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News Article | May 15, 2017
Site: news.yahoo.com

Timing is everything for migratory songbirds chirping away in North America's trees. If they arrive too late, they'll get only the scraps of spring's insect buffet. Plus, the best nesting spots and mates will be taken, leaving them with lackluster prospects for making baby birds. Arrive too early, and they'll face a hostile winter chill. Yet climate change is making it harder for birds to get it right. Spring is arriving earlier in the eastern states and later in the west, disrupting the timing of dozens of songbird species, a new study found. SEE ALSO: The atmosphere has forgotten what season it is in the U.S. As birds struggle to settle in and lay eggs, it could create a "domino effect" that threatens the survival of many popular backyard species, U.S. and Canadian researchers said in a study published Monday in the journal Scientific Reports. "The long-term concern is that this growing mismatch can lead to population declines," Stephen Mayor, the study's first author and a postdoctoral researcher with the Florida Museum of Natural History at the University of Florida, said in an interview. "Getting the timing right — not too early but not too late — is really important for the birds," he added. Migratory birds that winter in Central and South America take their cues from seasonal changes in daylight, which stay constant from year to year. But the conditions they encounter when they arrive up north are becoming more variable and unpredictable due to rising air temperatures and shifting weather patterns, two effects of human-caused global warming. Nine species in particular are struggling most to get that timing right, the study found. They are: great crested flycatchers, indigo buntings, scarlet tanagers, rose-breasted grosbeaks, eastern wood pewees, yellow-billed cuckoos, northern parulas, blue-winged warblers, and Townsend's warblers. This year, after a mild U.S. winter, spring weather arrived more than three weeks earlier than usual in some places. The date of "first leaf," a temperature-based calculation of when dormant vegetation shows signs of life, came much earlier than the 30-year average, according to a study by World Weather Attribution. Spring is also arriving earlier in three-fourths of the 276 natural resource parks that U.S. scientists examined, resulting in seasonal changes in vegetation such as pollen, seed, and fruit production, a 2016 report found. For the bird study, researchers looked at satellite images from across North America for the period 2001 to 2012. Over that time, plants in the eastern half of the continent put out new leaves — a process called "green-up" — increasingly earlier in the season. In the west, however, green-up typically came later. The team also combed through tens of thousands of bird observations for 48 common songbird species. They wanted to see when those populations first arrived, and whether their arrival coincided with the first signs of spring. Researchers found the gap between green-up and the birds' arrivals grew by an average of more than half a day per year across all 48 species, at a rate of five days per decade. For the nine species in particular, however, the mismatch is growing at double or triple that rate. Mayor said it's still unclear why those nine birds species are far more discombobulated than the rest of the group. "That's something we're trying to tease apart with follow-up research," he said. Still, the outlook might not be entirely dire for songbirds and other avian species.  Previous studies have shown that some birds are shifting the timing of major life events, such as reproduction and laying eggs, in an effort to keep pace with the changing climate. Scientists are watching to see if birds can keep it up long term. "If anything could adapt to climate change, you'd think that birds that migrate thousands of miles could," Mayor said in a press release. WATCH: These bladeless wind generators are economic and bird friendly


