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News Article | May 23, 2017
Site: phys.org

Brown-headed cowbirds are known to lay their eggs in the nests of more than 200 other bird species of varying sizes, and typically do so after the host bird has laid her own eggs. The new study, led by a team at the University of Illinois, found that when cowbird mothers chose the nest of a larger host bird, they preferred those that held smaller-than-average eggs for that species. Smaller host eggs give the cowbird eggs a better chance of being successfully incubated; smaller host hatchlings mean the cowbird chicks face less competition for food and nest space. "It implies a level of resolution in cowbird decision-making that people hadn't seen before," said Loren Merrill, a postdoctoral researcher at the Illinois Natural History Survey who conducted the study with INHS scientists Scott Chiavacci and Thomas Benson and Illinois State University researcher Ryan Paitz. "Scientists originally saw cowbirds as egg dumpers that would put their eggs in any nest they found," Merrill said. "And while that may be the case in some areas, or for some birds, it doesn't tell the whole story. In fact, the more people have looked at cowbird behavior, the more our understanding has evolved of exactly how discriminating cowbirds can be." The findings are reported in the journal Oecologia. From April through August for five seasons ending in 2015, the researchers hunted through 16 shrubland sites across Illinois, looking for cowbirds and nests in which cowbirds might place their eggs. "Nest searching is really fun fieldwork, except when you're trekking through poison ivy- and hawthorn-infested lands," Merrill said. "You either get really lucky and see nesting material in a bird's mouth, and you watch until they lead you to a nest, or you listen and watch for the vocalizations and behaviors the adults use when you are close to a nest." Cowbirds use similar tactics to scout for host nests. "They do a lot of skulking around the underbrush," Merrill said. "They'll also perch in an inconspicuous place and just watch. They are cuing in on the behavior of hosts that are building their nests or taking food back to nests." The research team found nearly 3,000 nests of 34 bird species and checked each nest roughly every three days. Cowbirds placed eggs in more than 400 of these nests. In addition to weighing and measuring cowbird and host eggs in more than 180 nests, the researchers also tested the composition of some cowbird eggs to determine whether female cowbirds give some eggs an added boost, such as a greater proportion of yolk or higher levels of yolk hormones like testosterone. "The cowbird could adjust allocation to the egg based on the perceived value of that egg. If she thinks the egg is in a good environment, she can invest more," Merrill said. "Or, if the host isn't appropriate and she doesn't think the environment is favorable, she could invest less." The researchers found no variation in egg investment based on the differences among host species or size variations within a host species, however. "We didn't see evidence that female cowbirds were adjusting resources in that respect, but that's not to say it isn't happening," Merrill said. Tracking individual female cowbirds would help scientists better understand how mother cowbirds try to help their offspring. "It's really hard to do," he said. "But being able to track the individual females over time and identify where they are depositing eggs would provide a lot of insight into how much of what we see is an adaptive allocation strategy, or whether the mother's health and other constraints are driving her behavior." More information: Loren Merrill et al, Rates of parasitism, but not allocation of egg resources, vary among and within hosts of a generalist avian brood parasite, Oecologia (2017). DOI: 10.1007/s00442-017-3870-z


