least eight named non-H. sapiens archaic hominin species that existed in time periods overlapping those of  modern humans, H. sapiens, who evolved around 300,000 years ago. All were in the "Old World". There is no credible evidence that archaic hominin ever made it to the Americas, Australia, New Zealand, or most of the other islands of Oceania beyond island southeast Asia.

One was H. erectus that went extinct around 100,000 years ago after more than two million years roaming the Old World, first in Africa and later in Asia. There were also two hobbit-like species in island Southeast Asia, three East Eurasian sister clades to modern humans, the small but not hobbit-like H. naledi in Southern Africa, and Neanderthals in West Eurasia, although some of these species may actually be regional variants of the same species. 

All of these archaic hominin species had gone extinct (with the possible extended duration of a small isolated relict population or two, perhaps H. floresiensis) by about 29,000 years ago, leaving modern humans as the sole survivors (although some modern humans have Neanderthal ancestry (up to about 2%) from admixture events starting around 100,000 years ago, and some modern humans have both Neanderthal and also up to about 6% Denisovan ancestry, although absolute percentages are harder to estimate than percentages relative to other individuals with the same kind of introgression) from admixture events around the time that modern humans reached Southeast Asia. Incidentally, the introgression went both ways, with Neanderthals having up to 6% modern human introgressed ancestry, possibly due to events as much as 250,000 years ago. These sister clades capable of producing hybrid offspring may have been regionally specialized into climate niches.

Notably the remains of the Red Deer Cave People of China from 14,000 years ago (a few thousand years before the start of the Holocene era) are genetically modern humans and are not archaic hominins despite some of their seemingly archaic features. See also here.

I am also inclined to think that they may yet be a small relict population of small archaic hominins in a remote Indonesian jungle on the island of Sumatra and perhaps Flores as well, where these cryptids, called Orang Pendek, locally, have been attested but not definitively confirmed to still exist. I discuss this further at this post.

Homo floresiensis (discovered in 2003) are commonly known as "hobbits" and have been found on the island of Flores. Their phylogeny is disputed, but I find the theory that they are an asian branch of H. habilis to be most convincing. H. luzonesis (discovered in 2007) is similar and contemporaneous, but found further east in the Philippines and is supported by a less complete archaeological record. Both of these diminutive species are found in association with late Pleistocene tools and "oriental fauna".

Personally, being more of a lumper than a splitter, I'm inclined to see H. floresiensis and H. luzonesis as sub-species variations of the same species ("race" within that species to use some outdated terminology), and likewise to see H. longi, H. juluensis, and Denisovans as sub-species variations of the Denisovan species. The Hualongdong archaic hominin fossils, might be another hybrid individual or could be a hybrid individual, perhaps a Neanderthal-Denisovan hybrid individual (something that has precedent in a Denisovan cave DNA sample). 

Academic anthropologists, in contrast, tend to be splitters, in part, because it is cool and career advancing to discover and name your own archaic species, in part because the data is so fragmentary that grouping different fragmentary remains in a clade presumes relationships between the remains that aren't solidly proven, and in part, because it is easy to underestimate how much morphological diversity is possible within a single species if populations of it exposed to different environmental conditions.

H. longi a.ka. "dragon man" dates to an earlier time period (still contemporaneous with modern humans in Africa) in China and Manchuria, was discovered in 1933, and has been hypothesized to be a sister clade to Neanderthals, Denisovans, and modern humans, and a descendant of the pre-modern human hominin species H. antecessor due in part to basal archaic features in the skull. 

H. juluensis (literally "big heads") is contemporaneous H. longi, and beyond that time frame into the time frame of H. floresiensis and was discovered from 1976-1979 in China and Tibet. The authors assign this specimen along with Xiahe and Penghu fossils, to the Denisovan species (a sister clade to Neanderthals and modern humans) based upon comparisons of their fossil teeth and rough geographic proximity. H. juluensis is found in association with early Paleolithic tools and remains of Paleoarctic fauna. But they have larger brain cases than H. longi. A previous suggestions of the link between H. longi and the Denisovan species are discussed here and here at this blog. At least one Denisovan tooth has been found in Laos dated to 131,000 years ago.

