It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Saturday, October 24, 2020
HEY KENNEY;
Fiat Chrysler to invest in electric car production in Canada
The company has agreed to invest up to Can$1.5 billion (US$1.1 billion) in southern Ontario's Windsor plant.
Fiat Chrysler (FCA) has committed to a multi-year investment in assembling electric vehicles in Canada and to add up to 2,000 new jobs, a union representing some of the carmaker's workers announced Thursday.
The company has agreed to invest up to Can$1.5 billion (US$1.1 billion) in southern Ontario's Windsor plant as part of a tentative three-year deal with union Unifor, the group's national president Jerry Dias said in a statement.
Under the deal, Fiat Chrysler's investment would outfit the factory to assemble plug-in hybrids and battery-powered vehicles, with at least one new model in 2025, he added.
Up to 2,000 jobs would be added to the Windsor plant in 2024, according to the union, which comes after roughly 1,500 positions were cut at the factory earlier this year.
The Brampton assembly plant would also see Can$50 million in investment, which woud allow additional models to be produced there.
Workers must still ratify the deal through a virtual vote set for Sunday and Monday.
Fiat Chrysler (FCA) has agreed to invest up to Can$1.5 billion (US$1.1 billion) in southern Ontario's Windsor plant as part of a tentative three-year deal with union Unifor, the group's national president Jerry Dias said.
This tentative deal is based on the one struck with Ford workers in Canada and includes a five percent pay bump. Unifor plans to launch talks with General Motors next week to renew their deal. Prime Minister Justin Trudeau's government and the province of Ontario announced last week investments of Can$295 million each in a Ford factory billed as the largest electric vehicle plant in North America.
The three large North American groups as well as Japanese carmakers Toyota and Honda have a total of some 44,000 workers on assembly lines in Ontario, according to Unifor.
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Copyright AFP. All rights reserved.
Translation tools, air purifiers: Face masks go high-tech As masks become the norm worldwide, tech companies are rolling out weird and wonderful models to both guard against infection and cash in on a growing trend.
By Catherine Lai, with Harumi Ozawa in Tokyo
October 21, 2020
From monitoring vital signs to filtering filthy air and even translating speech into other languages, the coronavirus-fuelled boom in mask-wearing has spawned an unusual range of high-tech face coverings.
As masks become the norm worldwide, tech companies and researchers are rolling out weird and wonderful models to both guard against infection and cash in on a growing trend.
Tech companies are looking to cash in on the growing trend of mask-wearing while also helping guard against coronavirus. Photo: AFP / Roslan RAHMAN
One of the wackiest comes from Japan, where start-up Donut Robotics has created a face covering that helps users adhere to social distancing and also acts as a translator.
The "C-Face" mask works by transmitting a wearer's speech to a smartphone via an app, and allows people to have a conversation while keeping up to 10 metres (32 feet) apart.
"Despite the coronavirus, we sometimes need to meet directly with each other," Donut Robotics chief executive Taisuke Ono told AFP.
Taisuke Ono's start-up Donut Robotics has created a mask that helps users adhere to social distancing and also acts as a translator. Photo: AFP / Philip FONG
The lightweight silicone device could have immediate benefits for people such as doctors who want to communicate with patients from a distance, the company says.
It can translate speech from Japanese into English, Korean and other languages -- a function that will become more useful once travel restrictions are eventually eased.
Devices that provide health data or translation services would be of huge benefit to doctors and nurses on the front line of the battle against the virus. Photo: AFP / Roslan RAHMAN
But it does not offer protection from Covid-19 on its own, and is designed to be worn over a regular face covering when it goes on sale in February for about 4,000 yen ($40).
Donut Robotics raised nearly 100 million yen ($950,000) via crowdfunding to develop it, a success Ono believes was driven by a desire for innovations to make life easier during the pandemic.
"We may be able to fight the virus with technology, with human wisdom," he said.
A face mask developed in Singapore can provide protection to medical staff and could monitor vital signs of migrant workers in crowded dormitories, where there was a huge spike in infections earlier this year. Photo: AFP / Roslan RAHMAN
Another face mask developed in Singapore is aimed at protecting medics treating Covid-19 patients.