News Article | May 15, 2017
Site: phys.org

A growing shift in the onset of spring has left nine of 48 species of songbirds studied unable to reach their northern breeding grounds at the calendar marks critical for producing the next generation of fledglings, according to a paper published today in Nature Scientific Reports. That's because in many regions, warming temperatures are triggering plants to begin their growth earlier or later than normal, skewing biological cycles that have long been in sync. "The birds are trying to keep us with the speed of climate change but they can't…it's just too fast," said Morgan Tingley, assistant professor of ecology and evolutionary biology at the University of Connecticut, and a study author. "They can't adapt quickly enough." The multi-institutional study used data from satellites and citizen scientists to study how quickly the interval between spring plant growth and the arrival of 48 songbird species across North America changed from 2001 to 2012. Researchers found the gap lengthened by over half a day per year across all species on average, a rate of five days per decade—but for some species, the mismatch is growing at double or triple that rate. Nine species were clearly unable to keep up with the shift: great crested flycatchers, indigo buntings, scarlet tanagers, rose-breasted grosbeaks, eastern wood pewees, yellow-billed cuckoos, northern parulas, blue-winged warblers and Townsend's warblers. The study is the first to investigate the increasing mismatch between songbirds' springtime arrival and plant growth at the continental scale and across dozens of species, the researchers said. Previous studies have predicted climate change will drive hundreds of bird species to extinction and greatly reduce the ranges of others. But some are shifting the timing of their major life events, such as reproduction and laying eggs, in an attempt to keep up with the changes. The key question is whether this strategy will work long term, author said Stephen Mayor, a postdoctoral researcher with the Florida Museum of Natural History at the University of Florida. "If anything could adapt to climate change, you'd think that birds that migrate thousands of miles could," he said. "It's much easier for them to move in response to climate conditions than salamanders, for example, or trees." Birds leave their winter homes in Central and South America for the north based on the seasonal shift in hours of daylight, a cue unaltered by climate change. To produce healthy young, they must arrive at their breeding grounds to take advantage of the early-season boom in insects that emerge with springtime plant growth. But as climate change shifts the timing of when plants put out new leaves – a temperature-driven process known as green-up – migrating birds become more likely to reach breeding grounds when temperatures are still frigid and food is scarce or after insect numbers have begun to dwindle. The researchers found green-up is beginning earlier in eastern North America and – surprisingly – later in the West. Birds that breed primarily in eastern temperate forests tended to lag behind while species that breed in western forests reached breeding grounds too early. The rate of change is concerning given predicted accelerating climatic changes, which could mean timing will be more out of sync in the future. "How quickly we can adapt and whether and how much of the natural world, including ourselves, lags behind where we should be in response to climate change is really one of the key challenges," said Tingley. The increased variability in weather conditions that comes with climate change could also compound birds' difficulties in tracking year-to-year changes. A resource that enabled the study's broad-scale investigation of nearly 50 bird species across North America are the tens of thousands of data points contributed by citizen scientists, the researchers said. The so called "citizen scientists" are mainly amateur birdwatchers who enter their observations into the eBIRD database of the Cornell Lab or Ornithology. "As a single scientist no one ever collects data across the scale of a continent, a decade or multiple decades," said Tingley. "The study would not have been possible if it weren't for citizens – non-scientists – that are contributing their observations in their backyards and in their parks so we can actually study what has been happening over an entire continent over more than a decade." Diving deeper into the data to determine whether population numbers of bird species are falling is one of the next steps in the project. "The natural world is very complex," Mayor said. "When you kick it with a big change by altering the climate, different parts of that natural world respond in different ways. We're just beginning to understand the consequences of this grand unnatural experiment." Explore further: Can barnacle geese predict the climate? More information: Stephen J. Mayor et al. Increasing phenological asynchrony between spring green-up and arrival of migratory birds, Scientific Reports (2017). DOI: 10.1038/s41598-017-02045-z


News Article | May 15, 2017
Site: www.sciencedaily.com

New research shows climate change is altering the delicate seasonal clock that North American migratory songbirds rely on to successfully mate and raise healthy offspring, setting in motion a domino effect that could threaten the survival of many familiar backyard bird species. A growing shift in the onset of spring has left nine of 48 species of songbirds studied unable to reach their northern breeding grounds at the calendar marks critical for producing the next generation of fledglings, according to a paper published in Scientific Reports. That's because in many regions, warming temperatures are triggering plants to begin their growth earlier or later than normal, skewing biological cycles that have long been in sync. The result, researchers say, could be a future much like the one Rachel Carson hinted at more than 50 years ago. "It's like 'Silent Spring,' but with a more elusive culprit," said Stephen Mayor, a postdoctoral researcher with the Florida Museum of Natural History at the University of Florida and first author of the study. "We're seeing spring-like conditions well before birds arrive. The growing mismatch means fewer birds are likely to survive, reproduce and return the following year. These are birds people are used to seeing and hearing in their backyards. They're part of the American landscape, part of our psyche. To imagine a future where they're much less common would be a real loss." A multi-institutional team led by Mayor used data from satellites and citizen scientists to study how quickly the interval between spring plant growth and the arrival of 48 songbird species across North America changed from 2001 to 2012. The researchers found the gap lengthened by over half a day per year across all species on average, a rate of five days per decade -- but for some species, the mismatch is growing at double or triple that rate. Nine species were clearly unable to keep up with the shift: great crested flycatchers, indigo buntings, scarlet tanagers, rose-breasted grosbeaks, eastern wood-pewees, yellow-billed cuckoos, northern parulas, blue-winged warblers and Townsend's warblers. While the majority of species studied adjusted their arrival dates, the study suggests the rate of change could be outpacing their efforts. The study is the first to investigate the increasing mismatch between songbirds' springtime arrival and plant growth at the continental scale and across dozens of species, said Mayor, who led the project chiefly at Memorial University of Newfoundland. Previous studies have predicted climate change will drive hundreds of bird species to extinction and greatly reduce the ranges of others. But some are shifting the timing of their major life events, such as reproduction and laying eggs, in an attempt to keep up with the changes. The key question, Mayor said, is whether this strategy will work long term. "If anything could adapt to climate change, you'd think that birds that migrate thousands of miles could," he said. "It's much easier for them to move in response to climate conditions than salamanders, for example, or trees. But because every species relates to another, one of our fears is that climate change can disrupt these relationships between organisms such that their critical life events are not timed optimally, putting them at risk." Birds leave their winter homes in Central and South America for the north based on the seasonal shift in hours of daylight, a cue unaltered by climate change. To produce healthy young, they must arrive at their breeding grounds to take advantage of the early-season boom in insects that emerge with springtime plant growth. But as climate change shifts the timing of when plants put out new leaves -- a temperature-driven process known as green-up -- migrating birds become more likely to reach breeding grounds when temperatures are still frigid and food is scarce or after insect numbers have begun to dwindle. The researchers found green-up is beginning earlier in eastern North America and -- surprisingly -- later in the West. Birds that breed primarily in eastern temperate forests tended to lag behind green-up while species that breed in western forests reached breeding grounds too early. The rate of change is concerning, given predicted accelerating climatic changes, which could mean timing will be more out of sync in the future, said study co-author Rob Guralnick, associate curator of bioinformatics at the Florida Museum. "That's the future many of us will see," he said. "Not every year will plot exactly along that line, but the trend is clear." The increased variability in weather conditions that comes with climate change could also compound birds' difficulties in tracking year-to-year changes. The team is examining why some species of birds seem to adjust to the shifts better than others, Mayor said. A resource that enabled the study's broad scale investigation of nearly 50 bird species across North America are the tens of thousands of data points contributed by citizen scientists, the researchers said. "As more and more birders record their observations, they are creating a density of data that allows us to start from a continental level and zoom down further and further to the ground," Guralnick said. "It's powerful. Whether they know it or not, birders are helping scientists do their work, and they could end up helping birds in the process." The researchers emphasized the complexity of their findings, which vary by species, region and rate of change. Determining conservation risks and the potential for extinction will require looking at the impacts on each species individually, they said. Diving deeper into the data to determine whether population numbers of bird species that are not adapting to the shift in green-up are falling is one of the next steps in the project. "The natural world is very complex," Mayor said. "When you kick it with a big change by altering the climate, different parts of that natural world respond in different ways. We're just beginning to understand the consequences of this grand unnatural experiment."