The article also discusses the Hualongdong archaic hominin fossils that "date to the late Middle Pleistocene (~300,000 years BP) and display a mosaic of characteristics that cannot be easily fitted into any one lineage," although they are closer to H. longi and H. juluensis. This individual could be a hybrid between these two subspecies, with H. erectus, or with a Neanderthal who was far east of his usual range.

Prior to 2021, H. longi and H. juluensis tended to be classified as H. erectus (remains of which start to appear at a much greater time depth in Asia) or as archaic modern humans.

The Narmada and Maba partial skulls, especially the latter, are suggestively associated with Neanderthals by the article.

These Asian archaic species also overlap in time with the Southern African archaic hominin clade H. naledi which is a sister clade to the modern human ancestors and to the common ancestor of modern humans, Neanderthals, and Denisovans, but is not actually among our ancestors. As I explained at the link, this species "is basically a story from The Silmarillion of hominin evolution. It is entertaining, especially for hard core human evolution fans, but it doesn't really advance the plot."

A small number of papers reported genetic evidence in modern Africans of admixture with an archaic hominin "ghost species" in Africa, but subsequent papers have explained this "ghost species" signal as a methodological artifact that merely arises from population structure in early modern human Africans (see also here). But there may have been relict archaic hominins that did not admix with modern humans in Africa that were also contemporaneous with modern humans, at least, early on.

The question of whether behaviorally modern humans started showing advanced behavior around 70,000-50,000 years ago (at the dawn of the Upper Paleolithic era and close in time to the Out of Africa event for modern humans), was associated with an evolutionary leap in their brains is an open and unresolved question. See also here (addressing the question of what made modern humans genetically distinct from archaic hominins).

A greater degree of Late Quaternary hominin morphological variability is present in eastern Asia than previously assumed. Indeed, a number of distinct populations are present, some that now have new specific names: Homo floresiensis; H. luzonensis; H. longi; H. juluensis. With this piece, we describe the various groupings based on the current hominin fossil record of eastern Asia.

Christopher J. Bae & Xiujie Wu, "Making sense of eastern Asian Late Quaternary hominin variability" 15 Nature Communications 9479 (November 2, 2024) (opoen access) (hat tip to neo).

Papuan Demographic History From Modern Genomes

A new pre-print at bioRxiv disputes the status of Papuans (presumably together with aboriginal Australians) as an outgroup to both European and Asian populations. Instead, it positions them as a sister population of other Asian populations.

The demographic history of the Papua New Guinean population is a subject of significant interest due to its early settlement in New Guinea, at least 50 thousand years ago, and its relative isolation compared to other out of Africa populations. This isolation, combined with substantial Denisovan ancestry, contributes to the unique genetic makeup of the Papua New Guinean population. Previous research suggested the possibility of admixture with an early diverged modern human population, but the extent of this contribution remains debated. 

This study re-examines the demographic history of the Papua New Guinean population using newly published samples and advanced analytical methods. Our findings demonstrate that the observed shifts in relative cross coalescent rate curves are unlikely to result from technical artefacts or contributions from an earlier out of Africa population. Instead, they are likely due to a significant bottleneck and slower population growth rate within the Papua New Guinean population. Our analysis positions the Papua New Guinean population as a sister group to other Asian populations, challenging the notion of Papua New Guinean as an outgroup to both European and Asian populations. 

This study provides new insights into the complex demographic history of the Papua New Guinean population and underscores the importance of considering population-specific demographic events in interpreting relative cross coalescent rate curves.

Mayukh Mondal, et al., "Resolving out of Africa event for Papua New Guinean population using neural network" bioRxiv (September 23, 2024) https://doi.org/10.1101/2024.09.19.613861

The introduction to the paper explains that:

The Papua New Guinean (PNG) population is among the most fascinating in the world, owing to its unique demographic history. Following the Out Of Africa (OOA) event, modern humans populated New Guinea at a remarkably early date-at least 50 thousand years ago. Since then, the population has remained relatively isolated compared to other OOA populations (such as European and Asian populations) and has gone through a strong bottleneck. The substantial Denisovan ancestry within the PNG population and the strong correlation between Denisovan and Papuan ancestries, contribute to the genetic distinctiveness of the PNG population. 

