The first whole-genome analyses of ancient human DNA from Southeast Asia reveal that there were at least three major waves of human migration into the region over the last 50,000 years. The research, published online May 17 in Science, complements what is known from archaeological, historical and linguistic studies of Southeast Asia, defined as the area east of India and south of China. The work illuminates another critical portion of the story of ancient population dynamics around the world, joining numerous ancient-DNA studies of Europe as well as burgeoning research from the Near East, Central Asia, Pacific Islands and Africa. "A very important part of the world is now accessible for ancient DNA analysis," said Mark Lipson, a postdoctoral fellow in the lab of ancient-DNA specialist David Reich at Harvard Medical School and first author of the study. "It opens a window into the genetic origins of the people who lived there in the past and those who live there now." An international team led by researchers at HMS and the University of Vienna extracted and analyzed DNA from the remains of 18 people who lived between about 4,100 and 1,700 years ago in what are now Vietnam, Thailand, Myanmar and Cambodia. The team found that the first migration took place about 45,000 years ago, bringing in people who became hunter-gatherers. Then, during the Neolithic Period, around 4,500 years ago, there was a large-scale influx of people from China who introduced farming practices to Southeast Asia and mixed with the local hunter-gatherers. People today with this ancestry mix tend to speak Austroasiatic languages, leading the researchers to propose that the farmers who came from the north were early Austroasiatic speakers. "This study reveals a complex interplay between archaeology, genetics and language, which is critical for understanding the history of Southeast Asian populations," said co-senior author Ron Pinhasi of the University of Vienna. The research revealed that subsequent waves of migration during the Bronze Age, again from China, arrived in Myanmar by about 3,000 years ago, in Vietnam by 2,000 years ago and in Thailand within the last 1,000 years. These movements introduced ancestry types that are today associated with speakers of different languages. The identification of three ancestral populations -- hunter-gatherers, first farmers and Bronze Age migrants -- echoes a pattern first uncovered in ancient DNA studies of Europeans, but with at least one major difference: Much of the ancestral diversity in Europe has faded over time as populations mingled, while Southeast Asian populations have retained far more variation. "People who are nearly direct descendants of each of the three source populations are still living in the region today, including people with significant hunter-gatherer ancestry who live in Thailand, Malaysia, the Philippines and the Andaman Islands," said Reich, professor of genetics at HMS and co-senior author of the study. "Whereas in Europe, no one living today has more than a small fraction of ancestry from the European hunter-gatherers." Reich hypothesizes that the high diversity of Southeast Asia today can be partly explained by the fact that farmers arrived much more recently than in Europe -- around 4,500 years ago compared with 8,000 years ago -- leaving less time for populations to mix and genetic variation to even out. The new findings make it clear that the multiple waves of migration, each of which occurred during a key transition period of Southeast Asian history, shaped the genetics of the region to a remarkable extent. "The major population turnover that came with the arrival of farmers is unsurprising, but the magnitudes of replacement during the Bronze Age are much higher than many people would have guessed," said Reich. Also unexpected were the linguistic implications raised by analyses of the ancestry of people in western Indonesia. "The evidence suggests that the first farmers of western Indonesia spoke Austroasiatic languages rather than the Austronesian languages spoken there today," Reich added. "Thus, Austronesian languages were probably later arrivals." Additional samples from western Indonesia before and after 4,000 years ago should settle the question, Reich said.

Chemical signatures in shale, the Earth's most common sedimentary rock, point to a rapid rise of land above the ocean 2.4 billion years ago that possibly triggered dramatic changes in climate and life. In a study published in the May 24 issue of the journal Nature, researchers report that shale sampled from around the world contains archival quality evidence of almost imperceptible traces of rainwater that caused weathering of land from as old as 3.5 billion years ago. Notable changes in the ratios of oxygen 17 and 18 with more common oxygen 16, said lead author Ilya Bindeman, a geologist at the University of Oregon, allowed researchers to read the chemical history in the rocks. In doing so, they established when newly surfaced crust was exposed to weathering by chemical and physical processes, and, more broadly, when the modern hydrologic process of moisture distillation during transport over large continents started. The evidence is from analyses of three oxygen isotopes, particularly the rare but stable oxygen 17, in 278 shale samples drawn from outcrops and drill holes from every continent and spanning 3.7 billion years of Earth's history. The analyses were done in Bindeman's Stable Isotope Laboratory. Based on his own previous modeling and other studies, Bindeman said, total landmass on the planet 2.4 billion years ago may have reached about two-thirds of what is observed today. However, the emergence of the new land happened abruptly, in parallel with large-scale changes in mantle dynamics. Isotopic changes recorded in the shale samples at that time also coincides with the hypothesized timing of land collisions that formed Earth's first supercontinent, Kenorland, and high-mountain ranges and plateaus. "Crust needs to be thick to stick out of water," Bindeman said. "The thickness depends on its amount and also on thermal regulation and the viscosity of the mantle. When the Earth was hot and the mantle was soft, large, tall mountains could not be supported. Our data indicate that this changed exponentially 2.4 billion years ago. The cooler mantle was able to support large swaths of land above sea level." Temperatures on the surface when the new land emerged from the sea would have likely been hotter than today by several tens of degrees, he said. The study found a stepwise change in triple-isotopes of oxygen around that time frame. That, the scientists said, resolves previous arguments for a gradual or stepwise emergence of land between 1.1 and 3.5 billion years ago. At 2.4 billion years ago, Bindeman said, the newly emerged land began to consume carbon dioxide from the atmosphere amid chemical weathering. The timing also coincides with the transition from the Archean Eon, when simple prokaryotic life forms, archaea and bacteria, thrived in water, to the Proterozoic Eon, when eukaryotes, such as algae, plants and fungi, emerged. "In this study, we looked at how weathering proceeded over 3.5 billion years," Bindeman said. "Land rising from water changes the albedo of the planet. Initially, Earth would have been dark blue with some white clouds when viewed from space. Early continents added to reflection. Today we have dark continents because of lots of vegetation." Exposure of the new land to weathering, he said, may have set off a sink of greenhouse gases such carbon dioxide, disrupting the radiative balance of the Earth that generated a series of glacial episodes between 2.4 billion and 2.2 billion years ago. That, he said, may have spawned the Great Oxygenation Event in which atmospheric changes brought significant amounts of free oxygen into the air. Rocks were oxidized and became red. Archean rocks are gray. In the absence of much land, he said, photons from the sun interacted with water and heated it. A bright surface, provided by emerging land, would reflect sunlight back into space, creating additional torque on radiative-greenhouse balance and a change in climate. "What we speculate is that once large continents emerged, light would be reflected back into space and initiate runaway glaciation," Bindeman said. "Earth would have seen its first snowfall." Shales are formed by the weathering of crust. "They tell you a lot about the exposure to air and light and precipitation," Bindeman said. "The process of forming shale captures organic products and eventually helps to generate oil. Shales provide us with a continuous record of weathering."

Understanding the evolution of a 400 million-year-old anti-viral protein that first emerged in marine life, is helping researchers get the upper-hand on human immunodeficiency virus (HIV). Researchers at Western University were interested in the origin of a gene that encodes for protein, HERC5, shown to potently inhibit HIV. In a new study published in the Journal of Virology Stephen Barr, PhD, assistant professor at Western's Schulich School of Medicine & Dentistry, shows that the gene first emerged in fish over 400 million-years-ago and has been involved in an evolutionary arms race with viruses ever since. The study shows that over hundreds of millions of years, this battle for survival caused the genes to develop sophisticated shields to block viruses, which in turn forced the viruses to continually evolve and change to circumvent these defences. This provides insight into both how the viruses and the immune system has evolved. Using sequencing technology, Barr and his research team found that the HERC5 gene from this 400 million-year-old fish called a coelacanth encodes for a protein that can potently block the primate version of HIV, known as simian immunodeficiency virus (SIV), but fails to block HIV. "Of course HIV and these modern day viruses that we study aren't present in fish, but ancient versions of them are. So what we assume is that as these ancient retroviruses wreaked havoc on marine life, their immune systems had to develop a defense," Barr explained. "We think that one of those defenses is the HERC family. As retroviruses evolved, eventually giving rise to HIV, different variants of HERC genes emerged to combat these infections." Since these viruses have been in battle for so long, they have had time to learn of ways to get around these shields and as a result became smarter. Consequently, this new level of sophistication likely helped these viruses to jump the species barrier and establish new infections in humans. "By learning the big picture and identifying all the different proteins that can make up this defense against viruses, we can develop a more global approach to advance antiviral drugs. Our future goal is to discover the mechanisms that viruses use to inactivate HERCs and other similar antiviral proteins so that we can exploit this knowledge for the development of novel antiviral drugs," said Barr.