It has sensors that monitor body temperature, heart rate, blood pressure and blood oxygen levels, and relay data to a smartphone via a Bluetooth transmitter.
"Many of these frontline workers will be exposed to patients when they are taking their vital signs," Loh Xian Jun, one of the scientists behind the invention, told AFP.
"This poses a health risk to the nurses, and we wanted to think about a way to reduce such risk."
Its inventors say the device could also monitor vital signs of migrant workers in crowded dormitories, which incubated massive virus outbreaks in the city-state this year.
They hope to trial it in the near future and market it commercially.
For those seeking to combat the effects of pollution in smog-choked cities, South Korea's LG Electronics has developed an air purifier mask.
The futuristic white device, which fits snugly around the wearer's mouth, nose and chin, is equipped with two filters on either side and fans to aid airflow.
The filters are similar to those in the company's home air purifiers, and can block 99.95 percent of harmful particles.
Thousands have already been made available to medical staff and it will also be rolled out in shops in the future, the company says.
Copyright AFP. All rights reserved.
Evo Morales leaves Argentina for Venezuela: report
Morales on Monday signaled his intention to return to Bolivia.
By AFP News October 24, 2020 Bolivia's former president Evo Morales left Argentina for Caracas late Friday in an official Venezuelan aircraft, the official Argentine news agency Telam said.
Morales, who has been in exile in Buenos Aires since December, flew out of Ezeiza international airport at 5:15 pm (2015 GMT) bound for the Venezuelan capital, Telam said.
Local media said the leader of the Movement for Socialism (MAS) was due to return to the Argentine capital on Sunday.
Former Bolivian president Evo Morales, pictured here on October 22, 2020, left Argentina for Venezuela on Friday, a report said
Photo: AFP / JUAN MABROMATA
Morales on Monday signaled his intention to return to Bolivia after his leftist heir Luis Arce's sweeping presidential election victory last weekend.
Bolivia's electoral commission on Friday confirmed Arce's victory, returning the MAS to power just under a year after Morales resigned and fled Bolivia following weeks of protests over his controversial reelection.
Morales, Bolivia's first indigenous president, served for almost 14 years but last year stood for -- and initially won -- an unconstitutional fourth consecutive term. Bolivia's constitution limits a president to two successive terms.
Copyright AFP. All rights reserved.
Colorado fires raze through East Troublesome as evacuations clog highway
SERIOUSLY THAT'S IT'S NAME Cars have jammed the highway in Larimer County as a thick layer of smoke washed over the area and blocked out the sun.
Colorado fires raging through East Troublesome continue to engulf homes and businesses causing residents to evacuate in a frenzy with long lines of cars jamming the highway. The small town of Estes Park was seen crawling with hundreds of residents fleeing the area in a panic, while those who have already fled can only watch their homes burn down on their home security cameras.
The fire, which is located around the area of Grimes Peak on the Arapaho National Forest, has burned more than 170,000 acres of forest land and only 5% of it has been contained. Most residents fleeing their homes in a rush are in shock as evacuations across Grand County are continuously being implemented. Cars are piling up and clogging the highway in Larimer County as a thick layer of smoke washed over the area, blocking out the sun.
According to CNN meteorologist Brandon MIller, the strong winds and the dry weather conditions are part of what fuels the explosive expanse of the fires in Colorado. Forecasts on the weather are predicted to stay the same for the next couple of days with some light rain that could turn into snow over the weekend. This could provide firefighters a much needed window to contain the flames. Currently, about 93% of the West is experiencing a period of drought. Reports from The National Interagency Fire Centre showed that 60 large fires have burned through more than 3.9 million acres across the country.
In a latest update, Incident Commander Noel Livingston said the fire grew and razed through 50,000 acres on Thursday. He said the way the fire has grown is really unheard of in that particular part of the world.
The incident command has put out orders for additional resources to fight the fire while authorities are still conducting investigations on what caused it.
In an interview, a woman who had lost everything was still trying to come to grips on what had happened to her home.
"You think of the craziest things like the Christmas presents you just bought for your grandkids, and the bedrooms you prepared for them. And you never think it's going to happen to you."
REUTERS/The Pike Hotshots/U.S.