Researchers have suggested that the genomes of PNG populations contain evidence of admixture with a modern human population that might have diverged from African populations- around 120 thousand years ago- much earlier than the proclaimed primary divergence between African and OOA populations. However, the extent to which this early diverged population contributed to the genome of PNG populations remains a subject of ongoing debate. Interestingly, this early migration hypothesis is more widely accepted by archeologists. 

Pagani et al supports this hypothesis, notably through Relative Cross-Coalescent Rate (RCCR) analysis. This RCCR analysis suggests that the PNG population diverged from African populations significantly earlier than other OOA populations. They argued that this earlier divergence indicated by the RCCR curve might reflect a contribution from an earlier OOA population specific to PNG. While this shift in the RCCR curve is well-documented, some researchers attribute it to technical artefacts such as low sample sizes and phasing errors rather than genuine demographic events. 

The origins of the primary lineage of the PNG population have also been contested. Some researchers propose that the PNG population is closely related to the Asia-Pacific populations and serves as a sister group to other Asian populations. Conversely, other researchers argue that the PNG population is an outgroup to both European and Asian populations. 

Recent advancements in analytical methods may provide new insights into these debates. For example, Approximate Bayesian Computation with Deep learning and sequential Monte Carlo (ABC-DLS) allows for the use of any summary statistics derived from simulations to train neural networks, which can then predict the most likely demographic models and parameters based on empirical data. Additionally, the Relate software enhances RCCR analysis by employing a modified version of the hidden Markov model, initially used in the Multiple Sequentially Markovian Coalescent (MSMC) method, allowing for the analysis of thousands of individuals with greater robustness. 

In this paper, we re-examine the demographic history of the PNG population using newly published samples combined with data from the 1000 Genome Project and cutting edge methods. This approach has enabled us to address these longstanding questions with greater precision. We first generate new empirical RCCR curves and demonstrate that the previously observed shift is unlikely to be the result of low sample size or phasing errors. Through simulations, we further show that the PNG population is indeed a sister group to other Asian populations and this shift is probably not due to contributions from an earlier OOA population. Instead, it is likely a consequence of a significant bottleneck and slower population growth in the PNG population.

The paper then defines the demographic models that the paper analyzed at a broad brush level:

To explore the demographic processes causing the observed RCCR shift, we tested five plausible demographic scenarios labelled A, O, M, AX and OX. In Model A, the PNG and East Asian populations are sister groups. Model O positions the PNG population as an outgroup to both European and East Asian populations. Model M combines elements of both A and O, suggesting that the PNG population arose from admixture between a sister group of the Asian population and an outgroup of European and Asian populations. Model AX postulates that the PNG population is a sister group to the Asian population but received input from an earlier OOA population. Finally, in Model OX, the PNG population receives a contribution from an earlier OOA population, while remaining ancestry came from an out group to the European and East Asian populations. . . .  

The best-fitting parameters for Model A largely correspond with the previously established OOA model, with some deviations specific to the inclusion of the PNG population. 

Our model suggests that all OOA populations, including PNG, diverged from African populations (represented by Yoruba) around 62.4 (62- 62.8) thousand years ago, experiencing a significant bottleneck. Approximately 52 (51.6- 52.8) thousand years ago, Neanderthals contributed around 3.7% (3.59- 3.85%) of the genome to these OOA populations. Shortly thereafter, Europeans and East Asians diverged from the PNG populations around 51.2 (50.8- 51.6) and 46.2 (45.9- 46.5) thousand years ago, respectively. The PNG population then mixed with Denisovans around 31.2 (31.1- 31.5) thousand years ago, contributing approximately 3.16% (3.05- 3.21%) to the genome of PNG. 

Our analysis also shows that the PNG population experienced a more severe bottleneck (674 [663- 689] of effective population size) than other OOA populations (i.e. Europeans 3512 [3423- 3589] and East Asians 1771 [1730- 1799] of effective population size), with growth rates significantly lower than those of other OOA populations, consistent with previously published data. 

While our parameter inference is generally robust within the individual model, substantial changes occur when the underlying model is altered. Given that determining the precise demographic model for human populations is an ongoing effort, parameter estimates should be considered supplementary to the model rather than independent results. 