In "How Humans and Apes Are Different and Why It Matters," published in the Journal of Anthropological Research, Agustin Fuentes explores the common ancestry between humans and apes by examining characteristics that the two share. Conversely, Fuentes draws upon anthropological evidence to examine the ways in which the hominin lineage underwent changes during the Pleistocene that led to the emergence of a distinct human niche. Fuentes concludes that these divergent traits -- along with the distinctive space humans inhabit -- give humans the ability to drastically change the environment, other animals, and themselves. Initially featured as the XLIV Journal of Anthropological Research Distinguished Lecture, the article explains why these evolutionary differences are still relevant today. Throughout the article, Fuentes asserts that humans are distinctive, not unique. Humans are classified as mammals and as primates. Both humans and apes belong to a group of primates known as the Hominoidea. As hominoids, humans and apes exhibit a range of similarities, including complex social relationships, large brains, and the capability to utilize tools. Evidence indicates that in the past 2 million years, individuals belonging to the genus Homo experienced significant evolutionary developments. The increasingly complex patterns that resulted served as the foundation of the human niche. A niche consists of the ecosystem an organism inhabits and all of the organism's interactions within that space. Processes occurring within this niche, including the use of fire and new modes of teaching and learning, offered humans greater control over the surrounding environment. Fuentes, in fact, proposes that the most distinctive feature of humanity is its ability to significantly alter ecosystems. Fuentes applies anthropological theory to emphasize the highly significant role humans play in determining the collective future of life on the planet. "The human baseline of creative cooperation, the ability to think, communicate, and collaborate with increasing prowess, transformed us into beings who invented the technologies that support domestication, economies, large-scale societies, warfare, and broad-scale peace. This collaborative and imaginative capacity for creativity also drove the development of religious beliefs and ethical systems, and even the production of artwork. Such capacities fueled and facilitated our ability to compete in more deadly ways. Today humans deploy many of the same capacities that enabled our success as a species to kill/control other humans and manipulate the planet to the brink of ecological devastation," Fuentes writes. While elaborating on our role in the global ecosystem, Fuentes suggests humans should engage with our differences and assume responsibility for ensuring sustainability. "Today we are reshaping the entire world, the globe, the way in which our earth exists. We are also, at more than 7 billion strong, changing the very social landscape of the human experience. We know that inequality and insecurities have broad-scale individual life-history impacts, changing the way in which people experience the world, and changing the ways in which our children grow, or don't. We created a new niche, and now we have to live with and in it, and so does pretty much everything else on the planet."

A team from the Université libre de Bruxelles's centre for archaeological research (CReA-Patrimoine) has completed a significant excavation in Pachacamac, Peru, where they have discovered an intact mummy in especially good condition. Pachacamac's status as a Pre-Colombian pilgrimage site under the Inca empire. is confirmed by further evidence. Peter Eeckhout and his team's latest campaign of archaeological excavations has concluded with an exciting surprise: after nine weeks spent exploring the Pre-Colombian site of Pachacamac, in Peru, the researchers from CReA-Patrimoine (ULB Faculty of Philosophy and Social Sciences) have unearthed a mummy in especially good condition. 'The deceased is still wrapped in the enormous funeral bundle that served as a coffin,' points out professor Peter Eeckhout. 'Discoveries like this one are exceptionally scarce, and this mummy is incredibly well preserved. Samples were collected for carbon-14 dating, but the area in which it was discovered and the type of tomb suggest this individual was buried between 1000 and 1200 AD.' The excavation was carried out as a part of the 'Ychsma' project, named after the region's native people, under the supervision of professor Eeckhout. Three monumental structures were explored during the campaign, including a sanctuary dedicated to the local ancestors. Under Inca rule, in the late 15th century, it appears to have been transformed into a water and healing temple. The archaeologists have discovered many offerings left by worshippers, such as Spondylus shells imported from Ecuador; these are associated with the influx of water during El Niño, and they symbolise fertility and abundance. Before the Inca settled in the area, the sanctuary included large funerary chambers and numerous mummies, most of which were looted during the Spanish conquest. Miraculously, though, one of the chambers was found intact during the latest round of excavations: this is the funeral chamber that held the mummy. Due to how well it was preserved, the researchers will be able to study it without needing to unwrap the bundle. Together with Christophe Moulherat (Musée du Quai Branly, Paris), they will soon examine the mummy using the latest techniques in medical imaging (X-ray scans, axial tomography, 3D reconstruction, etc.). This will enable them to determine the individual's position, any pathologies they might have suffered from, but also what offerings might be inside the bundle. The other structures that were excavated are also related to worship: the first one, an Inca monument intended to host pilgrims and rituals, was built in several phases, each identified with a series of offerings such as seashells and precious objects. The last structure explored was probably one of the 'chapels' for foreign pilgrims, referred to by Spanish monk Antonio de la Calancha in his 17th-century description of the site. There, the excavations also uncovered many 'foundation' offerings, including vases, dogs, and other animals, as well as a platform with a hole in the centre, where an idol was likely placed. The complex appears to have been designed around this idol, involved in religious activities with pilgrims. According to researchers, all these discoveries indicate that Incas made considerable changes to the Pachacamac site, in order to create a large pilgrimage centre on Peru's Pacific coast. 'Deities and their worship played a major part in the life of Pre-Colombian societies,' concludes Peter Eeckhout. 'The Inca understood this very well, and integrated it into how they wielded their power. By promoting empire-wide worship, they contributed to creating a common sense of identity among the many different peoples that made up the empire. Pachacamac is one of the most striking examples of this.'

New research out of South Africa's Wonderwerk Cave led by anthropologists at the University of Toronto (U of T) shows that the climate of the interior of southern Africa almost two million years ago was like no modern African environment -- it was much wetter. In a paper published in Nature Ecology & Evolution, lead author Michaela Ecker, a postdoctoral fellow in the Department of Anthropology at U of T, alongside an international team of scientists that included Michael Chazan, director of U of T's Archaeology Centre, recreated the environmental change in the interior of southern Africa over a span of almost two million years. "The influence of climatic and environmental change on human evolution is largely understood from East African research," said Ecker. "Our research constructed the first extensive paleoenvironmental sequence for the interior of southern Africa using a combination of methods for environmental reconstruction at Wonderwerk Cave." While East African research shows increasing aridity and the spread of grasslands, the study showed that during the same time period, southern Africa was significantly wetter and housed a plant community unlike any other in the modern African savanna -- which means human ancestors were living in environments other than open, arid grasslands. Using carbon and oxygen stable isotope analysis on the teeth of herbivores excavated from the cave, Ecker and her team were able to reconstruct the vegetation from the time the animal was alive and gain valuable insight into the environmental conditions our human ancestors were living in. "Understanding the environment humans evolved in is key to improving our knowledge of our species and its development," said Ecker. "Our work at Wonderwerk Cave demonstrates how humankind existed in multiple environmental contexts in the past -- contexts which are substantially different from the environments of today." This is the latest U of T research out of Wonderwerk Cave, a massive excavation site in the Kuruman Hills of the Northern Cape Province of South Africa. Chazan has previously discovered early evidence of fire by human ancestors, as well as the earliest evidence of cave-dwelling human ancestors, based on excavations carried out by South African archaeologist Peter Beaumont. Research to date has established a chronology for human occupation of the front of the cave stretching back two million years. The findings are described in the study "The palaeoecological context of the Oldowan-Acheulean in southern Africa," published this month in Nature Ecology & Evolution. Research funding was provided by the Social Sciences and Humanities Research Council of Canada, the German Academic Exchange Service, the University of Oxford's Boise Fund Trust and the Quaternary Research Association. Other team members include James Brink and Lloyd Rossouw of the National Museum, Bloemfontein, Liora Horwitz of the Hebrew University of Jerusalem and Julia Lee-Thorp of the University of Oxford. Research at Wonderwerk Cave is carried out in collaboration with the McGregor Museum, Kimberley and under permit from the South African Heritage Resources Agency.

