Chronic stress could be one reason why some animal orphans have shorter lives and less offspring. Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig and the Institute of Cognitive Sciences, CNRS in Lyon assessed if, as orphan humans, orphan chimpanzees are exposed to chronic stress. They found that maternal loss is stressful but orphans experience little chronic stress since stress hormones return to normal after two years, possibly thanks to care provided by other chimpanzees.
Outside the breeding season many parrots live in dynamic social systems in which individuals travel and forage. These flocks are characterised by frequent changes in composition and their dynamic nature entails a unique set of challenges, such as potential increased aggression and competition for resources. Therefore, the ability to selectively choose the right flock members may be essential to maximise individual fitness. In a new study, researchers from the University of Copenhagen and Aarhus University is shedding light over social interactions in parrots.
A new species of nematode (roundworm), named Cryptaphelenchus abietis, was isolated from bark beetles from a dead log collected in Nagano, Japan. The females of this newly described species can be identified based on the size of the post-uterine sac and the conical tail with an elongate posterior part. The males have seven genital papillae and a narrow bursal flap-like extension. The culturability of this species means it may be useful in further nematode research.
Professor DENG Tao from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences and his collaborators from China and the U.S.A. recently reported a new species Paraceratherium linxiaense sp. nov., which offers important clues to the dispersal of giant rhinos across Asia.
A new study in the Canadian Journal of Earth Sciences shows that medium-sized predators all but disappeared late in dinosaur history wherever Tyrannosaurus rex and its close relatives rose to dominance. In those areas -- lands that eventually became central Asia and Western North America -- juvenile tyrannosaurs stepped in to fill the missing ecological niche previously held by other carnivores.
Once thought to be extinct, lobe-finned coelacanths are enormous fish that live deep in the ocean. Now, researchers reporting in the journal Current Biology on June 17 have evidence that, in addition to their impressive size, coelacanths also can live for an impressively long time--perhaps nearly a century.
Pheromones mediate asymmetric mating behavior in isogamous yeast
A new paper in the journal Cognition examines the visual complexity of written language and how that complexity has evolved.
In the majority of insects, metamorphosis fosters completely different looking larval and adult stages. This "decoupling" of life stages is thought to allow for adaptation to different environments. Researchers of the University of Bonn now falsified this text book knowledge of evolutionary theory for stoneflies. They found that the ecology of the larvae largely determines the morphology of the adults by investigating 219 earwig and stonefly species at high-resolution particle accelerators.
Getting energy and nutrients from the environment -- that is, eating -- is such an important function that it has been regulated through sophisticated mechanisms over hundreds of millions of years. Some of these mechanisms are only now beginning to be unraveled. A group at the Spanish National Cancer Research Centre (CNIO) has found one of their key components -- a switch that controls the ability of organisms to adapt to low cellular nutrient levels.