Friday, February 26th, 2016

Mizuki Takahashi – Sullivan, Brian K.; Wooten, Jessica; Schwaner, Terry D.; Sullivan, Keith O.; and Takahashi, Mizuki. “Thirty Years of Hybridization between Toads along the Agua Fria River in Arizona: I. Evidence from Morphology and mtDNA.” Journal of Herpetology 49, no. 1 (2015) : 150-156.

Mizuki Takahashi, Assistant Professor of Biology

The Arizona Toad (Bufo [= Anaxyrus] microscaphus) occupied the entire Agua Fria River drainage in central Arizona until relatively recently. By the 1980s, a close relative, Woodhouse’s Toad (Bufo woodhousii), colonized the lower reaches of the Agua Fria and replaced B. microscaphus at some sites. We tested the hypothesis that habitat disturbance drives replacement of B. microscaphus by B. woodhousii, via hybridization, by examining shifts in the distribution of these toads following the expansion of the Waddell Dam on the lower Agua Fria River in the early 1990s. As of 2010, the high elevation headwaters of the Agua Fria River were still occupied by B. microscaphus, the lower reaches near the confluence with the Gila River were occupied by B. woodhousii, and along the middle reaches, hybridization between these two anurans occurred at the same three sites as documented in the early 1990s. Contrary to expectations, evidence of hybridization along middle reaches of the river is largely unchanged: B. microscaphus has not been replaced by B. woodhousii at any additional sites nor is there any evidence of introgression of woodhousii mtDNA into putatively “pure” microscaphus populations upstream of hybrid sites.

Sullivan, Brian K.; Wooten, Jessica; Schwaner, Terry D.; Sullivan, Keith O.; and Takahashi, Mizuki. “Thirty Years of Hybridization between Toads along the Agua Fria River in Arizona: I. Evidence from Morphology and mtDNA.” Journal of Herpetology 49, no. 1 (2015) : 150-156.

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Friday, February 26th, 2016

Mizuki Takahashi – Okada, Sumio; Fukuda, Yukihiro; and Takahashi, Mizuki. “Paternal Care Behaviors of Japanese Giant Salamander Andrias japonicus in Natural Populations.” Journal of Ethology 33, (2015) : 1-7.

Mizuki Takahashi, Assistant Professor of Biology

Okada, Sumio; Fukuda, Yukihiro; and Takahashi, Mizuki. “Paternal Care Behaviors of Japanese Giant Salamander Andrias japonicus in Natural Populations.” Journal of Ethology 33, (2015) : 1-7.

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Friday, February 26th, 2016

Mizuki Takahashi – Takahashi, Mizuki and McPhee, Carolyn. “Facultative Oviposition of Eastern Newt (Notophthalmus viridescens) in Response to Water Reduction of Aquatic Habitats.” American Midland Naturalist 175, no. 1 (2016) : 73-81.

Mizuki Takahashi, Assistant Professor of Biology

Plastic responses by amphibian larvae to various pond hydroperiods have received much theoretical and empirical attention. In contrast few studies examined maternal plasticity in oviposition in response to different hydroperiods. Using the Eastern Newts as a model, we tested a hypothesis that mothers respond to water reduction of aquatic habitats and alter life history traits such as timing of oviposition, clutch size, and egg size. Alternatively, females may entirely forgo oviposition if aquatic habitats are unsuited for larval survival, in which case we predicted greater body-mass gain of females that forgo oviposition. We daily monitored oviposition of 20 females for 38 d, 10 in constant water treatment and 10 in water reduction treatment. Six females deposited a total of 265 eggs in the constant water treatment whereas only one female deposited 17 eggs in the water reduction treatment, suggesting females facultatively altered oviposition behavior in response to water reduction. Contrary to the prediction, oviposited females gained significantly more body mass, suggesting those females that skipped oviposition stopped vitellogenesis during the experiment; whereas, oviposited females still contained yolk-laden ova at the end of the experiment. We could not test maternal plasticity in timing of oviposition, egg size, and clutch size because only one female from the water reduction treatment deposited eggs. The present study demonstrates that the Eastern Newt is a potentially useful model to further explore maternal plasticity in amphibians.

Takahashi, Mizuki and McPhee, Carolyn. “Facultative Oviposition of Eastern Newt (Notophthalmus viridescens) in Response to Water Reduction of Aquatic Habitats.” American Midland Naturalist 175, no. 1 (2016) : 73-81.

