Antarctic hotspot: Fin whales favour the waters around Elephant Island

Sound recordings show: the baleen whales use the island's krill-rich waters virtually year-round, which is why it needs to be protected

ALFRED WEGENER INSTITUTE, HELMHOLTZ CENTRE FOR POLAR AND MARINE RESEARCH

Research News

 

During the era of commercial whaling, fin whales were hunted so intensively that only a small percentage of the population in the Southern Hemisphere survived, and even today, marine biologists know little about the life of the world's second-largest whale. That makes the findings of researchers from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) and the Johann Heinrich von Thünen Institute for Sea Fisheries, which show that a large number of the baleen whales regularly frequent the krill-rich waters surrounding Elephant Island, all the more welcome. Evidence for this is provided by underwater sound recordings from the region, where in the peak month of May, so many fin whale vocalizations can be heard that the individual calls merge into a veritable chorous of sound, as the research team now reports in the journal Royal Society Open Science. In view of this, the marine biologists call for protective measures for this important habitat so as not to jeopardise the apparent recovery of the fin whale population.

Fin whales are still rare and, according to the textbooks, normally appear in groups of three to a maximum of seven. As such, AWI marine biologist Elke Burkhardt was all the more surprised when in the late southern summer of 2012, while on an expedition in the Scotia Sea on board the German research icebreaker Polarstern, she counted more than 100 hundred fin whales in the waters north of Elephant Island. Was this a chance find, or did it mean that such large numbers of the world's second-largest baleen whale gathered here regularly? And if so, why?

To answer this question, in January 2013 Burkhardt and her team installed a mooring with two underwater acoustic recorders and a device used to determine the food supply in the coastal area northwest of the island. Over a period of three years, from January 2013 to February 2016, the instruments recorded the soundscape of the underwater world and gathered data on the food supply in the upper water column. By doing so, they helped identify one of the southern fin whale's most important habitats.

"Our observations from Polarstern were no fluke. As our results show, from December to August the whales regularly inhabit the waters surrounding Elephant Island. Here they not only hunt Antarctic krill, but also search for mates. Our recorders registered the most fin whale calls precisely in the season when the breeding period begins for the Southern Hemisphere population," Burkhardt reports.

Fin whales can be identified by the low-frequency calls that are typical of the species: "Humans would probably only perceive them as vibrations in the pit of the stomach, since their central frequency is roughly 20 hertz, making them exceptionally deep," explains Burkhardt. Male Fin whales that are ready to mate and want to attract females emit these bass sounds in rapid, regular intervals. "Their courtship behaviour may also explain why, in the month of May, our instruments recorded so many of these calls that they merged and were barely discernable as individual sounds," says the AWI marine biologist.

New arguments in favour of a marine protected area around Elephant Island

She was thrilled to discover the numerous fin whales around Elephant Island: "If this aggregation really is an indication that the fin whale population is growing, it would represent a notable achievement for the international whaling moratorium, which entered into effect 35 years ago," she explains.

At the same time, the new findings are a cause for concern. "On the one hand, Antarctic krill are extensively fished in the Scotia Sea; on the other, the region, which is extremely important for fin whales, is frequently visited by cruise ships. That makes it all the more important to comprehensively protect the waters around Elephant Island, and to regulate both krill fishing and tourism in order to avoid harming the fin whale stocks," Burkhardt says. Accordingly, the soundscape should be recorded at regular intervals to document any changes in the population.

Where do the fin whales from Elephant Island spend the winter?

While analysing the underwater recordings, the research team discovered another interesting detail: the 20-Hz pulse also contains an accompanying sound with a frequency of 86 Hz. This in turn resembles the fin whale calls that Chilean marine biologists had previously recorded off the coast of central Chile - particularly at the time of year when the instruments at Elephant Island rarely recorded the sounds of the baleen whales. Was it possible that the same whale population produced the sounds in both regions, and that it moved back and forth between the South Shetland Islands, which Elephant Island belongs to, and the Pacific coast of Chile?

"It is believed that fin whales produce population-specific accompanying higher frequency sounds, which can be used to distinguish between different populations. If this is the case, we can likely conclude that those fin whales that inhabit the waters surrounding Elephant Island in the southern summer may give birth to their calves in the warmer waters off Chile's Pacific coast later in the year, and that these whales regularly travel between the two regions," says Burkhardt.