News Article | May 25, 2017
Site: www.sciencedaily.com

Brown-headed cowbirds are unconventional mothers. Rather than building nests and nurturing their chicks, they lay their eggs in the nests of other species, leaving their young ones to compete for resources with the foster parents' own hatchlings. Despite their reputation as uncaring, absentee moms, cowbird mothers are capable of making sophisticated choices among potential nests in order to give their offspring a better chance of thriving, a new study shows. Brown-headed cowbirds are known to lay their eggs in the nests of more than 200 other bird species of varying sizes, and typically do so after the host bird has laid her own eggs. The new study, led by a team at the University of Illinois, found that when cowbird mothers chose the nest of a larger host bird, they preferred those that held smaller-than-average eggs for that species. Smaller host eggs give the cowbird eggs a better chance of being successfully incubated; smaller host hatchlings mean the cowbird chicks face less competition for food and nest space. "It implies a level of resolution in cowbird decision-making that people hadn't seen before," said Loren Merrill, a postdoctoral researcher at the Illinois Natural History Survey who conducted the study with INHS scientists Scott Chiavacci and Thomas Benson and Illinois State University researcher Ryan Paitz. "Scientists originally saw cowbirds as egg dumpers that would put their eggs in any nest they found," Merrill said. "And while that may be the case in some areas, or for some birds, it doesn't tell the whole story. In fact, the more people have looked at cowbird behavior, the more our understanding has evolved of exactly how discriminating cowbirds can be." The findings are reported in the journal Oecologia. From April through August for five seasons ending in 2015, the researchers hunted through 16 shrubland sites across Illinois, looking for cowbirds and nests in which cowbirds might place their eggs. "Nest searching is really fun fieldwork, except when you're trekking through poison ivy- and hawthorn-infested lands," Merrill said. "You either get really lucky and see nesting material in a bird's mouth, and you watch until they lead you to a nest, or you listen and watch for the vocalizations and behaviors the adults use when you are close to a nest." Cowbirds use similar tactics to scout for host nests. "They do a lot of skulking around the underbrush," Merrill said. "They'll also perch in an inconspicuous place and just watch. They are cuing in on the behavior of hosts that are building their nests or taking food back to nests." The research team found nearly 3,000 nests of 34 bird species and checked each nest roughly every three days. Cowbirds placed eggs in more than 400 of these nests. In addition to weighing and measuring cowbird and host eggs in more than 180 nests, the researchers also tested the composition of some cowbird eggs to determine whether female cowbirds give some eggs an added boost, such as a greater proportion of yolk or higher levels of yolk hormones like testosterone. "The cowbird could adjust allocation to the egg based on the perceived value of that egg. If she thinks the egg is in a good environment, she can invest more," Merrill said. "Or, if the host isn't appropriate and she doesn't think the environment is favorable, she could invest less." The researchers found no variation in egg investment based on the differences among host species or size variations within a host species, however. "We didn't see evidence that female cowbirds were adjusting resources in that respect, but that's not to say it isn't happening," Merrill said. Tracking individual female cowbirds would help scientists better understand how mother cowbirds try to help their offspring. "It's really hard to do," he said. "But being able to track the individual females over time and identify where they are depositing eggs would provide a lot of insight into how much of what we see is an adaptive allocation strategy, or whether the mother's health and other constraints are driving her behavior."


News Article | May 23, 2017
Site: www.eurekalert.org

CHAMPAIGN, Ill. -- Brown-headed cowbirds are unconventional mothers. Rather than building nests and nurturing their chicks, they lay their eggs in the nests of other species, leaving their young ones to compete for resources with the foster parents' own hatchlings. Despite their reputation as uncaring, absentee moms, cowbird mothers are capable of making sophisticated choices among potential nests in order to give their offspring a better chance of thriving, a new study shows. Brown-headed cowbirds are known to lay their eggs in the nests of more than 200 other bird species of varying sizes, and typically do so after the host bird has laid her own eggs. The new study, led by a team at the University of Illinois, found that when cowbird mothers chose the nest of a larger host bird, they preferred those that held smaller-than-average eggs for that species. Smaller host eggs give the cowbird eggs a better chance of being successfully incubated; smaller host hatchlings mean the cowbird chicks face less competition for food and nest space. "It implies a level of resolution in cowbird decision-making that people hadn't seen before," said Loren Merrill, a postdoctoral researcher at the Illinois Natural History Survey who conducted the study with INHS scientists Scott Chiavacci and Thomas Benson and Illinois State University researcher Ryan Paitz. "Scientists originally saw cowbirds as egg dumpers that would put their eggs in any nest they found," Merrill said. "And while that may be the case in some areas, or for some birds, it doesn't tell the whole story. In fact, the more people have looked at cowbird behavior, the more our understanding has evolved of exactly how discriminating cowbirds can be." The findings are reported in the journal Oecologia. From April through August for five seasons ending in 2015, the researchers hunted through 16 shrubland sites across Illinois, looking for cowbirds and nests in which cowbirds might place their eggs. "Nest searching is really fun fieldwork, except when you're trekking through poison ivy- and hawthorn-infested lands," Merrill said. "You either get really lucky and see nesting material in a bird's mouth, and you watch until they lead you to a nest, or you listen and watch for the vocalizations and behaviors the adults use when you are close to a nest." Cowbirds use similar tactics to scout for host nests. "They do a lot of skulking around the underbrush," Merrill said. "They'll also perch in an inconspicuous place and just watch. They are cuing in on the behavior of hosts that are building their nests or taking food back to nests." The research team found nearly 3,000 nests of 34 bird species and checked each nest roughly every three days. Cowbirds placed eggs in more than 400 of these nests. In addition to weighing and measuring cowbird and host eggs in more than 180 nests, the researchers also tested the composition of some cowbird eggs to determine whether female cowbirds give some eggs an added boost, such as a greater proportion of yolk or higher levels of yolk hormones like testosterone. "The cowbird could adjust allocation to the egg based on the perceived value of that egg. If she thinks the egg is in a good environment, she can invest more," Merrill said. "Or, if the host isn't appropriate and she doesn't think the environment is favorable, she could invest less." The researchers found no variation in egg investment based on the differences among host species or size variations within a host species, however. "We didn't see evidence that female cowbirds were adjusting resources in that respect, but that's not to say it isn't happening," Merrill said. Tracking individual female cowbirds would help scientists better understand how mother cowbirds try to help their offspring. "It's really hard to do," he said. "But being able to track the individual females over time and identify where they are depositing eggs would provide a lot of insight into how much of what we see is an adaptive allocation strategy, or whether the mother's health and other constraints are driving her behavior." The INHS is a division of the Prairie Research Institute at the U. of I. The paper "Rates of parasitism, but not allocation of egg resources, vary among and within hosts of a generalist avian brood parasite" is available online and from the U. of I. News Bureau.