The concluding discussion of the results notes that:

We successfully replicated the shift observed by Pagani et al., confirming its presence in both physically mapped and statistically phased sequences, which involved over 100 PNG samples. This consistency suggests that the shift is reproducible, though its underlying cause may differ from the original interpretation of Pagani et al.. 

Our analysis using ABC-DLS supports a simpler demographic model for PNG populations, proposing them as a sister group to Asians with no substantial detectable contribution from an earlier OOA population. Interestingly, our simulated models reveal that a stronger bottleneck with a lower growth rate could produce a similar shift in RCCR analysis and potentially be misinterpreted as a signal of an earlier population separation. While RCCR is a valuable proxy for estimating the separation time between populations, it is not without biases. The shift could result from various factors, including earlier divergence times, admixture with earlier diverged populations, or even a bottleneck in one of the populations, as demonstrated in our study. Interestingly this demographic history of stronger bottleneck with slower growth rate was also experienced by the Andamanese population, which explains the shift found in the Andamanese population as well. Thus, using RCCR analysis to rebuild the tree of divergence might need to be revised.

The observed shift in the RCCR curve suggests that a recent bottleneck can impact estimates of effective population size in the distant past. Notably, in our simulations, the Papua New Guinean bottleneck occurred much later (around 46.2 thousand years ago) than the observed shift (peaking around 100 thousand years ago) with a population (Yoruba) that separated a long time ago. This finding implies that the estimation of effective population size and cross-coalescent rates may not be entirely independent, potentially affecting RCCR analysis in its current form. Further analysis suggests that the estimation of coalescent rate was affected earlier than true changes of effective population size, which shifts the RCCR curve as RCCR is a ratio of coalescent rates. Additionally, this shift was absent in simulations involving populations that separated 300 thousand years ago, akin to the San population, indicating that the bottleneck effect diminishes over longer separation times.

Our results also reveal that when the contribution from an earlier OOA population is between 1-5%, our neural analysis misclassifies the Model AX to be Model A at a higher rate. We found that when the contribution from an earlier OOA population is set between 1-5%, our ABC-DLS analysis tends to misclassify the Model AX as Model A at a higher rate. A similar issue arises with Model M, where a low contribution (less than 5%) from an outgroup Eurasian population can still be misclassified as Model A. Thus our analysis does not work for less than 5% contribution from these unknown ghost populations, though Model OX does not show a similar phenomenon with Model A misclassification. While we cannot completely rule out the possibility of a small contribution from these populations, our analysis suggests that such models are not necessary to explain the RCCR shift as previously proposed.

Interestingly, our results position PNG as a sister group to Asian populations rather than an outgroup of European and Asian. The primary difference between those models and ours lies in the migration rates between populations. Previous models that incorporated significant migration rates between populations were found to have confounded results, leading us to avoid including migration rates in our models. Without migration, our Model O closely resembles the previous models of PNG. Given that those models used substantial migration rates, they are not directly comparable to our models without migration rate. Indeed with high migration rates, our approach failed to distinguish between Model A and O with high certainty. Still our work suggests that the main lineage of PNG is coming from a sister group of Asia, which was not confounded by a convoluted migration rate patterns between populations.

Our parameter estimation suggests that the PNG population separated from other populations around 46.2 (45.9 - 46.5) thousand years ago, a timeline that aligns with archaeological estimates of when the ancestors of PNG reached the ancient continent of Sahul, the landmass that once connected New Guinea and Australia. 

Additionally, our Relate analysis indicates that the separation time between PNG and European populations was the longest observed among OOA populations. However, as our model suggests, this is likely a bias caused by the bottleneck of PNG. This bottleneck may lead to an overestimation of the separation time, particularly in RCCR analysis. In reality, it is more likely that PNG and East Asian populations separated later than the divergence between PNG and European populations. 

In conclusion, our study provides compelling evidence that the unique demographic events—specifically, a significant bottleneck and slower population growth—within the PNG population are key factors influencing the observed shifts in RCCR curves. These findings not only refine our understanding of PNG's demographic history but also emphasise the necessity of accounting for population-specific demographic events when interpreting RCCR curves. 

