The Science of Solidarity

By: Alexandria Addesso

To many Charles Darwin is the utmost authority when it comes to the study of evolution. Many people took his findings about the importance of competition and how it plays a role in evolution and ran with it. Even as far as applying it to society and thus creating social Darwinism. Anarcho-scientist Peter Kropotkin was inspired by the publication of On the Origin of Species to go and do his own observations of a multitude of species and seemed to come to the opposite conclusion of such Darwinism backers. He argued against claims that competition alone led to evolution or ‘survival of the fittest’, and insisted that mutual aid is a major factor of evolution. The following is an introductory excerpt from Kropotkin’s book Mutual Aid: A Factor of Evolution.

Two aspects of animal life impressed me most during the journeys which I made in my youth in Eastern Siberia and Northern Manchuria. One of them was the extreme severity of the struggle for existence which most species of animals have to carry on against an inclement Nature; the enormous destruction of life which periodically results from natural agencies; and the consequent paucity of life over the vast territory which fell under my observation. And the other was, that even in those few spots where animal life teemed in abundance, I failed to find – although I was eagerly looking for it – that bitter struggle for the means of existence, among animals belonging to the same species, which was considered by most Darwinists (though not always by Darwin himself) as the dominant characteristic of struggle for life, and the main factor of evolution.



Kropotkin chronicled his findings while observing a wide variety of insects, birds, sea-life, and different mammals including humans. When it came to who was fittest to survive and further their species, it was most often those who cooperated via forms of mutual aid and solidarity.

As soon as we study animals – not in laboratories and museums only, but in the forest and the prairie, in the steppe and the mountains – we at once perceive that though there is an immense amount of warfare and extermination going on amidst various species, and especially amidst various classes of animals, there is, at the same time, as much, or perhaps even more, of mutual support, mutual aid, and mutual defense amidst animals belonging to the same species or, at least, to the same society. Sociability is as much a law of nature as mutual struggle. Of course it would be extremely difficult to estimate, however roughly, the relative numerical importance of both these series of facts. But if we resort to an indirect test, and ask Nature: "Who are the fittest: those who are continually at war with each other, or those who support one another?" we at once see that those animals which acquire habits of mutual aid are undoubtedly the fittest. They have more chances to survive, and they attain, in their respective classes, the highest development of intelligence and bodily organization. If the numberless facts which can be brought forward to support this view are taken into account, we may safely say that mutual aid is as much a law of animal life as mutual struggle, but that, as a factor of evolution, it most probably has a far greater importance, inasmuch as it favours the development of such habits and characters as insure the maintenance and further development of the species, together with the greatest amount of welfare and enjoyment of life for the individual, with the least waste of energy.



Solidarity scientifically leads to the continuation of life. Through the solidarity of family units, as wells even sometimes larger communities, children are able to be raised and protected. Solidarity is also pivotal for any revolution, social movement, or major change to occur. The slogan “workers of the world unite,” first mentioned in the Communist Manifesto in 1848, called for solidarity among all proletariat (the lower/working class) regardless to nation or ethnicity. These were truly powerful words of unity for those across a particular class line against their oppressors that belonged to the bourgeoisie (the middle/capitalist class).

A major group that unified lower class people across ethnic and gender lines on U.S. soil in the aftermath of the Democratic Convention protests of 1968 was the original Rainbow Coalition. It was formed by the Illinois Chapter of The Black Panthers in Chicago and also included the Young Patriots (a group of white youth who had migrated from Appalachia to Chicago), the Young Lords (a group of Puerto Rican nationalist youth), disenfranchised jewish youth and members of the women’s movement. The Rainbow Coalition epitomized solidarity and intersectionality within the class struggle. Because of its diversity, the Rainbow Coalition was able to bring about treaties among violent rivaling gangs as well as fight against police brutality that did nothing but add to the wave of violence. With unity comes power, and this was highly threatening to both local and national government.