However, to verify this, further studies are required. To this end, the Bremerhaven-based research team has installed additional underwater recording devices, which will tentatively be retrieved in 2022, in the vicinity of the island. The marine biologists are currently analysing their underwater recordings from the period since 2016. And the first excerpts are promising: in the summers after 2016, Elephant Island continued to be a favourite gathering place for fin whales.

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Original Publication: Elke Burkhardt, Ilse Van Opzeeland, Boris Cisewski, Ramona Mattmüller, Marlene Meister, Elena Schall, Stefanie Spiesecke, Karolin Thomisch, Sarah Zwicker and Olaf Boebel (2021): Seasonal and diel cycles of fin whale acoustic occurrence near Elephant Island, Antarctica. R. Soc. Open Sci. 8: 201142. https://doi.org/10.1098/rsos.201142

Plastic in Galapagos seawater, beaches and animals

UNIVERSITY OF EXETER

Research News

 

IMAGE: PLASTIC SAMPLING ON A BEACH IN GALAPAGOS. view more 

CREDIT: ADAM PORTER

Plastic pollution has been found in seawater, on beaches and inside marine animals at the Galapagos Islands.

A new study - by the University of Exeter, Galapagos Conservation Trust (GCT) and the Galapagos Science Center - found plastic in all marine habitats at the island of San Cristobal, where Charles Darwin first landed in Galapagos.

At the worst "hotspots" - including a beach used by the rare "Godzilla" marine iguana - more than 400 plastic particles were found per square metre of beach.

Plastic was also found inside more than half of the marine invertebrates (such as barnacles and urchins) studied, and on the seabed.

The findings suggest most plastic pollution in Galapagos - a world-famous biodiversity haven - arrives on ocean currents.

The study also identifies Galapagos marine vertebrates most at risk from swallowing plastic or getting entangled - including scalloped hammerheads, whale sharks, sea lions and sea turtles.

"The pristine image of Galapagos might give the impression that the islands are somehow protected from plastic pollution, but our study clearly shows that's not the case," said Dr Ceri Lewis, of Exeter's Global Systems Institute.

"The highest levels of plastic we found were on east-facing beaches, which are exposed to pollution carried across the eastern Pacific on the Humboldt Current.

"These east-facing beaches include Punta Pitt, a highly polluted site that is home to Godzilla marine iguanas which - like so much Galapagos wildlife - are found nowhere else in the world.

"There are less than 500 Godzilla marine iguanas in existence, and it's concerning that they are living alongside this high level of plastic pollution."

Speaking about microplastic particles found inside marine invertebrates, lead author Dr Jen Jones, of GCT, said: "These animals are a crucial part of food webs that support the larger species that famously live on and around the Galapagos Islands.

CAPTION

A sea lion playing with a piece of plastic.

CREDIT

Adam Porter

"The potential health effects of plastic ingestion on marine animals are largely unknown, and more research is needed."

The study's findings include:

- Just 2% of "macroplastic" (items and fragments larger than 5mm) was identified as coming from the islands. The true figure could be higher, but the findings strongly suggest most plastic arrives on ocean currents.

- These macroplastics were found at 13 of 14 sandy beaches studied, with 4,610 items collected in total. Large microplastics (1-5mm) sieved from the surface 50mm of sand were found at 11 of 15 sites tested.

- Significant accumulations of plastic were found in key habitats including rocky lava shores and mangroves.

- Microplastics were found in low concentrations in all seabed and seawater samples, with higher concentrations at the harbour suggesting some local input.

- All seven marine invertebrate species examined were found to contain microplastics. 52% of the 123 individuals tested contained plastic.

CAPTION

A piece of plastic tape found lying on an urchin.

CREDIT

Adam Porter

To analyse the possible impact of plastic on Galapagos marine vertebrates such as sea lions and turtles, the researchers reviewed 138 studies of plastic ingestion and entanglement among such species worldwide.

They also considered where in Galapagos each species is known to be found, and considered their conservation status on the IUCN Red List of Threatened Species.

Based on this, the study identifies 27 species in need of urgent monitoring and mitigation.

Dr Jones, who led the study as part of her PhD at Exeter, said: "Our study highlights how far plastic pollution travels, and how it contaminates every part of marine ecosystems.

"Given the level of pollution we have found in this remote location, it's clear that plastic pollution needs to stop at source.

"You can't fix the problem just by cleaning beaches."

Dr David Santillo, of the Greenpeace Research Laboratories at the University of Exeter, said: "This situation is only going to get worse if we don't dramatically change our use of plastics."

