Friday 15 May 2020

Rhino killed as poaching attempts increase amid India virus lockdown

MAY 11, 2020
A rare one-horned rhino has been killed as poaching attempts increase in one of India's best-known national parks during the coronavirus lockdown, officials said Sunday.

The lack of vehicles on the highway near Kaziranga National Park in Assam state—home to the world's biggest population of one-horned rhinos—amid the lockdown has seen animals move towards the boundaries, making them vulnerable to poachers.

"It is suspected that the rhino was killed at least two to three days ago," the park's director P. Sivakumar told AFP, adding that the rhino's horn was also missing.

Hunters can earn as much as $150,000 for one rhino horn or around $60,000 per kilo on a black market according to media reports, serving foreign demand for its use in traditional Chinese medicine.

"We have also recovered eight rounds of empty cartridge of AK 47" automatic rifle, Sivakumar said.

The rhino carcass was found near a water body inside the park, he said, adding that it was a confirmed poaching incident.

Officials said it was the first poaching case in the UNESCO-listed heritage site in a year. Previous years had seen numerous poaching incidents.

Humpback whales may risk collision with vessels in the Magellan Strait

MAY 14, 2020

Every summer (November-April), the Magellan Strait in the southwestern part of Chile becomes a popular feeding area for migrating humpback whales (Megaptera novaeangliae). The narrow strait is also a heavily used shipping route. A new study by scientists at the Smithsonian Tropical Research Institute (STRI) and collaborating institutions tracked and modelled the movement of individual whales in order to evaluate the potential of vessel collisions and provide policy recommendations for the protection of whale species.

Humpback whales have the longest migratory journeys of any mammal on Earth. The Southern Hemisphere population spends its summer months feeding in the Antarctic and Chile and their winters in the warmer tropical Pacific waters of northern South America and Central America, as far as Nicaragua. Their movements often overlap with boat traffic and may put them at risk of collision, leading to injury or death. Years ago, STRI researcher Héctor M. Guzmán led a study that resulted in international regulations to separate vessel traffic from whale routes near the Panama Canal and in southern Costa Rica, which drastically reduced collision rates in the breeding areas.

"Designing and implementing traffic-separation schemes for Panama and Costa Rica was difficult, because any measures had to be adopted by the International Maritime Organization," said Guzmán, also lead author of the new study in Chile. "It was achieved by having the scientific information explain the whale movements and thanks to the unconditional support of both governments."

The new study, published in Marine Policy, took place in southern Chile, where about 100 humpback whales feed each summer: a population small enough for occasional ship strikes to have important consequences. By tagging and tracking 25 individuals over different years and comparing their movements with available records of vessels traversing the Strait, the team found that, on average, each whale was near a ship about seven times per season. Due to the detailed tracking records of multiple whales, the researchers were able to show that individual animals differed enormously in how often they encountered ships: from less than one to as many as 18 encounters per season.

Malaria mosquitoes eliminated in lab by creating all-male populations

MAY 12, 2020

by Hayley Dunning, Imperial College London

A modification that creates more male offspring was able to eliminate populations of malaria mosquitoes in lab experiments.

A team led by Imperial College London spread a genetic modification that distorts the sex ratio through a population of caged Anopheles gambiae mosquitoes using 'gene drive' technology.

The team's modification causes mosquitoes to produce more male offspring, eventually leading to no females being born and a total collapse in the population. This represents the first successful sex-distorter gene drive ever created, a goal for scientists as these modifications are expected to be extremely effective at controlling natural mosquito populations.

There were 228 million cases of malaria in 2018, and 405,000 deaths, with new interventions needed to move towards malaria eradication. There are around 3500 species of mosquito worldwide, of which only 40 related species can carry malaria. The team's modification was applied to Anopheles gambiae mosquitoes, the main malaria vector in sub-Saharan Africa.

The hope is that Anopheles gambiae mosquitoes carrying a sex-distorter gene drive would be released in the future, spreading the male bias within local malaria-carrying mosquito populations and causing them to collapse.

As only females bite and take blood meals, only they can pass on malaria, so the modification could have a double effect by biasing the population towards fewer females even before the population collapses.