Pre-Colombian New World Admixture In Ancient Easter Island Genomes

Polynesian people reached Easter Island around 1250 CE and were the first humans there. Europeans first reached the island in 1722 CE, at which time there were 1,500 to 3,000 people living there. European diseases, Europeans killing them, and Portuguese slave traders brought the Polynesian population down to a low point of 110 people some time after the 1860s. This paper's introduction suggested that as many as 15,000 people were living on the island on its pre-European peak, but later studies and this paper suggest that this peak population was greatly overestimated. The best fit to the genetic data shows a steady but slow population increase on the island after it was settled until European first contact, and the ecological collapse theory is rejected.

About 10% of Easter Island ancestry comes from pre-Columbian admixture with the indigenous peoples of the Americas as a result of admixture events in the time period from 1250-1430 CE, with a best fit timing in the late 1300s. This date also strongly favors admixture with indigenous Americans after, and not before the ancestors for the sampled individuals arrived on Easter Island. In particular, "the Native American component in Ancient Rapanui to be most closely related to Pacific Coast South Americans and not North Americans or populations east of the Andes further substantiates trans-Pacific contacts between Polynesians and Native Americans."

This further corroborates prior evidence of pre-Columbian contact between Polynesians and the pre-Columbian peoples of the Americas, and is also consistent the with expected time frame of these contacts from prior data.

we reconstructed the genomic history of the Rapanui on the basis of 15 ancient Rapanui individuals that we radiocarbon dated (1670–1950 CE) and whole-genome sequenced (0.4–25.6×). We find that these individuals are Polynesian in origin and most closely related to present-day Rapanui, a finding that will contribute to repatriation efforts. Through effective population size reconstructions and extensive population genetics simulations, we reject a scenario involving a severe population bottleneck during the 1600s, as proposed by the ecocide theory. Furthermore, the ancient and present-day Rapanui carry similar proportions of Native American admixture (about 10%). Using a Bayesian approach integrating genetic and radiocarbon dates, we estimate that this admixture event occurred about 1250–1430 CE.

From here. The body text of the article provides some background:

several pieces of evidence suggest that Rapa Nui did not constitute the easternmost point of long sea voyages and that Polynesian peoples eventually reached the Americas before Columbus. 

Genetic studies on present-day individuals have supported such contact. Present-day Rapanui were found to harbour Native American and European admixture in their genomes. Notably, in that work, Native American admixture (dated 1280–1495 CE) was estimated to pre-date European admixture (dated 1850–1895 CE). 

More recently, Native American admixture was detected not only in present-day individuals from Rapa Nui, but also from Rapa Iti, Tahiti, Palliser, Nuku Hiva (North Marquesas), Fatu Hiva (South Marquesas) and Mangareva. In that study, the Native American gene flow in the different islanders was dated between 1150 (South Marquesas) and 1380 CE (Rapa Nui), in line with the date estimated in ref. 5. 

However, the only two ancient DNA studies of ancient Rapanui so far did not find evidence for Native American admixture. The first study focused on mitochondrial DNA from 12 individuals, whereas the second analysed low-depth (0.0004–0.0041×) whole-genome data from 5 individuals dating before and after European contact. In the latter, downstream population genetic analyses confirmed that the five ancient individuals were Polynesian. However, even though the analysed human remains were post-dating the inferred Native American admixture time, no Native American ancestry was reported in these ancient genomes, casting doubt on the findings based on data from present-day populations.

The admixture and Native American contract dates cited above are also just in the right time frame to explain the geographic distribution and lack of fixation of "Paleo-Asian" ancestry in modern South American populations, although that scarce Paleo-Asian component is very small and is seemingly not a very close match to Polynesian ancestry. 

The geographic spread and lack of fixation of the Paleo-Asian component in South America is inconsistent and irreconcilable with a time depth greater than that of the primary founding population of the Americas for that genetic ancestry component.

Easter Island May Have Independently Developed A Written Script

The people of Easter Island may have independently developed their own written script in a language that is now lost. The script is undeciphered.

A tablet of wood inscribed with the undeciphered "rongorongo" script from the Eastern Pacific island Rapa Nui, also called Easter Island, predates the arrival of Europeans there, strengthening the likelihood that the script is one of the few independently invented writing systems. The wood from one of four rongorongo tablets preserved in a collection in Rome dates to between 1493 and 1509 — more than 200 years before the first recorded arrival of Europeans on the island in the 1720s[.] . . . the results support the idea that rongorongo was an original invention by the Rapa Nui islanders rather than being influenced by the writing they'd seen used by Europeans.