Last year, the research team won a £3.3 million grant from the UK government to investigate and address plastic pollution in the Eastern Pacific.

However, the grant has been reduced by 64% and may be cancelled after the first year due to Official Development Assistance (ODA) cuts announced in March.

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Access to Spotlight 400 imaging FT-IR microscope used in this study was made possible under a Research Partnership Agreement between the Greenpeace Research Laboratories and PerkinElmer.

To make a donation to GCT's Plastic Pollution Free Galapagos programme, click here.

The new study, funded by GCT and the Royal Geographical Society and published in the journal Science of the Total Environment, is entitled: "Plastic contamination of a Galapagos Island (Ecuador) and the relative risks to native marine species."

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy o

 

Horror films as a reimagined space for healing

Researcher analyzes trauma experienced by the 'final girl'

OHIO STATE UNIVERSITY

Research News

 

COLUMBUS, Ohio - If you've watched a slasher movie, you've probably been exposed to the final girl trope - a closing scene of a white, suburban teenage girl who triumphed over a threatening monster and lived to tell the tale.

But her story doesn't stop there - in some ways, a whole new life, overshadowed by trauma, has only just begun, Ohio State University graduate student Morgan Podraza posits in an article published in the journal Horror Studies.

Consider actor Jamie Lee Curtis' depiction of Laurie Strode in the Halloween film released in 2018, 40 years after her friends were murdered by Michael Myers on Halloween night. In that original film, she survived his attacks by wielding a knitting needle, a coat hanger and a knife that he dropped.

The grownup Strode lives an isolated life in a fortress in the woods, always on the lookout for the looming threat of Myers' return. Earlier in her adult life, viewers learn, her paranoia had rendered her an unfit mother in the eyes of authorities and her daughter was taken away.

In the article, Podraza, a PhD student in English, examines the representation of Strode's trauma in the 2018 Halloween sequel to the 1978 original, and how the depiction of her struggle after survival - how she has been vilified and dismissed, but ultimately proven right - might offer trauma survivors the chance to see a bit of themselves on the big screen.

"The way this film specifically deals with cycles of trauma and their connection to the experiences of survivors was really important to me because I think it is indicative of how we talk about trauma and survivors of trauma even today, and ways that people are spoken about negatively - their trauma is not acknowledged or they're not given an opportunity for healing," Podraza said.

"We can use the final girl trope now to reimagine spaces for healing or futures for people with trauma. A survivor's future will always include memories of that trauma, and it's important to acknowledge that trauma exists and continues to affect the reality of people who experience it.

"They deserve happy, healthy futures, too. People don't have to only be defined by the negative parts of this experience."

Podraza's scholarship centers on comics and animated film, but as a life-long fan of horror movies, she saw an opportunity to tie her interest in women-centered narratives and narratives of trauma to a favorite genre after the 2018 sequel release, which coincided with the #metoo movement.

When the sequel came out, Curtis herself called attention to the intersection of fiction and reality, telling Variety that she thought women battling their own trauma would be able to relate to Strode's desperate attempts to convince skeptics that Michael Myers was still a threat: "It feels like a confluence of that frustration and that rise of empowerment has come together in this movie in a beautiful way." Those promotional interviews resonated with Podraza.

"The scholarship hasn't looked beyond the final girl's survival and triumph. The final girl context has always been that she survived and that's enough. Or she killed the monster and that's enough. That's fine, but that's not how people's experiences work," she said. "Trauma is about the effects after the event is over."

The final girl trope was defined by scholar Carol Clover in the 1992 book Men, Women, and Chain Saws: Gender in the Modern Horror Film. The Laurie Strode character was central to Clover's definition of the trope, and while she emphasized that trauma helped characterize the final girl, the analysis stopped short of examining its effects.

Podraza cites scholarship in her article noting that survival of trauma itself is a crisis, that moving forward with life after a traumatizing event is also traumatic. The Laurie Strode character shows how this might look: Her obsession with protecting herself and others is tethered to her survival, and her outlook on life - a life saved by her own hand - remains grim because she's convinced she is subject to a continuing threat.

An analysis like this isn't intended to detract from the thrill of watching horror and slasher films, said Podraza, who advises her students to consume media for enjoyment first, and then re-watch or re-read the material with an eye toward asking critical questions.

