The latest evidence that the ancient Indonesian “hobbit” was a distinct species of hominid, and not just a deformed pygmy, comes from the soles of its feet. Ever since researchers discovered the fossils of a three-foot-tall hominid with a chimpanzee-sized brain on the Indonesian island of Flores, debate has raged over how to interpret the bones. Now, a new study supports the theory that the hobbit, Homo floresiensis, was a species that split from our human lineage early in evolutionary history, and developed its strange shape in the isolation of the island. Other experts agree that evidence is accumulating that H. floresiensis was, in fact, a bona fide species.
In the new study, published in Nature, researchers found that the hobbit’s foot was surprisingly long in relation to the body, and that it had other ape-like features. The navicular bone, which helps form the arch in the modern foot, was especially primitive, more akin to one in great apes. Without a strong arch — that is, flat-footed — the hominid would have lacked the springlike action needed for efficient running. It could walk, but not run like humans. Weighing the new evidence, the research team led by William L. Jungers … concluded that “the foot of H. floresiensis exhibits a broad array of primitive features that are not seen in modern humans of any body size” [The New York Times].
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When the earliest human ancestors left the trees and struck out to make a new life for themselves on the ground, there was no going back, a new study suggests. Researchers examined the ankle bones of those early people and compared them to those of chimpanzees, and say that by 4 million years ago the proto-humans were no longer adapted for skillful tree climbing.
Researchers estimate that the chimpanzee and human lineages split about 5 million to 7 million years ago. Yet experts are divided about what happened next to the first hominins, as members of the human subfamily are called. One group argues–based on evidence that early members of the human line lived in woodland environments and had curved fingers and toes that were good for climbing–that the first hominins spent some time in the trees even as they adapted to their new ground-dwelling lifestyle [ScienceNOW Daily News]. The other faction believes that when humans began to walk upright they quickly lost their arboreal ways, and argues that their arms and legs were more human-like than ape-like.
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The oldest known fossil of a human child with a skull deformity has been discovered, suggesting that early humans did not kill or abandon their abnormal offspring, as has been commonly assumed. A research team reconstructed the 530,000-year-old skull, the first pieces of which were unearthed in Spain in 2001, and determined that the child likely suffered from craniosynostosis, a debilitating genetic disorder in which some pieces of the skull fuse too quickly, causing pressure to build in the brain [Wired] and interfering with brain development. The severity of the deformity is not clear, but researchers say the child probably had learning difficulties and other mental health issues, and certainly would have required extra care.
The child belonged to the species Homo heidelbergensis, who lived in Europe 800,000 years ago and may have been the direct ancestors of Neanderthals. Humans are thought to be unique in the way they care for sick individuals. Researchers call it conspecific care, but most laypeople would probably call it compassion. Other primates don’t display similar behavior, so we know humans evolved the ability at some point, even if scientists can’t quite pinpoint when. The work could mean that humans as far back as half a million years ago had differentiated from our primate ancestors [Wired].
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Isolated people living in the remote mountains of Cameroon have provided evidence that emotions expressed in Western music are universally recognizable, researchers say. In a new study, researchers found that members of the Mafa tribe could pick out happy, sad, and fearful tunes, despite having no exposure to Western music. Most likely the Mafa were picking up on the same “tone of voice” cues used in human speech, said study team member Stefan Koelsch…. “Western music mimics the emotional features of human speech, using the same melodic and rhythmic structures,” Koelsch said [National Geographic News].
Researchers say the Mafa’s ability to parse the emotions expressed in instrumental classical, jazz, and rock music adds evidence to the theory that music played some role in human evolution. Researchers have proposed numerous hypotheses about why humans make music, ranging from emotional communication to group solidarity. Other scientists, such as Harvard University linguist Steven Pinker, have countered that music is just “auditory cheesecake” with no real evolutionary significance. If music is the result of Darwinian selection, it’s likely that all members of the human species, regardless of their culture, will respond to it in similar ways [ScienceNOW Daily News].
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A clever and painstaking new analysis has revealed that the famous Homo erectus fossil known as Peking Man is 200,000 years older than previously thought. The fossil, discovered almost a century ago during excavations of the Zhoukoudian caves near Beijing, is now thought to be about 750,000 years old. The revised date could change the timeline and number of migrations of the Homo erectus species out of Africa and into Asia [LiveScience].
Homo erectus were the first hominids to leave the evolutionary cradle of Africa. The species had a distinctive barrel-shaped torso and stood [57 to 70 inches] tall, walking upright in a similar way to modern humans [Nature News]. Researchers had previously suggested that one wave of Homo erectus wayfarers migrated out of Africa between 2 million and 1.6 million years ago, settling Indonesia and southern Asia first before moving northward. But new fossil discoveries, coupled with the new dating of Peking Man, are forcing paleoanthropologists to rethink this scenario.