News Article | May 1, 2017
Site: www.rdmag.com

They found it in the Illinois River near the city of Marseilles, Illinois, about 80 miles west of Lake Michigan - a strange entry point for an invasive Asian clam. The scientists who found it have no idea how it got there. But the discovery - along with genetic tests that confirm its uniqueness - means that a new species or "form" of invasive clam has made its official debut in North America. The researchers report the find in the journal BioInvasions Records. This is only the latest invasive aquatic species to settle in North America, said Illinois Natural History Survey aquatic ecologist Jeremy Tiemann, who discovered the new clam with INHS mussel field biologist Sarah Douglass in late 2015. The INHS is a division of the Prairie Research Institute at the University of Illinois. "In the Midwest, you have invasive bivalves, including zebra mussels, and several species of invasive fish: Asian carp, black carp and even goldfish," Tiemann said. There are exotic plants, like Eurasian milfoil. There is an invasive water flea from Africa, Asia and Australia. There also are several kinds of invasive snails, the researchers said. All of these create problems for the natives. The new invader is a member of the genus Corbicula, which was first observed in Vancouver, British Columbia, in 1924. It likely was brought to North America by immigrants from Asia who used the clams as food, the researchers said. Within a few decades, it had colonized many of the major waterways of North America. (See animated map). Douglass and Tiemann found the new clams while hunting through a mudflat for a federally endangered native clam, the scaleshell, that had been spotted in the same location two years before. They noticed that this tiny creature, roughly the size of a fingernail, had unusual physical characteristics compared with the other invasive species of Corbicula found in this region. The Illinois team shared the find with researchers at the University of Michigan, who conducted genetic tests that confirmed the new clams were distinct from earlier Corbiculainvaders. Despite the genetic and physical differences, the researchers can't say whether the clam is a new species. Corbicula have reproductive strategies that make them difficult to classify, the researchers said. To begin with, they are androgenic clones. "When the sperm fertilizes the egg, it kicks out the maternal nuclear DNA, retaining only the male's, and thus producing clones of the father," Tiemann said. "These offspring, however, retain the mother's mitochondrial DNA, which resides in tiny organelles outside the nucleus." Corbicula also can hybridize with other Corbicula taxa, further complicating the task of classifying them, Tiemann said. "To compound matters even more, Corbicula can also be hermaphrodites, so they can fertilize themselves," he said. "This means that it takes only a single clam to spawn a new population." To help distinguish among species, researchers can examine the nuclear or mitochondrial DNA, Tiemann said. "With Corbicula, the nuclear DNA tells one story, but the mitochondrial DNA can suggest something different," he said. "As a result, we use the word 'form' to distinguish different taxa within a group, as is the case with Corbicula." No matter how it is classified, the new invader is likely not good news for native clams or the river ecosystem as a whole, the researchers said. "Corbicula consume the same resources as the natives," Tiemann said. "It's thought that they also can consume the larvae of the natives, although that hasn't been proved," Douglass said. Invaders often have no natural enemies in a new locale, and tend to overpopulate, driving out the natives and sometimes overextending themselves, she said. So far, the ultimate consequences of the latest exotic to take up residence in U.S. waters remains to be seen, the researchers said. "But if past invasions are any indication, it may signal further erosion of ecosystem services traditionally provided by watersheds already impacted by Corbicula," Tiemann said.