"It's perfectly fine to just enjoy media, but it's always important to be aware of how media is framing experiences, especially experiences of people who are marginalized in any way. Survivors of trauma often are marginalized," she said. "The danger is to absorb media and never ask questions about it - that means you're not aware of how it's structuring your own behaviors and habits."

The franchise is slated to continue with the release of Halloween Kills in October and, in 2022, Halloween Ends. Based on the closing scene of the 2018 sequel, of Strode's granddaughter holding a bloody knife that she used to defend herself, Podraza sees potential for a depiction of intergenerational trauma.

"The structure of the franchise implies the cycle will just continue," she said, "and I am interested in how these concepts will perpetuate."

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Contact: Morgan Podraza, podraza.8@buckeyemail.osu.edu

Written by Emily Caldwell, Caldwell.151@osu.edu

 

Natural gas pipeline density higher overall in more vulnerable US counties

NORTH CAROLINA STATE UNIVERSITY

Research News

 

An analysis led by North Carolina State University researchers found counties with more socially vulnerable populations had a higher density of natural gas pipelines overall.

The findings suggest counties that are more socially vulnerable are also at greater risk of facing water and air pollution, public health and safety issues, and other negative impacts associated with the pipelines.

"We know that the network, as it stands today, is already distributed in such a way that any negative impacts fall disproportionately on vulnerable communities," said the study's lead author, Ryan Emanuel, a professor of forestry and environmental resources at NC State. "Right now, when regulators evaluate the social impacts of these projects, they are treated in isolation, and not as part of a massive network that affects more than 70 percent of all the counties in the U.S."

In the analysis, researchers used a measure of social vulnerability created in 2018 by the U.S. Centers for Disease Control and Prevention to assess 3,142 U.S. counties. The index combines information on household composition, age, disability status, race or ethnicity, language, and other factors to quantify a county's ability to bounce back from a disaster.

Then, using data from the U.S. Energy Information Administration, researchers evaluated how the approximately 229,000 miles of pipeline network in the United States mapped on top of counties, stratified by their social vulnerability scores.

"We studied the gas gathering and transmission pipelines, which are the really large and high-pressure pipelines that are meant to transport natural gas across regions or the country," Emanuel said. "We know that every year, there are explosions on transmission pipelines, and we have records for those accidents above a certain size. There are also air quality impacts at compressor stations that power them, and environmental damages that occur during construction."

For the 2,261 counties with pipelines in them - about 72 percent of U.S. counties - researchers found a correlation between counties with higher scores of social vulnerability, and the density of pipeline infrastructure.

"In general, the denser the pipeline network, the higher the social vulnerability score," said study co-author Louie Rivers III, associate professor of forestry and environmental resources at NC State. "The indication is the most vulnerable populations are also vulnerable to exploitation in terms of what people do with the land near them."

For planning the path of future projects, researchers say more nuance is needed in the regulatory process to evaluate communities. While population density is used as a factor used by regulators in assessing the severity of negative impacts of pipelines, density alone could overlook ways in which rural communities may be more vulnerable.

"When you evaluate the pipeline project for a rural area, you can't just assume that the concerns of a rural community are just going to be low-density versions of urban concerns," Emanuel said. "Rural issues are not less intense versions of urban issues. We also know from past research that these projects can have a destabilizing influence on rural communities."

Researchers also highlighted impacts of pipeline infrastructure on Indigenous communities in the U.S. They noted the Dakota Access, Keystone XL, Trans Mountain expansion and Enbridge Line 3 pipelines cross, or are proposed to cross, Indigenous territories in the U.S. and Canada. This raises concerns for communities about not only pollution or risks for health, but also for cultural harm to places with religious, historical or cultural significance.

The researchers pointed to the need to improve environmental assessments of potential pipeline infrastructure on vulnerable populations to prevent these networks from disproportionately impacting socially vulnerable people. They also called for better inclusion of community perspectives into decision-making.

"We need the same level of rigor applied to the issue of environmental justice in environmental impact statements as we see for other sections, such as water and air quality," Rivers said.

And while the existing infrastructure may have been built before federal policies were enacted to address environmental justice and antidiscrimination, researchers said federal regulators specifically need to assess the location of infrastructure networks as a whole in future planning to avoid reinforcing historic oppressive practices.

They also suggested assessing the cumulative impacts of all nearby infrastructure on factors such as air quality, noise and explosion risks.

"We need a comprehensive approach to environmental justice analyses that considers the larger network of infrastructure in which individual projects exist," Emanuel said.