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A top official at Turkey’s science agency reportedly forced the editors of its science magazine to remove a cover story on the life and work of Charles Darwin in what appears to be a sign of the Turkish government’s official discomfort with the theory of evolution.
The article was stripped from the March issue of the widely read popular-science magazine Bilim ve Teknik (Science and Technology) just before it went to press. The magazine, which is published by Turkey’s research funding and science management organization, TÜBİTAK, also switched a planned cover picture of Darwin for an illustration relating to global warming [Nature News]. The editor of the magazine says she was removed from her post over the incident, but has declined to comment further as she’s still an employee of TUBITAK.
The March issue of the magazine, which was intented to celebrate Darwin’s 200th birthday, reached newsstands a week late and 16 pages short. Once the behind-the-scenes machinations became known, academics reacted with outrage. Turkish writer Ender Helvacıoğlu from Science and Future magazine called on the science community to react against this incident and pressure the government, who has the last word appointing the council’s scientific committee. “This intervention can’t be regarded as solely censorship. It connotes the states rejection of science” [Bianet], he wrote. Today a group of university professors were expected to gather at the science council’s headquarters to call for the resignation of the official who ordered the article removed.
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Researchers have peeked inside the brains of religious people responding to statements about God, and found that there’s no discrete part of the brain that handles religious beliefs–there’s no “God spot,” as other neuroscientists have suggested. The new study found that the neural activity in the subjects’ brains corresponded to brain networks known to have other, nonreligious functions…. “There is nothing segregated or conserved or special about religious beliefs, compared to other belief systems,” [lead researcher Jordan] Grafman said. The networks activated by religious beliefs overlap with those that mediate political beliefs and moral beliefs, he said [The New York Times].
The test subjects were read different types of statements dealing with God and religion while their brains were scanned with an fMRI machine, which measures blood flow to different parts of the brain. The scans showed that religious thoughts “light up” the areas of our brain which have evolved most recently, such as those involved in imagination, memory and “theory of mind” – the recognition that other people and living things can have their own thoughts and intentions [New Scientist].
Some researchers have hypothesized that religious beliefs are a byproduct of the neural networks used in theory of mind, suggesting that humans first evolved to imagine what other people are feeling, even people who aren’t present — and from there it was a short step to positing supernatural beings [Wired].
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About 10 percent of humanity is left-handed (including your humble blogger), but researchers have long wondered why the trait persists, since lefties seem to be at a disadvantage in the evolutionary race. Previous studies have found that lefties have shorter lifespans, shorter stature, and are more likely to be homosexual, three factors that make it more difficult for lefties to attract mates and reproduce. But a new study suggests that in addition to the vaunted creativity of southpaws, lefties may have simply had a tactical advantage throughout human evolution.
The study, which will be published in the Philosophical Transactions of the Royal Society B, surveys the existing literature and weighs the costs and the benefits of being left-handed. The study suggests that lefties have the element of surprise in one-on-one competitions, whether they’re serving tennis balls or attacking their enemies with knives. Study co-author Charlotte Faurie explains that because left-handers are less common, “their opponents will be surprised by the way they fight, and this will provide [lefties] an advantage,” she added. “It’s exactly the same in tennis or in boxing or in any sport where there is face-to-face opposition,” Faurie added [National Geographic News].
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Being treated unfairly in a game triggers the same facial expression as stomach-turning tastes and images, a new study has found, suggesting that the brain mechanism of disgust evolved to help humans avoid not just rotten food, but also immoral behavior.
“Our idea is that morality builds upon an old mental reflex, said study co-author Adam Anderson…. “The brain had already discovered a system for rejecting things that are bad for it. Then it co-opted this and attached it to conditions much removed from something tasting or smelling bad” [Wired News].
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The ancestors to modern humans really hit their stride 1.5 million years ago. Fossilized footprints found in Kenya were made by hominids that share a common foot anatomy and walking stride with modern humans, researchers say.
Scientists are almost certain that the 1.5-million-year-old prints belong to Homo erectus and that the individuals had heels, insteps and toes almost identical to those in humans, and they walked with a long stride similar to human locomotion…. The prints helped explain fossil and archaeological evidence that erectus had adapted the ability for long-distance walking and running [The New York Times]. There is evidence of a heavy landing on the heel with weight transferred along the outer edge of the foot, progressing to the ball of the foot and lifting off with the toes [BBC].
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Beauty is in the eye of the beholder, and whether that beholding eye belongs to a man or a woman may determine how beauty is processed and understood in the brain, according to a small, preliminary study. Researchers asked 10 men and 10 women to decide which paintings and photographs they found beautiful, while brain scans revealed which parts of their brains were active while they examined each image. The results suggested that while both sexes use parts of the brain associated with spacial awareness to process beauty, men use an area associated with big-picture thinking, while women also use a region linked to local details.