News Article | May 22, 2017
Site: www.futurity.org

A growing shift in the onset of spring left 9 of 48 species of songbirds in a new study unable to reach their northern breeding grounds at the calendar marks critical for producing the next generation of fledglings. In many regions, warming temperatures are triggering plants to begin their growth earlier or later than normal, skewing biological cycles that have long been in sync. The result, researchers say, could be a future much like the one Rachel Carson hinted at more than 50 years ago. “It’s like Silent Spring, but with a more elusive culprit,” says Stephen Mayor, a postdoctoral researcher with the Florida Museum of Natural History at the University of Florida and first author of the study. “We’re seeing spring-like conditions well before birds arrive. The growing mismatch means fewer birds are likely to survive, reproduce, and return the following year. “These are birds people are used to seeing and hearing in their backyards. They’re part of the American landscape, part of our psyche. To imagine a future where they’re much less common would be a real loss.” Mayor and colleagues used data from satellites and citizen scientists to study how quickly the interval between spring plant growth and the arrival of 48 songbird species across North America changed from 2001 to 2012. The researchers found the gap lengthened by over half a day per year across all species on average, a rate of five days per decade—but for some species, the mismatch is growing at double or triple that rate. Nine species were clearly unable to keep up with the shift: great crested flycatchers, indigo buntings, scarlet tanagers, rose-breasted grosbeaks, eastern wood pewees, yellow-billed cuckoos, northern parulas, blue-winged warblers, and Townsend’s warblers. While the majority of species studied adjusted their arrival dates, the study suggests the rate of change could be outpacing their efforts. The study is the first to investigate the increasing mismatch between songbirds’ springtime arrival and plant growth at the continental scale and across dozens of species, says Mayor, who led the project chiefly at Memorial University of Newfoundland. Previous studies have predicted climate change will drive hundreds of bird species to extinction and greatly reduce the ranges of others. But some are shifting the timing of their major life events, such as reproduction and laying eggs, in an attempt to keep up with the changes. The key question, Mayor says, is whether this strategy will work long term. “If anything could adapt to climate change, you’d think that birds that migrate thousands of miles could,” he says. “It’s much easier for them to move in response to climate conditions than salamanders, for example, or trees. But because every species relates to another, one of our fears is that climate change can disrupt these relationships between organisms such that their critical life events are not timed optimally, putting them at risk.” Birds leave their winter homes in Central and South America for the north based on the seasonal shift in hours of daylight, a cue unaltered by climate change. To produce healthy young, they must arrive at their breeding grounds to take advantage of the early-season boom in insects that emerge with springtime plant growth. But as climate change shifts the timing of when plants put out new leaves—a temperature-driven process known as green-up—migrating birds become more likely to reach breeding grounds when temperatures are still frigid and food is scarce or after insect numbers have begun to dwindle. The researchers found green-up is beginning earlier in eastern North America and—surprisingly—later in the West. Birds that breed primarily in eastern temperate forests tended to lag behind green-up while species that breed in western forests reached breeding grounds too early. The rate of change is concerning, given predicted accelerating climatic changes, which could mean timing will be more out of sync in the future, says coauthor Rob Guralnick, associate curator of bioinformatics at the Florida Museum. “That’s the future many of us will see,” he says. “Not every year will plot exactly along that line, but the trend is clear.” The increased variability in weather conditions that comes with climate change could also compound birds’ difficulties in tracking year-to-year changes. The team is examining why some species of birds seem to adjust to the shifts better than others, Mayor says. A resource that enabled the study’s broad scale investigation of nearly 50 bird species across North America are the tens of thousands of data points contributed by citizen scientists, the researchers say. “As more and more birders record their observations, they are creating a density of data that allows us to start from a continental level and zoom down further and further to the ground,” Guralnick says. “It’s powerful. Whether they know it or not, birders are helping scientists do their work, and they could end up helping birds in the process.” The researchers emphasize the complexity of their findings, which vary by species, region, and rate of change. Determining conservation risks and the potential for extinction will require looking at the impacts on each species individually, they say. Diving deeper into the data to determine whether population numbers of bird species that are not adapting to the shift in green-up are falling is one of the next steps in the project. “The natural world is very complex,” Mayor say. “When you kick it with a big change by altering the climate, different parts of that natural world respond in different ways. We’re just beginning to understand the consequences of this grand unnatural experiment.” Funding from the Natural Sciences and Engineering Research Council of Canada helped support the research, which appears in Scientific Reports. Researchers from Memorial University of Newfoundland, the University of Colorado, the University of Connecticut, Florida International University, Murdoch University, and the Illinois Natural History Survey also contributed to the study.