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Friday, February 26th, 2016

Mark F. Haussmann – Fasanello, Vincent; Carlton, Elizabeth; Pott, Maddie; Marchetto, Nicole M.; Vaughn, Emily; McGraw, Kevin; Mauck, Robert A.; and Haussmann, Mark F. “Monomorphic ornamentation related to oxidative damage and assortative mating in the Black Guillemot (Cepphus grylle).” Waterbirds 38, no. 1 (2015) : 106-110.

Mark F. Haussmann, Associate Professor of Biology

The Black Guillemot (Cepphus grylle) is a monomorphic seabird characterized by its muted plumage and bright red feet, which it prominently displays during courtship. Foot color and oxidative stress were analyzed in a Black Guillemot colony at the Bay of Fundy during the 2006 and 2007 breeding seasons. While no relationship between red intensity of feet and carotenoids was uncovered, the level of plasma oxidative damage was negatively correlated with foot color. Additionally, red intensity of male feet was significantly correlated with the red intensity of their mates’ feet, suggesting the possibility of assortative mating by foot color in this species. Further experimental work is necessary to determine whether foot color is used in this species as an honest signal to relay information on the ability of an individual to manage oxidative stress

Fasanello, Vincent; Carlton, Elizabeth; Pott, Maddie; Marchetto, Nicole M.; Vaughn, Emily; McGraw, Kevin; Mauck, Robert A.; and Haussmann, Mark F. “Monomorphic ornamentation related to oxidative damage and assortative mating in the Black Guillemot (Cepphus grylle).” Waterbirds 38, no. 1 (2015) : 106-110.

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Friday, February 26th, 2016

DeeAnn Reeder – Schaer, Juliane; Reeder, DeeAnn; Vodzak, Megan E.; Olival, Kevin J.; Weber, Natalie; Mayer, Frieder; Matuschewski, Kai; and Perkins, Susan L. “Nycteria Parasites of Afrotropical Insectivorous Bats.” International Journal for Parasitology 45, no. 6 (2015) : 375-384.

DeeAnn Reeder, Professor of Biology

Parasitic protozoan parasites have evolved many co-evolutionary paths towards stable transmission to their host population. Plasmodium spp., the causative agents of malaria, and related haemosporidian parasites are dipteran-borne eukaryotic pathogens that actively invade and use vertebrate erythrocytes for gametogenesis and asexual development, often resulting in substantial morbidity and mortality of the infected hosts. Here, we present results of a survey of insectivorous bats from tropical Africa, including new isolates of species of the haemosporidian genus Nycteria. A hallmark of these parasites is their capacity to infect bat species of distinct families of the two evolutionary distant chiropteran suborders. We did detect Nycteria parasites in both rhinolophid and nycterid bat hosts in geographically separate areas of Sub-Saharan Africa, however our molecular phylogenetic analyses support the separation of the parasites into two distinct clades corresponding to their host genera, suggestive of ancient co-divergence and low levels of host switching. For one clade of these parasites, cytochrome b genes could not be amplified and cytochrome oxidase I sequences showed unusually high rates of evolution, suggesting that the mitochondrial genome of these parasites may have either been lost or substantially altered. This haemosporidian parasite-mammalian host system also highlights that sequential population expansion in the liver and gametocyte formation is a successful alternative to intermediate erythrocytic replication cycles. (C) 2015 The Authors. Published by Elsevier Ltd. on behalf of Australian Society for Parasitology Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Schaer, Juliane; Reeder, DeeAnn; Vodzak, Megan E.; Olival, Kevin J.; Weber, Natalie; Mayer, Frieder; Matuschewski, Kai; and Perkins, Susan L. “Nycteria Parasites of Afrotropical Insectivorous Bats.” International Journal for Parasitology 45, no. 6 (2015) : 375-384.

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Friday, February 26th, 2016

Steve Jordan – Giersch, J. Joseph; Jordan, Steve; Luikart, Gordon; Jones, Leslie A.; Hauer, F. Richard; and Muhlfeld, Clint C. “Climate-Induced Range Contraction of a Rare Alpine Aquatic Invertebrate.” Freshwater Science 34, no. 1 (2015) : 53-65.