The western corn rootworm was first classified as a corn pest in 1867. Its green relative, the northern corn rootworm, was classified as a corn pest in Illinois and Missouri by the late 1870s Credit: Joseph Spencer, Illinois Natural History Survey. According to estimates, the current global population is more than 7.4 billion people and is growing at a rate of 88 million people per year. Developing corn varieties that are resistant to pests is vital to sustain the estimated 9 billion global population by 2050. Now, researchers at the University of Missouri, using advanced nuclear methods, have determined the mechanisms corn plants use to combat the western corn rootworm, a major pest threatening the growth of the vital food source. Scientists believe that using the knowledge gained from these cutting-edge studies could help crop breeders in developing new resistant lines of corn and make significant strides toward solving global food shortages. "The western corn rootworm is a voracious pest," said Richard Ferrieri, a research professor in the MU Interdisciplinary Plant Group, and an investigator at the MU Research Reactor (MURR). "Rootworm larvae hatch in the soil during late spring and immediately begin feeding on the crop's root system. Mild damage to the root system can hinder water and nutrient uptake, threatening plant fitness, while more severe damage can result in the plant falling over." Breeding corn that can fight these pests is a promising alternative. Ferrieri, and his international team of researchers, including scientists from the University of Bern in Switzerland, Brookhaven National Laboratory in New York and the U.S. Department of Agriculture, used radioisotopes to trace essential nutrients and hormones as they moved through live corn plants. In a series of tests, the team injected radioisotope tracers in healthy and rootworm-infested corn plants. "For some time, we've known that auxin, a powerful plant hormone, is involved in stimulating new root growth," Ferrieri said. "Our target was to follow auxin's biosynthesis and movement in both healthy and stressed plants and determine how it contributes to this process." By tagging auxin with a radioactive tracer, the researchers were able to use a medical diagnostic imaging tool call positron emission tomography, or PET imaging, to "watch" the movement of auxin in living plant roots in real time. Similarly, they attached a radioactive tracer to an amino acid called glutamine that is important in controlling auxin chemistry, and observed the pathways the corn plants used to transport glutamine and how it influenced auxin biosynthesis. The researchers found that auxin is tightly regulated at the root tissue level where rootworms are feeding. The study also revealed that auxin biosynthesis is vital to root regrowth and involves highly specific biochemical pathways that are influenced by the rootworm and triggered by glutamine metabolism. "This work has revealed several new insights about root regrowth in crops that can fend off a rootworm attack," Ferrieri said. "Our observations suggest that improving glutamine utilization could be a good place to start for crop breeding programs or for engineering rootworm-resistant corn for a growing global population." Ferrieri's work highlights the capabilities of the MURR, a crucial component to research at the university for more than 40 years. Operating 6.5 days a week, 52 weeks a year, scientists from across the campus use the 10-megawatt facility to not only provide crucial radioisotopes for clinical settings globally, but also to carbon date artifacts, improve medical diagnostic tools and prevent illness. MURR also is home to a PETrace cyclotron that is used to produced other radioisotopes for medical diagnostic imaging. The study, "Dynamic Precision Phenotyping Reveals Mechanism of Crop Tolerance to Root Herbivory," was published in Plant Physiology. Explore further: Benefits of Bt corn go beyond rootworm resistance More information: Dynamic Precision Phenotyping Reveals Mechanism of Crop Tolerance to Root Herbivory, dx.doi.org/10.1104/pp.16.00735