News Article | May 15, 2017
Site: www.rdmag.com

New research shows climate change is altering the delicate seasonal clock that North American migratory songbirds rely on to successfully mate and raise healthy offspring, setting in motion a domino effect that could threaten the survival of many familiar backyard bird species. A growing shift in the onset of spring has left nine of 48 species of songbirds studied unable to reach their northern breeding grounds at the calendar marks critical for producing the next generation of fledglings, according to a paper published today in Scientific Reports. That's because in many regions, warming temperatures are triggering plants to begin their growth earlier or later than normal, skewing biological cycles that have long been in sync. The result, researchers say, could be a future much like the one Rachel Carson hinted at more than 50 years ago. "It's like 'Silent Spring,' but with a more elusive culprit," said Stephen Mayor, a postdoctoral researcher with the Florida Museum of Natural History at the University of Florida and first author of the study. "We're seeing spring-like conditions well before birds arrive. The growing mismatch means fewer birds are likely to survive, reproduce and return the following year. These are birds people are used to seeing and hearing in their backyards. They're part of the American landscape, part of our psyche. To imagine a future where they're much less common would be a real loss." A multi-institutional team led by Mayor used data from satellites and citizen scientists to study how quickly the interval between spring plant growth and the arrival of 48 songbird species across North America changed from 2001 to 2012. The researchers found the gap lengthened by over half a day per year across all species on average, a rate of five days per decade--but for some species, the mismatch is growing at double or triple that rate. Nine species were clearly unable to keep up with the shift: great crested flycatchers, indigo buntings, scarlet tanagers, rose-breasted grosbeaks, eastern wood-pewees, yellow-billed cuckoos, northern parulas, blue-winged warblers and Townsend's warblers. While the majority of species studied adjusted their arrival dates, the study suggests the rate of change could be outpacing their efforts. The study is the first to investigate the increasing mismatch between songbirds' springtime arrival and plant growth at the continental scale and across dozens of species, said Mayor, who led the project chiefly at Memorial University of Newfoundland. Previous studies have predicted climate change will drive hundreds of bird species to extinction and greatly reduce the ranges of others. But some are shifting the timing of their major life events, such as reproduction and laying eggs, in an attempt to keep up with the changes. The key question, Mayor said, is whether this strategy will work long term. "If anything could adapt to climate change, you'd think that birds that migrate thousands of miles could," he said. "It's much easier for them to move in response to climate conditions than salamanders, for example, or trees. But because every species relates to another, one of our fears is that climate change can disrupt these relationships between organisms such that their critical life events are not timed optimally, putting them at risk." Birds leave their winter homes in Central and South America for the north based on the seasonal shift in hours of daylight, a cue unaltered by climate change. To produce healthy young, they must arrive at their breeding grounds to take advantage of the early-season boom in insects that emerge with springtime plant growth. But as climate change shifts the timing of when plants put out new leaves -- a temperature-driven process known as green-up - migrating birds become more likely to reach breeding grounds when temperatures are still frigid and food is scarce or after insect numbers have begun to dwindle. The researchers found green-up is beginning earlier in eastern North America and -- surprisingly -- later in the West. Birds that breed primarily in eastern temperate forests tended to lag behind green-up while species that breed in western forests reached breeding grounds too early. The rate of change is concerning, given predicted accelerating climatic changes, which could mean timing will be more out of sync in the future, said study co-author Rob Guralnick, associate curator of bioinformatics at the Florida Museum. "That's the future many of us will see," he said. "Not every year will plot exactly along that line, but the trend is clear." The increased variability in weather conditions that comes with climate change could also compound birds' difficulties in tracking year-to-year changes. The team is examining why some species of birds seem to adjust to the shifts better than others, Mayor said. A resource that enabled the study's broad scale investigation of nearly 50 bird species across North America are the tens of thousands of data points contributed by citizen scientists, the researchers said. "As more and more birders record their observations, they are creating a density of data that allows us to start from a continental level and zoom down further and further to the ground," Guralnick said. "It's powerful. Whether they know it or not, birders are helping scientists do their work, and they could end up helping birds in the process." The researchers emphasized the complexity of their findings, which vary by species, region and rate of change. Determining conservation risks and the potential for extinction will require looking at the impacts on each species individually, they said. Diving deeper into the data to determine whether population numbers of bird species that are not adapting to the shift in green-up are falling is one of the next steps in the project. "The natural world is very complex," Mayor said. "When you kick it with a big change by altering the climate, different parts of that natural world respond in different ways. We're just beginning to understand the consequences of this grand unnatural experiment."