Starting about 7,000 years ago, something weird seems to have happened to men: Over the next two millennia, recent studies suggest, their genetic diversity -specifically, the diversity of their Y chromosomes -- collapsed. So extreme was that collapse that it was as if there was only one man left to mate for every 17 women. Anthropologists and biologists were perplexed, but Stanford researchers now believe they've found a simple -- if revealing -- explanation. The collapse, they argue, was the result of generations of war between patrilineal clans, whose membership is determined by male ancestors. The outlines of that idea came to Tian Chen Zeng, a Stanford undergraduate in sociology, after spending hours reading blog posts that speculated -- unconvincingly, Zeng thought -- on the origins of the "Neolithic Y-chromosome bottleneck," as the event is known. He soon shared his ideas with his high school classmate Alan Aw, also a Stanford undergraduate in mathematical and computational science. "He was really waxing lyrical about it," Aw said, so the pair took their idea to Marcus Feldman, a professor of biology in Stanford's School of Humanities and Sciences. Zeng, Aw and Feldman published their results May 25 in Nature Communications. A cultural culprit It's not unprecedented for human genetic diversity to take a nosedive once in a while, but the Y-chromosome bottleneck, which was inferred from genetic patterns in modern humans, was an odd one. First, it was observed only in men -- more precisely, it was detected only through genes on the Y chromosome, which fathers pass to their sons. Second, the bottleneck is much more recent than other biologically similar events, hinting that its origins might have something to do with changing social structures. Certainly, the researchers point out, social structures were changing. After the onset of farming and herding around 12,000 years ago, societies grew increasingly organized around extended kinship groups, many of them patrilineal clans -- a cultural fact with potentially significant biological consequences. The key is how clan members are related to each other. While women may have married into a clan, men in such clans are all related through male ancestors and therefore tend to have the same Y chromosomes. From the point of view of those chromosomes at least, it's almost as if everyone in a clan has the same father. That only applies within one clan, however, and there could still be considerable variation between clans. To explain why even between-clan variation might have declined during the bottleneck, the researchers hypothesized that wars, if they repeatedly wiped out entire clans over time, would also wipe out a good many male lineages and their unique Y chromosomes in the process. Computing clans To test their ideas, the researchers turned to mathematical models and computer simulations in which men fought -- and died -- for the resources their clans needed to survive. As the team expected, wars between patrilineal clans drastically reduced Y chromosome diversity over time, while conflict between non-patrilineal clans -- groups where both men and women could move between clans -- did not. Zeng, Aw and Feldman's model also accounted for the observation that among the male lineages that survived the Y-chromosome bottleneck, a few lineages underwent dramatic expansions, consistent with the patrilineal clan model, but not others. Now the researchers are looking at applying the framework in other areas -- anywhere "historical and geographical patterns of cultural interactions could explain the patterns you see in genetics," said Feldman, who is also the Burnet C. and Mildred Finley Wohlford Professor. Feldman said the work was a unusual example of undergraduates driving research that was broad both in terms of the academic disciplines spanned -- in this case, sociology, mathematics and biology -- and in terms of its potential implications for understanding the role of culture in shaping human evolution. And, he said, "Working with these talented guys is a lot of fun."

Olive oil is a staple of Italian cuisine. It's been that way for thousands of years. And new chemical analysis conducted on ancient pottery proves the liquid gold has existed in Italy hundreds of years longer than what anthropologists have previously recorded. A team of researchers lead by Davide Tanasi, PhD, assistant professor of history at the University of South Florida, carried out chemical analyses to identify the content of a large jar, found in the 90s by Giuseppe Voza during the excavations at the site of Castelluccio. Conservators at the Archaeological Museum of Siracusa restored and reassembled 400 ceramic fragments, resulting in an egg-shaped 3 ½ foot storage container adorned with rope bands and three vertical handles on each side. At the same architectural site in Castelluccio in Sicily, researchers found two fragmented basins with an internal septum, indicating it was used to keep multiple substances together, but separate, along with a large terracotta cooking plate. "The shape of this storage container and the nearby septum was like nothing else Voza found at the site in Castelluccio," said Dr. Tanasi. "It had the signature of Sicilian tableware dated to the end of the 3rd and beginning of the 2nd millennium BCE (Early Bronze Age). We wanted to learn how it was used, so we conducted chemical analysis on organic residues found inside." In the study published in Analytical Methods, Dr. Tanasi tested the three artifacts using techniques traditionally and successfully used on archaeological pottery: Gas Chromatography, Mass Spectrometry and Nuclear Magnetic Resonance. His team found organic residue from all three samples contained oleic and linoleic acids, signatures of olive oil. They conclude the artifacts are from the Sicilian Early Bronze Age due to their location and peculiar shapes. "The results obtained with the three samples from Castelluccio become the first chemical evidence of the oldest olive oil in Italian prehistory, pushing back the hands of the clock for the systematic olive oil production by at least 700 years," said Tanasi. The only known identification of chemical signatures of olive oil are from storage jars discovered in southern Italy in Cosenza and Lecce believed to be from the 12th and 11th century BCE (Copper Age).

An international team of paleontologists, which includes the University of Bristol, have identified the world's oldest lizard, providing key insight into the evolution of modern lizards and snakes. The 240-million-year-old fossil, Megachirella wachtleri, is the most ancient ancestor of all modern lizards and snakes, known as squamates, the new study, published today in the journal Nature, shows. The fossil, along with data from both living and extinct reptiles -- which involved anatomical data drawn from CT scans and DNA -- suggests the origin of squamates is even older, taking place in the late Permian period, more than 250 million years ago. Tiago Simões, lead author and PhD student from the University of Alberta in Canada, said: "The specimen is 75 million years older than what we thought were the oldest fossil lizards in the entire world and provides valuable information for understanding the evolution of both living and extinct squamates." Currently, there are 10,000 species of lizards and snakes around the world -- twice as many different species as mammals. Despite this modern diversity, scientists did not know much about the early stages of their evolution. Tiago Simões added: "It is extraordinary when you realize you are answering long-standing questions about the origin of one of the largest groups of vertebrates on Earth." Co-author, Dr Michael Caldwell, also from the University of Alberta, added: "Fossils are our only accurate window into the ancient past. Our new understanding of Megachirella is but a point in ancient time, but it tells us things about the evolution of lizards that we simply cannot learn from any of the 9000 or so species of lizards and snakes alive today." Originally found in the early 2000s in the Dolomites Mountains of Northern Italy, researchers considered it an enigmatic lizard-like reptile but could not reach conclusive placement, and it remained nearly unnoticed by the international community. In order to better understand both the anatomy of Megachirella and the earliest evolution of lizards and snakes the authors assembled the largest reptile dataset ever created. The authors combined it with several new anatomical information from Megachirella obtained from high-resolution CT scans. All this new information was analysed using state of the art methods to assess relationships across species, revealing that the once enigmatic reptile was actually the oldest known squamate. Co-author Dr Randall Nydam of the Midwestern University in Arizona, said: "At first I did not think Megachirella was a true lizard, but the empirical evidence uncovered in this study is substantial and can lead to no other conclusion." Co-author Dr Massimo Bernardi from MUSE -- Science Museum, Italy and University of Bristol's School of Earth Sciences, added: "This is the story of the re-discovery of a specimen and highlights the importance of preserving naturalistic specimens in well maintained, publicly accessible collections. "New observations, that could arise from the use of new techniques -- as for the mCT data we have obtained here, could provide a completely new understanding even of long-known specimens."