Anti-poaching motion sensor recognizes when wildlife is on the run By Nick Lavars October 20, 2020 A baby African elephant on the move fouroaks/Depositphotos
Modern sensors have given conservationists a powerful new tool in the fight against poaching, with the ability to track the whereabouts of endangered animals as they wander through the wild. A new research project at the University of Twente could harness this technology in yet another useful way, by mixing motion sensors with machine learning to recognize when wildlife is responding to a nearby threat.
The work was carried out by University of Twente’s Jacob Kamminga who is a member of a research group developing small, autonomous sensors for a range of applications. Kamminga developed the wildlife motion sensor as part of his PhD, hoping to offer a way of detecting distinct movement patterns in response to the presence of humans.
The sensor is an inertial measurement unit that includes an accelerometer, gryoscope and magnetometer, which can be attached to the animal to gather motion data as it carries out activities. This is analyzed by onboard artificial intelligence, which then classifies the movements and relays them to a mobile network or satellite connection when it detects a sudden change.
Kamminga used the sensor to classify eleven different movement patterns of goats, sheep and horses using mostly what he calls “unlabeled data,” meaning that the sensor only had to be trained on a small set of animal movements. He also found that in most cases, the sensor worked just as well when reduced to a single accelerometer, which made it far more efficient. Using artificial intelligence to analyze animal motion could lead to some interesting possibilities for anti-poaching groups
“I added a gyroscope as well, that measures rotation,” Kamminga says. “This can make it some more accurate, but this comes with a cost. It consumes 100 times more energy than the accelerometer. In most cases, just the accelerometer is accurate enough.”
Using artificial intelligence to analyze animal motion in this way could lead to some interesting possibilities for anti-poaching groups, who could setup the system so they receive alerts when an endangered species is moving in response to a very specific threat. Beyond that, the system could combine with other wildlife tracking tools to assist in overall efforts to preserve biodiversity.
"Linking wild animal movement recorded using sensors with remotely sensed imagery and GIS (geographic information systems) models is promising technology to better understand the ecological requirements of species, as well as inform management and policy decisions with conservation outcomes and biodiversity,” says Professor Andrew Skidmore, who was involved in the work.
Ancient tectonic plate discovered beneath Canada, geologists claim By Michael Irving October 20, 2020
The team used a method called slab unfolding, which allows them to work backwards from the remains of a subducted plate and work out what it looked like on the surface, millions of years ago University of Houston
The face of the Earth has changed drastically over its life, with plates shifting and sinking. Now, geologists at the University of Houston claim to have found the remains of an ancient tectonic plate beneath Canada that was pushed under the surface tens of millions of years ago.
It’s long been known that in the early Cenozoic Era – around 60 million years ago – there were two major tectonic plates, called Kula and Farallon, in the Pacific Ocean off the western coast of North America. But debate has raged about whether they were joined by a third, oddly named Resurrection, which would have since sunk beneath the surface. And now, the geologists on the new study say they’ve found this missing plate.
When plates push against each other, one of them will often end up sliding underneath the other, sinking down into the mantle – a process called subduction. Over time, the intense heat and pressure there will melt it and change its shape. To try to find the remains of the Resurrection plate, the team started by studying existing tomography images of the mantle below North America.
Next, they applied a technique called slab unfolding, which can identify subducted plates, then unfold and stretch them to roughly figure out their original shapes. Using this method, the team mapped out several large chunks of rock, and worked backwards to identify the original plates they came from.
Two of the objects they studied are already known – the Alaska and Cascadia slabs, which are still attached to each other. The Alaska slab sits beneath the Aleutian Islands and is thought to be the remains of the Kula plate, while the Cascadia slab lies under southern California and represents the remains of Farallon.
But intriguingly, the team identified a third slab detached from the others, about 400 to 600 km (250 to 370 miles) below the surface of northern Canada. They call it the Yukon Slab, and when the clock is wound back it appears to fit the calculated shape of the old Resurrection plate. A diagram of the original locations and shapes of the tectonic plates in the Pacific Ocean, off the western coast of North America. The Resurrection plate's existence has been debated, but the new study claims to have found it University of Houston
“When ‘raised’ back to the earth’s surface and reconstructed, the boundaries of this ancient Resurrection tectonic plate match well with the ancient volcanic belts in Washington State and Alaska, providing a much sought after link between the ancient Pacific Ocean and the North American geologic record,” says Jonny Wu, co-author of the study.
