Scientists build new ‘tree of life’ for placentals, visualize common ancestor
Scientists have reconstructed the common ancestor of placental mammals–an extremely diverse group including animals ranging from rodents to whales to humans–using the world’s largest dataset of both genetic and physical traits. (more…)
A Yale scientist and colleagues in Britain have found a highly unusual ancient marine fossil that retains soft body parts as well as its shell, including limbs, eyes, gills and alimentary system. The fossil represents a new species of ostracod, a tiny crustacean related to crabs, lobsters and shrimps.
“Fossil ostracods often provide evidence of the relative ages of the rocks in which they occur, but it is very difficult to determine their relationship to living forms because only the shell is normally preserved,” said Derek E. G. Briggs, director of Yale’s Peabody Museum of Natural History and a co-author of the research. “This 425-million-year-old new form is remarkable in preserving the limbs and other anatomical features as well.” (more…)
A decade ago, a British philosopher put forth the notion that the universe we live in might in fact be a computer simulation run by our descendants. While that seems far-fetched, perhaps even incomprehensible, a team of physicists at the University of Washington has come up with a potential test to see if the idea holds water.
The concept that current humanity could possibly be living in a computer simulation comes from a 2003 paper published in Philosophical Quarterly by Nick Bostrom, a philosophy professor at the University of Oxford. In the paper, he argued that at least one of three possibilities is true:
A Yale-led scientific team has produced the most comprehensive family tree for birds to date, connecting all living bird species — nearly 10,000 in total — and revealing surprising new details about their evolutionary history and its geographic context.
Analysis of the family tree shows when and where birds diversified — and that birds’ diversification rate has increased over the last 50 million years, challenging the conventional wisdom of biodiversity experts.
“It’s the first time that we have — for such a large group of species and with such a high degree of confidence — the full global picture of diversification in time and space,” said biologist Walter Jetz of Yale, lead author of the team’s research paper, published Oct. 31 online in the journal Nature. (more…)
Developing a shared sense of global community could help reduce major episodes of violence
In the tribal societies of the Amazon forest, violent conflict accounted for 30 percent of all deaths before contact with Europeans, according to a recent study by University of Missouri anthropologist Robert Walker. Understanding the reasons behind those altercations in the Amazon sheds light on the instinctual motivations that continue to drive human groups to violence, as well as the ways culture influences the intensity and frequency of violence.
“The same reasons – revenge, honor, territory and jealousy over women – that fueled deadly conflicts in the Amazon continue to drive violence in today’s world,” said Walker, lead author and assistant professor of anthropology in MU’s College of Arts and Science. “Humans’ evolutionary history of violent conflict among rival groups goes back to our primate ancestors. It takes a great deal of social training and institutional control to resist our instincts and solve disputes with words instead of weapons. Fortunately, people have developed ways to channel those instincts away from actual deadly conflict. For example, sports and video games often involve the same impulses to defeat a rival group.” (more…)
EAST LANSING, Mich. — Dividing tasks among different individuals is a more efficient way to get things done, whether you are an ant, a honeybee or a human.
A new study by researchers at Michigan State University’s BEACON Center for the Study of Evolution in Action suggests that this efficiency may also explain a key transition in evolutionary history, from single-celled to multi-celled organisms.
The results, which can be found in the current issue of the Proceedings of the National Academy of Sciences, demonstrate that the cost of switching between different tasks gives rise to the evolution of division of labor in digital organisms. In human economies, these costs could be the mental shift or the travel time required to change from activity to another. (more…)
A brain-development gene found exclusively in humans has an unusual evolutionary history and could contribute to what makes us distinctly human. Equally surprising, this is a partial gene created from an incomplete duplication of its “parent” gene in the prehistoric human genome.
Gene duplication is an important driving force in creating physical changes in living things during evolution, explained the researchers studying the SRGAP2 gene family. Drs. Megan Dennis and Xander Nuttle, in the Howard Hughes Medicine Institute research lab of Dr. Evan Eichler, University of Washington professor of genome sciences, co-authored the report on the findings. (more…)
*Discovery of partial foot skeleton could mean hominin species lived side by side*
A new fossil discovery from Eastern Africa called the Burtele foot indicates Australopithecus afarensis, an early relative of modern humans, may not have been the only hominin to walk the plains and woodlands of what is now the Afar region of Ethiopia some 3.4 million years ago.
Researchers openly have questioned whether Au. afarensis, the species to which the famous fossil “Lucy” belongs, was the only living hominin during the late Pliocene of Africa. Lucy’s bones provided evidence that she and perhaps other early hominins may have walked upright, but whether or not she was the sole hominin species in her particular geologic time scale has been the subject of much debate. (more…)
