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Category: Biology


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.

Scientists have been studying how visual space is mapped in the cerebral cortex for many decades under the assumption that the map is equal for lights and darks. Surprisingly, recent work demonstrates that visual brain maps are dark-centric and that, just as stars rotate around black holes in the Universe, lights rotate around darks in the brain representation of visual space. The work was done by Jens Kremkow and collaborators in the laboratories of Jose Manuel Alonso at the State University of New York College of Optometry and will be published in the May 5, 2016 issue of Nature (advance online publication and press embargo lifted on April 27, 2016 at 1800 London time / 1300 US Eastern Time). A similar result will be reported in the same issue of Nature by Kuo-Sheng Lee et al. in the laboratories of David Fitzpatrick at the Max Planck Florida Institute for Neuroscience.

The work of University of Adelaide researchers is shedding new light on the evolution of what are believed to be the largest bears that ever walked the Earth.

Using cutting-edge imaging technology, University of California, Irvine biologists have determined that uncontrolled fluctuations (known at "noise) in the concentration of the vitamin A derivative Retinoic acid (RA) can lead to disruptions in brain organization during development.

Studies in a group of tropical birds have revealed one of the fastest limb muscles on record for any animal with a backbone. The muscle, which can move the wing at more than twice the speeds required for flying, has evolved in association with extravagant courtship displays that involve rapid limb movements, according to a paper to be published in the journal eLife.

EPFL scientists propose a new way of understanding of how the brain processes unconscious information into our consciousness. According to the model, consciousness arises only in time intervals of up to 400 milliseconds, with gaps of unconsciousness in between.


Found throughout the Caribbean, the bananaquit has smaller flight muscles and longer legs on islands with fewer predators.
In groundbreaking new work, Natalie Wright, a postdoctoral fellow at the University of Montana, has discovered a predictable trend in the evolution of bird shape.


This image shows ants tending to some leave hoppers.
University of Melbourne scientists have shone a new light into the complexities of ant communication, with the discovery that ants not only pick up information through their antennae, but also use them to convey social signals.

An international team of scientists, from three Brazilian universities and one UK university, have discovered a new fossil reptile that lived 250 million years ago in the state of Rio Grande do Sul, southernmost Brazil. The species has been identified from a mostly complete and well preserved fossil skull that the team has named Teyujagua paradoxa.

In the first study to use new methods to track antibiotic resistance through the process of intensively farming and slaughtering cattle, scientists have discovered a "startling" lack of resistance genes in meat.

People are intuitive physicists, knowing from birth how objects under the influence of gravity are likely to fall, topple or roll. In a new study, scientists have found the brain cells apparently responsible for this innate wisdom.


Here is an artist's drawing of the abelisaur.
An unidentified fossilised bone in a museum has revealed the size of a fearsome abelisaur and may have solved a hundred-year old puzzle.

Sometimes evolution proceeds much more rapidly than we might think. Genetic analysis makes it possible to detect the earliest stages of species formation and to gain a better understanding of speciation processes. For example, a study just published in PLOS Genetics by researchers from Eawag and the University of Bern - investigating rapid speciation in threespine stickleback in and around Lake Constance - shows that a species can begin to diverge very rapidly, even when the two daughter species breed alongside one another simultaneously.

In a surprise result, James Cook University scientists have found female blacktip reef sharks and their young stay close to shore over long time periods, with adult males only appearing during the breeding season.


Black-headed flying fox amongst a grey-headed colony.
For the first time researchers have uncovered a unique ability in bats which allows them to carry but remain unaffected by lethal diseases.

The mechanism used by the National Institutes of Health (NIH) to allocate government research funds to scientists whose grants receive its top scores works essentially no better than distributing those dollars at random, new research suggests.


Recurrent DSB clusters in neural stem/progenitor cells are shown.
The genome of developing brain cells harbors 27 clusters or hotspots where its DNA is much more likely to break in some places than others, researchers from the Program in Cellular and Molecular Medicine (PCMM) at Boston Children's Hospital, Harvard Medical School, and the Howard Hughes Medical Institute report in the journal Cell. Those hotspots appear in genes associated with brain tumors and a number of neurodevelopmental and neuropsychiatric conditions, raising new questions about these conditions' origins, as well as how the brain generates a diversity of circuitry during development.


Biologists have found genetic mechanisms that let the Atlantic molly live in toxic, acidic water.
A Washington State University biologist has found the genetic mechanisms that lets a fish live in toxic, acidic water. The discovery opens the door to new insights into the functioning of other "extremophiles" and how they adapt to their challenging environments.

In the brain, the visual cortex processes visual information and passes it from lower to higher areas of the brain. However, information also flows in the opposite direction, e.g. to direct attention to particular stimuli. But how does the brain know which path the information should take? Researchers at the Ernst Strüngmann Institute (ESI) for Neuroscience in Frankfurt in Cooperation with Max Planck Society have now demonstrated that the visual cortex of human subjects uses different frequency channels depending on the direction in which information is being transported. Their findings were only possible thanks to previous research with macaque monkeys. They might help to understand the cause of psychiatric illnesses in which the two channels appear to be mixed up.

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