The team’s model suggests that the Yukon slab gradually made its way northeast after the Resurrection plate was first subducted some 40 million years ago.
“We believe we have direct evidence that the Resurrection plate existed,” says Spencer Fuston, co-author of the study. “We are also trying to solve a debate and advocate for which side our data supports.”
Cannabis may reduce acute OCD symptoms, but long-term effects unclear By Rich Haridy October 20, 2020
New research from WSU is among the first to investigate real-world uses of cannabis to treat symptoms of OCD TeriVerbickis/Depositphotos
Research from Washington State University (WSU), and published in The Journal of Affective Disorders, is reporting some people find their symptoms of obsessive-compulsive disorder (OCD) dramatically drop after smoking cannabis. The study suggests the improvements may only be beneficial in the short-term, and more research is necessary to understand the long-term effect of cannabis use on OCD.
Despite the broad interest in cannabis’ therapeutic effects over recent years there has been surprisingly little study focusing specifically on the drug’s relationship with OCD. The results from very first placebo-controlled study on the subject, published earlier this year, found smoking cannabis had the same effect on OCD symptoms as a placebo. However, several animal studies have found doses of CBD may inhibit certain compulsive behaviors.
This new WSU study is not a controlled clinical trial, but instead it relies on self-reported user data gathered by a smartphone app called Strainprint. This Canadian app was designed to offer personalized information for patients, enabling real-time tracking of medical symptoms against specific strains of cannabis.
In this case, subjects can report the severity of their OCD symptoms, before and after cannabis use, offering researchers a way to follow the efficacy of cannabis as a treatment in real-time, and in relation to the varying THC or CBD levels from strain to strain. The WSU team has produced three prior studies analyzing Strainprint data, most notably finding many cannabis users self-administer the drug to treat severe headaches and migraines.
The new study tracked data from 87 subjects with OCD symptoms using the Strainprint app. Over 31 months these subjects logged more than 1,800 cannabis sessions, allowing the researchers to infer valuable long-term use data, as well as examining the shorter, more acute effects.
OCD symptoms were divided into three categories (intrusions, compulsions, and anxiety), with each user rating their symptoms from 0 to 10, both before and after a cannabis session. Overall, the study found subjects reported a 60 percent drop in compulsions, a 49 percent drop in intrusions, and a 52 percent drop in anxiety from before to after smoking cannabis.
Reductions in OCD symptoms relating to compulsions and anxiety remained relatively stable over time, but reductions in intrusions seemed to grow smaller with continued cannabis use. The researchers hypothesize a tolerance to the effects of cannabis may build with long-term use.
“The results overall indicate that cannabis may have some beneficial short-term but not really long-term effects on obsessive-compulsive disorder,” explains Carrie Cuttler, corresponding author on the new study. “To me, the CBD findings are really promising because it is not intoxicating. This is an area of research that would really benefit from clinical trials looking at changes in compulsions, intrusions and anxiety with pure CBD.”
The Strainprint app tracks THC and CBD concentrations in particular strains of cannabis, allowing the researchers to effectively investigate whether cannabinoid levels influence symptomatic outcomes. As Cuttler indicates, the study reveals a distinct correlation between higher CBD levels and greater drops in compulsive OCD symptoms.
This finding certainly gels with earlier animal studies investigating compulsive behavior and CBD, however more targeted human trials are necessary to validate them.
The study is clear to note a number of caveats with this kind of self-reported study, particularly referencing what is called the “expectancy effect” whereby the Strainprint users' positive responses are potentially driven by prior expectations about the benefits of CBD in relation to OCD.
Sampling bias is another particular caveat cited in the study, limiting any broad conclusions about the efficacy of cannabis treating OCD symptoms.
“Specifically, it seems likely that the sample predominantly comprises individuals who find cannabis effective in managing their symptoms,” the researchers write in the study. “Individuals who find it ineffective and/or who do not tolerate its side effects would likely stop using cannabis and the app to track such use. This is further supported by evidence of individual differences in the efficacy of cannabis in reducing symptoms.”