Steve Jordan, Associate Professor of Biology

Climate warming poses a serious threat to alpine-restricted species worldwide, yet few studies have empirically documented climate-induced changes in distributions. The rare stonefly, Zapada glacier (Baumann and Gaufin), endemic to alpine streams of Glacier National Park (GNP), Montana, was recently petitioned for listing under the US Endangered Species Act because of climate-change-induced glacier loss, yet little was known about its current status and distribution. We resampled streams throughout the historical distribution of Z. glacier to investigate trends in occurrence associated with changes in temperature and glacial extent. The current geographic distribution of the species was assessed using morphological characteristics of adults and DNA barcoding of nymphs. Bayesian phylogenetic analysis of mtDNA data revealed 8 distinct clades of the genus corresponding with 7 known species from GNP, and one potentially cryptic species. Climate model simulations indicate that average summer air temperature increased (0.67-1.00 degrees C) during the study period (1960-2012), and glacial surface area decreased by approximate to 35% from 1966 to 2005. We detected Z. glacier in only 1 of the 6 historically occupied streams and at 2 new locations in GNP. These results suggest that an extremely restricted historical distribution of Z. glacier in GNP has been further reduced over the past several decades by an upstream retreat to higher, cooler sites as water temperatures increased and glacial masses decreased. More research is urgently needed to determine the status, distribution, and vulnerability of Z. glacier and other alpine stream invertebrates threatened by climate change in mountainous ecosystems.

Giersch, J. Joseph; Jordan, Steve; Luikart, Gordon; Jones, Leslie A.; Hauer, F. Richard; and Muhlfeld, Clint C. “Climate-Induced Range Contraction of a Rare Alpine Aquatic Invertebrate.” Freshwater Science 34, no. 1 (2015) : 53-65.

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Friday, February 26th, 2016

Mark F. Haussmann – Lendvai, Adam Z.; Akcay, Caglar; Weiss, Talia; Haussmann, Mark F.; Moore, Ignacio T.; and Bonier, Frances. “Low Cost Audiovisual Playback and Recording Triggered by Radio Frequency Identification Using Raspberry Pi.” PeerJ 4, (2015) : e877.

Mark F. Haussmann, Associate Professor of Biology

Playbacks of visual or audio stimuli to wild animals is a widely used experimental tool in behavioral ecology. In many cases, however, playback experiments are constrained by observer limitations such as the time observers can be present, or the accuracy of observation. These problems are particularly apparent when playbacks are triggered by specific events, such as performing a specific behavior, or are targeted to specific individuals. We developed a low-cost automated playback/recording system, using two field-deployable devices: radio-frequency identification (RFID) readers and Raspberry Pi micro-computers. This system detects a specific passive integrated transponder (PIT) tag attached to an individual, and subsequently plays back the stimuli, or records audio or visual information. To demonstrate the utility of this system and to test one of its possible applications, we tagged female and male tree swallows (Tachycineta bicolor) from two box-nesting populations with PIT tags and carried out playbacks of nestling begging calls every time focal females entered the nestbox over a six-hour period. We show that the RFID-Raspberry Pi system presents a versatile, low-cost, field-deployable system that can be adapted for many audio and visual playback purposes. In addition, the set-up does not require programming knowledge, and it easily customized to many other applications, depending on the research questions. Here, we discuss the possible applications and limitations of the system. The low cost and the small learning curve of the RFID-Raspberry Pi system provides a powerful new tool to field biologists.

Lendvai, Adam Z.; Akcay, Caglar; Weiss, Talia; Haussmann, Mark F.; Moore, Ignacio T.; and Bonier, Frances. “Low Cost Audiovisual Playback and Recording Triggered by Radio Frequency Identification Using Raspberry Pi.” PeerJ 4, (2015) : e877.

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Friday, February 26th, 2016

DeeAnn Reeder – Pearson, Brandon L.; Reeder, DeeAnn; and Judge, Peter G. “Crowding Increases Salivary Cortisol But Not Self-Directed Behavior in Captive Baboons.” International Journal of Primatology (2015).

DeeAnn Reeder, Professor of Biology

Reduced space can lead to crowding in social animals. Crowding increases the risk of agonistic interactions that, in turn, may require additional physiological defensive coping mechanisms affecting health. To determine the stress induced from increased social density in a group of nineteen baboons living in an indoor/outdoor enclosure, saliva cortisol levels and rates of anxiety-related behavior were analyzed across two unique crowding episodes. Initially, mean salivary cortisol levels when animals were restricted to their indoor quarters were compared to those when they also had access to their larger outdoor enclosure. Then, mean cortisol levels were compared before, during, and after two distinct crowding periods of long and short duration. Crowding resulted in significantly elevated cortisol during crowding periods compared to non-crowded periods. Cortisol levels returned to baseline following two crowding episodes contrasting in their length and ambient climate conditions. These cortisol elevations indicate greater metabolic costs of maintaining homeostasis under social stress resulting from reduced space. Self-directed behavior, conversely, was not reliably elevated during crowding. Results suggest that the potential for negative social interactions, and/or the uncertainty associated with social threat can cause physiological stress responses detected by salivary cortisol. Self-directed behavioral measures of stress may constitute inadequate indicators of social stress in colony-housed monkeys or represent subjective emotional arousal unrelated to hypothalamic-pituitary adrenal axis activation.