News Article | February 27, 2017
Site: www.eurekalert.org

CHAMPAIGN, Ill. -- An iconic bird whose booming mating calls once reverberated across "the Prairie State" can survive in Illinois with the help of periodic human interventions, researchers report. The greater prairie chicken once dominated the American Midwest, but today the bird is in trouble in many parts of its historic range. It is no longer found in Arkansas, Indiana, Kentucky, Michigan, Ohio, Tennessee, Texas or Wyoming, states where it once flourished. And in Illinois, an estimated 186 birds remain in two adjoining counties in the southern part of the state. "They used to be all over the state," said Illinois Natural History Survey conservation biologist Mark Davis, who participated in a genetic analysis of the Illinois birds. "This was the tallgrass prairie state. You couldn't throw a rock into a field without hitting a prairie chicken." The reason for the decline is simple, Davis said. "We changed our land-use practices from having a lot of prairie, then to wheat, hay and alfalfa, and now to vast expanses of corn and soybeans," he said. "Prairie chickens used to have 20 million acres of prairie in Illinois. Now, they have around 2,000. At the same time, population size went from 10 to 14 million in the 1860s to the 100 to 200 or so we have today. There just isn't enough habitat." Environmental officials have made two efforts to rescue Illinois' dwindling prairie chicken populations, which are suffering from a lack of habitat and declining genetic diversity. Between 1992 and 1998, teams imported more than 200 prairie chickens from other states. "In Illinois, the first translocation brought in birds from all over the upper Midwest - from North Dakota, Minnesota, Kansas and Nebraska," Davis said. "And for a short period of time, it seemed to work." More chicks survived to reproductive age and genetic diversity spiked, he said. To understand how well the birds were doing long after that first translocation, Davis and his colleagues analyzed the DNA from feathers collected in the birds' courtship grounds from 2010-13. The researchers report their findings in the journal Royal Society Open Science. "What our paper reveals is that about 20 years after the translocation of new prairie chickens into Illinois, we see another decrease in genetic diversity and a decline in the number of birds," Davis said. The study confirmed that the only two remaining populations of prairie chickens in Illinois -- one in Marion County and the other in Jasper County -- are genetically isolated from one another, Davis said. The birds have access to a few hundred acres of territory overall, but the land is subdivided by roads and power lines, which represent additional barriers. "They're also surrounded by an agricultural desert of corn and soybeans," Davis said. The study identified 88 unique males using the courtship grounds, where the birds strut and boom to attract females. The team estimates that roughly the same number of females live in Illinois. The researchers' conclusion: A lack of habitat endangers prairie chickens' long-term survival in Illinois. Without periodic human intervention - in the form of translocations of birds from other states - the population could die out. "This is the issue that sage grouse are facing out West," Davis said. "This is the issue that lesser prairie chickens are facing in Texas and Oklahoma. These are big birds that need a big landscape that we don't have anymore." There are still strongholds for prairie chickens in Kansas, Minnesota, Nebraska and South Dakota, Davis said. In western Minnesota, for example, a tradition of protection for game animals and a hefty excise tax on hunting and fishing licenses has allowed the state to purchase lands and protect a patchwork of interconnected grassland habitat, he said. "Now you have this swath of restored prairie and the birds are doing really well -- so much so that a few years ago, on a very limited basis, Minnesota was able to have the first prairie chickens taken by hunting in many years," he said. But Illinois has strong agricultural traditions, and Davis doesn't foresee a similar effort in the state. "Providing food for the world does come at a cost, and that cost is habitat for wildlife," he said. "To sustain prairie chickens in Illinois, we have two options," Davis said. "We can purchase and restore as much prairie habitat as possible. In lieu of that, we need to support the periodic translocations of new birds to Illinois to preserve this prairie icon." The INHS is a division of the Prairie Research Institute at the U. of I. To reach Mark Davis, call 217-333-6294; email davis63@illinois.edu. The paper "Genetic rescue, the greater prairie chicken, and the problem of conservation-reliance in the Anthropocene" is available online and from the U. of I. News Bureau.DOI: 10.1098/rsos.160736