When and how did the first people come to the Americas? The conventional story says that the earliest settlers came via Siberia, crossing the now-defunct Bering land bridge on foot and trekking through Canada when an ice-free corridor opened up between massive ice sheets toward the end of the last ice age. But with recent archaeological evidence casting doubt on this thinking, scientists are seeking new explanations. One dominant, new theory: The first Americans took a coastal route along Alaska's Pacific border to enter the continent. A new geological study provides compelling evidence to support this hypothesis. By analyzing boulders and bedrock, a research team led by the University at Buffalo shows that part of a coastal migration route became accessible to humans 17,000 years ago. During this period, ancient glaciers receded, exposing islands of southern Alaska's Alexander Archipelago to air and sun -- and, possibly, to human migration. The timing of these events is key: Recent genetic and archaeological estimates suggest that settlers may have begun traveling deeper into the Americas some 16,000 years ago, soon after the coastal gateway opened up. The research will be published online on May 30 in the journal Science Advances. "People are fascinated by these questions of where they come from and how they got there," says lead scientist Jason Briner, PhD, professor of geology in UB's College of Arts and Sciences. "Our research contributes to the debate about how humans came to the Americas. It's potentially adding to what we know about our ancestry and how we colonized our planet." "Our study provides some of the first geologic evidence that a coastal migration route was available for early humans as they colonized the New World," says UB geology PhD candidate Alia Lesnek, the study's first author. "There was a coastal route available, and the appearance of this newly ice-free terrain may have spurred early humans to migrate southward." The findings do not mean that early settlers definitely traversed Alaska's southern coast to spread into the Americas: The project examined just one section of the coast, and scientists would need to study multiple locations up and down the coastline to draw firmer conclusions. Still, the work is exciting because it hints that the seafaring theory of migration is viable. The bones of an ancient ringed seal -- previously discovered in a nearby cave by other researchers -- provide further, tantalizing clues. They hint that the area was capable of supporting human life at the time that early settlers may have been passing through, Briner says. The new study calculates that the seal bones are about 17,000 years old. This indicates that the region was ecologically vibrant soon after the ice retreated, with resources including food becoming available. Co-authors on the research included Briner; Lesnek; Charlotte Lindqvist, PhD, an associate professor of biological sciences at UB and a visiting associate professor at Nanyang Technological University; James Baichtal of Tongass National Forest; and Timothy Heaton, PhD, of the University of South Dakota. A landscape, touched by ice, that tells a story To conduct their study, the scientists journeyed to four islands within the Alexander Archipelago that lie about 200 miles south/southeast of Juneau. The team traveled by helicopter to reach these remote destinations. As soon as the researchers arrived, Briner knew that the islands had once been covered by ice. "The landscape is glacial," he says. "The rock surfaces are smooth and scratched from when the ice moved over it, and there are erratic boulders everywhere. When you are a geologist, it hits you in the face. You know it immediately: The glacier was here." To pinpoint when the ice receded from the region, the team collected bits of rock from the surfaces of boulders and bedrock. Later, the scientists ran tests to figure out how long the samples -- and thus the islands as a whole -- had been free of ice. The researchers used a method called surface exposure dating. As Lesnek explains, "When land is covered by a glacier, the bedrock in the area is hidden under ice. As soon as the ice disappears, however, the bedrock is exposed to cosmic radiation from space, which causes it to accumulate certain chemicals on their surface. The longer the surface has been exposed, the more of these chemicals you get. By testing for these chemicals, we were able to determine when our rock surfaces were exposed, which tells us when the ice retreated. "We use the same dating method for huge boulders called erratics. These are big rocks that are plucked from the Earth and carried to new locations by glaciers, which actually consist of moving ice. When glaciers melt and disappear from a specific region, they leave these erratics behind, and surface exposure dating can tell us when the ice retreated." For the region that was studied, this happened roughly 17,000 years ago. The case for a coastal migration route In recent years, evidence has mounted against the conventional thinking that humans populated North America by taking an inland route through Canada. To do so, they would have needed to walk through a narrow, ice-free ribbon of terrain that appeared when two major ice sheets started to separate. But recent research suggests that while this path may have opened up more than 14,000 years ago, it did not develop enough biological diversity to support human life until about 13,000 years ago, Briner says. That clashes with archaeological findings that suggest humans were already living in Chile about 15,000 years ago or more and in Florida 14,500 years ago. The coastal migration theory provides an alternative narrative, and the new study may mark a step toward solving the mystery of how humans came to the Americas. "Where we looked at it, the coastal route was not only open -- it opened at just the right time," Lindqvist says. "The timing coincides almost exactly with the time in human history that the migration into the Americas is thought to have occurred." The research was funded by a UB IMPACT award, and Lesnek's work on the project, which will contribute to her dissertation, was supported by the National Science Foundation.

A group of University of Otago archaeologists have uncovered the peripheries of a 14th century Māori village in Gisborne, New Zealand. The University's Southern Pacific Archaeological Research (SPAR) unit has recently completed it's third visit to Eastland Port in Gisborne. Heritage New Zealand granted archaeological consent to the Port in 2016, as part of an ongoing redevelopment project. Among the findings in the 2.5 metre-deep excavation were moa bones and other food items, fish hooks manufactured of moa bone and stone tools made of obsidian and chert. The site was located on the edge of an old riverbed. The obsidian (volcanic glass) was used by early Māori settlers as simple cutting tools. The materials found are estimated to date back to the early 1300s. University of Otago Professor of Archaeology Richard Walter says uncovering the site is significant from a scientific and cultural perspective. "We don't know as much about the early occupation around this part of the coastline as we do in other parts of the country," says Professor Walter. "There are not too many of these very, early sites and so this one is filling the gaps." The area has a significant history as the first landing place of waka (canoes) which carried Maori to the district; and the first contact between Māori and explorer James Cook taking place on the river in 1769. Plans are underway to commemorate the 250th anniversary next year. Professor Walter says given the amount of material found at the site, the chances of finding a village within the vicinity are quite high. The site was identified through Heritage New Zealand Pouhere Taonga's archaeological consent process, which regulates the modification or destruction of archaeological sites. "This really is a great example of the archaeological consent process working well where all the groups involved have been working together to get the best possible outcome for this very important place," says Heritage New Zealand Pouhere Taonga's Director Regional Services Pam Bain. Eastland Port received consent from Gisborne District Council in 2017 to develop the wharfside log yard. The site is now being re-covered with the knowledge that any ongoing redevelopments within the port will not affect the historic site. The artefacts and faunal remains are being analysed by the SPAR team in the Otago Archaeology Laboratories in the University's Richardson Building, before the process begins to return them to their rightful owners.

The evolution of larger brains in the last 3 million years played an important role in our ability as a species to think, problem-solve, and develop culture. But the genetic changes behind the expansion that made us human have been elusive. In a pair of papers publishing May 31 in Cell, two teams of researchers identify a gene family, NOTCH2NL, that appears to play an important role in human-specific cortex development and may have been a driving force in the evolution of our large brains. NOTCH2NL genes delay the differentiation of cortical stem cells into neurons, resulting in the production of more neurons across the course of development. The genes are found exclusively in humans, are heavily expressed in neural stem cells of the human cerebral cortex, and are located on a part of the genome implicated in neurodevelopmental disorders. "Our brains got three times as big primarily through the expansion of certain functional areas of the cerebral cortex, and that has to be a fundamental substrate for us becoming human. There's really no more exciting scientific question that I can think of than discovering and decoding the mysterious genetic changes that made us who we are," says David Haussler, co-senior author of one of the papers and a bioinformatician at the University of California, Santa Cruz, and Howard Hughes Medical Institute. The team led by Haussler and co-senior authors Frank Jacobs of the University of Amsterdam and Sofie Salama of University of California, Santa Cruz, and Howard Hughes Medical Institute were comparing genes expressed during brain development in humans and macaque monkeys in stem cell-derived models when they realized that they could detect NOTCH2NL in human cells but not in those of the macaques. Looking at the DNA, they also didn't see it in orangutans and found only truncated, inactive versions in our closest relatives, gorillas and chimpanzees. Reconstructing the evolutionary history of NOTCH2NL genes revealed that a process called gene conversion was likely responsible for repairing a non-functional version of NOTCH2NL, which originally emerged as a partial duplication of an essential neurodevelopmental gene known as NOTCH2. This repair happened only in humans -- and they estimate it happened 3-4 million years ago, around the same time that the fossil record suggests human brains began to expand. After it was repaired, but before we diverged from our common ancestor with Neanderthals, NOTCH2NL was duplicated two more times. The team behind the other paper, led by developmental biologist Pierre Vanderhaeghen of Université Libre de Bruxelles ULB and VIB-KU Leuven, arrived at NOTCH2NL from a related direction, searching for human-specific genes active during fetal brain development using primary tissue. "One of the holy grails of researchers like us is to find out what during human development and evolution is responsible for a bigger brain, particularly the cerebral cortex," Vanderhaeghen says. "Given the relatively fast evolution of the human brain, it is tempting to speculate that newly evolved, human-specific genes may help shape our brain in a species-specific way." Searching for human-specific genes involved in brain development proved challenging because these genes are typically poorly annotated in genome databases and hard to distinguish from more common genes present in other species. The Vanderhaeghen team developed a tailored RNA sequencing analysis for specific and sensitive detection of human-specific genes in human fetal cerebral cortex. This allowed them to identify a repertoire of 35 genes unique to humans that are active during development of the cerebral cortex in humans, including NOTCH2NL genes. They zeroed in on NOTCH2NL in particular because of the importance of its ancestral gene, NOTCH2, in signaling processes that control whether cortical stem cells produce neurons or regenerate more stem cells. And they found that artificially expressing NOTCH2NL in mouse embryos increased the number of progenitor stem cells in the mouse cortex. To better understand what the genes do in humans, the team turned to an in vitro model of cortical development from human pluripotent stem cells to explore NOTCH2NL function. In this model, they found that NOTCH2NL can substantially expand the population of cortical stem cells, which in turn then generate more neurons, a feature expected to distinguish between human and non-human cortical neurogenesis. "From one stem cell, you can either regenerate two progenitor cells, generate two neurons, or generate one progenitor stem cell and one neuron. And what NOTCH2NL does is bias that decision in a slight way towards regenerating progenitors, which can later go on to make more neurons. It's a small early effect with large late consequences, as often happens with evolution," Vanderhaeghen says. Haussler's team looked at what happened when NOTCH2NL wasn't expressed: they deleted it from human stem cells and used them to grow patches of cortex called organoids. In the organoids derived from NOTCH2NL-depleted stem cells, differentiation occurred faster, but the organoids ended up being smaller. "If you lose NOTCH2NL, it leads to premature differentiation of cortical stem cells into neurons, but at the same time the very important stem cell pool gets depleted," says Jacobs. NOTCH2NL's location on the genome, incorrectly mapped until recently, is further support for its role in human brain size. Duplications or deletions at a genome region known as 1q21.1 are known to cause macrocephaly or microcephaly, respectively, and are associated with a range of neurodevelopmental disorders, including ADHD, autism spectrum disorder, and intellectual disability. Haussler's team looked at 11 patients with errors at this locus and found that NOTCH2NL was indeed being duplicated and deleted in the rearrangement events associated with larger and smaller brain size that resulted. "We really wanted the gene to be in the 1q21.1 disease interval, because it made logical sense, but in the incorrect reference genome, it wasn't. And then we found new data, and we realized that it was a mistake in the reference genome! It seldom happens that when you want something that appears to be false to be true, it turns out to actually be true. I don't think something of that level will ever happen again in my career," says Haussler. This part of the genome is simply challenging to sequence and read. "We've been looking under the lamppost in human genetics, as they say, by studying just the regions that were easy to sequence. There's a lot of information in these other regions, and there's a reasonable argument that they are the real cauldron for rapid change over the last few million years," he says. Because NOTCH2NL is something of an evolutionary trade-off between larger brains and 1q21.1 disease susceptibility, the researchers are all quick to point out that there is plenty of healthy variation here, too. "It's a boon that may have enabled us to get a big brain. And yes, it's a bane, because we can have these recombination events that can be bad. But what we found when we developed the technology to really sequence it in individuals is that there are multiple different alleles of this gene. And it's possible that that variation creates the subtlety and plasticity that is important in enabling humans to be human," says Salama. There are still a lot of unknowns when it comes to NOTCH2NL. Haussler's team points out that they were only able to look at the genomes of a small sample of patients and that their organoid models didn't address the later stages of cortical development, at a time when NOTCH2NL might be even more important. Another important question Vanderhaeghen's team wants to address is what other human-specific genes identified here (in particular, those also found in the 1q21.1 region or other genome areas associated with brain diseases) do during brain development. And although both teams were able to show that NOTCH2NL is involved in the well-studied Notch signaling pathway, Vanderhaeghen acknowledges that there is still uncertainty around the exact mechanism by which NOTCH2NL tips the balance between differentiation and regeneration. "What's amazing is that there are many signaling pathways that control the development of the embryo and are completely conserved between species. The Notch signaling pathway is the oldest one. You can find it in every animal you look at. It has been used by developing embryos for as long as animals have existed. And yet, there is a very recent innovation in this pathway specifically in the human lineage, through NOTCH2NL," says Vanderhaeghen. "The locus was building up instability throughout evolution, so the repair of these non-functional NOTCH2NL genes could have happened at any time," says Jacobs. "It could have happened earlier in the primate lineage and had a huge effect on brain development. But it didn't. There's a matter of luck or chance involved that just remains fascinating to me: how you go from something that is quite neutral in our genome to something that has such important function and is used by our species to select for such important properties."

