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Friday, February 26th, 2016

Ken Field – 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).

Ken Field, Associate 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 – 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

Z. Morgan Benowitz-Fredericks – Benowitz-Fredericks, Z. Morgan; Schultner, Jannik; and Kitaysky, Alexander S. “Effects of Prenatal Environment Are Revealed by Post-natal Challenges: Embryonic Hormone Exposure, Adrenocortical Function and Food in Seabird Chicks.” Physiological And Biochemical Zoology 88, no. 6 (2015) : 607-623.

Z. Morgan Benowitz-Fredericks, Assistant Professor of Biology

The interaction between prenatal environments and postnatal environments is an important source of phenotypic variability. We examined the ability of prenatal steroid exposure and postnatal energy restriction to explain adrenocortical function and fledging age in captive seabird chicks. We proposed and tested two hypotheses: (1) the strength of prenatal effects is attenuated by challenging postnatal environments (postnatal override) and (2) the strength of prenatal effects increases with the severity of postnatal challenges (postnatal reveal). We reared common murre (Uria aalge) chicks and measured prenatal exposure to corticosterone (CORT) and testosterone (T) from allantoic waste. Adrenocortical function was assessed after 10 d of ad lib. feeding and then after 5 and 10 d on controlled diets. Postnatal override predicts that prenatal steroids will explain more phenotypic variation before implementation of energy restriction; postnatal reveal predicts that the contribution of prenatal steroids will increase with duration and severity of energy restriction. Energy restriction increased secretion of baseline CORT and the adrenocortical response to the standardized stressor of handling and restraint. The ability of prenatal steroids to explain baseline CORT increased with duration of energy restriction, and for day 20 free baseline CORT, there was a significant interaction between kilojoules per day and prenatal CORT levels; severity of restriction strengthened the relationship between prenatal hormone levels and postnatal hormone levels. Both maximum CORT at day 20 and fledging age were best explained by diet treatment and day 15 or day 20 baseline CORT, respectively. Overall, prenatal CORT increased fledging age and baseline secretion of CORT, while prenatal T decreased them. However, prenatal effects on adrenocortical function were apparent only under the energy restriction conditions. Thus, we found some support for the postnatal reveal hypothesis; our results suggest that some prenatal effects on phenotype may be more likely to manifest in challenging postnatal environments.

Benowitz-Fredericks, Z. Morgan; Schultner, Jannik; and Kitaysky, Alexander S. “Effects of Prenatal Environment Are Revealed by Post-natal Challenges: Embryonic Hormone Exposure, Adrenocortical Function and Food in Seabird Chicks.” Physiological And Biochemical Zoology 88, no. 6 (2015) : 607-623.

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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

Warren G. Abrahamson III – Dorchin, Netta; Joy, Jeffrey B.; Hilke, Lukas K.; Wise, Michael J.; and Abrahamson, Warren G. II. “Taxonomy and Phylogeny of the Asphondylia Species (Diptera: Cecidomyiidae) of North American Goldenrods: Challenging Morphology, Complex Host Associations, and Cryptic Speciation.” Zoological Journal of the Linnean Society 174, no. 2 (2015) : 265-304.

Warren G. Abrahamson III, Professor of Biology Emeritus

Reproductive isolation and speciation in herbivorous insects may be accomplished via shifts between host-plant resources: either plant species or plant organs. The intimate association between gall-inducing insects and their host plants makes them particularly useful models in the study of speciation. North American goldenrods (Asteraceae: Solidago and Euthamia) support a rich fauna of gall-inducing insects. Although several of these insects have been the subject of studies focusing on speciation and tritrophic interactions, others remain unstudied and undescribed. Among the latter are at least seven species of the large, cosmopolitan gall midge genus AsphondyliaLoew (Diptera: Cecidomyiidae), the taxonomy and biology of which are elucidated here for the first time using morphological, molecular, and life-history data. We describe Asphondylia pseudorosasp.nov., Asphondylia rosulatasp.nov., and Asphondylia silvasp.nov., and redescribe Asphondylia monachaOsten Sacken, 1869 and Asphondylia solidaginisBeutenmuller, 1907, using morphological characters of adults, immature stages, and galls, as well as sequence data from both nuclear and mitochondrial genes. A neotype is designated for A.solidaginis, the type series of which is considered lost. We also provide information on the life history of all species, including a description of two inquilinous cecidomyiids commonly found in the galls, Clinodiplosis comitissp.nov. and Youngomyia podophyllae (Felt, 1907), and on parasitoid wasps associated with the gall midges. Asphondylia johnsoni Felt, 1908, which was described from an unknown gall on an unknown Solidago host, is assigned to nomina dubia. Our phylogenetic analyses show that some of the Asphondylia species associated with goldenrods induce two different types of galls during their life cycle, some exhibit host alterations, and some do both. In the absence of reliable morphological differences, recognising species boundaries and deciphering host associations of species must rely heavily on molecular data. Our analysis suggests that radiation in this group has been recent and occurred through shifts among host plants.(c) 2015 The Linnean Society of London