None of this means the study is entirely useless. The researchers note the unique nature of the Strainprint app allows for extraordinary insights into real-world uses of cannabis. And despite the self-reported nature of the data, the ability to track the effect of the drug in single users over long periods of time offers researchers novel perspectives.
The ultimate conclusion of the new study is that cannabis may offer those with OCD some level of acute symptomatic relief in the short-term but there is evidence those benefits can diminish over time. And, the long-term effect of cannabis on OCD is still profoundly unclear.
OSIRIS-REx is leaking asteroid samples due to jammed lid
By David Szondy October 23, 2020 T Images confirmed that the sampler head had collected an abundance of material and was leaking NASA V
Images returned by NASA's OSIRIS-REx asteroid explorer have confirmed that the spacecraft's sample collector head is slowly leaking some of the material it gathered from the surface of the asteroid Bennu on October 20, 2020.
When OSIRIS-REx's Touch-And-Go Sample Acquisition Mechanism (TAGSAM) head made contact with Bennu, its one job was to release a blast of nitrogen gas to stir up soil and small rocks, which it would then collect. Since this autonomous operation was completed and the spacecraft withdrew to a safe distance from the asteroid, NASA scientists have been examining images sent back by cameras to determine if the exercise was successful.
It turned out to be a case of good and bad news. The good news is that the TAGSAM head worked perfectly at just the right angle to the asteroid's surface, collecting material to a depth of several centimeters.
The bad news is that, while the apparatus did collect enough material beyond the minimum of 2 oz (60 g) to meet one of the main mission requirements, it turns out that some larger pieces of rock jammed open the mylar flap that forms the lid of the sampler, and soil is slowly leaking out. Asteroid sample material slowly leaking from the sampler head NASA
To prevent more sample material being lost, the mission team has decided to alter the scheduled program to avoid any movement of the spacecraft. Instead of carrying out Saturday's Sample Mass Measurement activity and a course correction burn on Friday, the team will now concentrate on shifting the sample to the Sample Return Capsule (SRC) for safekeeping on the return to Earth.
Meanwhile, the spacecraft is reported to be in good health.
"Bennu continues to surprise us with great science and also throwing a few curveballs," says Thomas Zurbuchen, NASA’s associate administrator for science. "And although we may have to move more quickly to stow the sample, it’s not a bad problem to have. We are so excited to see what appears to be an abundant sample that will inspire science for decades beyond this historic moment."
Orono, Maine -- The Falkland Islands are a South Atlantic refuge for some of the world's most important seabird species, including five species of penguins, Great Shearwaters, and White-chinned Petrels. In recent years, their breeding grounds in the coastal tussac (Poa flabellata) grasslands have come under increasing pressure from sheep grazing and erosion. And unlike other regions of the globe, there has been no long-term monitoring of the responses of these burrowing and ground nesting seabirds to climate change.
A 14,000-year paleoecological reconstruction of the sub-Antarctic islands led by University of Maine researchers has found that seabird establishment occurred during a period of regional cooling 5,000 years ago. Their populations, in turn, shifted the Falkland Islands ecosystems through the deposit of high concentrations of guano that helped nourish tussac, produce peat and increase the incidence of fire.
This terrestrial-marine link is critical to the islands' grasslands conservation efforts going forward, says Dulcinea Groff, who led the research as a UMaine Ph.D. student in ecology and environmental sciences, and part of a National Science Foundation-funded Interdisciplinary Graduate Education Research Traineeship (IGERT) in Adaptation to Abrupt Climate Change (A2C2). The connection of nutrients originating in the marine ecosystem that are transferred to the terrestrial ecosystem enrich the islands' nutrient-poor soil, thereby making the Falkland Islands sensitive to changes in climate and land use.
The terrestrial-marine linkage in the Falkland Islands was the focus of Groff's dissertation in 2018.