Pearson, Brandon L.; Reeder, DeeAnn; and Judge, Peter G. “Crowding Increases Salivary Cortisol But Not Self-Directed Behavior in Captive Baboons.” International Journal of Primatology (2015).

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Friday, February 26th, 2016

Joseph S. Johnson – Grieneisen, Laura E.; Brownlee-Bouboulis, Sarah A.; Johnson, Joseph S.; and Reeder, DeeAnn. “Sex and Hibernaculum Temperature Predict Survivorship in White-Nose Syndrome Affected Little Brown Myotis (Myotis lucifugus).” Royal Society Open Science 2, (2015) : 140470.

Joseph S. Johnson, Visiting Assistant Professor of Biology

White-nose syndrome (WNS), an emerging infectious disease caused by the novel fungusPseudogymnoascus destructans, has devastated North American bat populations since its discovery in 2006. The little brown myotis, Myotis lucifugus, has been especially affected. The goal of this 2-year captive study was to determine the impact of hibernacula temperature and sex on WNS survivorship in little brown myotis that displayed visible fungal infection when collected from affected hibernacula. In study 1, we found that WNS-affected male bats had increased survival over females and that bats housed at a colder temperature survived longer than those housed at warmer temperatures. In study 2, we found that WNS-affected bats housed at a colder temperature fared worse than unaffected bats. Our results demonstrate that WNS mortality varies among individuals, and that colder hibernacula are more favourable for survival. They also suggest that female bats may be more negatively affected by WNS than male bats, which has important implications for the long-term survival of the little brown myotis in eastern North America.

Grieneisen, Laura E.; Brownlee-Bouboulis, Sarah A.; Johnson, Joseph S.; and Reeder, DeeAnn. “Sex and Hibernaculum Temperature Predict Survivorship in White-Nose Syndrome Affected Little Brown Myotis (Myotis lucifugus).” Royal Society Open Science 2, (2015) : 140470.

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Friday, February 26th, 2016

Mark F. Haussmann – Gilmour, Morgan; Lattin, Christine; Romero, Michael; Haussmann, Mark F.; Mauck, Robert A.; and Dearborn, Donald C. “Finding the Best Predictor of Reproductive Performance of Leach’s Storm-Petrels.” Auk: Ornithological Advances 132, (2015) : 191-205.

Mark F. Haussmann, Associate Professor of Biology

Physiological and environmental factors shape foraging strategies and energy balance. For species that breed seasonally, physiological changes in an individual can have short-term effects, but also can persist as carry-over effects from one season to the next, such as from the overwintering season to the breeding season. We tested the hypothesis that reproductive performance could be predicted by diet and energy balance during the breeding and nonbreeding seasons in a long-lived seabird, the Leach’s Storm-Petrel (Oceanodroma leucorhoa). Specifically, we predicted that better reproductive performance would be correlated with four factors: (1) a high-lipid diet, as indexed by a high C:N ratio in stable isotope analyses; (2) a diet rich in antioxidants, as indexed by high plasma antioxidant capacity; (3) foraging at a high trophic level, as indexed by high values of δ15N in stable isotope analyses, which is positively related to lipids; and (4) a positive long-term energy balance, revealed by low levels of corticosterone in feathers. Because of our interest in short-term effects vs. carry-over effects, stable isotope values were measured from two different tissue sources: erythrocytes, to test for short-term effects, and winter-grown feathers, to test for carry-over effects. We monitored reproductive performance through egg volume, chick growth, parental provisioning, and fledging success. Parents with more breeding experience were more likely to have a successful nest in 2010, but not in 2009. Individuals exhibited consistent egg volume and nonbreeding season feather δ15N values across the 2 years of our study, but, overall, neither diet nor feather corticosterone predicted reproductive performance. Nonetheless, our simple, noninvasive measures of breeding performance could be applied to other species to study life-history strategies and energy balance.

Gilmour, Morgan; Lattin, Christine; Romero, Michael; Haussmann, Mark F.; Mauck, Robert A.; and Dearborn, Donald C. “Finding the Best Predictor of Reproductive Performance of Leach’s Storm-Petrels.” Auk: Ornithological Advances 132, (2015) : 191-205.