“It seems to me that a lot of the real intense government repression didn’t happen until the Black Panthers started building coalitions,” said Bobby Lee a Black Panthers member who helped organize the Rainbow Coalition along with Deputy Chairman of the Illinois Chapter Fred Hampton, in an interview with Chicago Area. “Once the party departed from the ‘hate whitey’ trip and got serious about building real politics, we were a threat—plain and simple. The FBI were always watching us. But the Rainbow Coalition was their worst nightmare.”

For major changes to occur, for the preservation of life, and to strive towards survival and thus evolution, solidarity is a major factor.

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Researchers Find the Existence of another Immune System in Humans

The good news is that doctors can determine which antigens a patient’s cancer cells release. By targeting sequestered antigens – the ones unknown to the immune system – doctors could greatly increase vaccines’ chances of success. NeuroscienceNews.com image is credited to United States Department of Health and Human Services and is for illustrative purposes only.

A groundbreaking new study reveals an unexpected interaction between men’s testes and the immune system. Additionally, the findings could help explain the development of certain autoimmune disorders and why some cancer vaccines are ineffective.

Unexpected connection likely sabotaging vaccines designed to treat cancer.
The University of Virginia, School of Medicine, has again shown that a part of the body thought to be disconnected from the immune system actually interacts with it, and that discovery helps explain cases of male infertility, certain autoimmune diseases and even the failure of cancer vaccines.

Scientists developing such vaccines may need to reconsider their work in light of the new findings or risk unintentionally sabotaging their own efforts. UVA’s Kenneth Tung, MD, said that many vaccines likely are failing simply because researchers are picking the wrong targets – targets that aren’t actually foreign to the immune system and thus won’t provoke the desired immune responses.

Overturning Orthodoxy
Tung, of UVA’s Beirne B. Carter Center for Immunology Research, and a team of collaborators have discovered an unexpected interaction between men’s testes and the immune system. While science textbooks insist the testes are barricaded from the immune system by an impenetrable wall of cells, the researchers have determined there’s actually a very small door in that wall, a door that appears to open in only one direction.



The team discovered that the testes release some, but not all, of the antigens – substances that can spur an immune response – that are created during the production of sperm. Because the testes release these antigens naturally, the immune system ignores them. That’s a normal, healthy response, but it also may explain why cancer vaccines are failing. Cancer vaccines target antigens, so if vaccine developers rely on antigens that are ignored by the immune system, the vaccine won’t work.

“In essence, we believe the testes antigens can be divided into those which are sequestered [behind the barrier] and those that are not,” Tung said. “Antigens which are not sequestered would not be very good cancer vaccine candidates.”

The good news is that doctors can determine which antigens a patient’s cancer cells release. By targeting sequestered antigens – the ones unknown to the immune system – doctors could greatly increase vaccines’ chances of success.



Treating Infertility
The finding also may prove important for couples seeking to have children. Up to 12 percent of men who suffer from infertility have an autoimmune response to their own reproductive cells. That means their immune systems are attacking their sperm, essentially. Tung and his collaborators shed light on what may be happening, showing that a particular step during the creation of sperm is responsible for determining whether the sperm antigens will spark an immune response. Cells called “regulatory T cells” then help control the immune system’s response to the non-sequestered antigens. In men who are infertile because of an autoimmune disorder, something is going wrong with the process, leading the immune system to attack when it shouldn’t. With that knowledge, doctors may be able to develop new treatments for the autoimmune disorders and the resulting infertility.

Rethinking the Immune System
The discovery of the unknown immune interaction comes less than two years after UVA’s Jonathan Kipnis and Antoine Louveau rewrote textbooks when they discovered that the brain has a direct connection to the immune system, a connection long thought not to exist. That discovery could have profound effects in the quest to defeat diseases ranging from Alzheimer’s to multiple sclerosis.
Source: University of Virginia Health System.

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How humans bond: The Brain Chemistry Revealed

In a new study researches found for the first time that dopamine is involved in human bonding bringing the brain’s reward into understanding of how we form human attachments.

In new research published Monday in the journal Proceedings of the National Academy of Sciences, Northeastern University psychology professor Lisa Feldman Barrett found, for the first time, that the neurotransmitter dopamine is involved in human bonding, bringing the brain's reward system into our understanding of how we form human attachments. The results, based on a study with 19 mother-infant pairs, have important implications for therapies addressing postpartum depression as well as disorders of the dopamine system such as Parkinson's disease, addiction, and social dysfunction.