Rapa Nui, which sits nearly 2,400 miles (3,800 kilometers) off the coast of Chile, was settled by humans between 1150 and 1280. Although Europeans arrived in the 18th century, they didn't notice the local glyph-based script until 1864, which now exists on only 27 wooden objects, none of which are still on the island. Catholic missionaries took four of these tablets in 1869 and sent them to the bishop of Tahiti, who later sent them to Europe.

Ferrara and her colleagues conducted radiocarbon dating on tiny samples of the four rongorongo tablets held by a congregation of Catholic nuns based in Rome. The radiocarbon dates suggested that three of the tablets were made from trees felled in the 18th or 19th centuries, but the radiocarbon date of a fourth indicated it came from a tree felled in the 15th century, Ferrara said. That predates the arrival of Europeans on Rapa Nui and suggests that the rongorongo script was in use before then, she said.

(Image credit: INSCRIBE and RESOLUTION ERC Teams) 

In this case, however, the inscription was probably made about the time the wood was obtained, because the alternative explanation — that the wood had been stored for more than 200 years before it was used — seems unlikely, she said. The new analysis also suggested the wood from the oldest tablet came from a tree species not native to Rapa Nui, and the researchers think it was probably a piece of driftwood.

Rapa Nui is famous for its many archaeological mysteries, including the giant stone heads known as moai, and many people have tried — without success — to decipher the rongorongo script.

Ferrara said more than 400 different rongorongo glyphs have been recognized among the roughly 15,000 surviving characters, and none correspond to any other known system of writing.

Rafal Wieczorek, a chemist at the University of Warsaw who was not involved in the latest study but has investigated other rongorongo tablets, said that while the new research isn't conclusive, it is a strong indication that the script was an independent invention — perhaps one of only a handful of times when a writing system had been invented from scratch, without knowledge of other writing systems. . . . "I actually believe that rongorongo is one of the very few independent inventions of writing in human history, like the writing of the Sumerians, the Egyptians and the Chinese," he said. "But belief is a different thing than hard data … so ideally, we would like to test all the tablets."

From Live Science.

Given that only sample on "old wood" was driftwood anyway, the possibility that the script is not as ancient as the date of the wood suggests is less of a stretch than it might seem. It wouldn't have to have been stored for 200 years. It would be enough for it to have lingered where it originally fell for decades and then for it to have drifted to Easter Island much later.

The fact that the script didn't spread elsewhere in Polynesia when it was known to have some level of trade with it is also a challenge to the notion that the script was developed independently in the late 15th or early 16th centuries.

But, the age of the wood makes it at least possible that the script predates European contact, and the lack of any connection to other known scripts is also an important factor favoring its status as an independent script.

Wikipedia covers it at length here. It notes that: "some calendrical and what might prove to be genealogical information has been identified, none of these glyphs can actually be read. . . . Oral history suggests that only a small elite was ever literate and that the tablets were sacred." It states that the conventional view is that this is a proto-language mnemonic device, which students wrote on fragile banana leaves, rather than a true language. Unlike other proto-linguistic scripts, like the Harappan script (of the Indus River Valley) and Vinca script (of the Balkans), and early hieroglyphs, however, this one does not appear to have had a primarily economic purpose.

The paper and its abstract are as follows:

Placing the origin of an undeciphered script in time is crucial to understanding the invention of writing in human history. Rapa Nui, also known as Easter Island, developed a script, now engraved on fewer than 30 wooden objects, which is still undeciphered. Its origins are also obscure. Central to this issue is whether the script was invented before European travelers reached the island in the eighteenth century AD. Hence direct radiocarbon dating of the wood plays a fundamental role. Until now, only two tablets were directly dated, placing them in the nineteenth c. AD, which does not solve the question of independent invention. Here we radiocarbon-dated four Rongorongo tablets preserved in Rome, Italy. One specimen yielded a unique and secure mid-fifteenth c. date, while the others fall within the nineteenth c. AD. Our results suggest that the use of the script could be placed to a horizon that predates the arrival of external influence.