The lab-based experiments were performed with caged populations of mosquitoes, and more experiments are needed before the team consider releasing any modified mosquitoes in the wild. The results are published today in Nature Biotechnology.

Lead scientist Professor Andrea Crisanti, from the Department of Life Sciences at Imperial, said: "This study represents a key milestone in the long-sought objective to bias the progeny of the human malaria mosquito so that only non-biting males are produced. Having a proven driving sex-distorter opens a new avenue for scientists to develop genetic vector controls of malaria with the aim of eradicating the disease."

Research shows even animals benefit from social distance to prevent disease

MAY 11, 2020

Microorganisms living inside and on our body play a crucial role in both the maintenance of our health and the development of disease. Now researchers at UTSA have uncovered evidence about the importance of maintaining physical distance to minimize the spread of microbes among individuals.

The scientists observed monkeys in the wild to understand what role genetics, diet, social groupings and distance in a social network play when it comes to the microbes found inside an animal's gut.

"Social microbial transmission among monkeys can help inform us about how diseases spread. This has parallels to our current situation in which we are trying to understand how social distancing during the COVID 19 pandemic and future disease outbreaks may influence disease transmission," said Eva Wikberg, an assistant professor in UTSA's Department of Anthropology who studies the interaction between ecology, behavior and genetics in primates.

The gut microbiome refers to all the microorganisms inhabiting the digestive tract, starting with the stomach and ending with the colon. Over the past decade the microbiome has come under more scientific focus because it's believed that an unhealthy gut microbiome can lead to obesity, impaired immune function, weakened parasite resistance and even behavioral changes.

However, researching microbiomes is difficult because of the variation in microbial composition between individuals. One long-standing question is whether this variation is driven by genetic makeup, diets or social environments.

This research inquiry has been especially hard in wild populations because of the lack of detailed data necessary to tease apart the myriad factors that shape the microbiome.

Thursday 14 May 2020

Learning what's dangerous is costly, but social animals have a way of lowering the price

MAY 12, 2020

by Champalimaud Centre for the Unknown

What would you do if the person standing next to you suddenly screamed and ran away? Would you be able to carry on calmly with what you're doing, or would you panic? Unless you're James Bond, you're most likely to go for the second option: panic.

But now imagine another scenario: While out on the street, the person walking in front of you suddenly freezes—she stops moving and becomes perfectly still. What would you do?

"Here, the answer becomes more tricky," says Marta Moita, head of the Behavioral Neuroscience Lab at the Champalimaud Centre for the Unknown, in Lisbon, Portugal. "Even though freezing is one of the three basic instinctive defense behaviors [along with fight and flight], animals don't instinctively know that when others freeze, they are actually responding to a threat."

For social animals such as ourselves, being able to tell if a group member senses a threat can be a matter of life and death. How does this learning happen? To find an answer to this question, Moita and her team engaged in a series of studies. Their most recent findings are presented in two scientific articles, one that was published today (May 12th) in the journal PLOS Biology and another published a few months ago in Current Biology. Together, their results reveal a mechanism by which animals acquire fear of freezing and outline the neural circuitry that underlies the expression of that fear.

Desert mystery: Why have pronghorn antelope returned to Death Valley

MAY 13, 2020
by Louis Sahagun

More than a century after railroads, ranchers and hunters vanquished their ancestors, pronghorn antelope are returning to this unforgiving expanse of desert along the California-Nevada border.

A photo of a lone male and a harem of five does shared on Death Valley's Facebook page in late April was only the latest indication that the American pronghorn, North America's land speed champion, may be extending its migratory range into the Mojave Desert once again from cooler seas of sage nearly 100 miles to the north and east.

"It's not all gloom and doom, woohoo!" the nonprofit National Parks Conservation Association announced to wildlife advocates nationwide. "If nothing else, enjoy the feel-good photo and I hope you're doing well."

The pronghorn's reappearance here is a bit of a mystery, as most animal species are making tracks for higher and cooler elevations as the climate warms. Some say the interloping antelope could find themselves in dire straits once summer heat blankets the park.