"The infant brain is very different from the mature adult brain -- it is not fully formed," says Barrett, University Distinguished Professor of Psychology and author of the forthcoming book How Emotions Are Made: The Secret Life of the Brain. "Infants are completely dependent on their caregivers. Whether they get enough to eat, the right kind of nutrients, whether they're kept warm or cool enough, whether they're hugged enough and get enough social attention, all these things are important to normal brain development. Our study shows clearly that a biological process in one person's brain, the mother's, is linked to behavior that gives the child the social input that will help wire his or her brain normally. That means parents' ability to keep their infants cared for leads to optimal brain development, which over the years results in better adult health and greater productivity."

To conduct the study, the researchers turned to a novel technology: a machine capable of performing two types of brain scans simultaneously -- functional magnetic resonance imaging, or fMRI, and positron emission tomography, or PET.

fMRI looks at the brain in slices, front to back, like a loaf of bread, and tracks blood flow to its various parts. It is especially useful in revealing which neurons are firing frequently as well as how different brain regions connect in networks. PET uses a small amount of radioactive chemical plus dye (called a tracer) injected into the bloodstream along with a camera and a computer to produce multidimensional images to show the distribution of a specific neurotransmitter, such as dopamine or opioids.



Barrett's team focused on the neurotransmitter dopamine, a chemical that acts in various brain systems to spark the motivation necessary to work for a reward. They tied the mothers' level of dopamine to her degree of synchrony with her infant as well as to the strength of the connection within a brain network called the medial amygdala network that, within the social realm, supports social affiliation.

"We found that social affiliation is a potent stimulator of dopamine," says Barrett. "This link implies that strong social relationships have the potential to improve your outcome if you have a disease, such as depression, where dopamine is compromised. We already know that people deal with illness better when they have a strong social network. What our study suggests is that caring for others, not just receiving caring, may have the ability to increase your dopamine levels."



Before performing the scans, the researchers videotaped the mothers at home interacting with their babies and applied measurements to the behaviors of both to ascertain their degree of synchrony. They also videotaped the infants playing on their own.

Once in the brain scanner, each mother viewed footage of her own baby at solitary play as well as an unfamiliar baby at play while the researchers measured dopamine levels, with PET, and tracked the strength of the medial amygdala network, with fMRI.

The mothers who were more synchronous with their own infants showed both an increased dopamine response when viewing their child at play and stronger connectivity within the medial amygdala network. "Animal studies have shown the role of dopamine in bonding but this was the first scientific evidence that it is involved in human bonding," says Barrett. "That suggests that other animal research in this area could be directly applied to humans as well."

The findings, says Barrett, are "cautionary." "They have the potential to reveal how the social environment impacts the developing brain," she says. "People's future health, mental and physical, is affected by the kind of care they receive when they are babies. If we want to invest wisely in the health of our country, we should concentrate on infants and children, eradicating the adverse conditions that interfere with brain development."
Source: Materials provided by Northeastern University, original written by Thea Singer.

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The incredible Artificial Intelligence Systems: They may See the world as Humans Do

A Northwestern University team developed a new computational model that performs at human levels on a standard intelligence test. This work is an important step toward making artificial intelligence systems that see and understand the world as humans do.

"The model performs in the 75th percentile for American adults, making it better than average," said Northwestern Engineering's Ken Forbus. "The problems that are hard for people are also hard for the model, providing additional evidence that its operation is capturing some important properties of human cognition."



The new computational model is built on CogSketch, an artificial intelligence platform previously developed in Forbus' laboratory. The platform has the ability to solve visual problems and understand sketches in order to give immediate, interactive feedback. CogSketch also incorporates a computational model of analogy, based on Northwestern psychology professor Dedre Gentner's structure-mapping theory. (Gentner received the 2016 David E. Rumelhart Prize for her work on this theory.)

Forbus, Walter P. Murphy Professor of Electrical Engineering and Computer Science at Northwestern's McCormick School of Engineering, developed the model with Andrew Lovett, a former Northwestern postdoctoral researcher in psychology. Their research was published online this month in the journal Psychological Review.

