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Category: Biology

Stanford University School of Medicine scientists have identified a brain circuit that's indispensable to the sleep-wake cycle. This same circuit is also a key component of the reward system, an archipelago of interconnected brain clusters crucial to promoting behavior necessary for animals, including humans, to survive and reproduce.


This is a paleoartist's reconstruction of a ptesosaur.
Scientists today announced the discovery of a new species of pterosaur from the Patagonia region of South America. The cranial remains were in an excellent state of preservation and belonged to a new species of pterosaur from the Early Jurassic. The researchers have named this new species 'Allkauren koi' from the native Tehuelche word 'all' for 'brain', and 'karuen' for 'ancient'.


Cyanobacterial neurotoxin β-N-methylamino-L-alanine (BMAA) and Mercury are detected in sharks from the Atlantic and Pacific Oceans.
In a new study, University of Miami (UM) scientists found high concentrations of toxins linked to neurodegenerative diseases in the fins and muscles of 10 species of sharks. The research team suggests that restricting consumption of sharks can have positive health benefits for consumers and for shark conservation, since several of the sharks analyzed in the study are threatened with extinction due to overfishing.


This is a fossil ptilodactyline beetle found in amber from Mexico. The black arrow points to pollinia attached to the beetle's mouthparts.
When most people hear the word "pollinator," they think of bees and butterflies. However, certain beetles are known to pollinate plants as well, and new fossil evidence indicates that they were doing so 20 million years ago.


Squinting won't help you spot the fish in this photo. These snub-nosed darts blend seamlessly into their watery surroundings with help from their silvery reflective skin.
In a matchup of animal superpowers, a clever form of camouflage might beat super sight -- at least in the ocean.


Image of a thin-section through an Orthacanthus coprolite with a black box indicating the tooth of an Orthacanthus.
Scientists have discovered macabre fossil evidence suggesting that 300 million-year-old sharks ate their own young, as fossil poop of adult Orthacanthus sharks contained the tiny teeth of juveniles. These fearsome marine predators used protected coastal lagoons to rear their babies, but it seems they also resorted to cannibalising them when other food sources became scarce.


Birds' reproductive strategies have gone through a series of stages, from dinosaurs to today.
What really did come first--the chicken or the egg? Birds' reproductive biology is dramatically different from that of any other living vertebrates, and ornithologists and paleontologists have long wondered how and when the unique features of bird reproduction originated. A new Review in The Auk: Ornithological Advances examines answers from three sources--modern birds, fossils of primitive birds, and fossils of the dinosaurs from which birds are descended--to shed new light on the subject.


Tiger shark eating a turtle,
Tiger sharks are known as impressive predators that hunt and consume almost anything from birds to sea turtles. But when the opportunity presents itself, these sharks easily convert into the role of marine scavengers. This behavior was reported¹ in Springer's journal Behavioral Ecology and Sociobiology by a team of American, Australian and British researchers led by Neil Hammerschlag of the University of Miami Rosenstiel School of Marine and Atmospheric Science in the US. They re-evaluated satellite tracking data collected from tiger sharks and green turtles off the Great Barrier Reef's Raine Island, which is home to the world's largest concentration of nesting green turtles.


A mantis shrimp displaying its meral spots, visible as two purple dots.
Mantis shrimp, often brightly colored and fiercely aggressive sea creatures with outsized strength, use the ultraviolet reflectance of their color spots as well as chemical signals to assess the likelihood of victory in combat, according to research led by a Tufts University doctoral candidate. The findings, published today in Royal Society Open Science, mark the first time that researchers have demonstrated that mantis shrimp (Neogonodactylus oerstedii) use both color and chemical cues when fighting over resources.


Frigatebirds reaches a wingspan of over two metres. They are excellent gliders and can cover several hundred kilometers a day.
For the first time, researchers have discovered that birds can sleep in flight. Together with an international team of colleagues, Niels Rattenborg from the Max Planck Institute for Ornithology in Seewiesen measured the brain activity of frigatebirds and found that they sleep in flight with either one cerebral hemisphere at a time or both hemispheres simultaneously. Despite being able to engage in all types of sleep in flight, the birds slept less than an hour a day, a mere fraction of the time spent sleeping on land. How frigatebirds are able to perform adaptively on such little sleep remains a mystery.