News Article | April 17, 2017
Site: www.eurekalert.org

GAINESVILLE, Fla. --- A Florida Museum of Natural History study provides new insights into the complex, shared history between blood-sucking lice and the vitamin-producing bacterial sidekicks that enable them to parasitize mammals, including primates and humans. Lice depend on bacteria to supply essential vitamins missing from blood, their only food source. These bacterial partners live in specialized cells inside their insect hosts and pass from a female louse to her offspring. Lice could not survive without their symbiotic bacteria, and the bacteria, in turn, cannot live outside their insect hosts. When their partnership began, however, and how it has evolved over time has been unclear. Previous studies suggested lice acquired and replaced their bacterial symbionts multiple times over their evolutionary history. But a study by Florida Museum researchers Bret Boyd and David Reed found that lice that parasitize primates and humans have hosted their endosymbionts continuously for at least 20 to 25 million years, aligning with the time period during which great apes and old world monkeys shared a common ancestor. As primates evolved, so did lice, and the evolution of their bacterial partners stayed closely in step. The data provide a new perspective on the evolutionary tree of these symbiotic bacteria, said Boyd, who conducted the research as a doctoral student at the museum. "While lice are highly maligned, they provide a wealth of scientific information," said Boyd, now a postdoctoral researcher at the University of Georgia and the study's first author. "Because these symbiotic bacteria are tied to a known evolutionary history between lice and primates, this is an ideal system for studying bacterial genome evolution." Many species of blood-sucking lice only parasitize one species of host, a specificity that can offer glimpses into primate and human evolution, said Reed, curator of mammals and associate director of research and collections at the Florida Museum. "Certain parts of our history are murky and hard to reconstruct," he said. "The evolution of lice and their symbiotic bacteria helps shed light on human and primate evolutionary history, providing new clues to our past." To gain a more complete picture of how lice and their bacterial symbionts have coevolved, the researchers sequenced and assembled genomes of endosymbionts from human, chimpanzee, gorilla and red colobus monkey lice. They found that the bacteria's genomes are tiny, hovering between 530,000 and 570,000 base pairs -- E. coli's genome, by comparison, is about 4.6 million base pairs. Small genomes are a typical feature of insect symbionts, which lose much of their genome over the course of their relationships with their hosts. Comparing different symbiont genomes, the researchers discovered evidence of extensive genome remodeling during the last 25 million years that has resulted in genes critical to louse-symbiont symbiosis being close to one another in the bacterial genome. This arrangement likely proved advantageous, as it persists in many louse symbionts today, Boyd said. The study also showed that much of the symbiont genome is devoted to vitamin synthesis. In lice that parasitize humans, gorillas, chimpanzees and monkeys, symbionts make B-vitamins crucial for basic cellular processes How symbiont genomes shrank over time and which genes remain are key research questions in basic and applied sciences, Boyd said. "The process by which symbiont genomes change is important to understanding how insects and bacteria form mutualistic relationships that can persist for tens to hundreds of millions of years," he said. "The genes that are retained in the tiny genome provide insights into which genes are essential to maintain bacterial life."