"Our work emphasizes just how important the nutrients in seabird poop are for the ongoing efforts to restore and conserve their grassland habitats. It also raises the question about where seabirds will go as the climate continues to warm," says Groff, who conducted the research in the Falkland Islands during expeditions in 2014 and 2016 led by Jacquelyn Gill, an associate professor of paleoecology and plant ecology in the UMaine Climate Change Institute.
"Our 14,000-year record shows that seabirds established at Surf Bay during cooler climates. Seabird conservation efforts in the South Atlantic should be prepared for these species to move to new breeding grounds in a warmer world, and those locations may not be protected," says Groff, who is now a postdoctoral research scientist at the University of Wyoming.
The UMaine expedition team, which included Kit Hamley, then a master's student in Quaternary studies and a Climate Change Institute Fellow, collected a 476-centimeter peat column from Surf Bay, East Falkland. The 14,000-year record revealed in the undecomposed tussac leaves of the peat column "captures the development of a terrestrial-marine linkage that supports some of the most important breeding colonies of seabirds in the Southern Ocean today," according to the research team, which published its findings in the journal Science Advances.
The absence of seabirds at the East Falklands site prior to 5,000 years ago suggests that seabirds may be sensitive to warmer mediated sea surface temperatures, which can impact their food supply, according to the research team. With a warming South Atlantic today, the question is whether the Falkland Islands, about 300 miles east of South America, will continue to be a seabird breeding "hot spot."
"Our work suggests that as the Southern Ocean continues to warm in the coming decades, the Falkland Islands seabird communities may undergo abrupt turnover or collapse, which could happen on the order of decades," according to the research team, which, in addition to Groff, Hamley (now a UMaine doctoral student) and Gill, involved Trevor Lessard and Kayla Greenawalt of UMaine, Moriaki Yasuhara of the University of Hong Kong, and Paul Brickle of the South Atlantic Environmental Research Institute, all co-authors on the American Association for the Advancement of Science journal article.
The Falkland Islands are at the boundary of a number of potential climate drivers, note the researchers. And P. flabellata peatlands have the world's highest accumulation rates, "providing an unusually high-resolution record capable of recording abrupt change" -- preserved charcoal, seabird guano and pollen data that can be used to analyze fire history, seabird population abundance and vegetation composition, respectively.
In the Falklands, where there are no native mammals or trees, settlers introduced sheep in the 17th century. Today, residents make their livelihoods from fishing, sheep farming and tourism.
The 14,000-year record from East Falkland revealed that for 9,000 years before the arrival of seabirds, the region was dominated by low levels of grasses, a heathland of ferns and dwarf Ericaceous shrubs. About 5,000 years ago, the researchers say, an "abrupt transition" appears to occur. Concentrations in bio-elements such as phosphorus and zinc increase. Grass pollen accumulation rates skyrocket, indicating the establishment of tussac grasslands within 200 years of the establishment of seabird colonies on the island. Also found in the core: increased accumulation rates of peat and charcoal.
It's clear that the addition of seabird populations bringing nutrients from the marine environment to the island drove changes in the terrestrial plant community structure, composition and function, according to the researchers, as well as increased fire activity and nutrient cycling.
What remains unclear is what drove the abrupt ecosystem shift, says Gill, one of the world's leading authorities on paleo-ecosystems, including the impacts of climate change and extinction, and the geographical distribution of living things through space and time.
"We know seabirds arrived at Surf Bay during a time when the climate was becoming cooler in the South Atlantic, though we still don't know for sure what it was they were tracking. We also don't know where these birds took refuge when climates were warmer, and that's concerning as the South Atlantic gets hotter into the future," says Gill, an NSF CAREER researcher who most recently was named a 2020 Friend of the Planet by the National Center for Science Education.
"Our study is also a powerful reminder of why we need to understand how different ecosystems are connected as the world warms," says Gill. "We know that many seabirds in the South Atlantic rely on these unique coastal grasslands, but it turns out that the grasses also depend on the nutrients seabirds provide. Because they rely on ecosystems in the ocean and on land for their survival, seabirds are really good sentinels of global change. We just don't have good long-term monitoring data for most of these species, so we don't know enough about how sensitive they are to climate change. The fossil record can help us fill in the gaps."