Ferrara, S., Tassoni, L., Kromer, B. et al. "The invention of writing on Rapa Nui (Easter Island). New radiocarbon dates on the Rongorongo script." 14 Sci Rep 2794 (Feb. 2, 2024) (open access) https://doi.org/10.1038/s41598-024-53063-7

The Easter Island Statues Have Bodies

Via this news story (which has many more photos of Easter Island statue bodies).

The fact that the Easter Island (a.k.a. Rapa Nui) statues (which are known as "moai" from the Spanish word for statue) have bodies is old news. 

But the statues shown with their full bodies are still striking to actually see, and are a nice image to brighten your day. Why these statutes ended up getting so deeply buried also appears to be a still open question in anthropology.

What are they?

Moai or moʻai (/ˈmoʊ.aɪ/ (listen) MOH-eye; Spanish: moái; Rapa Nui: moʻai, lit. 'statue') are monolithic human figures carved by the Rapa Nui people on Rapa Nui (Easter Island) in eastern Polynesia between the years 1250 and 1500. Nearly half are still at Rano Raraku, the main moai quarry, but hundreds were transported from there and set on stone platforms called ahu around the island's perimeter. 

Almost all moai have overly large heads, which comprise three-eighths the size of the whole statue and they have no legs. The moai are chiefly the living faces (aringa ora) of deified ancestors (aringa ora ata tepuna). The statues still gazed inland across their clan lands when Europeans first visited the island in 1722, but all of them had fallen by the latter part of the 19th century. The moai were toppled in the late 18th and early 19th centuries, possibly as a result of European contact or internecine tribal wars. . . .

Though moai are whole-body statues, they are often referred to as "Easter Island heads" in some popular literature. This is partly because of the disproportionate size of most moai heads, and partly because many of the iconic images for the island showing upright moai are the statues on the slopes of Rano Raraku, many of which are buried to their shoulders. Some of the "heads" at Rano Raraku have been excavated and their bodies seen, and observed to have markings that had been protected from erosion by their burial.

The average height of the moai is about 4 m (13 ft), with the average width at the base around 1.6 m (5.2 ft). These massive creations usually weigh around 12.5 tonnes (13.8 tons) each. . . . 

It is thought that the moai with carved eye sockets were probably allocated to the ahu and ceremonial sites, suggesting that a selective Rapa Nui hierarchy was attributed to the moai design until its demise with the advent of the religion revolving around the tangata manu. 

. . .

Archaeologists believe that the statues were a representation of the ancient Polynesians' ancestors. The moai statues face away from the ocean and towards the villages as if to watch over the people. The exception is the seven Ahu Akivi which face out to sea to help travelers find the island. There is a legend that says there were seven men who waited for their king to arrive. A study in 2019 concluded that ancient people believed that quarrying of the moai might be related to improving soil fertility and thereby critical food supplies.

. . .

Those moai that are less eroded typically have designs carved on their backs and posteriors. The Routledge expedition of 1914 established a cultural link between these designs and the island's traditional tattooing, which had been repressed by missionaries a half-century earlier. . . .

The statues were carved by the Polynesian colonizers of the island, mostly between 1250 and 1500 [CE]. In addition to representing deceased ancestors, the moai, once they were erected on ahu, may also have been regarded as the embodiment of powerful living or former chiefs and important lineage status symbols. Each moai presented a status: "The larger the statue placed upon an ahu, the more mana the chief who commissioned it had." The competition for grandest statue was ever prevalent in the culture of the Easter Islanders. The proof stems from the varying sizes of moai.

Completed statues were moved to ahu mostly on the coast, then erected, sometimes with pukao, red stone cylinders, on their heads. Moai must have been extremely expensive to craft and transport; not only would the actual carving of each statue require effort and resources, but the finished product was then hauled to its final location and erected.

The quarries in Rano Raraku appear to have been abandoned abruptly, with a litter of stone tools and many completed moai outside the quarry awaiting transport and almost as many incomplete statues still in situ as were installed on ahu. In the nineteenth century, this led to conjecture that the island was the remnant of a sunken continent and that most completed moai were under the sea. That idea has long been debunked, and now it is understood that: 

• Some statues were rock carvings and never intended to be completed. 
• Some were incomplete because, when inclusions were encountered, the carvers would abandon a partial statue and start a new one. Tuff is a soft rock with occasional lumps of much harder rock included in it.
• Some completed statues at Rano Raraku were placed there permanently and not parked temporarily awaiting removal.
• Some were indeed incomplete when the statue-building era came to an end.

