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Categories: Anthropology: Early Humans, Paleontology: Early Mammals and Birds
Published Lost giants: New study reveals the abundance decline of African megafauna
(via sciencedaily.com) Original source A groundbreaking new paper focuses on the size and abundance of living and fossil African large mammals, shedding light on the ecological dynamics behind the decline of these iconic creatures. The findings challenge previous assumptions about the causes of megafaunal extinctions in Africa and provide new insights into the restructuring of ecosystems over millions of years.
Published Life before air conditioning: Curly hair kept early humans cool
(via sciencedaily.com) Original source Curly hair does more than simply look good -- it may explain how early humans stayed cool while conserving water, according to researchers who studied the role human hair textures play in regulating body temperature. The findings can shed light on an evolutionary adaptation that enabled the human brain to grow to modern-day sizes.
Published Remains of an extinct world of organisms discovered
(via sciencedaily.com) Original source Newly discovered biomarker signatures point to a whole range of previously unknown organisms that dominated complex life on Earth about a billion years ago. They differed from complex eukaryotic life as we know it, such as animals, plants and algae in their cell structure and likely metabolism, which was adapted to a world that had far less oxygen in the atmosphere than today.
Published Geneticists discover hidden 'whole genome duplication' that may explain why some species survived mass extinctions
(via sciencedaily.com) Original source Geneticists have unearthed a major event in the ancient history of sturgeons and paddlefish that has significant implications for the way we understand evolution. They have pinpointed a previously hidden 'whole genome duplication' (WGD) in the common ancestor of these species, which seemingly opened the door to genetic variations that may have conferred an advantage around the time of a major mass extinction some 200 million years ago.
Published Dinosaurs were the first to take the perspectives of others
(via sciencedaily.com) Original source Understanding that others hold different viewpoints from your own is essential for human sociality. Adopting another person's visual perspective is a complex skill that emerges around the age of two. A new study suggests that this ability first arose in dinosaurs, at least 60 million years before it appeared in mammals. These findings challenge the idea that mammals were the originators of novel and superior forms of intelligence in the wake of the dinosaur extinction.
Published Fossils of a saber-toothed top predator reveal a scramble for dominance leading up to 'the Great Dying'
(via sciencedaily.com) Original source A tiger-sized saber-toothed creature called Inostrancevia has previously only been found in Russia. But scientists have discovered its fossils in South Africa, suggesting that it migrated 7,000 miles across the supercontinent Pangaea during the world's worst mass extinction 252 million years ago. Heading to South Africa allowed it to fill a gap in a faraway ecosystem that had lost its top predators.
Published Humanity's earliest recorded kiss occurred in Mesopotamia 4,500 years ago
(via sciencedaily.com) Original source Written sources from Mesopotamia suggest that kissing in relation to sex was practiced by the peoples of the ancient Middle East 4,500 years ago.
Published Homo sapiens likely arose from multiple closely related populations
(via sciencedaily.com) Original source In testing the genetic material of current populations in Africa and comparing against existing fossil evidence of early Homo sapiens populations there, researchers have uncovered a new model of human evolution -- overturning previous beliefs that a single African population gave rise to all humans.
Published Researcher uses mammal DNA to zoom into the human genome with unprecedented resolution
(via sciencedaily.com) Original source Scientists have precisely identified base pairs of the human genome that remained consistent over millions of years of mammalian evolution, and which play a crucial role in human disease. The team analyzed the genomes of 240 mammals, including humans and identified base pairs that were 'constrained' -- meaning they remained generally consistent -- across mammal species over the course of evolution. The most constrained base pairs in mammals were over seven times more likely to be causal for human disease and complex trait, and over 11 times more likely when researchers looked at the most constrained base pairs in primates alone.
Published Human ancestors preferred mosaic landscapes and high ecosystem diversity
(via sciencedaily.com) Original source A new study finds that early human species adapted to mosaic landscapes and diverse food resources, which would have increased our ancestor's resilience to past shifts in climate.
Published Evidence of Ice Age human migrations from China to the Americas and Japan
(via sciencedaily.com) Original source Scientists have used mitochondrial DNA to trace a female lineage from northern coastal China to the Americas. By integrating contemporary and ancient mitochondrial DNA, the team found evidence of at least two migrations: one during the last ice age, and one during the subsequent melting period. Around the same time as the second migration, another branch of the same lineage migrated to Japan, which could explain Paleolithic archeological similarities between the Americas, China, and Japan.
Published Nose shape gene inherited from Neanderthals
(via sciencedaily.com) Original source Humans inherited genetic material from Neanderthals that affects the shape of our noses, finds a new study.
Published Scientists recover an ancient woman's DNA from a 20,000-year-old pendant
(via sciencedaily.com) Original source An international research team has for the first time successfully isolated ancient human DNA from a Paleolithic artefact: a pierced deer tooth discovered in Denisova Cave in southern Siberia. To preserve the integrity of the artefact, they developed a new, nondestructive method for isolating DNA from ancient bones and teeth. From the DNA retrieved they were able to reconstruct a precise genetic profile of the woman who used or wore the pendant, as well as of the deer from which the tooth was taken. Genetic dates obtained for the DNA from both the woman and the deer show that the pendant was made between 19,000 and 25,000 years ago. The tooth remains fully intact after analysis, providing testimony to a new era in ancient DNA research, in which it may become possible to directly identify the users of ornaments and tools produced in the deep past.
Published New tusk-analysis techniques reveal surging testosterone in male woolly mammoths
(via sciencedaily.com) Original source Traces of sex hormones extracted from a woolly mammoth's tusk provide the first direct evidence that adult males experienced musth, a testosterone-driven episode of heightened aggression against rival males, according to a new study.
Published Scientists present evidence for a billion-years arms race between viruses and their hosts
(via sciencedaily.com) Original source Researchers have proposed a new evolutionary model for the origin of a kingdom of viruses called Bamfordvirae, suggesting a billion-years evolutionary arms race between two groups within this kingdom and their hosts.
Published New research redefines mammalian tree of life
(via sciencedaily.com) Original source Scientists from around the globe are using the largest mammalian genomic dataset in history to determine the evolutionary history of the human genome in the context of mammalian evolutionary history. Their ultimate goal is to better identify the genetic basis for traits and diseases in people and other species.
Published Information 'deleted' from the human genome may be what made us human
(via sciencedaily.com) Original source What the human genome is lacking compared with the genomes of other primates might have been as crucial to the development of humankind as what has been added during our evolutionary history, according to a new study led by researchers at Yale and the Broad Institute of MIT and Harvard. The new findings, published April 28 in the journal Science, fill an important gap in what is known about historical changes to the human genome.
Published Mammalian evolution provides hints for understanding the origins of human disease
(via sciencedaily.com) Original source Even though it is important to know where these variations are located in the genome, it's also useful to know how or why these genetic variations happened in the first place.
Published Searching for ancient bears in an Alaskan cave led to an important human discovery
(via sciencedaily.com) Original source Genetic analysis links 3,000-year-old bone found in cave to modern Alaska Natives.
Published X-ray analysis sheds new light on prehistoric predator's last meal
(via sciencedaily.com) Original source We now know more about the diet of a prehistoric creature that grew up to two and a half meters long and lived in Australian waters during the time of the dinosaurs, thanks to the power of x-rays. Researchers used micro-CT scans to peer inside the fossilized stomach remains of a small marine reptile -- a plesiosaur nicknamed 'Eric' after a song from the comedy group Monty Python -- to determine what the creature ate in the lead up to its death.