All the volunteers showed increased activity in the parietal lobe when gazing at a landscape or urban scene that they found beautiful, but men used only the right lobe, while women used the lobes on both the left and right sides of the brain. The researchers suggest that this is because women are contextualising the information and thinking more about the details of what they are seeing, assessing the position of objects according broad categories, such as “above” or “below”, or “left” or “right”. The men, they say, are focussing on the overall image using a more precise form of mental mapping [BBC News]. Study coauthor Camilo Cela-Conde hypothesizes that these differences may be linked to the different roles played by men and women throughout our evolution.
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After years of seemingly endless research, scientists have completed a first draft of the Neanderthal genome.
Nature reports that a team of scientists at the Max Planck Institute in Germany has sequenced 60 percent of the genome of a Neanderthal, the closest relative of modern humans. After analyzing more than a billion fragments of ancient DNA, the researchers constructed the genome mostly with DNA strands from a 38,000-year-old fossilized leg bone found in a cave in Croatia. They also used material from older remains, some up to 70,000 years old.
Neanderthals are thought to have been proficient at crafting basic tools and weapons, and died out shortly after Homo sapiens migrated to Europe, but the precise connection between the species has always been unclear. The Neanderthal genome sequence will clarify the evolutionary relationship between humans and Neanderthals as well as help identify those genetic changes that enabled modern humans to leave Africa and rapidly spread around the world, starting around 100,000 years ago [PhysOrg].
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Some religious leaders may take issue with Charles Darwin and what he represents, but the Vatican has announced that it is officially on board with evolution. A leading official declared yesterday that Darwin’s theory of evolution was compatible with Christian faith, and could even be traced to St Augustine and St Thomas Aquinas. “In fact, what we mean by evolution is the world as created by God,” said Archbishop Gianfranco Ravasi [Times Online]. Both St. Augustine and Thomas Aquinas recognized that life changes slowly over time, Ravasi said, and that was a step towards comprehending evolution.
The Vatican’s effort to show that science is not incompatible with religion will culminate in a conference on evolution next month, organized to mark the 150th anniversary of Darwin’s landmark publication, On the Origin of Species. The Vatican has backed away slightly from its original proposal to completely ban discussion of intelligent design at the event, which organizers called “poor theology and poor science”. [Instead,] Intelligent Design would be discussed at the fringes of the conference at the Pontifical Gregorian University, but merely as a “cultural phenomenon”, rather than a scientific or theological issue, organisers said [Times Online].
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Charles Darwin’s theory of evolution may have been shaped by his abhorrence of slavery as much as by his keen observations of Galapagos finches, a new book argues. Darwin’s Sacred Cause, by Adrian Desmond and James Moore, notes that slavery propaganda of the time often claimed that different races belonged to different species, a notion that Darwin’s work obliterated. The book suggests that Darwin’s unique approach to evolution – relating all races and species by “common descent” – could have been fostered by his anti-slavery beliefs [BBC News]. Published to coincide with Darwin’s 200th birthday and the 150th anniversary of his publication of On the Origin of Species this year, the book is likely to stir up a new debate over Darwin’s motives.
Many members of Darwin’s extended family were deeply devoted to the abolitionist cause, including his grandfather, Josiah Wedgwood, who founded a chinaware company and produced cameos distributed by anti-slavery campaigners; the medallions bore the legend “Am I Not a Man and a Brother?” Darwin’s mother and wife were Wedgwoods and anti-slavery was what Darwin called a “sacred cause”. He was taught to see the oppressed black as a “brother”. This explains why, when he went to Edinburgh University at 16, he could apprentice himself to a freed Guyanese slave to learn the art of bird preservation without thinking it [beneath his dignity] [Times Online]. Darwin later described that former slave as one of his intimate friends.
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Anthropologists have conducted a new analysis of skulls from the so-called “hobbit” fossils found in an Indonesian cave in 2003, and say their results add more evidence that the fossils come from a hitherto unknown race of tiny people. The researchers compared the hobbit skulls to those of modern humans and apes, as well as the fossil brain cases of early human ancestors. “The shape of the skull is consistent with what we would expect for a small archaic Homo,” said Karen Baab [National Geographic News], lead author of the new study.
When paleontologists unearthed a cluster of strange, hominid skeletons on the island of Flores, they had little idea that they were about to start a fierce debate that would divide the field of anthropology. But soon the researchers declared that the 18,000-year-old fossils came from people who were only three feet tall, and who were actually a different species of hominid, which researchers called Homo floresiensis. “These hobbits – hominids – appear to have survived when modern humans were all over the Earth at this time,” Baab said [The Guardian]. Since then, debate has raged over whether the hobbits were indeed an unknown species, or whether the individuals found in the cave were just modern humans with a disease that stunted their growth and gave them small brains, a condition called microcephaly.
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