A new genetic study of ancient individuals in the Americas and their contemporary descendants finds that two populations that diverged from one another 18,000 to 15,000 years ago remained apart for millennia before mixing again. This historic "reconvergence" occurred before or during their expansion to the southern continent. The study, reported in the journal Science, challenges previous research suggesting that the first people in the Americas split into northern and southern branches, and that the southern branch alone gave rise to all ancient populations in Central and South America. The study shows for the first time that, deep in their genetic history, many Indigenous people in the southern continent retain at least some DNA from the "northerners" who are the direct ancestors of many Native communities living today in the Canadian east. "It was previously thought that Indigenous South Americans, and indeed most Native Americans, derived from one ancestry related to the Clovis people, who lived about 13,000 years ago," said Cambridge University archaeology professor Toomas Kivisild, who co-led the research with University of Illinois anthropology professor Ripan Malhi. "We now find that all Native populations in North, Central and South America also draw genetic ancestry from a northern branch most closely related to Indigenous peoples of eastern Canada," Kivisild said. "This cannot be explained by activity in the last few thousand years. It is something altogether more ancient." "We are starting to see that previous models of ancient populations were unrealistically simple," Malhi said. The researchers analyzed 91 ancient genomes from sites in California and Canada, along with 45 mitochondrial genomes from present-day Native individuals. The work adds to the evidence that two populations diverged 18,000 to 15,000 years ago. This would have been during or after their migration across the now-submerged land bridge from Siberia along what is now coastal Alaska, the researchers report. Ancient genomes from southwest Ontario show that after the split, Indigenous ancestors representing the northern branch migrated to the Great Lakes region. They may have followed the retreating glacial edges as the most recent ice age began to thaw, the researchers said. Populations representing the southern branch likely continued down the Pacific coast, inhabiting islands along the way, the researchers found. "The ancient Anzick child from Montana also represents the southern branch and is associated with the Clovis culture, which was once thought to be ancestral to all Native Americans," Malhi said. "The analysis of genomes from ancient peoples from Ontario and California allowed us to identify components of the northern and southern branches in contemporary Central and South American genomes. These components were likely the result of a 'reconvergence' of the two branches deep in time." "The blending of lineages occurred either in North America, prior to the expansion south, or as people migrated deeper into the southern continent, most likely following the western coast," said Christiana Scheib, the first author of the study who conducted the work while at the University of Cambridge. "We don't have ancient DNA to corroborate how early this northern ancestral branch arrived."

New research from Northumbria University has revealed that metal-related pollution began in the Balkans more than 500 years before it appeared in western Europe, and persisted throughout the Dark Ages and Medieval Period, meaning the region played a far bigger role in mineral exploitation than previously believed. The study provides a new perspective on both the timing and extent of metallurgy -- the technique of extracting metal from ores prior to heating or working with metals to give them a desired shape -- in the Balkans, and the associated economic change this brought to the region, such as the inception of the Metal Ages. The findings are published in the journal Proceedings of the National Academy of Sciences (PNAS) today (Monday 28 May 2018). The exploitation of mineral resources has a broad range of environmental impacts, including metal-contaminated wastewater and the release of microscopic chemical particles into the atmosphere from mining and smelting. As these particles settle on to the surface of a peat bog, an environment in which the sediment develops year on year, a clear history of the bog's development may be established. Samples recovered from the Crveni Potok peat bog, located on the Serbia/Montenegro border, were geochemically examined by researchers from Northumbria's Department of Geography and Environmental Sciences alongside colleagues from the University of Montpellier and the Romanian Academy. They found the first clear evidence of metal pollution originating from lead in the region dating back to approximately 3600 BC. The evidence is supported by a concurrent rise in charcoal concentration, which suggests an increase in biomass burning which is potentially related to a broad range of economic activities, including fuel production for metal smelting. Previously, the oldest European environmental pollution dating to circa 3000 BC had been found in southern Spain, but the new data from Crveni Potok show that metal pollution was evident in this region of eastern Europe more than 500 years earlier. This evidence is the earliest documented in European environmental records and indicates environmental pollution from metallurgy at a time when Britons were still in the Stone Age. This confirms that the Balkans were not only the birthplace of metallurgy in Europe, but also of metallic pollution. Furthermore, levels of lead pollution decreased dramatically in western Europe after the collapse of the Roman Empire, a feature not observed in this Balkan record. This suggests that the region -- which is metal rich -- should be considered more of a major player in environmental metal pollution through Dark and Middle Ages than previously thought. This contrast between eastern and western Europe indicates that while western Europe was in the 'Dark Ages' there was significant economic development in the Balkan area with high levels of metal environmental pollution throughout the Medieval period. This confirms the large extent and size of the metalworking industry in the Balkans during this era. As part of his PhD research Jack Longman uncovered these findings supervised by Dr Vasile Ersek, Senior Lecturer in Physical Geography in the University's Department of Geography and Environmental Sciences. Dr Ersek explained: "Much of the focus in determining sources of ancient pollution has been on established sources such as the Romans or ancient Greeks, but these findings highlight the crucial role that the Balkan metallurgy has played in the economic development of the area. "Metallurgy and mining is intimately linked to socioeconomic development, therefore improving our knowledge of how these resources were exploited in the past can help us understand better how societies developed over time. In this respect, the peat bog record from Crveni Potok provides a fascinating history of pollution from the early Bronze Age through to the Industrial Revolution." Dr Longman added: "What is most interesting is that after the Roman Empire falls in the third and fourth centuries AD, lead pollution continues and even increases, indicating that the strong mining and smelting culture developed by the Romans was continued by the local population. This goes against the long-held view of barbaric hordes with little technological know-how ousting the Romans leading to the Dark Ages -- as we term the 1,000 years following the Roman period. These Dark Ages may well have been true in much of western Europe, but in the Balkans, it seems that this period was, in fact, rather 'well-lit'."