Along with the recent photo, park officials noted: "Pronghorn may be some of the newest residents to our park! While on patrol, rangers have recently spotted a herd of these quick-footed animals and at least one lone male exploring the park, likely the result of a migration that has been years in the making.

"While pronghorn have been witnessed in the park on occasion for the past two years," they added, "this increase in their presence suggests these graceful creatures may become long-term residents of the valley."

Genome of beloved sea otter Gidget now available for browsing

MAY 13, 2020

A sea otter genome browser—featuring the Monterey Bay Aquarium's beloved Gidget—is now available to the public. The visualizable genome for the Southern sea otter, Enhydra lutris nereis, comes following work by the National Center for Biotechnology Information (NCBI) and UC Santa Cruz software bioinformaticians to make available the first complete southern sea otter genome sequenced by researchers at the University of California Los Angeles.

The release of the sea otter genome on the UCSC Genome Browser is the result of a study by UCLA scientists and co-authors that examined the evolutionary history and genetic diversity of sea otters, and found that sea otters have low genetic diversity. In their investigations, the researchers sequenced Gidget's genetic code—her genome.

A genome assembly is the entirety of the species' genetic code, produced after chromosomes have been fragmented, the genetic code in those fragments has been written down—or sequenced—and the resulting sequences have been put back together—or assembled.

The sea otter's low level of genetic diversity is similar to other threatened species, such as the cheetah and Tasmanian devil, said investigator Annabel Beichman, a UCLA graduate student in ecology and evolutionary biology.

Moths have a secret but vital role as pollinators in the night

MAY 12, 2020

Moths are important pollen transporters in English farmland and might play a role in supporting crop yields, according to a new UCL study.

The research, published in Biology Letters, shows that moth pollen transport networks are larger and more complex than networks for daytime pollinators.

The team found that moths transport pollen from a high number of plants also visited by bees, butterflies and hoverflies, but also interacted with plants not commonly visited by these insects.

The study also shows that pollen transport occurs most frequently on the moth's ventral thorax (chest), rather than on the proboscis (tongue), allowing it to be easily transferred to other plants.

Lead author of the study, Dr. Richard Walton (UCL Geography) said: "Nocturnal moths have an important but overlooked ecological role. They complement the work of daytime pollinators, helping to keep plant populations diverse and abundant. They also provide natural biodiversity back-up, and without them many more plant species and animals, such as birds and bats that rely on them for food, would be at risk.

"Previous studies of pollen transport among settling moths have focused on their proboscis. However, settling moths sit on the flower while feeding, with their often distinctly hairy bodies touching the flower's reproductive organs. This happy accident helps pollen to be easily transported during subsequent flower visits."

This pivotal study comes at the time as moth populations are experiencing steep declines across the globe, with worrying implications that we may be losing critical pollination services at a time when we are barely beginning to understand them.

Dr. Jan Axmacher (UCL Geography) said: "In recent decades, there has been a lot of science focus on solitary and social bees driven by concerns about their dramatic decline and the strong negative effect this has had on insect-pollinated crop yields.

Wednesday 13 May 2020

New test identifies lobster hybrids

Date: May 11, 2020
Source: University of Exeter

Scientists have developed a test that can identify hybrids resulting from crossbreeding between European and American lobsters.

American lobsters have occasionally escaped or been released into European waters after being imported for the seafood market.

Experts have long feared they could threaten European lobsters by introducing disease or establishing as an invasive species.

Hybridisation -- when a "pure" species is threatened at a genetic level via interbreeding with a different but related species -- had been less of a concern because lab studies suggested European and American lobsters were reluctant to mate.

However, when an American lobster female was found bearing eggs in a fjord in Sweden, University of Exeter researchers tested the offspring and found they were "clearly distinct" from both European and American lobsters.

"We had just developed a genetic test for seafood traceability that could separate any American lobsters mislabelled as more expensive European equivalents once they've been cooked and shell colouration is no longer a useful indicator of the species," said Dr Charlie Ellis, of the University of Exeter.

