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rasha kamel
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"Each spring, millions of nocturnal Bogong moths hatch across breeding grounds throughout southeastern Australia before flying over 1,000 kilometers through the dark night to reach a limited number of high alpine caves in the Australian Alps. After a few months of summer dormancy in those cool mountain caves, the moths fly right back to the breeding grounds where they were born. Now, researchers reporting in Current Biology on June 21 have found that the moths, like migratory birds, depend on the Earth's magnetic field to guide them on their way.

The discovery offers the first reliable evidence that nocturnal insects can use the Earth's magnetic field to steer flight during migration, the researchers say.

"When we began this study, we were convinced that the Bogong moth would exclusively use celestial cues in the sky, such as the stars and the moon, for navigation during migration," says Eric Warrant of the University of Lund, Sweden. "This, it turned out, was not the case. We were very surprised when we discovered that these moths could sense the earth's magnetic field just like night-migratory birds—and probably for the same reason."

Bogong moths and monarch butterflies are the only known insects to migrate over such long distances, and along such a specific route, to a distinct and geographically restricted destination visited by thousands of previous generations. In the new study, Warrant, David Dreyer, and colleagues set out to explore how such a small animal, with its tiny brain and nervous system, could travel so precisely and so far, having never been to their destination before. How could the same individuals then find their way back again after months in the mountains?".

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"Scientists have demonstrated for the first time that horses integrate human facial expressions and voice tones to perceive human emotion, regardless of whether the person is familiar or not.

Recent studies showed horses possesses high communication capabilities, and can read the emotions of their peers through facial expressions and contact calls, or whinnies. Horses have long been used as a working animal and also as a companion animal in sports and leisure, establishing close relationships with humans, just like dogs do with people.

Dogs are known to relate human facial expressions and voices to perceive human emotions, but little has been known as to whether horses can do the same.

In the present study to be published in Scientific Reports, Associate Professor Ayaka Takimoto of Hokkaido University, graduate student Kosuke Nakamura of The University of Tokyo, and former Professor Toshikazu Hasegawa of The University of Tokyo, used the expectancy violation method to investigate whether horses cross-modally perceive human emotion by integrating facial expression and voice tone. They also tested whether the familiarity between the horse and the person affected the horse's perception".

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"A team of researchers at the University of Montana has found that fledglings and their parents must negotiate to find the right time for the young birds to leave their nest. In their paper published on the open access site Science Advances, the group describes their study of many types of birds and how they figured out when fledglings should leave the nest.

Many birds build nests to lay their eggs and to hold the young after they hatch until they grow old enough to fly on their own. But how do the baby birds and their parents know when it is time for them to leave? That question, the researchers point out, has not been studied very much. For that reason, they designed and carried out a study to find the answer.

The study consisted of videotaping 11 types of songbirds using a high-speed camera—that allowed them to gain a better understanding of the flying skills of birds. They also watched as the birds grew older and carefully noted the time points at which the young birds left the nest—and how they fared.

The researchers found that there were differences between species—some parents allowed their offspring to stay in the nest longer while others did not. There were also differences in mortality rates between species. Those that left the nest earlier found it tougher going than those that stayed in the nest longer—fewer of them survived because they had not yet developed strong flying skills. On the other hand, young birds that hung around in the nest longer were more likely to attract predators because they were noisier—increasing the likelihood of the whole brood being eaten. The researchers also found that under artificial conditions in which they forced some parentsto keep their young in the nest for a few extra days, the mortality rate was lower—not only did the young birds have more time to develop, they were also protected from predators".

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"University of Alberta paleontologists discovered a new species of marine lizard that lived 70 to 75 million years ago, with its muscle and skin remarkably well preserved.

The fossil is a dolichosaur, a marine lizard related to snakes and mosasaurs. Called Primitivus manduriensis, it was found in Puglia, Italy, and named after the local Manduria variety of red wine grape primitivo.

The fossil was discovered in what was once a shallow water environment. After it died, the lizard fell to the bottom and was covered in sediment, safe from the moving water that would otherwise have scattered its remains. And with no apparent predators around to feed on the carcass, it remained largely intact.