When reaching into a pocket or purse, it is easy to use the sense of touch to distinguish keys from loose change. Our brains seamlessly integrate the tactile, sensory cues from our fingers with hand movements to perceive the different objects.

The discovery of a theropod dinosaur with Tyrannosaurus rex-like arms suggests that these unusual forelimbs may have evolved multiple times, according to a study published July 13, 2016 in the open-access journal PLOS ONE by Sebastián Apesteguía from the Universidad Maimónides, Argentina, and colleagues.

Ants, it turns out, are extremely good at estimating the concentration of other ants in their vicinity. This ability appears to play a role in several communal activities, particularly in the voting procedure whereby an ant colony selects a new nest.


Flow map in the third ventricle of the mouse brain.
We have all bumped our heads at some point, and such incidents are usually harmless. This is thanks to fluid-filled chambers in our brain that offset minor knocks and jolts and provide padding for sensitive components of our nervous system. Cerebral fluid, however, has more than just a protective function: It removes cellular waste, supplies our nervous tissue with nutrients, and transports important messenger substances. How these messenger substances are actually being delivered to their destination in the brain, however, was unclear until now. Göttingen-based Max Planck researchers have now discovered that tiny cilia on the surface of specialized cells could lead the way. Through synchronized beating movements, they create a complex network of dynamic flows that act like conveyor belts transporting molecular "freight". The results obtained by the scientists suggest that these flows send messenger substances directly to where they are needed.


Beer bottles are pictured.
By activating particular neurons, we may be able to influence alcohol drinking behavior, according to new findings published by researchers at the Texas A&M Health Science Center College of Medicine in the journal Biological Psychiatry.


This is a reconstruction of the young, deformed Telmatosaurus individual, with the ameloblastoma just becoming visible on its lower left jaw.
The first-ever record of a tumourous facial swelling found in a fossil has been discovered in the jaw of the dwarf dinosaur Telmatosaurus transsylvanicus, a type of primitive duck-billed dinosaur known as a hadrosaur.


Hedgehogs cope more easily with city living than you might think.
A species that is 15 million years old, hedgehogs have survived all kinds of environmental changes over the years, including urbanisation. Surprisingly, cities have often been found to have higher hedgehog populations than rural areas. Understanding why this is could help us to protect them in the future.

An international team of scientists from Oxford University, UK, and Tel-Hai College, Israel, has shown that pea plants can demonstrate sensitivity to risk - namely, that they can make adaptive choices that take into account environmental variance, an ability previously unknown outside the animal kingdom.


Male and female of the beautiful demoiselle (Calopteryx virgo) in the so-called "mating wheel".
Traditionally, the evolutionary development of an insect species has been explained by the notion that the female insect chooses her male partner based on size and other factors, so-called assortative mating. These mating patterns have also been believed to partially explain how the isolation between different species is maintained.


Damien Esquerre with a python.
A new study into pythons and boas has for the first time found the two groups of snakes evolved independently to share similar traits, shedding new light on how the reptiles evolved.


A mating pair of melanic peppered moths
Researchers from the University of Liverpool have identified and dated the genetic mutation that gave rise to the black form of the peppered moth, which spread rapidly during Britain's industrial revolution.


Hemiphlebia mirabilis is a rare species in every sense: it is the most primitive dragonfly known to man, it has unique reproductive behaviors and was believed to be extinct.
The dragonfly considered the most primitive in the world lives in Australia and Tasmania, and was believed to be extinct four decades ago. But it is far from being so. A Spanish researcher has observed thousands of these insects in one of the few habitats in which it has been detected and it displays sexual behaviour that is unique, not only directed towards reproduction.