. . .

Since the island was largely treeless by the time the Europeans first visited, the movement of the statues was a mystery for a long time; pollen analysis has now established that the island was almost totally forested until 1200 CE. The tree pollen disappeared from the record by 1650. 

. . . 

Originally, Easter Islanders had a paramount chief or single leader. Through the years the power levels veered from sole chiefs to a warrior class known as matatoʻa. The therianthropic figure of a half bird and half-man was the symbol of the matatoʻa; the distinct character connected the sacred site of Orongo. The new cult prompted battles of tribes over worship of ancestry. Creating the moai was one way the islanders would honor their ancestors; during the height of the birdman cult there is evidence which suggests that the construction of moai stopped.

A Detailed Prehistory Of Micronesia

A new study provides a maximally detailed five wave model of the prehistoric human settlement of Micronesia, relying on ancient and modern DNA, linguistics and archaeology.

Notably, it determines that the Mariana Islands lack Papuan ancestry, and that Micronesians were strictly matrilocal.

Micronesia began to be peopled earlier than other parts of Remote Oceania, but the origins of its inhabitants remain unclear. We generated genome-wide data from 164 ancient and 112 modern individuals. 

Analysis reveals five migratory streams into Micronesia. Three are East Asian related, one is Polynesian, and a fifth is a Papuan source related to mainland New Guineans that is different from the New Britain–related Papuan source for southwest Pacific populations but is similarly derived from male migrants ~2500 to 2000 years ago. 

People of the Mariana Archipelago may derive all of their precolonial ancestry from East Asian sources, making them the only Remote Oceanians without Papuan ancestry. 

Female-inherited mitochondrial DNA was highly differentiated across early Remote Oceanian communities but homogeneous within, implying matrilocal practices whereby women almost never raised their children in communities different from the ones in which they grew up.

Yue-Chen Liu, et al., "Ancient DNA reveals five streams of migration into Micronesia and matrilocality in early Pacific seafarers" 377 (6601) Science 72-79 (June 30, 2022).

The Origins Of Domesticated Chickens

Chickens were domesticated much later than I expected and spread to various places outside Southeast Asia much later than I would have expected (particularly given that a leading Harappan city in the Indus River basin was called "Chicken City" and the fact that they seemed to be part of the Austronesian domesticates package at some point).

For what it is worth, while the positive evidence they cite for the presence of domesticated chickens in various places is solid, the case that they make that earlier evidence, particularly from South Asia and island Southeast Asia, is not credible, is quite conservative and should be taken with a grain of salt.

Though chickens are the most numerous and ubiquitous domestic bird, their origins, the circumstances of their initial association with people, and the routes along which they dispersed across the world remain controversial. In order to establish a robust spatial and temporal framework for their origins and dispersal, we assessed archaeological occurrences and the domestic status of chickens from ∼600 sites in 89 countries by combining zoogeographic, morphological, osteometric, stratigraphic, contextual, iconographic, and textual data. 

Our results suggest that the first unambiguous domestic chicken bones are found at Neolithic Ban Non Wat in central Thailand dated to ∼1650 to 1250 BCE, and that chickens were not domesticated in the Indian Subcontinent. 

Chickens did not arrive in Central China, South Asia, or Mesopotamia until the late second millennium BCE, and in Ethiopia and Mediterranean Europe by ∼800 BCE. 

To investigate the circumstances of their initial domestication, we correlated the temporal spread of rice and millet cultivation with the first appearance of chickens within the range of red junglefowl species. Our results suggest that agricultural practices focused on the production and storage of cereal staples served to draw arboreal red junglefowl into the human niche. Thus, the arrival of rice agriculture may have first facilitated the initiation of the chicken domestication process, and then, following their integration within human communities, allowed for their dispersal across the globe.

Joris Peters, et al., "The biocultural origins and dispersal of domestic chickens" 119 (24) PNAS e2121978119 (June 6, 2022) (open access).