Dorchin, Netta; Joy, Jeffrey B.; Hilke, Lukas K.; Wise, Michael J.; and Abrahamson, Warren G. II. “Taxonomy and Phylogeny of the Asphondylia Species (Diptera: Cecidomyiidae) of North American Goldenrods: Challenging Morphology, Complex Host Associations, and Cryptic Speciation.” Zoological Journal of the Linnean Society 174, no. 2 (2015) : 265-304.

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Friday, February 26th, 2016

Tristan Stayton – Stayton, Tristan. “The Definition, Recognition, and Interpretation of Convergent Evolution, and Two New Measures for Quantifying and Assessing the Significance of Convergence.” Evolution69, no. 8 (2015) : 2140-2153.

Tristan Stayton, Associate Professor of Biology

Convergent evolution is an important phenomenon in the history of life. Despite this, there is no common definition of convergence used by biologists. Instead, several conceptually different definitions are employed. The primary dichotomy is between pattern-based definitions, where independently evolved similarity is sufficient for convergence, and process-based definitions, where convergence requires a certain process to produce this similarity. The unacknowledged diversity of definitions can lead to problems in evolutionary research. Process-based definitions may bias researchers away from studying or recognizing other sources of independently evolved similarity, or lead researchers to interpret convergent patterns as necessarily caused by a given process. Thus, pattern-based definitions are recommended. Existing measures of convergence are reviewed, and two new measures are developed. Both are pattern based and conceptually minimal, quantifying nothing but independently evolved similarity. One quantifies the amount of phenotypic distance between two lineages that is closed by subsequent evolution; the other simply counts the number of lineages entering a region of phenotypic space. The behavior of these measures is explored in simulations; both show acceptable Type I and Type II error. The study of convergent evolution will be facilitated if researchers are explicit about working definitions of convergence and adopt a standard toolbox of convergence measures.

Stayton, Tristan. “The Definition, Recognition, and Interpretation of Convergent Evolution, and Two New Measures for Quantifying and Assessing the Significance of Convergence.” Evolution69, no. 8 (2015) : 2140-2153.

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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

DeeAnn Reeder – 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.

DeeAnn Reeder, 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 – 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

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

Mark F. Haussmann – Ouyang, J. Q.; Lendvai, A. Z.; Dakin, R.; Domalik, A. D.; Fasanello, V. J.; Vassallo, B. G.; Haussmann, Mark F.; Moore, I. T.; and Bonier, F. “Weathering the Storm: Parental Effort and Experimental Manipulation of Stress Hormones Predict Brood Survival.” BMC Evolutionary Biology 15, no. 219 (2015 ).