This is the male fiddler crab Uca lactea.
The vibrations and pulses that male fiddler crabs produce when they are trying to lure females into their burrows to mate are surprisingly informative. These signals serve as a type of "Morse code" that the females decipher to learn more about the size and stamina of their suitors. This is according to a study by Japanese researchers Fumio Takeshita of Nagasaki University and Minoru Murai of the University of the Ryukyu, published in Springer's journal The Science of Nature.


Male and female worms engage in different behaviors, which may result from sex-specific wiring patterns in the brain.
Nematode worms may not be from Mars or Venus, but they do have sex-specific circuits in their brains that cause the males and females to act differently. According to new research published in Nature, scientists have determined how these sexually dimorphic (occurring in either males or females) connections arise in the worm nervous system. The research was funded by the NIH's National Institute of Neurological Disorders and Stroke (NINDS).


This is a male specimen of the new long-horned beetle species Borneostyrax cristatus gen. et sp. nov.
A remarkably high diversity of the wingless long-horned beetles in the mountains of northern Borneo is reported by three Czech researchers from the Palacký University, Olomouc, Czech Republic. Apart from the genera and species new to science, the entomologists report the first case of reproduction by live birth in this rarely collected group of beetles.


Fossil and reconstruction of Atopodentatus unicus.
Some strange creatures cropped up in the wake of one of Earth's biggest mass extinctions 252 million years ago. In 2014, scientists discovered a bizarre fossil--a crocodile-sized sea-dwelling reptile, Atopodentatus unicus, that lived 242 million years ago in what today is southwestern China. Its head was poorly preserved, but it seemed to have a flamingo-like beak. However, in a paper published May 6 in Science Advances, Dr. LI Chun, Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences, and his international team described two new specimens and revealed what was really going on--that "beak" is actually part of a hammerhead-shaped jaw apparatus, which it used to feed on plants on the ocean floor. It's the earliest known example of an herbivorous marine reptile.


Evan R. Buechley releases an adult Egyptian Vulture in Armenia after tagging it with a satellite tracking device (visible on the back of the bird).
Vultures. Cartoon characters in parched deserts often wish them to disappear, since circling vultures are a stereotypical harbinger of death. But, joking aside, vultures in some parts of the world are in danger of disappearing. And according to a new report from University of Utah biologists, such a loss would have serious consequences for ecosystems and human populations alike.

In December 2015 an international group of scientists convened in Austria to discuss the imminent extinction of the northern white rhinoceros and the possibility of bringing the species back from brink of extinction. The discussions of this historic meeting appear in the international Journal Zoo Biology. The publication of this work is designed as part of the ongoing effort to raise awareness for the extinction crisis facing rhinos and many other species while also reaching out to the scientific community to share and gather information.


Sleeping bearded dragon (Pogona vitticeps).
Behavioural sleep is ubiquitous among animals, from insects to man. In humans, sleep is also characterized by brain activity: periods of slow-wave activity are each followed by short phases of Rapid-Eye-Movement sleep (REM sleep). These electrical features of brain sleep, whose functions are not well understood, have so far been described only in mammals and birds, but not in reptiles, amphibians or fish. Yet, birds are reptiles--they are the feathered descendants of the now extinct dinosaurs. How then did brain sleep evolve? Gilles Laurent and members of his laboratory at the Max Planck Institute for Brain Research in Frankfurt, Germany, describe for the first time REM and slow-wave sleep in a reptile, the Australian dragon Pogona vitticeps. This suggests that brain sleep dates back at least to the evolution of the amniotes, that is, to the beginning of the colonization of terrestrial landmass by vertebrate animals.


A juvenile lace coral (Pocillopora damicornis), with coral tissue and algal symbionts (brown dots within the tissue) covering the newly grown skeleton.
In a study published today, researchers from the University of Hawai'i at Mānoa (UHM), Rutgers University, and the University of Haifa identified key and novel components of the molecular "toolkit" that allow corals to build their skeletons (called biomineralization) and described when -- in the transformation from floating larvae to coral skeleton -- these components are used.

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