The invention of agriculture changed humans and the environment forever, and over several thousand years, the practice originated independently in a least a dozen different places. But why did agriculture begin in those places, at those particular times in human history? Using a new methodological approach, researchers at Colorado State University and Washington University in St. Louis have uncovered evidence that underscores one long-debated theory: that agriculture arose out of moments of surplus, when environmental conditions were improving, and populations lived in greater densities. The first-of-its-kind study, "Hindcasting global population densities reveals forces enabling the origin of agriculture," published in Nature Human Behaviour, lends support to existing ideas about the origins of human agriculture. In contrast, they found little support for two other, longstanding theories: One, that during desperate times, when environmental conditions worsened and populations lived at lower densities, agriculture was born out of necessity, as people needed a new way of getting food. And two, that no general pattern exists, but instead the story of agriculture's origins is tied to unique social and environmental conditions in each place. Senior author Michael Gavin, an associate professor in CSU's Department of Human Dimensions of Natural Resources, said the findings and the general methodological approach may help explain other watershed events in human history. "There have been several key threshold events in our history that changed the entire course of our species," Gavin said. "Agriculture is a link to so many other components for what the world is like today for billions of people. This begins to help us explain a key moment in human history." Predicting into the past Studying the depths of human history is challenging, as little data are available when looking back tens of thousands of years. Scientists typically rely on archeological evidence, but getting a broad picture is difficult, since archeological digs cover relatively small areas. To overcome these limitations, the researchers modeled correlations between the environment, cultural traits and population densities of relatively recent foraging societies, which used hunting, fishing and gathering to obtain food. Among the factors they considered as possible predictors of population density: environmental productivity; environmental stability; the average distance travelled when people in a community moved to a new location; whether people owned land or other resources; and distance to the nearest coast. This model, the team found, did a remarkably good job at predicting recent population densities, which led the researchers to pair the model with data on past climate. In doing so, they could hindcast, or predict into the past, the potential population density of the entire globe dating back thousands of years. Population maps This study was the first to produce maps of potential population densities dating back as far as 21,000 years. The researchers used these maps to examine conditions that existed in each of the 12 centers of origin, at the point in time agricultural practices began. Patrick Kavanagh, a CSU postdoctoral scientist and one of the study's lead authors, said the different centers of origin for agriculture all showed improving environmental conditions and increasing population densities. "All regions that developed agriculture showed the same pattern," he said. Researchers believe that improving environmental conditions may have allowed people the luxury of tinkering with new ideas, and that having more people living in one place would allow ideas to be shared and honed, with sparks of innovation following. While the researchers found commonalities in the surplus aspect of what was occurring in different locations, that doesn't mean the exact same conditions existed in each center of origin. Socially, the places and people studied were probably very different. In addition, the timing of when agriculture began in these major centers varied over thousands of years, and the species of plants they were working with was different. But, amazingly, although the centers of origin varied in time by thousands of years and ranged from the New Guinea Highlands to Central America and the Middle East, they all had one thing in common: improving environmental conditions, and the potential for higher population densities. "In all of these major origin centers of agriculture, there were some critical environmental changes that needed to occur," Kavanagh added. "Environmental conditions needed to improve -- which we saw in all 12 centers of origin -- despite variation in the timing and the diverse geographic locations in which they occurred." The research team is now exploring other applications for the maps they produced. "It is amazing to examine these maps of the potential population density of the world dating back tens of thousands of years," said Gavin. "We could potentially create them going back to the dawn of our species. This provides a new tool to explore many unanswered questions about human history."

Chemical analysis of the remains of rats from archaeological sites spanning the last 2000 years on three Polynesian island systems has shown the impact that humans have had on local environments. The analysis by an international team of scientists allowed the researchers to reconstruct the rats' diets -- and through them the changes made by humans to local ecosystems, including native species extinctions and changes to food webs and soil nutrients. Earth has arguably entered a new geological epoch called the Anthropocene, an era in which humans are bringing about significant, lasting change to the planet. While most geologists and ecologists place the origins of this era in the last 50 to 300 years, many archaeologists have argued that far-reaching human impacts on geology, biodiversity, and climate extend back millennia into the past. Ancient human impacts are often difficult to identify and measure compared to those happening today or in recent history. A new study published in the Proceedings of the National Academy of Sciences by researchers at the Max Planck Institute for the Science of Human History in Jena and the University of California, Berkeley advances a new method for detecting and quantifying human transformations of local ecosystems in the past. Using state of the art methods, researchers searched for clues about past human modifications of island ecosystems from an unusual source -- the bones of long-dead rats recovered from archaeological sites. One of the most ambitious and widespread migrations in human history began c. 3000 years ago, as people began voyaging across the Pacific Ocean -- beyond the visible horizon -- in search of new islands. By around 1000 years ago, people had reached even the most remote shores in the Pacific, including the boundaries of the Polynesian region: the islands of Hawai'i, Rapa Nui (Easter Island) and Aotearoa (New Zealand). Not knowing what they would encounter in these new lands, early voyagers brought with them a range of familiar plants and animals, including crops such as taro, breadfruit, and yams, and animals including the pig, dog, and chicken. Amongst the new arrivals was also the Pacific rat (Rattus exulans), which was carried to almost every Polynesian island on these early voyages, perhaps intentionally as food, or equally likely, as a hidden "stowaway" aboard long-distance voyaging canoes. The arrival of the rat had profound impacts on island ecosystems. Pacific rats hunted local seabirds and ate the seeds of endemic tree species. Importantly, commensal animals like the Pacific rat occupy a unique position in human ecosystems. Like domestic animals, they spend most of their time in and around human settlements, surviving on food resources produced or accumulated by people. However, unlike their domestic counterparts, these commensal species are not directly managed by people. Their diets thus provide insights into the food available in human settlements as well as changes to island ecosystems more broadly. But how to reconstruct the diet of ancient rats? To do this, the researchers examined the biochemical composition of rat bones recovered from archaeological sites across three Polynesian island systems. Carbon isotope analysis of proteins preserved in archaeological bone indicates the types of plants consumed, while nitrogen isotopes point to the position of the animal in a food web. Nitrogen isotopes are also sensitive to humidity, soil quality, and land use. This study examined the carbon and nitrogen isotopes of archaeological Pacific rat remains across seven islands in the Pacific, spanning roughly 2000 years of human occupation. The researchers' results demonstrate the impacts of processes like human forest clearance, hunting of native avifauna (in particular land birds and seabirds) and the development of new, agricultural landscapes on food webs and resource availability. A near-universal pattern of changing rat bone nitrogen isotope values through time was linked to native species extinctions and changes in soil nutrient cycling after people arrived on the islands. In addition, significant changes in both carbon and nitrogen isotopes correspond with agricultural expansion, human site activity, and subsistence choices. "We have many strong lines of archaeological evidence for humans modifying past ecosystems as far back as the Late Pleistocene," says lead author Jillian Swift, of the Max Planck Institute for the Science of Human History. "The challenge is in finding datasets that can quantify these changes in ways that allow us to compare archaeological and modern datasets to help predict what impacts human modifications will have on ecosystems in the future." Prof. Patrick V. Kirch of the University of California, Berkeley, who supervised the study and led excavations on Tikopia and Mangareva, remarked that "the new isotopic methods allow us to quantify the ways in which human actions have fundamentally changed island ecosystems. I hardly dreamed this might be possible back in the 1970s when I excavated the sites on Tikopia Island." "Commensal species, such as the Pacific rat, are often forgotten about in archaeological assemblages. Although they are seen as less glamorous 'stowaways' when compared to domesticated animals, they offer an unparalleled opportunity to look at the new ecologies and landscapes created by our species as it expanded across the face of the planet," added Patrick Roberts of the Max Planck Institute for the Science of Human History, a co-author on the paper. "The development and use of stable isotope analysis of commensal species raises the possibility of tracking the process of human environment modification, not just in the Pacific, but around the world where they are found in association with human land use." The study highlights the extraordinary degree to which people in the past were able to modify ecosystems. "Studies like this clearly highlight the human capacity for 'ecosystem engineering,'" notes Nicole Boivin, coauthor of the study and Director of the Department of Archaeology at the Max Planck Institute for the Science of Human History. "We clearly have long had the capability as a species of massively transforming the world around us. What's new today is our ability to understand, measure, and alleviate these impacts."