The ability to solve complex visual problems is one of the hallmarks of human intelligence. Developing artificial intelligence systems that have this ability not only provides new evidence for the importance of symbolic representations and analogy in visual reasoning, but it could potentially shrink the gap between computer and human cognition.

While Forbus and Lovett's system can be used to model general visual problem-solving phenomena, they specifically tested it on Raven's Progressive Matrices, a nonverbal standardized test that measures abstract reasoning. All of the test's problems consist of a matrix with one image missing. The test taker is given six to eight choices with which to best complete the matrix. Forbus and Lovett's computational model performed better than the average American.



"The Raven's test is the best existing predictor of what psychologists call 'fluid intelligence, or the general ability to think abstractly, reason, identify patterns, solve problems, and discern relationships,'" said Lovett, now a researcher at the US Naval Research Laboratory. "Our results suggest that the ability to flexibly use relational representations, comparing and reinterpreting them, is important for fluid intelligence."

The ability to use and understand sophisticated relational representations is a key to higher-order cognition. Relational representations connect entities and ideas such as "the clock is above the door" or "pressure differences cause water to flow." These types of comparisons are crucial for making and understanding analogies, which humans use to solve problems, weigh moral dilemmas, and describe the world around them.

"Most artificial intelligence research today concerning vision focuses on recognition, or labeling what is in a scene rather than reasoning about it," Forbus said. "But recognition is only useful if it supports subsequent reasoning. Our research provides an important step toward understanding visual reasoning more broadly."

Source: Amanda Morris - Journal reference: Psychological Review

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What Did Neanderthals Leave to Modern Humans? Some Surprises

At Vanderbilt University, John Anthony Capra, an evolutionary genomics professor, has been combining high-powered computation and a medical records databank to learn what a Neanderthal heritage — even a fractional one — might mean for people today.
We spoke for two hours when Dr. Capra, 35, recently passed through New York City. An edited and condensed version of the conversation follows.

-Let’s begin with an indiscreet question. How did contemporary people come to have Neanderthal DNA on their genomes?

-He replied: “we hypothesize that roughly 50,000 years ago, when the ancestors of modern humans migrated out of Africa and into Eurasia, they encountered Neanderthals. Mating must have occurred then, and later.”

One reason we deduce this is because the descendants of those who remained in Africa — present day Africans — don’t have Neanderthal DNA.

What does that mean for people who have it?
At my lab, we’ve been doing genetic testing on the blood samples of 28,000 patients at Vanderbilt and eight other medical centers across the country. Computers help us pinpoint where on the human genome this Neanderthal DNA is, and we run that against information from the patients’ anonymized medical records. We’re looking for associations.



What we’ve been finding is that Neanderthal DNA has a subtle influence on risk for disease. It affects our immune system and how we respond to different immune challenges. It affects our skin. You’re slightly more prone to a condition where you can get scaly lesions after extreme sun exposure. There’s an increased risk for blood clots and tobacco addiction.

To our surprise, it appears that some Neanderthal DNA can increase the risk for depression; however, there are other Neanderthal bits that decrease the risk. Roughly 1 to 2 percent of one’s risk for depression is determined by Neanderthal DNA. It all depends on where on the genome it’s located.

Was there ever an upside to having Neanderthal DNA?
It probably helped our ancestors survive in prehistoric Europe. When humans migrated into Eurasia, they encountered unfamiliar hazards and pathogens. By mating with Neanderthals, they gave their offspring needed defenses and immunities.



That trait for blood clotting helped wounds close up quickly. In the modern world, however, this trait means greater risk for stroke and pregnancy complications. What helped us then doesn’t necessarily now.

Did you say earlier that Neanderthal DNA increases susceptibility to nicotine addiction? Yes. Neanderthal DNA can mean you’re more likely to get hooked on nicotine, even though there were no tobacco plants in archaic Europe.

We think this might be because there’s a bit of Neanderthal DNA right next to a human gene that’s a neurotransmitter implicated in a generalized risk for addiction. In this case and probably others, we think the Neanderthal bits on the genome may serve as switches that turn human genes on or off.