News Article | January 28, 2016
Site: www.biosciencetechnology.com

Using head shape and genetic analyses, new research challenges the formerly designated subspecies within the western rattlesnake species. These findings have important implications for ecological conservation efforts across the United States and could provide the basis for new species designations. The results are published in the journal PLOS ONE. The western rattlesnake (Crotalus viridis) is found across a significant portion of the United States, from Mexico to Canada and from the Missouri River to the West Coast. Most work classifying rattlesnake species and subspecies was conducted in the mid-20th century. Since then, scientific methods have advanced to allow for a more comprehensive understanding of the path of rattlesnake evolution. Mark Davis, a research scientist at the Illinois Natural History Survey, part of the Prairie Research Institute at the University of Illinois, collected data from nearly 3,000 western rattlesnakes for this study. He gathered data from preserved samples of this group available at natural history museums across the western United States. “We are able to see that these different subspecies, which have different habits, live in different areas and have other different characteristics, have heads that have been shaped differently over evolutionary time,” Davis said. For western rattlesnakes, the head is the primary organ for conducting daily life. It is especially important for feeding and reproductive rituals. Head shape has evolved to better accommodate these critical behaviors, Davis said. The shape can vary drastically between different species of snakes. Given the importance of this feature, Davis and his colleagues used geometric morphometrics, a relatively novel method that allows researchers to quantify head shape without any influence of head size. To complement the shape analyses, Davis and his team analyzed genetic data from the snakes. Combining head shape and genetic information created a comprehensive perspective, Davis said. Together, these data confirm that several groups of snakes previously labeled as subspecies have substantial enough differences to qualify for a separate species designation. One of the greatest challenges to ecological conservation is identifying what species actually exist. For legal protections – including the Endangered Species Act – to be effective, scientists must specifically identify the units of biodiversity that may be in need of protection. ”It’s important to me to try to work with conservation practitioners to develop strategies for preserving biodiversity,” Davis said. With this study, Davis and his colleagues recommend officially elevating to the level of full species several groups of snakes previously believed to be subspecies. Davis expects that the national and international organizations responsible for naming various species will adopt the recommendations proposed in the study.


News Article | January 27, 2016
Site: phys.org

The results are published in the journal PLOS ONE. The western rattlesnake (Crotalus viridis) is found across a significant portion of the United States, from Mexico to Canada and from the Missouri River to the West Coast. Most work classifying rattlesnake species and subspecies was conducted in the mid-20th century. Since then, scientific methods have advanced to allow for a more comprehensive understanding of the path of rattlesnake evolution. Mark Davis, a research scientist at the Illinois Natural History Survey, part of the Prairie Research Institute at the University of Illinois, collected data from nearly 3,000 western rattlesnakes for this study. He gathered data from preserved samples of this group available at natural history museums across the western United States. "We are able to see that these different subspecies, which have different habits, live in different areas and have other different characteristics, have heads that have been shaped differently over evolutionary time," Davis said. For western rattlesnakes, the head is the primary organ for conducting daily life. It is especially important for feeding and reproductive rituals. Head shape has evolved to better accommodate these critical behaviors, Davis said. The shape can vary drastically between different species of snakes. Given the importance of this feature, Davis and his colleagues used geometric morphometrics, a relatively novel method that allows researchers to quantify head shape without any influence of head size. To complement the shape analyses, Davis and his team analyzed genetic data from the snakes. Combining head shape and genetic information created a comprehensive perspective, Davis said. Together, these data confirm that several groups of snakes previously labeled as subspecies have substantial enough differences to qualify for a separate species designation. One of the greatest challenges to ecological conservation is identifying what species actually exist. For legal protections - including the Endangered Species Act - to be effective, scientists must specifically identify the units of biodiversity that may be in need of protection. "It's important to me to try to work with conservation practitioners to develop strategies for preserving biodiversity," Davis said. With this study, Davis and his colleagues recommend officially elevating to the level of full species several groups of snakes previously believed to be subspecies. Davis expects that the national and international organizations responsible for naming various species will adopt the recommendations proposed in the study. More information: Deconstructing a Species-Complex: Geometric Morphometric and Molecular Analyses Define Species in the Western Rattlesnake (Crotalus viridis), dx.doi.org/10.1371/journal.pone.0146166


Recently, Dr. Brendan O. Morris and Dr. Christopher H. Dietrich, of the University of Illinois at Urbana-Champaign, discovered a new treehopper genus (and its single species) that is found in Texas and northern Mexico, which they describe in an article in the Annals of the Entomological Society of America. They named the new genus Selenacentrus after the singer Selena Quintanilla, who was known as the "Queen of Tejano Music." The new species is called wallacei in honor of Matthew S. Wallace, a biology professor from East Stroudsburg University. The scientists discovered Selenacentrus wallacei after examining 45 specimens of mislabeled treehoppers that were borrowed from collections at the Illinois Natural History Survey, the United States National Museum of Natural History, the American Museum of Natural History, Texas A&M University, and the University of Missouri. Treehoppers are found on all major landmasses except Antarctica and Madagascar. Numbering about 3,500 species in 300 genera, they are divided into three families: Aetalionidae, Melizoderidae, and Membracidae. All treehoppers feed on plant sap by sucking it out with piercing mouthparts. They feed on more than 100 herbaceous and woody plant species. Some treehoppers exude sweet "honeydew" from excess consumed sap, which they share with ants in a mutualistic relationship, the ants swilling honeydew and protecting the treehoppers from predators. Some treehoppers are also known to form mutualistic relationships with wasps and bees. Explore further: 9 new wasp species of the genus Paramblynotus described from Africa and Madagascar More information: B. O. Morris et al. Hidden in Plain Sight: A Remarkable New Genus of Nearctic Treehoppers (Hemiptera: Membracidae), Annals of the Entomological Society of America (2016). DOI: 10.1093/aesa/saw008