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The study, "Natural Gas Gathering and Transmission Pipelines and Social Vulnerability in the United States," was published open access in the journal GeoHealth. The paper was co-authored by Martina Angela Caretta of Lund University and Pavithra Vasudevan at the University of Texas at Austin.

Note to editors: The abstract follows.

"Natural Gas Gathering and Transmission Pipelines and Social Vulnerability in the United States."

Authors: Ryan E. Emanuel, Martina Angela Caretta, Louie Rivers III and Pavithra Vasudevan.

DOI: 10.1029/2021GH000442

Published online in GeoHealth May 18, 2021.

Abstract: Midstream oil and gas infrastructure comprises vast networks of gathering and transmission pipelines that connect upstream extraction to downstream consumption. In the United States (US), public policies and corporate decisions have prompted a wave of proposals for new gathering and transmission pipelines in recent years, raising the question: Who bears the burdens associated with existing pipeline infrastructure in the US? With this in mind, we examined the density of natural gas gathering and transmission pipelines in the US together with county-level data on social vulnerability. For the 2,261 US counties containing natural gas pipelines, we found a positive correlation between county-level pipeline density and an index of social vulnerability. In general, counties with more socially vulnerable populations have significantly higher pipeline densities than counties with less socially vulnerable populations. In particular, counties in the top quartile of social vulnerability tend to have pipeline densities that are much higher than pipeline densities for counties in the bottom quartile of social vulnerability. The difference grows larger for counties at the upper extremes of pipeline density within each group. We discuss some of the implications for Indigenous communities and others affected by recent expansions of oil and gas infrastructure. We offer recommendations aimed at improving ways in which decision-makers identify and address the societal impacts and environmental justice implications of midstream pipeline infrastructure.

Scientists overhear two atoms chatting

DELFT UNIVERSITY OF TECHNOLOGY

Research News

 

IMAGE: ARTIST'S IMPRESSION OF THE EXPERIMENT, WHERE AN ELECTRIC PULSE IS APPLIED TO A TITANIUM ATOM. AS A RESULT, ITS MAGNETIC MOMENT SUDDENLY FLIPS AROUND. A NEIGHBOURING TITANIUM ATOM (RIGHT) REACTS... view more 

CREDIT: TU DELFT/SCIXEL

How materials behave depends on the interactions between countless atoms. You could see this as a giant group chat in which atoms are continuously exchanging quantum information. Researchers from Delft University of Technology in collaboration with RWTH Aachen University and the Research Center Jülich have now been able to intercept a chat between two atoms. They present their findings in Science on 28 May.

Atoms, of course, don't really talk. But they can feel each other. This is particularly the case for magnetic atoms. "Each atom carries a small magnetic moment called spin. These spins influence each other, like compass needles do when you bring them close together. If you give one of them a push, they will start moving together in a very specific way," explains Sander Otte, leader of the team that performed the research. "But according to the laws of quantum mechanics, each spin can be simultaneously point in various directions, forming a superposition. This means that actual transfer of quantum information takes place between the atoms, like some sort of conversation."

Sharp needle

On a large scale, this kind of exchange of information between atoms can lead to fascinating phenomena. A classic example is superconductivity: the effect where some materials lose all electrical resistivity below a critical temperature. While well understood for the simplest cases, nobody knows exactly how this effect comes about in many complex materials. But it's certain that magnetic quantum interactions play a key role. For the purpose of trying to explaining phenomena like this, scientists are very interested in being able to intercept these exchanges; to overhear the conversations between atoms.

In Otte's team they go about this rather directly: they literally put two atoms next to each other to see what happens. This is possible by virtue of a scanning tunneling microscope: a device in which a sharp needle can probe atoms one-by-one and can even rearrange them. The researchers used this device to place two titanium atoms at a distance of just over one nanometer - one millionth of a millimeter - apart. At that distance, the atoms are just able to feel each other's spin. If you would now twist one of the two spins, the conversation would start by itself.

Usually, this twist is performed by sending very precise radio signals to the atoms. This so-called spin resonance technique - which is quite reminiscent of the working principle of an MRI scanner found in hospitals - is used successfully in research on quantum bits. This tool is also available to the Delft team, but it has a disadvantage. "It is simply too slow," says PhD student Lukas Veldman, lead author on the Science publication. "You have barely started twisting the one spin before the other starts to rotate along. This way you can never investigate what happens upon placing the two spins in opposite directions."