Mark F. Haussmann, Associate Professor of Biology

Background: Unpredictable and inclement weather is increasing in strength and frequency, challenging organisms to respond adaptively. One way in which animals respond to environmental challenges is through the secretion of glucocorticoid stress hormones. These hormones mobilize energy stores and suppress non-essential physiological and behavioral processes until the challenge passes. To investigate the effects of glucocorticoids on reproductive decisions, we experimentally increased corticosterone levels (the primary glucocorticoid in birds) in free-living female tree swallows, Tachycineta bicolor, during the chick-rearing stage. Due to an unprecedented cold and wet breeding season, 90 % of the nests in our study population failed, which created a unique opportunity to test how challenging environmental conditions interact with the physiological mechanisms underlying life-history trade-offs. Results: We found that exogenous corticosterone influenced the regulation of parental decisions in a contextdependent manner. Control and corticosterone-treated females had similar brood failure rates under unfavorable conditions (cold and rainy weather), but corticosterone treatment hastened brood mortality under more favorable conditions. Higher female nest provisioning rates prior to implantation were associated with increased probability of brood survival for treatment and control groups. However, higher pre-treatment male provisioning rates were associated with increased survival probability in the control group, but not the corticosterone-treated group. Conclusions: These findings reveal complex interactions between weather, female physiological state, and partner parental investment. Our results also demonstrate a causal relationship between corticosterone concentrations and individual reproductive behaviors, and point to a mechanism for why naturally disturbed populations, which experience multiple stressors, could be more susceptible and unable to respond adaptively to changing environmental conditions.

Ouyang, J. Q.; Lendvai, A. Z.; Dakin, R.; Domalik, A. D.; Fasanello, V. J.; Vassallo, B. G.; Haussmann, Mark F.; Moore, I. T.; and Bonier, F. “Weathering the Storm: Parental Effort and Experimental Manipulation of Stress Hormones Predict Brood Survival.” BMC Evolutionary Biology 15, no. 219 (2015 ).

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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

Mark F. Haussmann – Fletcher, Kelsey L.; Whitley, Brittany N.; Treidel, Lisa A.; Thompson, David; Williams, Annie; Noguera, Jose C.; Stevenson, Jennie; and Haussmann, Mark F. “Voluntary Locomotor Activity Mitigates Oxidative Damage Associated with Isolation Stress in the Prairie Vole (Microtus ochrogaster).” Biology Letters 11, no. 7 (2015 ).

Mark F. Haussmann, Associate Professor of Biology

Organismal performance directly depends on an individual’s ability to cope with a wide array of physiological challenges. For social animals, social isolation is a stressor that has been shown to increase oxidative stress. Another physiological challenge, routine locomotor activity, has been found to decrease oxidative stress levels. Because we currently do not have a good understanding of how diverse physiological systems like stress and locomotion interact to affect oxidative balance, we studied this interaction in the prairie vole (Microtus ochrogaster). Voles were either pair housed or isolated and within the isolation group, voles either had access to a moving wheel or a stationary wheel. We found that chronic periodic isolation caused increased levels of oxidative stress. However, within the vole group that was able to run voluntarily, longer durations of locomotor activity were associated with less oxidative stress. Our work suggests that individuals who demonstrate increased locomotor activity may be better able to cope with the social stressor of isolation.

2015 The Author(s) Published by the Royal Society. All rights reserved.

Fletcher, Kelsey L.; Whitley, Brittany N.; Treidel, Lisa A.; Thompson, David; Williams, Annie; Noguera, Jose C.; Stevenson, Jennie; and Haussmann, Mark F. “Voluntary Locomotor Activity Mitigates Oxidative Damage Associated with Isolation Stress in the Prairie Vole (Microtus ochrogaster).” Biology Letters 11, no. 7 (2015 ).

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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

Mark F. Haussmann – Monaghan, Pat and Haussmann, Mark F. “The Positive and Negative Consequences of Stressors during Early Life.” Early Human Development 91, no. 11 (2015) : 643-647.

Mark F. Haussmann, Associate Professor of Biology

We discuss the long-term effects of stress exposure in pre- and early postnal life. We present an evolutionary framework within which such effects can be viewed, and describe how the outcomes might vary with species life histories. We focus on stressors that induce increases in glucocorticoid hormones and discuss the advantages of an experimental approach. We describe a number of studies demonstrating how exposure to these hormones in early life can influence stress responsiveness and have substantial long-term, negative consequences for adult longevity. We also describe how early life exposure to mild levels of stressors can have beneficial effects on resilience to stress in later life, and discuss how the balance of costs and benefits is likely dependent on the nature of the adult environment (C) 2015 Elsevier Ireland Ltd. All rights reserved.

Monaghan, Pat and Haussmann, Mark F. “The Positive and Negative Consequences of Stressors during Early Life.” Early Human Development 91, no. 11 (2015) : 643-647.

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