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Categories: Ecology: Extinction, Paleontology: Early Mammals and Birds

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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.

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Starting in the 1990s, Island Fox populations began to dwindle due to an outbreak of canine distemper and an increase in attacks by golden eagles. Some islands saw their population drop to as low as 15 individuals, but conservation efforts by the Federal government restored numbers by 2017. A new study reveals a worrying decrease in genetic diversity within the species, signaling a new threat to the Channel Islands foxes' survival. The decrease in genetic diversity reduces the foxes' ability to adapt to future challenges, such as climate change and introduced pathogens, putting their survival at risk once again. Although the foxes have low genetic diversity, they possess diverse gut microbiomes that could help them cope with environmental changes.

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A new study examined how bivalves -- the group that includes clams, mussels, scallops, and oysters -- evolved among many others in the period of rapid evolution known as the Cambrian Explosion. The team found that though many other lineages burst into action and quickly evolved a wide variety of forms and functions, the bivalves lagged behind. The study has implications for how we understand evolution and the impact of extinctions.

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Genetic analysis shows dingo populations have significantly less dog ancestry than previously thought.

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Scientists have developed and validated an assay that could be used to diagnose Indian strains of the amphibian chytrid fungus that were not detected by previous tests. The novel assay also works for other better-known strains from other parts of the world, such as the one present in Panama.

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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.

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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.

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Biologists reveals how coral cells tag friendly algae before ingesting them, initiating a mutually beneficial relationship. This information could guide next-level coral conservation efforts.

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Conservationists have argued that the presence of wolves and other apex predators, so named because they have no known predators aside from people, can help keep smaller predator species in check. New research shows that in Washington state, the presence of two apex predators -- wolves and cougars -- does indeed help keep populations of two smaller predators in check. But by and large the apex predators were not killing and eating the smaller predators, known as mesopredators. Instead, they drove the two mesopredator species -- bobcats and coyotes -- into areas with higher levels of human activity. And people were finishing the job.

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Scientists have discovered a new species of mosasaur, a sea-dwelling lizard from the age of the dinosaurs, with strange, ridged teeth unlike those of any known reptile. Along with other recent finds from Africa, it suggests that mosasaurs and other marine reptiles were evolving rapidly up until 66 million years ago, when they were wiped out by an asteroid along with the dinosaurs and around 90% of all species on Earth.

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A new study examines indicators of mental wellbeing in wild animals to improve conservation efforts.

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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.

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Which energy type promotes the biodiversity of beetles living in dead wood in the forest? That depends entirely on where the beetles are in the food chain.

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Small-scale wildlife surveys can reveal the health of entire ecosystems, new research shows.

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Birds across the Americas are getting smaller and longer-winged as the world warms, and the smallest-bodied species are changing the fastest.

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For decades, scientists have used the amount of seaweed at the ocean's surface as a proxy for the health of coral reefs below. However, a new global study of more than 1,200 marine locations over a 16-year period reveals that this approach has been misleading -- and may even have hidden signs of reef stress.

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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.

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In the face of global warming and other environmental changes, corals in the Atlantic Ocean have declined precipitously in recent years, while corals in the Pacific and Indian Oceans are faring better. By describing several species of symbiotic algae that these corals need to grow, an international team has found that these mutualistic relationships from the Indo-Pacific may be more flexible and ultimately resilient to higher ocean temperatures than those in the Atlantic.

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Like animals, many plant species are struggling to adapt to a human-dominated planet. However, plants are often overlooked in conservation efforts, even though they are cheaper and easier to protect than animals and play a pivotal role in bolstering our food, fuel, and medical systems. A plant ecologist suggests an approach for preventing all future land plant extinctions across the globe which includes training more plant experts, building an online 'metaherbarium,' and creating 'microreserves.'

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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.