The greater prairie chicken once dominated the American Midwest, but today the bird is in trouble in many parts of its historic range. It is no longer found in Arkansas, Indiana, Kentucky, Michigan, Ohio, Tennessee, Texas or Wyoming, states where it once flourished. And in Illinois, an estimated 186 birds remain in two adjoining counties in the southern part of the state. "They used to be all over the state," said Illinois Natural History Survey conservation biologist Mark Davis, who participated in a genetic analysis of the Illinois birds. "This was the tallgrass prairie state. You couldn't throw a rock into a field without hitting a prairie chicken." The reason for the decline is simple, Davis said. "We changed our land-use practices from having a lot of prairie, then to wheat, hay and alfalfa, and now to vast expanses of corn and soybeans," he said. "Prairie chickens used to have 20 million acres of prairie in Illinois. Now, they have around 2,000. At the same time, population size went from 10 to 14 million in the 1860s to the 100 to 200 or so we have today. There just isn't enough habitat." Environmental officials have made two efforts to rescue Illinois' dwindling prairie chicken populations, which are suffering from a lack of habitat and declining genetic diversity. Between 1992 and 1998, teams imported more than 200 prairie chickens from other states. "In Illinois, the first translocation brought in birds from all over the upper Midwest - from North Dakota, Minnesota, Kansas and Nebraska," Davis said. "And for a short period of time, it seemed to work." More chicks survived to reproductive age and genetic diversity spiked, he said. To understand how well the birds were doing long after that first translocation, Davis and his colleagues analyzed the DNA from feathers collected in the birds' courtship grounds from 2010-13. The researchers report their findings in the journal Royal Society Open Science. "What our paper reveals is that about 20 years after the translocation of new prairie chickens into Illinois, we see another decrease in genetic diversity and a decline in the number of birds," Davis said. The study confirmed that the only two remaining populations of prairie chickens in Illinois—one in Marion County and the other in Jasper County—are genetically isolated from one another, Davis said. The birds have access to a few hundred acres of territory overall, but the land is subdivided by roads and power lines, which represent additional barriers. "They're also surrounded by an agricultural desert of corn and soybeans," Davis said. The study identified 88 unique males using the courtship grounds, where the birds strut and boom to attract females. The team estimates that roughly the same number of females live in Illinois. The researchers' conclusion: A lack of habitat endangers prairie chickens' long-term survival in Illinois. Without periodic human intervention - in the form of translocations of birds from other states - the population could die out. "This is the issue that sage grouse are facing out West," Davis said. "This is the issue that lesser prairie chickens are facing in Texas and Oklahoma. These are big birds that need a big landscape that we don't have anymore." There are still strongholds for prairie chickens in Kansas, Minnesota, Nebraska and South Dakota, Davis said. In western Minnesota, for example, a tradition of protection for game animals and a hefty excise tax on hunting and fishing licenses has allowed the state to purchase lands and protect a patchwork of interconnected grassland habitat, he said. "Now you have this swath of restored prairie and the birds are doing really well—so much so that a few years ago, on a very limited basis, Minnesota was able to have the first prairie chickens taken by hunting in many years," he said. But Illinois has strong agricultural traditions, and Davis doesn't foresee a similar effort in the state. "Providing food for the world does come at a cost, and that cost is habitat for wildlife," he said. "To sustain prairie chickens in Illinois, we have two options," Davis said. "We can purchase and restore as much prairie habitat as possible. In lieu of that, we need to support the periodic translocations of new birds to Illinois to preserve this prairie icon." More information: S. M. Mussmann et al, Genetic rescue, the greater prairie chicken and the problem of conservation reliance in the Anthropocene, Royal Society Open Science (2017). DOI: 10.1098/rsos.160736

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