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Friday, February 26th, 2016

DeeAnn Reeder – Johnson, Joseph S.; Reeder, DeeAnn M.; Lilley, Thomas M.; and Field, Ken. “Antibodies to Pseudogymnoascus destructans Are Not Sufficient for Protection Against White-Nose Syndrome.” Ecology and Evolution (2015).

DeeAnn Reeder, Professor of Biology

White-nose syndrome (WNS) is a fungal disease caused by Pseudogymnoascus destructans (Pd) that affects bats during hibernation. Although millions of bats have died from WNS in North America, mass mortality has not been observed among European bats infected by the fungus, leading to the suggestion that bats in Europe are immune. We tested the hypothesis that an antibody-mediated immune response can provide protection against WNS by quantifying antibod- ies reactive to Pd in blood samples from seven species of free-ranging bats in North America and two free-ranging species in Europe. We also quantified antibodies in blood samples from little brown myotis (Myotis lucifugus) that were part of a captive colony that we injected with live Pd spores mixed with adjuvant, as well as individuals surviving a captive Pd infection trial. Seropreva- lence of antibodies against Pd, as well as antibody titers, was greater among lit- tle brown myotis than among four other species of cave-hibernating bats in North America, including species with markedly lower WNS mortality rates. Among little brown myotis, the greatest titers occurred in populations occupy- ing regions with longer histories of WNS, where bats lacked secondary symp- toms of WNS. We detected antibodies cross-reactive with Pd among little brown myotis na€ıve to the fungus. We observed high titers among captive little brown myotis injected with Pd. We did not detect antibodies against Pd in Pd- infected European bats during winter, and titers during the active season were lower than among little brown myotis. These results show that antibody-medi- ated immunity cannot explain survival of European bats infected with Pd and that little brown myotis respond differently to Pd than species with higher WNS survival rates. Although it appears that some species of bats in North America may be developing resistance to WNS, an antibody-mediated immune response does not provide an explanation for these remnant populations.

Johnson, Joseph S.; Reeder, DeeAnn M.; Lilley, Thomas M.; and Field, Ken. “Antibodies to Pseudogymnoascus destructans Are Not Sufficient for Protection Against White-Nose Syndrome.” Ecology and Evolution (2015).

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Friday, February 26th, 2016

Joseph S. Johnson – Johnson, Joseph S.; Reeder, DeeAnn M.; Lilley, Thomas M.; and Field, Ken. “Antibodies to Pseudogymnoascus destructans Are Not Sufficient for Protection Against White-Nose Syndrome.” Ecology and Evolution (2015 ).

Joseph S. Johnson, Visiting Assistant Professor of Biology

White-nose syndrome (WNS) is a fungal disease caused by Pseudogymnoascus destructans (Pd) that affects bats during hibernation. Although millions of bats have died from WNS in North America, mass mortality has not been observed among European bats infected by the fungus, leading to the suggestion that bats in Europe are immune. We tested the hypothesis that an antibody-mediated immune response can provide protection against WNS by quantifying antibod- ies reactive to Pd in blood samples from seven species of free-ranging bats in North America and two free-ranging species in Europe. We also quantified antibodies in blood samples from little brown myotis (Myotis lucifugus) that were part of a captive colony that we injected with live Pd spores mixed with adjuvant, as well as individuals surviving a captive Pd infection trial. Seropreva- lence of antibodies against Pd, as well as antibody titers, was greater among lit- tle brown myotis than among four other species of cave-hibernating bats in North America, including species with markedly lower WNS mortality rates. Among little brown myotis, the greatest titers occurred in populations occupy- ing regions with longer histories of WNS, where bats lacked secondary symp- toms of WNS. We detected antibodies cross-reactive with Pd among little brown myotis na€ıve to the fungus. We observed high titers among captive little brown myotis injected with Pd. We did not detect antibodies against Pd in Pd- infected European bats during winter, and titers during the active season were lower than among little brown myotis. These results show that antibody-medi- ated immunity cannot explain survival of European bats infected with Pd and that little brown myotis respond differently to Pd than species with higher WNS survival rates. Although it appears that some species of bats in North America may be developing resistance to WNS, an antibody-mediated immune response does not provide an explanation for these remnant populations.

Johnson, Joseph S.; Reeder, DeeAnn M.; Lilley, Thomas M.; and Field, Ken. “Antibodies to Pseudogymnoascus destructans Are Not Sufficient for Protection Against White-Nose Syndrome.” Ecology and Evolution (2015 ).