Aside from the Neanderthals, do we know if our ancestors mated with other hominids? We think they did. Sometimes when we’re examining genomes, we can see the genetic afterimages of hominids, which haven’t even been identified yet.




MORE REPORTING ON HUMAN ORIGINS
A few years ago, the Swedish geneticist Svante Pääbo received an unusual fossilized bone fragment from Siberia. He extracted the DNA, sequenced it and realized it was neither human nor Neanderthal. What Pääbo found was a previously unknown hominid he named Denisovan, after the cave where it had been discovered. It turned out that Denisovan DNA can be found on the genomes of modern Southeast Asians and New Guineans.

Have you long been interested in genetics?
Growing up, I was very interested in history, but I also loved computers. I ended up majoring in computer science at college and going to graduate school in it; however, during my first year in graduate school, I realized I wasn’t very motivated by the problems that computer scientists worked on.

Fortunately, around that time — the early 2000s — it was becoming clear that people with computational skills could have a big impact in biology and genetics. The human genome had just been mapped. What an accomplishment! We now had the code to what makes you, you, and me, me. I wanted to be part of that kind of work.

So I switched over to biology. And it was there that I heard about a new field where you used computation and genetics research to look back in time — evolutionary genomics.



There may be no written records from prehistory, but genomes are a living record. If we can find ways to read them, we can discover things we couldn’t know any other way.

Not long ago, the two top editors of The New England Journal of Medicine published an editorial questioning “data sharing,” a common practice where scientists recycle raw data other researchers have collected for their own studies. They labeled some of the recycling researchers, “data parasites.” How did you feel when you read that?
I was upset. The data sets we used were not originally collected to specifically study Neanderthal DNA in modern humans. Thousands of patients at Vanderbilt consented to have their blood and their medical records deposited in a “biobank” to find genetic diseases.

Three years ago, when I set up my lab at Vanderbilt, I saw the potential of the biobank for studying both genetic diseases and human evolution. I wrote special computer programs so that we could mine existing data for these purposes.

That’s not being a “parasite.” That’s moving knowledge forward. I suspect that most of the patients who contributed their information are pleased to see it used in a wider way.

What has been the response to your Neanderthal research since you published it last year in the journal Science?

Some of it’s very touching. People are interested in learning about where they came from. Some of it is a little silly. “I have a lot of hair on my legs — is that from Neanderthals?”

But I received racist inquiries, too. I got calls from all over the world from people who thought that since Africans didn’t interbreed with Neanderthals, this somehow justified their ideas of white superiority.

It was illogical. Actually, Neanderthal DNA is mostly bad for us — though that didn’t bother them.

As you do your studies, do you ever wonder about what the lives of the Neanderthals were like?
It’s hard not to. Genetics has taught us a tremendous amount about that, and there’s a lot of evidence that they were much more human than apelike.

They’ve gotten a bad rap. We tend to think of them as dumb and brutish. There’s no reason to believe that. Maybe those of us of European heritage should be thinking, “Let’s improve their standing in the popular imagination. They’re our ancestors, too.’”
Source: Claudia Dreifus

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Communal Living: Is This How Humans Are Meant To Live?

By: Alexandria Addesso

Often I go to sleep to the sound of laughter or music coming from the next room over and wake up to people talking, unfortunately for me sometimes quite loudly. I currently share a living space with over 20 other people, but I also share my meals with them, my work and my overall life. Unlike many other people in Western society and even the world, I live in an intentional community.

To some communal living may seem scary or completely repulsive, but is it how humans are meant to live? In the extremely individualistic culture of the United States communal living may seem unnatural but it is believed that early humans lived and hunted in herds. During the most recent Ice Age, about 20,000-10,000 years ago, the human herd may have looked very similar to the wolf packs of that time. Both hunted bison and other large animals and were most likely familial. Adult members of both species were protective of the young and good at interpreting the moods of others in the group, whether through facial expression or other forms of body language.