News Article | April 17, 2017
Site: www.chromatographytechniques.com

A Florida Museum of Natural History study provides new insights into the complex, shared history between blood-sucking lice and the vitamin-producing bacterial sidekicks that enable them to parasitize mammals, including primates and humans. Lice depend on bacteria to supply essential vitamins missing from blood, their only food source. These bacterial partners live in specialized cells inside their insect hosts and pass from a female louse to her offspring. Lice could not survive without their symbiotic bacteria, and the bacteria, in turn, cannot live outside their insect hosts. When their partnership began, however, and how it has evolved over time has been unclear. Previous studies suggested lice acquired and replaced their bacterial symbionts multiple times over their evolutionary history. But a study by Florida Museum researchers Bret Boyd and David Reed found that lice that parasitize primates and humans have hosted their endosymbionts continuously for at least 20 to 25 million years, aligning with the time period during which great apes and old world monkeys shared a common ancestor. As primates evolved, so did lice, and the evolution of their bacterial partners stayed closely in step. The data provide a new perspective on the evolutionary tree of these symbiotic bacteria, said Boyd, who conducted the research as a doctoral student at the museum. "While lice are highly maligned, they provide a wealth of scientific information," said Boyd, now a postdoctoral researcher at the University of Georgia and the study's first author. "Because these symbiotic bacteria are tied to a known evolutionary history between lice and primates, this is an ideal system for studying bacterial genome evolution." Many species of blood-sucking lice only parasitize one species of host, a specificity that can offer glimpses into primate and human evolution, said Reed, curator of mammals and associate director of research and collections at the Florida Museum. "Certain parts of our history are murky and hard to reconstruct," he said. "The evolution of lice and their symbiotic bacteria helps shed light on human and primate evolutionary history, providing new clues to our past." To gain a more complete picture of how lice and their bacterial symbionts have coevolved, the researchers sequenced and assembled genomes of endosymbionts from human, chimpanzee, gorilla and red colobus monkey lice. They found that the bacteria's genomes are tiny, hovering between 530,000 and 570,000 base pairs -- E. coli's genome, by comparison, is about 4.6 million base pairs. Small genomes are a typical feature of insect symbionts, which lose much of their genome over the course of their relationships with their hosts. Comparing different symbiont genomes, the researchers discovered evidence of extensive genome remodeling during the last 25 million years that has resulted in genes critical to louse-symbiont symbiosis being close to one another in the bacterial genome. This arrangement likely proved advantageous, as it persists in many louse symbionts today, Boyd said. The study also showed that much of the symbiont genome is devoted to vitamin synthesis. In lice that parasitize humans, gorillas, chimpanzees and monkeys, symbionts make B-vitamins crucial for basic cellular processes How symbiont genomes shrank over time and which genes remain are key research questions in basic and applied sciences, Boyd said. "The process by which symbiont genomes change is important to understanding how insects and bacteria form mutualistic relationships that can persist for tens to hundreds of millions of years," he said. "The genes that are retained in the tiny genome provide insights into which genes are essential to maintain bacterial life."


News Article | March 15, 2017
Site: www.techtimes.com

Around 54 million years ago, when Earth suddenly got really hot, an ancient horse was about the size of a dog. Then it dwarfed, going down to the size of a cat. This is no longer a distant possibility, as global warming continues on its course and affects various life forms on the planet, new research concludes. University of New Hampshire researcher Abigail D’Ambrosia, who led the study, warned that mammals could shrink in the future under even more accelerated man-made warming. “It’s something we need to keep an eye out for. The question is how fast are we going to see these changes,” D’Ambrosia said in a statement. The results are based on an analysis of fossilized teeth and jaw fragments obtained from northwestern Wyoming’s Bighorn Basin, located around 80 miles east of Yellowstone National Park. Measuring teeth is a good way to determine body size of adult mammals from bygone eras, D’Ambrosia explained. She discovered mammal dwarfing during the largest ancient warming event that took place about 56 million years ago, which saw a temperature rise of 9 degrees Fahrenheit or more. Warm-blooded creatures shrank when carbon dioxide levels climbed and temperatures spiked to unprecedented levels. The earliest squid, Sifrhippus, shrank by 30 percent at a minimum in the first 130,000 years of the warming event, but as the temperature gradually returned to normal levels, its body size was able to rebound by 76 percent. An early compact horse called Arenahippus pernix became 14 percent smaller, moving from 17 pounds to just 14.6 pounds. From being approximately dog-like in built, it shrank to the size of a cat. The lemur-like primate Cantius abditus, on the other hand, shriveled around 4 percent — despite studies showing that the species typically got bigger over time. The findings suggested that shrinking response to heightened climate change proportionately scales with the magnitude of the warming. The small horse decreased by about 30 percent in the first warming event, while a different small horse shrank by 14 percent in the second event, which was approximately half as intense. Scientists believe that body size plays a role in climate adaptation. Since they have more skin or fur per pound than their bigger counterparts, smaller animals can let more heat escape, thus they are better adapted for warmer environments. Larger animals, meanwhile, fare better in the cold since they have less skin per pound and better retain heat. The finding that mammals shrink in warmer climates is no longer strange or surprising. As an example of the so-called Bergmann’s Rule, red foxes living in higher and cooler latitudes are larger in size compared to those residing closer to the equator. Other reasons, however, may play a part in dwarfing. These could include the inability to get enough food or water. Jonathan Bloch, Florida Museum of Natural History’s curator of vertebrate paleontology, said the results prove significant. “If we start to see patterns repeat themselves, we can learn from that,” said Bloch, who wasn’t part of the research. The findings were discussed in the journal Science Advances. A separate study warned that climate change impact on birds and mammals are largely underreported. A team from University of Queensland in Australia found that nearly 700 birds and mammals have already responded to the changes in a negative way. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.