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Friday, February 26th, 2016

DeeAnn Reeder – Ammon, Brian R.; Albarino, Cesar G.; Bird, Brian H.; Nyakarahuka, Luke; Sealy, Tara K.; Balinandi, Stephen; Schuh, Amy J.; Campbell, Shelly M.; Stroher, Ute; Jones, Megan E.B.; Vodzack, Megan E.; Reeder, DeeAnn; Kaboyo, Winyi; Nichol, Stuart T.; and Towner, Jonathan S. “A Recently Discovered Pathogenic Paramyxovirus, Sosuga Virus, is Present in Rousettus aegyptiacus Fruit Bats at Multiple Locations in Uganda.” Journal of Wildlife Diseases 51, no. 3 (2015) : 774-779.

DeeAnn Reeder, Professor of Biology

In August 2012, a wildlife biologist became ill immediately following a 6-wk field trip to collect bats and rodents in South Sudan and Uganda. After returning to the US, the biologist was admitted to the hospital with multiple symptoms including fever, malaise, headache, generalized myalgia and arthralgia, stiffness in the neck, and sore throat. Soon after admission, the patient developed a maculopapular rash and oropharynx ulcerations. The patient remained hospitalized for 14 d. Several suspect pathogens, including viral hemorrhagic fever viruses such as Ebola viruses and Marburg viruses, were ruled out through standard diagnostic testing. However, deep sequencing and metagenomic analyses identified a novel paramyxovirus, later named Sosuga virus, in the patient’s blood. To determine the potential source, bat tissues collected during the 3-wk period just prior to the onset of symptoms were tested for Sosuga virus, and several Egyptian rousette bats (Rousettus aegyptiacus) were found to be positive. Further analysis of archived Egyptian rousette tissues collected at other localities in Uganda found additional Sosuga virus positive bats, suggesting this species could be a potential natural reservoir for this novel paramyxovirus.

Ammon, Brian R.; Albarino, Cesar G.; Bird, Brian H.; Nyakarahuka, Luke; Sealy, Tara K.; Balinandi, Stephen; Schuh, Amy J.; Campbell, Shelly M.; Stroher, Ute; Jones, Megan E.B.; Vodzack, Megan E.; Reeder, DeeAnn; Kaboyo, Winyi; Nichol, Stuart T.; and Towner, Jonathan S. “A Recently Discovered Pathogenic Paramyxovirus, Sosuga Virus, is Present in Rousettus aegyptiacus Fruit Bats at Multiple Locations in Uganda.” Journal of Wildlife Diseases 51, no. 3 (2015) : 774-779.

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Friday, February 26th, 2016

Matthew B. Heintzelman – Heintzelman, Matthew B. “Gliding Motility in Apicomplexan Parasites.” Seminars in Cell & Developmental Biology 46, (2015) : 135-142.

Matthew B. Heintzelman, Associate Professor of Biology

Apicomplexan parasites, including Plasmodium and Toxoplasma, employ a unique form of substrate-dependent locomotion known as gliding motility. In these obligate, intracellular parasites, gliding motility is used for migration through the tissues and cells of the host, for active penetration of the host cell, and, at times, for proactive egress from the host. Gliding motility is powered by an actin-myosin based motor apparatus, known as the glideosome, which is situated within the elaborate cortical domain of the parasite. In this system, myosin is anchored to an internal membrane complex and drives the rearward translocation of actin-associated cell surface adhesins, thus leading to forward movement of the parasite. This review outlines our current understanding of glideosome architecture and the molecular basis of parasite motility. (C) 2015 Elsevier Ltd. All rights reserved.

Heintzelman, Matthew B. “Gliding Motility in Apicomplexan Parasites.” Seminars in Cell & Developmental Biology 46, (2015) : 135-142.

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Friday, February 26th, 2016

Mark F. Haussmann – Wilsterman, Kathryn; Mast, Andrew D.; Luu, Thuyvan H.; and Haussmann, Mark F. “The Timing of Embryonic Exposure to Elevated Temperature Alters Stress Endocrinology in Domestic Chickens (Gallus domesticus).” General and Comparative Endocrinology 212, (2015) : 10-16.