In modern society it is expected that once a person reaches adulthood they should strike out on their own and become independent, but humans are social creatures. We thrive in groups. Although in Western culture a child is expected to leave their family’s home once they have reached full maturity, many Eastern societies abhor this notion. Although not an intentional community, living with family is living communally. Especially if it is a large family.

“Some people thrive, but some people cannot live in community or with others and that’s why they leave,” said Catherine Morris, who has been living communally for the past 56 years.



Although some people thrive living in a communal setting, it is definitely not an easy task. So many different personalities from different cultures and backgrounds living under the same roof can definitely prove difficult and be a test in the virtue of patience. But the payoff is the lack of one of the most primal human fears, being alone. And furthermore dying alone.

When human beings can successfully work together much can be accomplished. Revolutions can be started, oppression can be defeated, much can be built and much needed change can be made. As technology is making it easier for people to connect, it is also pushing us farther and farther spatially apart. If people can successfully live together on one plot of land or under one roof, than maybe we could learn to live together successfully and peacefully on one planet. The burdensome workload of one becomes easier to carry when it becomes the cooperative workload of many.

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Computers have the ability to Reason Like Humans

Northwestern University's Ken Forbus is closing the gap between humans and machines.

Using cognitive science theories, Forbus and his collaborators have developed a model that could give computers the ability to reason more like humans and even make moral decisions. Called the structure-mapping engine (SME), the new model is capable of analogical problem solving, including capturing the way humans spontaneously use analogies between situations to solve moral dilemmas.



"In terms of thinking like humans, analogies are where it's at," said Forbus, Walter P. Murphy Professor of Electrical Engineering and Computer Science in Northwestern's McCormick School of Engineering. "Humans use relational statements fluidly to describe things, solve problems, indicate causality, and weigh moral dilemmas."

The theory underlying the model is psychologist Dedre Gentner's structure-mapping theory of analogy and similarity, which has been used to explain and predict many psychology phenomena.

Structure-mapping argues that analogy and similarity involve comparisons between relational representations, which connect entities and ideas, for example, that a clock is above a door or that pressure differences cause water to flow.

Analogies can be complex (electricity flows like water) or simple (his new cell phone is very similar to his old phone). Previous models of analogy, including prior versions of SME, have not been able to scale to the size of representations that people tend to use. Forbus's new version of SME can handle the size and complexity of relational representations that are needed for visual reasoning, cracking textbook problems, and solving moral dilemmas.

"Relational ability is the key to higher-order cognition," said Gentner, Alice Gabrielle Twight Professor in Northwestern's Weinberg College of Arts and Sciences. "Although we share this ability with a few other species, humans greatly exceed other species in ability to represent and reason with relations."

Supported by the Office of Naval Research, Defense Advanced Research Projects Agency, and Air Force Office of Scientific Research, Forbus and Gentner's research is described in the June 20 issue of the journal Cognitive Science. Andrew Lovett, a postdoctoral fellow in Gentner's laboratory, and Ronald Ferguson, a PhD graduate from Forbus's laboratory, also authored the paper.



Many artificial intelligence systems -- like Google's AlphaGo -- rely on deep learning, a process in which a computer learns examining massive amounts of data. By contrast, people -- and SME-based systems -- often learn successfully from far fewer examples. In moral decision-making, for example, a handful of stories suffices to enable an SME-based system to learn to make decisions as people do in psychological experiments.

"Given a new situation, the machine will try to retrieve one of its prior stories, looking for analogous sacred values, and decide accordingly," Forbus said.

SME has also been used to learn to solve physics problems from the Advanced Placement test, with a program being trained and tested by the Educational Testing Service. As further demonstration of the flexibility of SME, it also has been used to model multiple visual problem-solving tasks.

To encourage research on analogy, Forbus's team is releasing the SME source code and a 5,000-example corpus, which includes comparisons drawn from visual problem solving, textbook problem solving, and moral decision making.

The range of tasks successfully tackled by SME-based systems suggests that analogy might lead to a new technology for artificial intelligence systems as well as a deeper understanding of human cognition. For example, using analogy to build models by refining stories from multiple cultures that encode their moral beliefs could provide new tools for social science. Analogy-based artificial intelligence techniques could be valuable across a range of applications, including security, health care, and education.



