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Categories: Biology: Evolutionary, Ecology: Endangered Species
Published How plants use sugar to produce roots



Along with sugar reallocation, a basic molecular mechanism within plants controls the formation of new lateral roots. Botanists have demonstrated that it is based on the activity of a certain factor, the target of rapamycin (TOR) protein. A better understanding of the processes that regulate root branching at the molecular level could contribute to improving plant growth and therefore crop yields, according to the research team leader.
Published Fossils of a saber-toothed top predator reveal a scramble for dominance leading up to 'the Great Dying'



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 Out of the frying pan: Coyotes, bobcats move into human-inhabited areas to avoid apex predators -- only to be killed by people



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.
Published Fossil of mosasaur with bizarre 'screwdriver teeth' found in Morocco



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.
Published Scales or feathers? It all comes down to a few genes



Scales, spines, feathers and hair are examples of vertebrate skin appendages, which constitute a remarkably diverse group of micro-organs. Despite their natural multitude of forms, these appendages share early developmental processes at the embryonic stage. Researchers have discovered how to permanently transform the scales that normally cover the feet of chickens into feathers, by specifically modifying the expression of certain genes.
Published Assessing emotions in wild animals



A new study examines indicators of mental wellbeing in wild animals to improve conservation efforts.
Published What did the earliest animals look like?



Surprisingly, genome comparisons have failed to resolve a major question in animal evolution: Which living animals are the descendants of the earliest animals to evolve in the world's oceans? Scientists performed a detailed chromosomal analysis that comes down definitively in favor of comb jellies, or ctenophores, as the most recent common ancestor of all animals, or the sister taxa to all animals. Sponges evolved later.
Published Jaw shapes of 90 shark species show: Evolution driven by habitat



Researchers investigated how the jaw shape of sharks has changed over the course of evolution. Their conclusion: in the most widespread shark species, the jaws show relatively little variation in shape over millions of years; most variable jaws were found for deep-sea sharks.
Published Rare tropical plant gains appetite for meat



Under certain circumstances, a rare tropical plant develops into a carnivore. A research team has now deciphered the mechanism responsible for this.
Published Butterfly tree of life reveals an origin in North America



Scientists have discovered where butterflies originated and which plants the first butterflies relied on for food. To reach these conclusions, researchers created the world's largest butterfly tree of life, which they used as a guide to trace trace the evolution of butterflies through time in a four-dimensional puzzle that led back to North and Central America.
Published Researcher uses mammal DNA to zoom into the human genome with unprecedented resolution



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 Global warming puts whales in the Southern Ocean on a diet



In the autumn, when right whales swim towards the coasts of South Africa, they ought to be fat and stuffed full. But in recent years, they have become thinner because their food is disappearing with the melting sea ice.
Published How bacteria evolve resistance to antibiotics



Bacteria can rapidly evolve resistance to antibiotics by adapting special pumps to flush them out of their cells, according to new research. Antimicrobial resistance is a growing problem of global significance. The rise of resistant 'superbugs' threatens our ability to use antimicrobials like antibiotics to treat and prevent the spread of infections caused by microorganisms. It is hoped that the findings will improve how antibiotics are used to help prevent further spread of antimicrobial resistance.
Published Like ancient mariners, ancestors of Prochlorococcus microbes rode out to sea on exoskeleton particles



Throughout the ocean, billions upon billions of plant-like microbes make up an invisible floating forest. As they drift, the tiny organisms use sunlight to suck up carbon dioxide from the atmosphere. Collectively, these photosynthesizing plankton, or phytoplankton, absorb almost as much CO2 as the world’s terrestrial forests. A measurable fraction of their carbon-capturing muscle comes from Prochlorococcus — an emerald-tinged free-floater that is the most abundant phytoplankton in the oceans today. New research suggests the microbe's ancient coastal ancestors colonized the ocean by rafting out on chitin particles.
Published Human ancestors preferred mosaic landscapes and high ecosystem diversity



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 Hammerhead sharks hold their breath on deep water hunts to stay warm



Scalloped hammerhead sharks hold their breath to keep their bodies warm during deep dives into cold water where they hunt prey such as deep sea squids. This discovery provides important new insights into the physiology and ecology of a species that serves as an important link between the deep and shallow water habitats.
Published Invading insect could transform Antarctic soils



A tiny flightless midge which has colonized Antarctica's Signy Island is driving fundamental changes to the island's soil ecosystem, a study shows.
Published A journey to the origins of multicellular life: Long-term experimental evolution in the lab



Over 3,000 generations of laboratory evolution, researchers watched as their model organism, 'snowflake yeast,' began to adapt as multicellular individuals. In new research, the team shows how snowflake yeast evolved to be physically stronger and more than 20,000 times larger than their ancestor. Their study is the first major report on the ongoing Multicellularity Long-Term Evolution Experiment (MuLTEE), which the team hopes to run for decades.
Published Crops evolved by swapping genetic modules between cells



Comparing individual cells across corn, sorghum, and millet reveals evolutionary differences among these important cereal crops, according to a new study. The findings bring researchers closer to pinpointing which genes control important agricultural traits such as drought tolerance, which will help scientists faced with a changing climate adapt crops to drier environments.
Published African rhinos share retroviruses not found in Asian rhinos or other related species



Rhinoceros belong to a mammalian order called odd-toed ungulates that also include horses and tapirs. They are found in Africa and Asia. Until recently, evidence suggested that throughout their evolutionary history, gamma-retroviruses such as Murine leukemia virus had not colonized their genomes, unlike most other mammalian orders. The colonization process is called retroviral endogenization and has resulted in most mammalian genomes being comprised of up to ten percent retroviral like sequences.