"What we found when we tested these offspring is that they came out exactly in the middle of this separation -- half American and half European -- so these lobsters were hybrids."

This has potentially concerning implications for the lobster industry and conservation efforts, and Dr Ellis says further research is required to assess the extent of the threat.

Flying foxes in South Australia exposed to zoonotic viruses

Date: May 11, 2020
Source: University of Adelaide

University of Adelaide researchers have found that South Australia's population of Grey-headed flying foxes, which took up residence in 2010, has been exposed to a number of viruses, including Hendra virus that can be transmitted to humans via horses. But they have not found evidence of exposure to Australian bat lyssavirus.

The research, published today in PLOS ONE, details three years of research into the local flying fox population and their exposure to paramyxoviruses (Hendra, Cedar and Tioman) and a rhabdovirus (Australian bat lyssavirus).

Hendra virus and Australian bat lyssavirus are classified as zoonotic viruses. Hendra virus for example can be transmitted to horses and then to humans by airborne droplets causing acute respiratory diseases and death. In the case of Australian bat lyssavirus, humans and other animals need to be bitten or scratched by a carrier. The risks posed by Hendra virus are extremely low with only seven cases in humans, all of whom had been in contact with infected horses, never directly from bats.

Dr Wayne Boardman from the University of Adelaide's School of Animal and Veterinary Sciences says given the Grey-headed flying foxes are known carriers of viruses, they wanted to understand if the local population of flying foxes had been exposed to them.

"Grey-headed flying foxes are essential ecosystem service providers contributing to large-scale pollination and seed dispersal and are a nationally threatened species," Dr Boardman said.

"They have this extraordinary ability to be infected with viruses but don't show any ill effects, except for one virus; the Australian bat lyssavirus. It's important to understand what risks they pose to humans.

Extinction of threatened marine megafauna would lead to huge loss in functional diversity

Date: April 17, 2020
Source: Swansea University

In a paper published in Science Advances, an international team of researchers have examined traits of marine megafauna species to better understand the potential ecological consequences of their extinction under different future scenarios.

Defined as the largest animals in the oceans, with a body mass that exceeds 45kg, examples include sharks, whales, seals and sea turtles.

These species serve key roles in ecosystems, including the consumption of large amounts of biomass, transporting nutrients across habitats, connecting ocean ecosystems, and physically modifying habitats.

Traits, such as how large they are, what they eat, and how far they move, determine species' ecological functions. As a result, measuring the diversity of traits allows scientists to quantify the contributions of marine megafauna to ecosystems and assess the potential consequences of their extinction.

The team of researchers -- led by Swansea University's Dr Catalina Pimiento -- first compiled a species-level trait dataset for all known marina megafauna to understand the extent of ecological functions they perform in marine systems.

Then, after simulating future extinction scenarios and quantifying the potential impact of species loss on functional diversity, they introduced a new index (FUSE) to inform conservation priorities.

Monday 11 May 2020

Arctic Edmontosaurus lives again: A new look at the 'caribou of the Cretaceous'

Date: May 6, 2020
Source: Perot Museum of Nature and Science

A new study by an international team from the Perot Museum of Nature and Science in Dallas and Hokkaido University and Okayama University of Science in Japan further explores the proliferation of the most commonly occurring duck-billed dinosaur of the ancient Arctic as the genus Edmontosaurus. The findings also reinforce that the hadrosaurs -- known as the "caribou of the Cretaceous" -- had a huge geographical distribution of approximately 60 degrees of latitude, spanning the North American West from Alaska to Colorado.

The scientific paper describing the find -- titled "Re-examination of the cranial osteology of the Arctic Alaskan hadrosaurine with implications for its taxonomic status" -- has been posted in PLOS ONE, an international, peer-reviewed, open-access online publication featuring reports on primary research from all scientific disciplines. The authors of the report are Ryuji Takasaki of Okayama University of Science in Japan; Anthony R. Fiorillo, Ph.D. and Ronald S. Tykoski, Ph.D. of the Perot Museum of Nature and Science in Dallas, Texas; and Yoshitsugu Kobayashi, Ph.D. of Hokkaido University Museum in Japan.

