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Categories: Anthropology: Early Humans, Paleontology: Early Mammals and Birds

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Did the first ancestors of whales pick up where the mosasaurs left off 66 million years ago, after the extinction of all the large predatory marine reptiles? A study has looked into the possible convergences in morphology and behavior that may exist between these two groups of large marine predatory animals.

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Scientists use genomic data to resolve the phylogeny of zygnematophyte algae and pinpoint several emergences of multicellularity in the closest known relatives of terrestrial plants.

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Approximately 13.5 million years ago, north-west Queensland was home to an unusual and particularly tiny species of crocodile and now scientists are unlocking its secrets.

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The modalities and date of emergence of bipedalism remain bitterly debated, in particular because of a small number of very old human fossils. Sahelanthropus tchadensis, discovered in 2001 in Chad, is considered to be the oldest representative of the humankind. The shape of its cranium suggests a bipedal station. The description of three limb bones of Sahelanthropus confirms habitual bipedalism, but not exclusively.

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Research has established that there are traces of Neandertal DNA in the genome of modern humans. Now an exploratory study that assessed the facial structure of prehistoric skulls is offering new insights, and supports the hypothesis that much of this interbreeding took place in the Near East -- the region ranging from North Africa to Iraq.

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To investigate whether paleoclimatic temperature shifts are correlated with body size changes, biologists decided to test this hypothesis using tetraodontiform fishes as a model group.

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A new study shows that 87 genes have been affected by deletions or short insertions during the course of the mammoth's evolution. The researchers note that their findings have implications for international efforts to resurrect extinct species, including the woolly mammoth.

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Researchers successfully captured CT images of an entire woolly mammoth tusk. Researchers were able to do a full scan of the tusk in its entirety -- or in toto -- using a newer clinical CT scanner. The new technology allows for large-scale imaging without having to do multiple partial scans.

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Did the 12th century B.C.E. -- a time when humans were forging great empires and developing new forms of written text -- coincide with an evolutionary reduction in brain size? Think again, says a team of researchers whose new paper refutes a hypothesis that's growing increasingly popular among the science community.

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New research provide evidence that the crustacean carapace, along with other plate-like structures in arthropods (crustaceans, insects, arachnids, and myriapods) all evolved from a lateral leg lobe in a common ancestor more than 500 million years ago. This work further supports their proposal for a new concept of how novel structures evolve -- one which suggests that they aren't so novel, after all.

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Researchers find that stem cells in the developing brain of modern humans take longer to divide and make fewer errors when distributing their chromosomes to their daughter cells, compared to those of Neanderthals.

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A newly identified 16th century horse specimen is among the oldest domestic horses from the Americas known to date, and its DNA helps clarify the history of horses in the Western Hemisphere, according to a new study.

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Whether by the spear or the plow, humans have been homogenizing the mammal communities of North America for 10,000-plus years, says a new analysis of 8,831 fossils representing 365 species.

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Which group of mammals has the more 'primitive' reproductive strategy -- marsupials, with their short gestation periods, or humans and other placental mammals, which have long gestation periods? For decades, biologists viewed marsupial reproduction as 'more primitive.' But scientists have discovered that a third group of mammals, the long-extinct multituberculates, had a long gestation period like placental mammals. Since multituberculates split off from the rest of the mammalian lineage before placentals and marsupials had even evolved, these findings question the view that marsupials were 'less advanced' than their placental cousins.

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Warm-bloodedness is a key mammal trait, but it's been a mystery when our ancestors evolved it. A new study points to an unlikely source for telling a fossil animal's body temperature: the size of tiny structures in their inner ears. The fluid in our ears becomes runnier at higher temperatures, so animals with warm bodies don't need as big of canals for it to flow through. Turns out, mammal ancestors became warm-blooded nearly 20 million years later than previously thought.

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The study of the genomes of our closest relatives, the Neanderthals and Denisovans, has opened up new research paths that can broaden our understanding of the evolutionary history of Homo sapiens. A new study has made an estimation of the time when some of the genetic variants that characterize our species emerged. It does so by analyzing mutations that are very frequent in modern human populations, but not in these other species of archaic humans.

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Australia's first fossil vulture has been confirmed more than 100 years after it was first described as an eagle. The discovery highlights the diversity of Australian megafauna and other animals many thousands of years ago in the Pleistocene period.

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For the first time, researchers successfully sequenced the genome of ancient human fossils from the Late Pleistocene in southern China. The data suggests that the mysterious hominin belonged to an extinct maternal branch of modern humans that might have contributed to the origin of Native Americans.

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In a new paper, researchers challenge the longstanding view that the force of natural selection in humans must decline to zero once reproduction is complete. They assert that a long post-reproductive lifespan is not just due to recent advancements in health and medicine. The secret to our success? Our grandparents.

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According to a new study, the first louse to take up residence on a mammalian host likely started out as a parasite of birds. That host-jumping event tens of millions of years ago began the long association between mammals and lice, setting the stage for their coevolution and offering more opportunities for the lice to spread to other mammals.