The remains of World War II naval battle sites can be found under water, but most have not yet been subject to archaeological investigation. A new International Journal of Nautical Archaeology study provides precise geographic information for the preservation, long-term research, and future use of a historically important World War II battle site on the seafloor off the coast of Okinawa, Japan. The study focuses on the USS Emmons, a 106m US Navy Gleaves-class destroyer minesweeper that sank in 40m of water off Okinawa Island after kamikaze attack in 1945. A record of the site was made using an innovative method incorporating precise control points obtained from high-resolution multibeam echosounding bathymetry to generate 3D models using structure-from-motion photogrammetry. The 3D models produced can be used for sharing information about this underwater cultural heritage and for future monitoring of the archaeological remains. "This article is not only presenting an innovative methodology for precise 3D mapping of the seafloor. We hope it also serves as a bridge to peace for both Japan and the U.S. and provides materials for future education," said lead author Prof. Hironobu Kan, of Kyushu University, in Japan.

It's a whole new way of thinking about sensors. The tiny fibers developed at EPFL are made of elastomer and can incorporate materials like electrodes and nanocomposite polymers. The fibers can detect even the slightest pressure and strain and can withstand deformation of close to 500% before recovering their initial shape. All that makes them perfect for applications in smart clothing and prostheses, and for creating artificial nerves for robots. The fibers were developed at EPFL's Laboratory of Photonic Materials and Fiber Devices (FIMAP), headed by Fabien Sorin at the School of Engineering. The scientists came up with a fast and easy method for embedding different kinds of microstructures in super-elastic fibers. For instance, by adding electrodes at strategic locations, they turned the fibers into ultra-sensitive sensors. What's more, their method can be used to produce hundreds of meters of fiber in a short amount of time. Their research has just been published in Advanced Materials. Heat, then stretch To make their fibers, the scientists used a thermal drawing process, which is the standard process for optical-fiber manufacturing. They started by creating a macroscopic preform with the various fiber components arranged in a carefully designed 3D pattern. They then heated the preform and stretched it out, like melted plastic, to make fibers of a few hundreds microns in diameter. And while this process stretched out the pattern of components lengthwise, it also contracted it crosswise, meaning the components' relative positions stayed the same. The end result was a set of fibers with an extremely complicated microarchitecture and advanced properties. Until now, thermal drawing could be used to make only rigid fibers. But Sorin and his team used it to make elastic fibers. With the help of a new criterion for selecting materials, they were able to identify some thermoplastic elastomers that have a high viscosity when heated. After the fibers are drawn, they can be stretched and deformed but they always return to their original shape. Rigid materials like nanocomposite polymers, metals and thermoplastics can be introduced into the fibers, as well as liquid metals that can be easily deformed. "For instance, we can add three strings of electrodes at the top of the fibers and one at the bottom. Different electrodes will come into contact depending on how the pressure is applied to the fibers. This will cause the electrodes to transmit a signal, which can then be read to determine exactly what type of stress the fiber is exposed to -- such as compression or shear stress, for example," says Sorin. Artificial nerves for robots Working in association with Professor Dr. Oliver Brock (Robotics and Biology Laboratory, Technical University of Berlin), the scientists integrated their fibers into robotic fingers as artificial nerves. Whenever the fingers touch something, electrodes in the fibers transmit information about the robot's tactile interaction with its environment. The research team also tested adding their fibers to large-mesh clothing to detect compression and stretching. "Our technology could be used to develop a touch keyboard that's integrated directly into clothing, for instance" says Sorin. The researchers see many other potential applications. Especially since the thermal drawing process can be easily tweaked for large-scale production. This is a real plus for the manufacturing sector. The textile sector has already expressed interest in the new technology, and patents have been filed.

Experts at recognizing faces often play a crucial role in criminal cases. A photo from a security camera can mean prison or freedom for a defendant -- and testimony from highly trained forensic face examiners informs the jury whether that image actually depicts the accused. Just how good are facial recognition experts? Would artificial intelligence help? A study appearing today in the Proceedings of the National Academy of Sciences has brought answers. In work that combines forensic science with psychology and computer vision research, a team of scientists from the National Institute of Standards and Technology (NIST) and three universities has tested the accuracy of professional face identifiers, providing at least one revelation that surprised even the researchers: Trained human beings perform best with a computer as a partner, not another person. "This is the first study to measure face identification accuracy for professional forensic facial examiners, working under circumstances that apply in real-world casework," said NIST electronic engineer P. Jonathon Phillips. "Our deeper goal was to find better ways to increase the accuracy of forensic facial comparisons." The team's effort began in response to a 2009 report by the National Research Council, "Strengthening Forensic Science in the United States: A Path Forward," which underscored the need to measure the accuracy of forensic examiner decisions. The NIST study is the most comprehensive examination to date of face identification performance across a large, varied group of people. The study also examines the best technology as well, comparing the accuracy of state-of-the-art face recognition algorithms to human experts. Their result from this classic confrontation of human versus machine? Neither gets the best results alone. Maximum accuracy was achieved with a collaboration between the two. "Societies rely on the expertise and training of professional forensic facial examiners, because their judgments are thought to be best," said co-author Alice O'Toole, a professor of cognitive science at the University of Texas at Dallas. "However, we learned that to get the most highly accurate face identification, we should combine the strengths of humans and machines." The results arrive at a timely moment in the development of facial recognition technology, which has been advancing for decades, but has only very recently attained competence approaching that of top-performing humans. "If we had done this study three years ago, the best computer algorithm's performance would have been comparable to an average untrained student," Phillips said. "Nowadays, state-of-the-art algorithms perform as well as a highly trained professional." The study itself involved a total of 184 participants, a large number for an experiment of this type. Eighty-seven were trained professional facial examiners, while 13 were "super recognizers," a term implying exceptional natural ability. The remaining 84 -- the control groups -- included 53 fingerprint examiners and 31 undergraduate students, none of whom had training in facial comparisons. For the test, the participants received 20 pairs of face images and rated the likelihood of each pair being the same person on a seven-point scale. The research team intentionally selected extremely challenging pairs, using images taken with limited control of illumination, expression and appearance. They then tested four of the latest computerized facial recognition algorithms, all developed between 2015 and 2017, using the same image pairs. Three of the algorithms were developed by Rama Chellappa, a professor of electrical and computer engineering at the University of Maryland, and his team, who contributed to the study. The algorithms were trained to work in general face recognition situations and were applied without modification to the image sets. One of the findings was unsurprising but significant to the justice system: The trained professionals did significantly better than the untrained control groups. This result established the superior ability of the trained examiners, thus providing for the first time a scientific basis for their testimony in court. The algorithms also acquitted themselves well, as might be expected from the steady improvement in algorithm performance over the past few years. What raised the team's collective eyebrows regarded the performance of multiple examiners. The team discovered that combining the opinions of multiple forensic face examiners did not bring the most accurate results. "Our data show that the best results come from a single facial examiner working with a single top-performing algorithm," Phillips said. "While combining two human examiners does improve accuracy, it's not as good as combining one examiner and the best algorithm." Combining examiners and AI is not currently used in real-world forensic casework. While this study did not explicitly test this fusion of examiners and AI in such an operational forensic environment, results provide an roadmap for improving the accuracy of face identification in future systems. While the three-year project has revealed that humans and algorithms use different approaches to compare faces, it poses a tantalizing question to other scientists: Just what is the underlying distinction between the human and the algorithmic approach? "If combining decisions from two sources increases accuracy, then this method demonstrates the existence of different strategies," Phillips said. "But it does not explain how the strategies are different." The research team also included psychologist David White from Australia's University of New South Wales.

The new field of biohybrid robotics involves the use of living tissue within robots, rather than just metal and plastic. Muscle is one potential key component of such robots, providing the driving force for movement and function. However, in efforts to integrate living muscle into these machines, there have been problems with the force these muscles can exert and the amount of time before they start to shrink and lose their function. Now, in a study reported in the journal Science Robotics, researchers at The University of Tokyo Institute of Industrial Science have overcome these problems by developing a new method that progresses from individual muscle precursor cells, to muscle-cell-filled sheets, and then to fully functioning skeletal muscle tissues. They incorporated these muscles into a biohybrid robot as antagonistic pairs mimicking those in the body to achieve remarkable robot movement and continued muscle function for over a week. The team first constructed a robot skeleton on which to install the pair of functioning muscles. This included a rotatable joint, anchors where the muscles could attach, and electrodes to provide the stimulus to induce muscle contraction. For the living muscle part of the robot, rather than extract and use a muscle that had fully formed in the body, the team built one from scratch. For this, they used hydrogel sheets containing muscle precursor cells called myoblasts, holes to attach these sheets to the robot skeleton anchors, and stripes to encourage the muscle fibers to form in an aligned manner. "Once we had built the muscles, we successfully used them as antagonistic pairs in the robot, with one contracting and the other expanding, just like in the body," study corresponding author Shoji Takeuchi says. "The fact that they were exerting opposing forces on each other stopped them shrinking and deteriorating, like in previous studies." The team also tested the robots in different applications, including having one pick up and place a ring, and having two robots work in unison to pick up a square frame. The results showed that the robots could perform these tasks well, with activation of the muscles leading to flexing of a finger-like protuberance at the end of the robot by around 90°. "Our findings show that, using this antagonistic arrangement of muscles, these robots can mimic the actions of a human finger," lead author Yuya Morimoto says. "If we can combine more of these muscles into a single device, we should be able to reproduce the complex muscular interplay that allow hands, arms, and other parts of the body to function."