"Recent studies have identified new species of hadrosaurs in Alaska, but our research shows that these Arctic hadrosaurs actually belong to the genus Edmontosaurus, an abundant and previously recognized genus of duck-billed dinosaur known from Alberta south to Colorado," said Takasaki.

The report states that anatomical comparisons and phylogenetic analyses clearly demonstrate that attribution of the Alaskan hadrosaurines to a unique genus Ugrunaaluk is inappropriate, and they are now considered as a junior synonym of Edmontosaurus, a hadrosaurines genus previously known from lower latitude North America roughly in between northern Colorado (N40?) to southern Alberta (N53?).

The fossils used for this study were found primarily in the Liscomb Bonebed, Prince Creek Formation of the North Slope of Alaska, the location of the first dinosaur fossils discovered in the Arctic.

The team's research also show that the plant-eating hadrosaurs were taking over parts of North America during the Cretaceous, suggesting that Edmontosaurus was likely an ecological generalist.

"In other words, Edmontosaurus was a highly successful dinosaur that could adapt to a wide variety of environmental conditions," said Fiorillo. "It's not unrealistic to compare them to generalized animals today -- such as mountain sheep, wolves and cougars in terms of their range and numbers -- that also roam greater geographic distributions."

Members of this team also found ties to Kamuysaurus japonicus, a new genus species they discovered near Hokkaido, Japan, and named in 2019.

Virgin birth has scientists buzzing

Researchers discover a gene in honey bees that causes virgin birth

Date: May 7, 2020
Source: University of Sydney

In a study published today in Current Biology, researchers from University of Sydney have identified the single gene that determines how Cape honey bees reproduce without ever having sex. One gene, GB45239 on chromosome 11, is responsible for virgin births.

"It is extremely exciting," said Professor Benjamin Oldroyd in the School of Life and Environmental Sciences. "Scientists have been looking for this gene for the last 30 years. Now that we know it's on chromosome 11, we have solved a mystery."

Behavioural geneticist Professor Oldroyd said: "Sex is a weird way to reproduce and yet it is the most common form of reproduction for animals and plants on the planet. It's a major biological mystery why there is so much sex going on and it doesn't make evolutionary sense. Asexuality is a much more efficient way to reproduce, and every now and then we see a species revert to it."

In the Cape honey bee, found in South Africa, the gene has allowed worker bees to lay eggs that only produce females instead of the normal males that other honey bees do. "Males are mostly useless," Professor Oldroyd said. "But Cape workers can become genetically reincarnated as a female queen and that prospect changes everything."

But it also causes problems. "Instead of being a cooperative society, Cape honey bee colonies are riven with conflict because any worker can be genetically reincarnated as the next queen. When a colony loses its queen the workers fight and compete to be the mother of the next queen," Professor Oldroyd said.

The ability to produce daughters asexually, known as "thelytokous parthenogenesis," is restricted to a single subspecies inhabiting the Cape region of South Africa, the Cape honey bee or Apis mellifera capensis.

Cannibalism helps invading invertebrates survive severe conditions

Date:May 7, 2020
Source:University of Southern Denmark

In a world where movements of non-native animal species are drastically disrupting whole ecosystems and causing economic harm and environmental change, it is becoming increasingly important to understand the features that allow them to colonize new habitats.

A new study, published in Communications Biology, shows that the prolific comb jelly, a marine invertebrate invader from North America that now frequently washes up on Baltic shores, is able to expand their geographical range thanks to the use of its own young as nutrient stores through long and nutrient deprived winters.

As jellies trace their lineage back to the beginning of all animal life, this work furthers the view of cannibalism as a pervasive trait amongst the animal kingdom.

Mysterious success

With their translucent gelatinous bodies, they may not look like much, but the expansion of the comb jelly, Mnemiopsis leidyi, from the east coasts of North and South America to Eurasian coastal waters has wreaked havoc on local environments.

Their success has remained something of a mystery especially as, instead of storing resources before wintering, they seemed to counterproductively invest in massive 'blooms' of offspring unable to survive long and nutrient deprived winters.

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