"(The marine lizards) are essentially small, long-bodied animals that look like regular lizards with longer necks and tails," explained Ph.D. student Ilaria Paparella, lead author of the study detailing the discovery. "They have paddle-like hands and feet for swimming but could also move on land."

The fossil is significantly younger than other existing specimens from the group, extending the time range of their existence by about 15 million years.

For Paparella, one of the most interesting things about the specimen was the ability to study the soft tissues, including scales, muscle and skin. She conducted the research as part of her Ph.D. with U of A paleontologist Michael Caldwell, chair of the Department of Biological Sciences.

"There need to be very special conditions for soft tissue to be preserved on a fossil," she explained. "The location where the Primitivus manduriensis was found has a great deal of potential. We hope to get permits from the Italian authorities to conduct further fieldwork.

"This was the first time I've ever had the opportunity to look at the complete picture of a beautifully preserved specimen, right down to the scales," added Paparella. "For living species, scientists use scale patterns and skin for identification. It was unique to be using these techniques to look at a specimen that died 70 million years ago."

The paper, "A New Fossil Marine Lizard With Soft Tissues From the Late Cretaceous of Southern Italy," was published in Royal Society Open Science".

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"Archaeologists at Lund University in Sweden have found carbonised germinated grains showing that malt was produced for beer brewing as early as the Iron Age in the Nordic region. The findings made in Uppåkra in southern Sweden indicate a large-scale production of beer, possibly for feasting and trade.

"We found carbonised malt in an area with low-temperature ovens located in a separate part of the settlement. The findings are from the 400-600s, making them one of the earliest evidence of beer brewing in Sweden," says Mikael Larsson, who specialises in archaeobotany, the archaeology of human-plant interactions.

Archaeologists have long known that beer was an important product in ancient societies in many parts of the world. Through legal documents and images, it has been found, for example, that beer was produced in Mesopotamia as early as 4000 BCE. However, as written sources in the Nordic region are absent prior to the Middle Ages (before ca 1200 CE), knowledge of earlier beer production is dependent on botanical evidence.

"We often find cereal grains on archaeological sites, but very rarely from contexts that testify as to how they were processed. These germinated grains found around a low-temperature oven indicate that they were used to become malt for brewing beer," says Mikael Larsson.

Beer is made in two stages. The first is the malting process, followed by the actual brewing. The process of malting starts by wetting the grain with water, allowing the grain to germinate. During germination, enzymatic activities starts to convert both proteins and starches of the grain into fermentable sugars. Once enough sugar is formed, the germinated grain is dried in an oven with hot air, arresting the germination process. This is what happened in the oven in Uppåkra.

"Because the investigated oven and carbonised grain was situated in an area on the site with several similar ovens, but absent of remains to indicate a living quarter, it is likely that large-scale production of malt was allocated to a specific area on the settlement, intended for feasting and/or trading," explains Mikael Larsson".

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"Deep in the night in muddy African rivers, a fish uses electrical charges to sense the world around it and communicate with other members of its species. Signaling in electrical spurts that last only a few tenths of a thousandth of a second allows the fish to navigate without letting predators know it is there. Now scientists have found that the evolutionary trick these fish use to make such brief discharges could provide new insights, with a bearing on treatments for diseases such as epilepsy.

In a new paper in the journal Current Biology, scientists led by a team at The University of Texas at Austin and Michigan State University outline how some fish, commonly referred to as baby whales, have developed a unique bioelectric security system that lets them produce incredibly fast and short pulses of electricity so they can communicate without jamming one another's signals, while also eluding the highly sensitive electric detection systems of predatory catfish."

In a specialized electric organ near the tail, weakly electric fish, like the baby whales, possess a protein that also exists in the hearts and muscles of humans. The electrical pulses generated through this protein, called the KCNA7 potassium ion channel, last just a few tenths of a thousandth of a second, and some electric fish have adapted to discriminate between timing differences in electrical discharges of less than 10 millionths of a second.

"Most fish cannot detect electric fields, but catfish sense them. The briefer electric fish can make their electric pulse, the more difficult it is for catfish to track them," said Harold Zakon, a professor in the departments of Integrative Biology and Neuroscience.