Mark F. Haussmann, Associate Professor of Biology

Patterns of glucocorticoid (GC) release in response to stimuli vary both among individuals and within individuals across their lifetime. While much work has focused on how the prenatal steroid environment can affect GC release, relatively little is known about how environmental parameters, such as incubation temperature affect GCs. We tested the hypothesis that variation and timing of elevated incubation temperature within the thermoneutral zone can alter the pattern of GC release. We incubated domestic chicken eggs (Gallus domesticus) at the optimal incubation temperature (37.5°C) or at a slightly higher temperature (+1.1°C) either early, late, or throughout incubation. At three weeks post-hatch, all birds were (i) exposed to a capture-restraint stress to measure stress-induced GC release (naive). Three days following the naive stressor, birds were (ii) exposed to a heat challenge, which was followed the next day by a second capture-restraint stress (post-heat challenge). Regardless of treatment, birds had similar patterns of GC release following the naive stress series. However, during the post-heat challenge stress series, birds incubated at optimal temperatures increased their peak GC release. In contrast, birds exposed to slightly elevated temperatures for any period of development failed to increase peak GC release, and their specific response varied with timing of exposure to the elevated incubation temperature. Our results demonstrate that subtle variation in the embryonic environment, such as elevated incubation temperature within the thermoneutral zone, can impact the pattern of GC release of offspring. Further work is needed to understand the mechanisms underlying these changes and the relationship between fitness and environmentally-altered phenotypes.

Copyright 2015 Elsevier Inc. All rights reserved.

Wilsterman, Kathryn; Mast, Andrew D.; Luu, Thuyvan H.; and Haussmann, Mark F. “The Timing of Embryonic Exposure to Elevated Temperature Alters Stress Endocrinology in Domestic Chickens (Gallus domesticus).” General and Comparative Endocrinology 212, (2015) : 10-16.

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Friday, February 26th, 2016

Leocadia V. Paliulis – Paliulis, Leocadia V.; Curry, M.M.; Welch, K.D.; Harwood, J.D.; and White, J.A. “Multiple Endosymbiont Infections and Reproductive Manipulations in a Linyphiid Spider Population.” Heredity 115, no. 2 (2015) : 146-152.

Leocadia V. Paliulis, Associate Professor of Biology

In many arthropods, maternally inherited endosymbiotic bacteria can increase infection frequency by manipulating host reproduction. Multiple infections of different bacteria in a single host population are common, yet few studies have documented concurrent endosymbiont phenotypes or explored their potential interactions. We hypothesized that spiders might be a particularly useful taxon for investigating endosymbiont interactions, because they are host to a plethora of endosymbiotic bacteria and frequently exhibit multiple infections. We established two matrilines from the same population of the linyphiid spider Mermessus fradeorum and then used antibiotic curing and controlled mating assays to demonstrate that each matriline was subject to a distinct endosymbiotic reproductive manipulation. One matriline was co-infected with Rickettsia and Wolbachia and produced offspring with a radical female bias. Antibiotic treatment eliminated both endosymbionts and restored an even sex ratio to subsequent generations. Chromosomal and fecundity observations suggest a feminization mechanism. In the other matriline, a separate factorial mating assay of cured and infected spiders demonstrated strong cytoplasmic incompatibility (CI) induced by a different strain of Wolbachia. However, males with this Wolbachia induced only mild CI when mated with the Rickettsia-Wolbachia females. In a subsequent survey of a field population of M. fradeorum, we detected these same three endosymbionts infecting 55% of the spiders in almost all possible combinations, with nearly half of the infected spiders exhibiting multiple infection. Our results suggest that a dynamic network of endosymbionts may interact both within multiply infected hosts and within a population subject to multiple strong reproductive manipulations.

Paliulis, Leocadia V.; Curry, M.M.; Welch, K.D.; Harwood, J.D.; and White, J.A. “Multiple Endosymbiont Infections and Reproductive Manipulations in a Linyphiid Spider Population.” Heredity 115, no. 2 (2015) : 146-152.

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Friday, February 26th, 2016

Mark F. Haussmann – Haussmann, Mark F. and Heidinger, Britt J. “Telomere Dynamics May Link Stress Exposure and Ageing across Generations.” Biology Letters 11, no. 11 (2015 ).

Mark F. Haussmann, Associate Professor of Biology

Although exposure to stressors is known to increase disease susceptibility and accelerate ageing, evidence is accumulating that these effects can span more than one generation. Stressors experienced by parents have been reported to negatively influence the longevity of their offspring and even grand offspring. The mechanisms underlying these long-term, cross-generational effects are still poorly understood, but we argue here that telomere dynamics are likely to play an important role. In this review, we begin by surveying the current connections between stress and telomere dynamics. We then lay out the evidence that exposure to stressors in the parental generation influences telomere dynamics in offspring and potentially subsequent generations. We focus on evidence in mammalian and avian studies and highlight several promising areas where our understanding is incomplete and future investigations are critically needed. Understanding the mechanisms that link stress exposure across generations requires interdisciplinary studies and is essential to both the biomedical community seeking to understand how early adversity impacts health span and evolutionary ecologists interested in how changing environmental conditions are likely to influence age-structured population dynamics.