News Article | May 15, 2017
Site: www.eurekalert.org

GAINESVILLE, Fla. --- New research shows climate change is altering the delicate seasonal clock that North American migratory songbirds rely on to successfully mate and raise healthy offspring, setting in motion a domino effect that could threaten the survival of many familiar backyard bird species. A growing shift in the onset of spring has left nine of 48 species of songbirds studied unable to reach their northern breeding grounds at the calendar marks critical for producing the next generation of fledglings, according to a paper published today in Scientific Reports. That's because in many regions, warming temperatures are triggering plants to begin their growth earlier or later than normal, skewing biological cycles that have long been in sync. The result, researchers say, could be a future much like the one Rachel Carson hinted at more than 50 years ago. "It's like 'Silent Spring,' but with a more elusive culprit," said Stephen Mayor, a postdoctoral researcher with the Florida Museum of Natural History at the University of Florida and first author of the study. "We're seeing spring-like conditions well before birds arrive. The growing mismatch means fewer birds are likely to survive, reproduce and return the following year. These are birds people are used to seeing and hearing in their backyards. They're part of the American landscape, part of our psyche. To imagine a future where they're much less common would be a real loss." A multi-institutional team led by Mayor used data from satellites and citizen scientists to study how quickly the interval between spring plant growth and the arrival of 48 songbird species across North America changed from 2001 to 2012. The researchers found the gap lengthened by over half a day per year across all species on average, a rate of five days per decade--but for some species, the mismatch is growing at double or triple that rate. Nine species were clearly unable to keep up with the shift: great crested flycatchers, indigo buntings, scarlet tanagers, rose-breasted grosbeaks, eastern wood-pewees, yellow-billed cuckoos, northern parulas, blue-winged warblers and Townsend's warblers. While the majority of species studied adjusted their arrival dates, the study suggests the rate of change could be outpacing their efforts. The study is the first to investigate the increasing mismatch between songbirds' springtime arrival and plant growth at the continental scale and across dozens of species, said Mayor, who led the project chiefly at Memorial University of Newfoundland. Previous studies have predicted climate change will drive hundreds of bird species to extinction and greatly reduce the ranges of others. But some are shifting the timing of their major life events, such as reproduction and laying eggs, in an attempt to keep up with the changes. The key question, Mayor said, is whether this strategy will work long term. "If anything could adapt to climate change, you'd think that birds that migrate thousands of miles could," he said. "It's much easier for them to move in response to climate conditions than salamanders, for example, or trees. But because every species relates to another, one of our fears is that climate change can disrupt these relationships between organisms such that their critical life events are not timed optimally, putting them at risk." Birds leave their winter homes in Central and South America for the north based on the seasonal shift in hours of daylight, a cue unaltered by climate change. To produce healthy young, they must arrive at their breeding grounds to take advantage of the early-season boom in insects that emerge with springtime plant growth. But as climate change shifts the timing of when plants put out new leaves -- a temperature-driven process known as green-up - migrating birds become more likely to reach breeding grounds when temperatures are still frigid and food is scarce or after insect numbers have begun to dwindle. The researchers found green-up is beginning earlier in eastern North America and -- surprisingly -- later in the West. Birds that breed primarily in eastern temperate forests tended to lag behind green-up while species that breed in western forests reached breeding grounds too early. The rate of change is concerning, given predicted accelerating climatic changes, which could mean timing will be more out of sync in the future, said study co-author Rob Guralnick, associate curator of bioinformatics at the Florida Museum. "That's the future many of us will see," he said. "Not every year will plot exactly along that line, but the trend is clear." The increased variability in weather conditions that comes with climate change could also compound birds' difficulties in tracking year-to-year changes. The team is examining why some species of birds seem to adjust to the shifts better than others, Mayor said. A resource that enabled the study's broad scale investigation of nearly 50 bird species across North America are the tens of thousands of data points contributed by citizen scientists, the researchers said. "As more and more birders record their observations, they are creating a density of data that allows us to start from a continental level and zoom down further and further to the ground," Guralnick said. "It's powerful. Whether they know it or not, birders are helping scientists do their work, and they could end up helping birds in the process." The researchers emphasized the complexity of their findings, which vary by species, region and rate of change. Determining conservation risks and the potential for extinction will require looking at the impacts on each species individually, they said. Diving deeper into the data to determine whether population numbers of bird species that are not adapting to the shift in green-up are falling is one of the next steps in the project. "The natural world is very complex," Mayor said. "When you kick it with a big change by altering the climate, different parts of that natural world respond in different ways. We're just beginning to understand the consequences of this grand unnatural experiment." Researchers from Memorial University of Newfoundland, the University of Colorado, the University of Connecticut, Florida International University, Murdoch University and the Illinois Natural History Survey also contributed to the study.