Unorthodox approach

So the researchers tried something unorthodox: they rapidly inverted the spin of one of the two atoms with a sudden burst of electric current. To their surprise, this drastic approach resulted in a beautiful quantum interaction, exactly by the book. During the pulse, electrons collide with the atom, causing its spin to rotate. Otte: "But we always assumed that during this process, the delicate quantum information - the so-called coherence - was lost. After all, the electrons are incoherent: the history of each electron prior to the collision is slightly different and this chaos is transferred to the atom's spin, destroying any coherence."

The fact that this now seems not to be true was cause for some debate. Apparently, each random electron, regardless of its past, can initiate a coherent superposition: a specific combination of elementary quantum states which is fully known and which forms the basis for almost any form of quantum technology.

Perfect superposition

"The crux is that it depends on the question you ask," argues Markus Ternes, co-author from the RWTH Aachen University and the Research Center Jülich. "The electron inverts the spin of one atom causing it to point, say, to the left. You could view this as a measurement, erasing all quantum memory. But from the point of view of the combined system comprising both atoms, the resulting situation is not so mundane at all. For the two atoms together, the new state constitutes a perfect superposition, enabling the exchange of information between them. Crucially for this to happen is that both spins become entangled: a peculiar quantum state in which they share more information about each other than classically possible."

The discovery can be of importance to research on quantum bits. Perhaps also in that research you could get away with being slightly less careful when initializing quantum states. But for Otte and his team it is mostly the starting point of even more beautiful experiments. Veldman: "here we used two atoms, but what happens when you use three? Or ten, or a thousand? Nobody can predict that, as computing power falls short for such numbers. Perhaps one day we will be able to listen to quantum conversations that nobody could ever hear before."

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Jebel Sahaba: A succession of violence rather than a prehistoric war

CNRS

Research News

 

IMAGE: PROJECTILE IMPACT PUNCTURE WITH AN EMBEDDED LITHIC FRAGMENT IN THE POSTERIOR SURFACE OF THE LEFT HIP BONE OF INDIVIDUAL JS 21. view more 

CREDIT: © ISABELLE CREVECOEUR/MARIE-HÉLÈNE DIAS-MEIRINHO

Since its discovery in the 1960s, the Jebel Sahaba cemetery (Nile Valley, Sudan), 13 millennia old, was considered to be one of the oldest testimonies to prehistoric warfare. However, scientists from the CNRS and the University of Toulouse - Jean Jaurès (1) have re-analysed the bones preserved in the British Museum (London) and re-evaluated their archaeological context. The results, published in Scientific Reports on May 27, 2021, show that it was not a single armed conflict but rather a succession of violent episodes, probably exacerbated by climate change.

Many individuals buried at Jebel Sahaba bear injuries, half ot them caused by projectiles, the points of which were found in the bones or the fill where the body was located. The interpretation as evidence of mass death due to a single armed conflict, however, remained debated until a team of anthropologists, prehistorians and geochemists undertook a new study of the thousands of bones, about a hundred associated lithic pieces and the entire burial complex (now submerged by Lake Aswan) from 2013 to 2019.

The bones of 61 individuals were re-examined, including microscopic analysis, in order to distinguish traces of injury from damage produced after burial. About a hundred new lesions, both healed and unhealed, were identified, some with previously unrecognised lithic flakes still embedded in the bones. In addition to the 20 individuals already identified, 21 other skeletons have lesions, almost all suggestive of interpersonal violence, such as traces of projectile impact or fractures. In addition, 16 individuals have both healed and unhealed injuries, suggesting repeated episodes of violence over the course of a person's life rather than a single conflict. This hypothesis is supported by the fact that some skeletons appear to have been disturbed by later burials. Surprisingly, men, women and children seem to have been treated indiscriminately in terms of the number and type of injuries or the projectiles direction (2).

These new data also reveal that the majority of lesions were produced by composite projectiles, throwing weapons (arrows or spears) composed of several sharp lithic pieces, some of which are laterally embedded. The presence of variously sharpened points, with variations in the orientation of the cutting edge, suggests that the intended purpose was to lacerate and bleed the victim.

These new results reject the hypothesis of a disaster cemetery linked to a single war. Instead, this site indicates a succession of limited raids or ambushes against these hunter-fisher-gatherers, at a time of major climatic variations (end of the last ice age and beginning of the African humid period). The concentration of archaeological sites of different cultures in such a limited area of the Nile Valley at this time suggests that this region must have been a refuge area for human populations subject to these climatic fluctuations. Competition for resources is therefore probably one of the causes of the conflicts witnessed in the Jebel Sahaba cemetery. This analysis, which changes the history of violence in prehistory, invites us to reconsider other sites from the same period.