The team identified a negatively charged patch in the KCNA7 protein that allows the channel in the electric fish to open quickly and be more sensitive to voltage, allowing for the extremely brief discharges".

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"Parasites which are passed on via the food chain often influence the behaviour of their host to their own benefit. One example of this is the tapeworm Schistocephalus solidus, which makes three-spined sticklebacks behave "carelessly". The infected fish venture more often into open waters, making themselves easier prey for piscivorous birds, e.g. kingfishers. This is just what the tapeworm wants because it reproduces in the bird's intestines. A team of evolutionary biologists around Dr. Jörn Peter Scharsack at the University of Münster (Germany) have now demonstrated for the first time that the tapeworm not only influences the behaviour of the infected fish - indirectly, it can also induce equally risky behaviour in other healthy fish in the group. The study is published in the current issue of the journal Proceedings of the Royal Society B.

In laboratory experiments, the researchers demonstrated that in schools of stickleback in which the number of infected fish exceeds that of healthy fish, this healthy minority imitates the changed behaviour of the infected members of their group.

"The reason for this 'wrong' decision on the part of the non-infected sticklebacks presumably has something to with shoaling behaviour," says Jörn Scharsack. "The urge to remain in the group is stronger than exercising caution against any attack by a bird independently." The other way round, however, it is different. The infected fish display risk-friendly behaviour in any case and do not take their lead from the cautious behaviour of the healthy fish when these are in the majority.

The researchers suspect that, in the wild, the ability of the parasite to have an indirect influence on the behaviour of healthy sticklebacks could also have an effect on stickleback and bird populations. More birds could be lured, for example, because more fish means more attractive prey. The predators' urge to eat fish could thus increase, and ultimately more tapeworm could get into the birds' intestines and reproduce there".

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"It's a mystery how cleaner shrimp partner with would-be fish predators -- sometimes even climbing in their mouths -- without getting eaten. A new study reveals how the shrimp convinces fish not to eat them, and the fish conveys that it's a friend and not a foe".
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"In a pilot study, crystalline particles of titanium dioxide -- the most common white pigment in everyday products ranging from paint to candies -- were found in pancreas specimens with Type 2 diabetes, suggesting that exposure to the white pigment is associated with the disease".
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"The Himalayan Range includes some of the youngest and most spectacular mountains on Earth, but the rugged landscape that lends it the striking beauty for which it is known can also keep scientists from fully understanding how these mountains formed. "We know more about the rocks on parts of Mars than we do about some of the areas in the Himalaya," said Dr. Alka Tripathy-Lang.

"Many researchers have done extraordinary geologic mapping in this rugged region, but the fact is that some places are just completely inaccessible because of topography, elevation, or geopolitical issues. The rocks in those areas are an important piece of the tectonic puzzle and are important for understanding the way the region evolved," said Dr. Wendy Bohon. "The tools we used, originally developed for mapping rocks on Mars, were a way to safely access information about the rocks in the Himalayas."

Bohon and colleagues worked with researchers at the Mars Space Flight Facility at Arizona State University to use data from the Earth orbiting satellite Terra in the same way planetary geologists have been using data from the Mars orbiting satellite Odyssey.

The researchers relied on the fact that every mineral has a unique spectral "signature," where some parts of the thermal infrared spectrum are absorbed and some parts are reflected. Rocks are made of different combinations of minerals, so when all of these mineral signatures are combined, they reveal the rock type. To easily distinguish between different kinds of rocks the researchers translated these signals into red/green/blue imagery, which results in a distinguishable color for each rock type that can be used to map the distribution of rocks throughout the region.

To double-check that the colors they're mapping are truly the rock type predicted by the imagery, the researchers took hand samples from accessible locations in the study area to the laboratory and measured the spectral signatures of each rock using a thermal emission spectrometer. Then they compared these laboratory signatures to those collected from the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) instrument on the Terra satellite. They matched. "There is some variation between the lab and ASTER spectral signatures due to different factors like weathering and the averaging area, but overall the match between them was surprisingly consistent," said Tripathy-Lang".

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