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DNA in fringe-lipped bat poop reveals unexpected eating habits
Poop is full of secrets. For scientists, digging into feces provides insights into animal diets and is particularly useful for understanding nocturnal or rare species. When animals eat, prey DNA travels all the way through animal digestive tracts and comes out again. Poop contains very precise information about the prey species consumed. At the Smithsonian Tropical Research Institute (STRI), a team explored the eating habits of the fringe-lipped bat (Trachops cirrhosus) by examining its poop.
Bats hunt at night. This makes it challenging to observe their foraging behavior in nature. Analyzing DNA traces in bat guano offers a more specific way to explore how bats feed in the wild and to study how bat behavior changes depending on their eating habits.
"Because bats forage at night, and in the dense forest, you can't observe what they are eating the way you can with a diurnal bird or mammal," said Patricia Jones, former STRI fellow, assistant professor of biology at Bowdoin College and main author of the study. "It feels so momentous, therefore, to have a glimpse into the diet of this species that we thought we knew so much about, to discover they are eating prey we had no idea were part of their diet."
The fringe-lipped bat, also known as the frog-eating bat, is well adjusted to hunting frogs. The bats' hearing is adapted to their low-frequency mating calls, and their salivary glands may neutralize the toxins in the skin of poisonous prey. Fringed-lipped bats also feed on insects, small reptiles or birds and other bats. Researchers knew that these bats often find their prey by eavesdropping on mating calls, but it was unknown if they could find prey that was silent.
As expected, most of the DNA recovered from the poop samples in the study belonged to frog species and plenty of lizards, but researchers also found evidence that the bats were eating other bats and even a hummingbird. In additional experiments, wild-caught fringe-lipped bats exposed to recordings of prey sounds and stationary prey models were able to detect silent, motionless prey, as well as prey that made sounds. This led researchers to conclude that the fringe-lipped bat is more capable of locating prey by echolocation than previously thought.
"This is interesting because we didn't know that these bats were able to detect silent, still prey," said May Dixon, STRI fellow, doctoral student at the University of Texas at Austin and co-author of the study. "Detecting silent, still prey in the cluttered jungle is thought to be a really hard task for echolocation. This is because when the bats echolocate in the jungle, the echoes of all the leaves and branches bounce back along with the echoes of their prey, and they 'mask' the prey."
These results may offer a new line of research on the sensory abilities and foraging ecology of T. cirrhosus. It also adds to a growing body of work that suggests that, in the tropics, bats may be important nocturnal predators on sleeping animals like birds. The team also found unexpected frog species among its common prey.
"We found T. cirrhosus were often eating frogs in the genus Pristimantis," Jones said. "I think this will open new avenues of research with T. cirrhosus, because Pristimantis call from the canopy and their calls are hard to localize, so if T. cirrhosus are consuming them it means that they are foraging differently than we understood before."
Going forward, this novel combination of dietary DNA analysis with behavioral experiments may be used by other ecologists interested in the foraging behaviors of a wide range of animal species.
"It's really exciting to see the doors that open when animal behavior is combined with metabarcoding," said STRI staff scientist Rachel Page. "Even though we have studied Trachops intensely for decades, we actually know very little about its behavior in the wild. It was completely surprising to see prey items show up in the diet that we never anticipated, such as frog species whose mating calls seemed to lack acoustic parameters helpful for localization and, more surprising, prey that it seems the bats must have detected by echolocation alone, like hummingbirds. This work makes us rethink the sensory mechanisms underlying this bat's foraging behavior, and it opens all kinds of new doors for future questions."
Most of the DNA recovered from the poop samples in the study belonged to frog species and plenty of lizards, but researchers also found evidence that the bats were eating other bats and even a hummingbird.
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Members of the research team are affiliated with STRI, Bowdoin College, SWCA Environmental Consultants and the University of Texas at Austin. Research was funded by the Smithsonian, the National Science Foundation DDIG #1210655 and a P.E.O. Scholar Award.
The Smithsonian Tropical Research Institute, headquartered in Panama City, Panama, is a unit of the Smithsonian Institution. The institute furthers the understanding of tropical biodiversity and its importance to human welfare, trains students to conduct research in the tropics and promotes conservation by increasing public awareness of the beauty and importance of tropical ecosystems.