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Notes

(1) Working in the laboratories : « De la Préhistoire à l'actuel : culture, environnement et anthropologie » (CNRS/Université de Bordeaux/Ministère de la Culture), « Archéozoologie, archéobotanique : sociétés, pratiques et environnements » (CNRS/Museum national d'Histoire naturelle) and « Travaux et recherches archéologiques sur les cultures, les espaces et les sociétés » (CNRS/Université Toulouse - Jean Jaurès/Ministère de la Culture).

(2) Information from comparisons with experimental archaeological work on hunting techniques.

The robot smiled back

IMAGE: THE ROBOT SMILES BACK: EVA MIMICS HUMAN FACIAL EXPRESSIONS IN REAL-TIME FROM A LIVING STREAM CAMERA. THE ENTIRE SYSTEM IS LEARNED WITHOUT HUMAN LABELS. EVA LEARNS TWO ESSENTIAL CAPABILITIES: 1)... view more 

CREDIT: CREATIVE MACHINES LAB/COLUMBIA ENGINEERING

Columbia Engineering researchers use AI to teach robots to make appropriate reactive human facial expressions, an ability that could build trust between humans and their robotic co-workers and care-givers

COLUMBIA UNIVERSITY SCHOOL OF ENGINEERING AND APPLIED SCIENCE

Research News

 

New York, NY--May 27, 2021--While our facial expressions play a huge role in building trust, most robots still sport the blank and static visage of a professional poker player. With the increasing use of robots in locations where robots and humans need to work closely together, from nursing homes to warehouses and factories, the need for a more responsive, facially realistic robot is growing more urgent.

Long interested in the interactions between robots and humans, researchers in the Creative Machines Lab at Columbia Engineering have been working for five years to create EVA, a new autonomous robot with a soft and expressive face that responds to match the expressions of nearby humans. The research will be presented at the ICRA conference on May 30, 2021, and the robot blueprints are open-sourced on Hardware-X (April 2021).

"The idea for EVA took shape a few years ago, when my students and I began to notice that the robots in our lab were staring back at us through plastic, googly eyes," said Hod Lipson, James and Sally Scapa Professor of Innovation (Mechanical Engineering) and director of the Creative Machines Lab.

Lipson observed a similar trend in the grocery store, where he encountered restocking robots wearing name badges, and in one case, decked out in a cozy, hand-knit cap. "People seemed to be humanizing their robotic colleagues by giving them eyes, an identity, or a name," he said. "This made us wonder, if eyes and clothing work, why not make a robot that has a super-expressive and responsive human face?"

While this sounds simple, creating a convincing robotic face has been a formidable challenge for roboticists. For decades, robotic body parts have been made of metal or hard plastic, materials that were too stiff to flow and move the way human tissue does. Robotic hardware has been similarly crude and difficult to work with--circuits, sensors, and motors are heavy, power-intensive, and bulky.

VIDEO: https://youtu.be/1vBLI-q04kM
PROJECT WEBSITE: http://www.cs.columbia.edu/~bchen/aiface/

The first phase of the project began in Lipson's lab several years ago when undergraduate student Zanwar Faraj led a team of students in building the robot's physical "machinery." They constructed EVA as a disembodied bust that bears a strong resemblance to the silent but facially animated performers of the Blue Man Group. EVA can express the six basic emotions of anger, disgust, fear, joy, sadness, and surprise, as well as an array of more nuanced emotions, by using artificial "muscles" (i.e. cables and motors) that pull on specific points on EVA's face, mimicking the movements of the more than 42 tiny muscles attached at various points to the skin and bones of human faces.

"The greatest challenge in creating EVA was designing a system that was compact enough to fit inside the confines of a human skull while still being functional enough to produce a wide range of facial expressions," Faraj noted.

To overcome this challenge, the team relied heavily on 3D printing to manufacture parts with complex shapes that integrated seamlessly and efficiently with EVA's skull. After weeks of tugging cables to make EVA smile, frown, or look upset, the team noticed that EVA's blue, disembodied face could elicit emotional responses from their lab mates. "I was minding my own business one day when EVA suddenly gave me a big, friendly smile," Lipson recalled. "I knew it was purely mechanical, but I found myself reflexively smiling back."