2015 The Author(s).

Haussmann, Mark F. and Heidinger, Britt J. “Telomere Dynamics May Link Stress Exposure and Ageing across Generations.” Biology Letters 11, no. 11 (2015 ).

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Friday, February 26th, 2016

Ken Field – Field, Ken; Johnson, Joseph S.; Lilley, Thomas M.; Reeder, Sophia M.; Rogers, Elizabeth J.; Behr, Melissa J.; and Reeder, DeeAnn M. “The White-Nose Syndrome Transcriptome: Activation of Anti-fungal Host Responses in Wing Tissue of Hibernating Little Brown Myotis.” PLOS Pathogens 11, no. 10 (2015) : e1005168.

Ken Field, Associate Professor of Biology

White-nose syndrome (WNS) in North American bats is caused by an invasive cutaneous infection by the psychrophilic fungus Pseudogymnoascus destructans (Pd). We compared transcriptome-wide changes in gene expression using RNA-Seq on wing skin tissue from hibernating little brown myotis (Myotis lucifugus) with WNS to bats without Pd exposure. We found that WNS caused significant changes in gene expression in hibernating bats including pathways involved in inflammation, wound healing, and metabolism. Local acute inflammatory responses were initiated by fungal invasion. Gene expression was increased for inflammatory cytokines, including interleukins (IL) IL-1 beta, IL-6, IL-17C, IL-20, IL-23A, IL-24, and G-CSF and chemokines, such as Ccl2 and Ccl20. This pattern of gene expression changes demonstrates that WNS is accompanied by an innate anti-fungal host response similar to that caused by cutaneous Candida albicans infections. However, despite the apparent production of appropriate chemokines, immune cells such as neutrophils and T cells do not appear to be recruited. We observed upregulation of acute inflammatory genes, including prostaglandin G/H synthase 2 (cyclooxygenase-2), that generate eicosanoids and other nociception mediators. We also observed differences in Pd gene expression that suggest host-pathogen interactions that might determine WNS progression. We identified several classes of potential virulence factors that are expressed in Pd during WNS, including secreted proteases that may mediate tissue invasion. These results demonstrate that hibernation does not prevent a local inflammatory response to Pd infection but that recruitment of leukocytes to the site of infection does not occur. The putative virulence factors may provide novel targets for treatment or prevention of WNS. These observations support a dual role for inflammation during WNS; inflammatory responses provide protection but excessive inflammation may contribute to mortality, either by affecting torpor behavior or causing damage upon emergence in the spring.

Field, Ken; Johnson, Joseph S.; Lilley, Thomas M.; Reeder, Sophia M.; Rogers, Elizabeth J.; Behr, Melissa J.; and Reeder, DeeAnn M. “The White-Nose Syndrome Transcriptome: Activation of Anti-fungal Host Responses in Wing Tissue of Hibernating Little Brown Myotis.” PLOS Pathogens 11, no. 10 (2015) : e1005168.

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Friday, February 26th, 2016

Leocadia V. Paliulis – Brady, Mary and Paliulis, Leocadia V. “Chromosome Interaction over a Distance in Meiosis.” Royal Society Open Science 2, no. 2 (2015) : 150029.

Leocadia V. Paliulis, Associate Professor of Biology

The challenge of cell division is to distribute partner chromosomes (pairs of homologues, pairs of sex chromosomes or pairs of sister chromatids) correctly, one into each daughter cell. In the ‘standard’ meiosis, this problem is solved by linking partners together via a chiasma and/or sister chromatid cohesion, and then separating the linked partners from one another in anaphase; thus, the partners are kept track of, and correctly distributed. Many organisms, however, properly separate chromosomes in the absence of any obvious physical connection, and movements of unconnected partner chromosomes are coordinated at a distance. Meiotic distance interactions happen in many different ways and in different types of organisms. In this review, we discuss several different known types of distance segregation and propose possible explanations for non-random segregation of distance-segregating chromosomes.

Brady, Mary and Paliulis, Leocadia V. “Chromosome Interaction over a Distance in Meiosis.” Royal Society Open Science 2, no. 2 (2015) : 150029.

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