"SME is already being used in educational software, providing feedback to students by comparing their work with a teacher's solution," Forbus said. But there is a vast untapped potential for building software tutors that use analogy to help students learn."

Source: Northwestern University

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Who are human's real ancestors?

Neanderthals became extinct about 40,000 years ago but contributed on average one to three percent to the genomes of present-day Eurasians. Researchers have now analyzed DNA from a 37,000 to 42,000-year-old human mandible from Oase Cave in Romania and have found that six to nine percent of this person's genome came from Neanderthals, more than any other human sequenced to date. Because large segments of this individual's chromosomes are of Neanderthal origin, a Neanderthal was among his ancestors as recently as four to six generations back in his family tree. This shows that some of the first modern humans that came to Europe mixed with the local Neanderthals.

All present-day humans who have their roots outside sub-Saharan Africa carry one to three percent of Neanderthal DNA in their genomes. Until now, researchers have thought it most likely that early humans coming from Africa mixed with Neanderthals in the Middle East around 50,000 to 60,000 years ago, before spreading into Asia, Europe and the rest of the world. However, radiocarbon dating of remains from sites across Europe suggests that modern humans and Neanderthals both lived in Europe for up to 5,000 years and that they may have interbred there, too.

In 2002, a 40,000-year-old jawbone was found by cavers in Oase Cave in south-western Romania and the site was subsequently studied by an international team led by the researchers of the Emil Racovita Institute of Speleology in Romania. Researchers from the Max Planck Institute for Evolutionary Anthropology (Germany), Harvard Medical School (USA), and the Key Laboratory of Vertebrate Evolution and Human Origins in Beijing (China) have now analyzed DNA from this fossil, which is one of the earliest modern-human remains found in Europe. They estimate that five to 11 percent of the genome preserved in the bone derives from a Neanderthal ancestor, including exceptionally large segments of some chromosomes. By estimating how lengths of DNA inherited from an ancestor shorten with each generation, the researchers estimated that the man had a Neanderthal ancestor in the previous four to six generations.

"The data from the jawbone imply that humans mixed with Neanderthals not just in the Middle East but in Europe as well" says Qiaomei Fu, one of the lead researchers of the study. "Interestingly, the Oase individual does not seem to have any direct descendants in Europe today," says David Reich from Harvard Medical School who coordinated the population genetic analyses of the study. "It may be that he was part of an early migration of modern humans to Europe that interacted closely with Neanderthals but eventually became extinct."

"It is such a lucky and unexpected thing to get DNA from a person who was so closely related to a Neanderthal" comments Svante Paabo from the Max Planck Institute for Evolutionary Anthropology who led the study. "I could hardly believe it when we first saw the results." "We hope that DNA from other human fossils that predate the extinction of Neanderthals will help reconstruct the interactions between Neanderthals and modern humans in even more detail," says Mateja Hajdinjak, another key researcher involved in the study.

"When we started the work on Oase site, everything was already pointing to an exceptional discovery," remembers Oana Moldovan, the Romanian researcher who initiated the systematic excavation of the cave in 2003. "But such discoveries require painstaking research to be confirmed," adds Silviu Constantin, her colleague who worked on dating of the site. "We have previously shown that Oase is indeed the oldest modern human in Europe known so far, and now this research confirms that the individual had a Neanderthal ancestor. What more could we wish for?"

Story Source:

The above post is reprinted from materials provided by Max-Planck-Gesellschaft. Note: Materials may be edited for content and length.

Journal Reference:

Qiaomei Fu, Mateja Hajdinjak, Oana Teodora Moldovan, Silviu Constantin, Swapan Mallick, Pontus Skoglund, Nick Patterson, Nadin Rohland, Iosif Lazaridis, Birgit Nickel, Bence Viola, Kay Prüfer, Matthias Meyer, Janet Kelso, David Reich, Svante Pääbo. An early modern human from Romania with a recent Neanderthal ancestor. Nature, 2015; DOI: 10.1038/nature14558

Photo: Credit: MPI f. Evolutionary Anthropology/ Paabo