Once the team was satisfied with EVA's "mechanics," they began to address the project's second major phase: programming the artificial intelligence that would guide EVA's facial movements. While lifelike animatronic robots have been in use at theme parks and in movie studios for years, Lipson's team made two technological advances. EVA uses deep learning artificial intelligence to "read" and then mirror the expressions on nearby human faces. And EVA's ability to mimic a wide range of different human facial expressions is learned by trial and error from watching videos of itself.

The most difficult human activities to automate involve non-repetitive physical movements that take place in complicated social settings. Boyuan Chen, Lipson's PhD student who led the software phase of the project, quickly realized that EVA's facial movements were too complex a process to be governed by pre-defined sets of rules. To tackle this challenge, Chen and a second team of students created EVA's brain using several Deep Learning neural networks. The robot's brain needed to master two capabilities: First, to learn to use its own complex system of mechanical muscles to generate any particular facial expression, and, second, to know which faces to make by "reading" the faces of humans.

To teach EVA what its own face looked like, Chen and team filmed hours of footage of EVA making a series of random faces. Then, like a human watching herself on Zoom, EVA's internal neural networks learned to pair muscle motion with the video footage of its own face. Now that EVA had a primitive sense of how its own face worked (known as a "self-image"), it used a second network to match its own self-image with the image of a human face captured on its video camera. After several refinements and iterations, EVA acquired the ability to read human face gestures from a camera, and to respond by mirroring that human's facial expression.

The researchers note that EVA is a laboratory experiment, and mimicry alone is still a far cry from the complex ways in which humans communicate using facial expressions. But such enabling technologies could someday have beneficial, real-world applications. For example, robots capable of responding to a wide variety of human body language would be useful in workplaces, hospitals, schools, and homes.

"There is a limit to how much we humans can engage emotionally with cloud-based chatbots or disembodied smart-home speakers," said Lipson. "Our brains seem to respond well to robots that have some kind of recognizable physical presence."

Added Chen, "Robots are intertwined in our lives in a growing number of ways, so building trust between humans and machines is increasingly important."

CAPTION

Data Collection Process: Eva is practicing random facial expressions by recording what it looks like from the front camera.

CREDIT

Creative Machines Lab/Columbia Engineering 

About the Study

The study is titled "Smile Like You Mean It: Driving Animatronic Robotic Face with Learned Models."

Authors are: Boyuan Chen, Yuhang Hu, Lianfeng Li, Sara Cummings, and Hod Lipson, Mechanical Engineering and Computer Science, Columbia Engineering.

The robot blueprint is titled "Facially Expressive Humanoid Robotic Face."

Authors of the robot blueprint paper are: Zanwar Faraj, Mert Selamet, Carlos Morales, Patricio Torres, Maimuna Hossain, Boyuan Chen, and Hod Lipson, Mechanical Engineering and Computer Science, Columbia Engineering.

The study was supported by National Science Foundation NRI 1925157 and DARPA MTO grant L2M Program HR0011-18-2-0020.

The authors declare no financial or other conflicts of interest.

LINKS:

Paper 1: https://arxiv.org/abs/2105.12724

Paper 2: https://www.sciencedirect.com/science/article/pii/S2468067220300262

VIDEO: https://youtu.be/1vBLI-q04kM

PROJECT WEBSITE: http://www.cs.columbia.edu/~bchen/aiface/

http://engineering.columbia.edu/
https://engineering.columbia.edu/faculty/hod-lipson
https://me.columbia.edu/
https://www.creativemachineslab.com/
http://www.cs.columbia.edu/~bchen/
https://www.zanwarfaraj.com/
https://www.cs.columbia.edu/

Columbia Engineering

Columbia Engineering, based in New York City, is one of the top engineering schools in the U.S. and one of the oldest in the nation. Also known as The Fu Foundation School of Engineering and Applied Science, the School expands knowledge and advances technology through the pioneering research of its more than 220 faculty, while educating undergraduate and graduate students in a collaborative environment to become leaders informed by a firm foundation in engineering. The School's faculty are at the center of the University's cross-disciplinary research, contributing to the Data Science Institute, Earth Institute, Zuckerman Mind Brain Behavior Institute, Precision Medicine Initiative, and the Columbia Nano Initiative. Guided by its strategic vision, "Columbia Engineering for Humanity," the School aims to translate ideas into innovations that foster a sustainable, healthy, secure, connected, and creative humanity.