News Article | May 9, 2017
Site: www.eurekalert.org

GAINESVILLE, Fla. --- The relentless roar of natural gas compressors influences the numbers of insects and spiders nearby, triggering decreases in many types of arthropods sensitive to sounds and vibrations, a collaborative Florida Museum of Natural History study shows. Populations of grasshoppers, froghoppers, velvet ants, wolf spiders and cave, camel and spider crickets dropped significantly in areas near gas compressors, while leafhopper numbers rose. These shifts in arthropod communities could set off a cascade of larger-scale ecological consequences, as insects and spiders play fundamental roles in food webs, pollination, decomposition and overall ecological health, said study co-author Akito Kawahara, assistant professor and curator at the museum's McGuire Center for Lepidoptera and Biodiversity at the University of Florida. "Noise pollution affects all kinds of animals, and insects are no exception," Kawahara said. "They might be small, but they're the dominant animals on the planet in terms of numbers. What happens to them affects whole ecosystems." The study joins a growing body of research on how artificial noise alters animal behavior and disrupts ecosystems and is the first to examine noise pollution's effects on arthropod distribution and community diversity. Gas compressors, which can range from minivan- to warehouse-sized, extract and move natural gas along a pipeline, emitting intense, low-frequency noise. Previous studies have shown noise pollution from compressors changes the activity levels and distribution of bats and birds, key predators of insects and spiders. Kawahara joined a multi-institutional research group, led by the study's first author Jessie Bunkley and principal investigator Jesse Barber of Boise State University, to test how the landscape-scale noise produced by gas compressors affects arthropod communities, many of which rely on sound and vibrations to find food, meet a mate, communicate and detect predators. The research team used pitfall traps to take a census of spider and non-flying insect populations at San Juan Basin, New Mexico, the second largest natural gas field in the U.S. The team tested five sites with compressors and five ecologically-similar sites without compressors and compared the relative abundance of specimens. Compressor sites had 95 percent fewer cave, camel and spider crickets, 52 percent fewer froghoppers and 24 percent fewer grasshoppers than sites without compressors. For every 10-decibel increase in noise, velvet ant populations dropped 56 percent and wolf spiders decreased by 44 percent. Unexpectedly, leafhopper numbers surged in response to noise, increasing 44 percent for each additional 10 decibels of sound. Some arthropods, such as jumping spiders, ground spiders, ants and leaf beetles, showed no significant differences in their numbers between sites. All arthropod groups that responded to louder background sound levels or compressor noise make or sense sounds or vibrations, suggesting compressor noise could directly interfere with or mask important information they receive or exchange. Compressor noise could negatively affect wolf spiders, for example, because they are hunters that depend on vibrations to detect prey. Conversely, noise could act as a "predator shield" for leafhoppers, hiding their sounds and movements from their natural enemies. But parsing out why a particular group of arthropods increased or decreased in response to compressor noise is difficult, Kawahara said. While the number of crickets in the Rhaphidophoridae family plunged in response to compressor noise, crickets in the Gryllidae family did not seem to be affected. "The range of changes in arthropod abundance sheds light on the fact that we're dealing with a very complicated network of animal interactions," Kawahara said. He pointed to the value of museum collections as archives of past biodiversity that can record changes to the environment over time. "We are rapidly changing our environment in terms of sound, light, air and climate," he said. "Unless we have historical documentation of what was in an area at a particular time, it's hard to detect these changes at a fine scale. Museum specimens document biodiversity over hundreds of years, offering those snapshots of time."

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