The daughter of country music star Wynonna Judd is behind bars after being sentenced to eight years in prison. A spokesperson for the West Tennessee State Penitentiary confirmed to editors at Entertainment Tonight that Grace Pauline Kelley was sentenced and imprisoned in April (18). The 22-year-old is reportedly serving time for violating probation after she left a court-mandated drug recovery program last November ahead of her scheduled completion. In May 2017, Grace reportedly pleaded guilty to the manufacturing, delivery, sale and possession of methamphetamine at Williamson County Court in Texas. As part of a plea deal, she was given a suspended sentence of 11 months and 29 days in jail, which would be served on probation providing she spent 30 days behind bars and 180 days at an in-house rehab centre for the drug recovery program she later left. Grace, who Wynonna shares with her first husband Arch Kelley III, is due to be released on 10 August 2025 but becomes eligible for parole in 2019. It's the latest development in a series of run-ins with the authorities for the troubled young woman, who has a lengthy history of drug-related charges. In December 2015, she was arrested in a Walgreens parking lot in Nashville and in May 2016 was charged with promotion of meth manufacture to which she pleaded guilty to the lesser charge of possessing meth, according to Radar Online. The news outlet also reported that the same year, she was arrested in Alabama for being a “fugitive from justice,” and her probation was revoked.

Gorillaz are this week's UK Represent artist on Julie Adenuga’s Beats 1 show on Apple Music. Damon Albarn from the band spoke to Julie on yesterday’s show about the band’s new album, ‘The Now Now’, which is released on Friday. On releasing the new album... Does anyone even recognise them as albums anymore? Or am I just completely out of date, out of sync, out of place, just out basically…I just wanted to have some tunes to play this year, there was a real demand to come back this year and I wasn’t up for doing it unless I had something fresh to play. I suppose from the last record I kind of forgot to include myself, it wasn’t intentional, I think we just got so carried away with collaborating, maybe that was just the idea that was in our heads at the time. But I suppose this is sort of like a ‘reset record’. On the vibe of the record... I am yeah [on every single song], and I’m trying to be quite “up" which is quite hard for me to be sort of optimistic but I think I’ve managed it on this record. Naturally, I don’t really make happy music, but somehow this record sort of turned out quite happy...I was in America and I think what it was, was that I made it in hotels, but at the top of hotels so I had great views. On the Gorillaz characters... They have got older. Noodle has turned into a woman; she was a child, now she’s a woman. Murdoch is in prison and has been replaced by Ace who originally was in the Gangreen Gang who were a part of The Powerpuff Girls. 2D’s hair is kind of slightly receding and Russell fluctuates in weight depending on which album cycle he is in. This record, because it’s got my voice, which is 2D’s voice, it really does focus the characters around the record more so than ‘Humanz’ which has so many guests. It’s quite hard for the characters to sort of pop out, but it’s a lot easier around this record. So the narrative around this record is sort of effortless. In fact, the record was pretty effortless. It was one of the easiest records I’ve made. And it’s rare, they’re not always easy.

50 Cent has sparked outrage after he posted a series of social media posts mocking actor Terry Crews over his sexual assault claims. Deadpool 2 actor Terry gave evidence before the U.S. Senate Judiciary Committee on Tuesday (26Jun18) to advocate for the Sexual Assault Survivors’ Bill of Rights, after he alleged he had been sexually assaulted by Hollywood agent Adam Venit while at a party with his wife in 2016. It prompted the rapper 50, real name Curtis Jackson, to post a series of since-deleted tweets making light of the claim, suggesting the actor's size could have somehow prevented the alleged assault. In a picture showing the 49-year-old actor without his shirt on, the Candy Shop singer wrote: "I got raped," and: "My wife just watched." Another image showed the star with a rose in his mouth and the words: "Gym time," to which 50 had added the caption: “LOL, What the f**k is going on out here man? Terry: l froze in fear, they would have had to take me to jail. get the strap.” But The Expendables star remained composed when confronted with the tweets by TMZ, insisting: “Well, I love 50 Cent. I listen to his music while I’m working out." When pressed again about what the 42-year-old wrote, and specifically the comment "how big you are", the actor responded: “I prove that size doesn’t matter when it comes to sexual assault.” But fans of the actor were not impressed, and took to social media to air their disgust. "As someone who was a fan of 50 cent since I was a kid, I’m disgusted at his ignorance and insensitive response to Terry Crew’s sexual assault story," one user wrote. "To laugh and make jokes about such a serious matter is one of the main reasons why sexual assault victims are afraid to speak up." According to Variety, Terry filed a lawsuit against agent Venit and employer William Morris Endeavor, who he accused of grabbing his genitals at the event. The agent was suspended for 30 days in October last year, Deadline reported.

Nicki Minaj has vowed to help fellow rapper Lil Uzi Vert set up a foundation to help those affected by gun violence, like the family of late hip-hop star XXXTentacion. The 20-year-old, real name Jahseh Dwayne Ricardo Onfroy, was shot in his car outside the RIVA Motorsports dealership in Deerfield Beach, Florida on 18 June (18), and he subsequently died from his injuries in hospital. His mother Cleopatra Bernard later hinted that he had been expecting a baby with his girlfriend. On Tuesday night (26Jun18), Bad and Boujee star Lil Uzi Vert told fans he wanted to set up a foundation in the rapper's honour to help his child and family, and anybody else who had been affected by gun violence, and asked celebrities to join the cause. Nicki, who featured on his track The Way Life Goes, came forward to offer support, tweeting, "I’d be honored to help babe. Hit me w|the info (praying hands emoji)," and he replied, "Thank you Nicki imma hit you up (love heart)." In his original series of tweets, the 23-year-old, real name Symere Woods, wrote, "Been speaking to @xxxtentacion family. I want to start a fund/foundation to make sure his child and family are well taken care of not just temporary but for life. I don’t care if you didn’t know him he is part of the hip hop / rock community I NEED HELP from celebrities Please. "Trust me this fund/foundation will be for all young entertainers and young men and women that die from gun violence etc... We can buy chains and watches and cars WE ALSO CAN DONATE AND GIVE AND SUPPORT." The hip-hop star concluded by encouraging members of the rap community to help out even if they don't like or talk to each other. "I could handle this Alone but I just wanna make sure if anything happens to me Yall hit my Mommy up like yall hit for features (money bag emoji)," he wrote. XXXTentacion will be laid to rest on Wednesday at the BB&T Center in Sunrise, Florida.

Demi Lovato has raised over $7,500 (£5,700) after launching a Gay & Lesbian Alliance Against Defamation (GLAAD) fundraiser in honour of Pride month. The singer took to social media on Tuesday (26Jun18) to encourage fans to donate to the organisation and quickly surpassed her goal of $5,000 (£3,800) within hours. Lovato started the campaign to coincide with Pride, which is celebrated annually during the month of June to pay tribute to the 1969 Stonewall riots that took place in New York during a transformative fight for gay rights. "I’m celebrating Pride by raising money for GLAAD, an organization that has been fighting for LGBTQ+ (lesbian, gay, bisexual, and transgender) inclusion and justice since 1985," she posted on Facebook. “Join me in supporting a good cause... your contribution will make an impact, whether you donate $5 or $500. Every little bit helps.” Members of GLAAD work to ensure the gay community is properly represented in the media. In 2016, Lovato was recognised during the organisation's annual Media Awards for her dedicated to the LGBTQ community. The 25-year-old star opened up about her refusal to label her own sexuality last September (17), stating, "I love who I love. I just feel like everyone's always looking for a headline and they always want their magazine or TV show or whatever to be the one to break what my sexuality is." Demi previously hit headlines with her 2015 hit Cool for the Summer, which features lines including: "It's OK/ I'm a little curious too, Don't be scared 'cause I'm your body type/Just something that we wanna try." She later revealed the tune was based on personal experience, but refused to confirm she'd had a lesbian encounter, telling British talk show host Alan Carr, "I am not confirming and I'm definitely not denying. All of my songs are based off of personal experiences. I don't think there's anything wrong with experimentation at all."