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expectations, evidence of hybridization along middle reaches of the river is largely unchanged: B. microscaphus has not been replaced by B. woodhousii at any additional sites nor is there any evidence of introgression of woodhousii mtDNA into putatively “pure” microscaphus populations upstream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 – 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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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

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

Leocadia V. Paliulis – Paliulis, Leocadia V.; Fabig, Gunar; and Müller-Reichert, Thomas. “Back to the Roots: Segregation of Univalent Sex Chromosomes in Meiosis.” Chromosoma (2015 ).

Leocadia V. Paliulis, Associate Professor of Biology

In males of many taxa, univalent sex chromosomes normally segregate during the first meiotic division, and analysis of sex chromosome segregation was foundational for the chromosome theory of inheritance. Correct segregation of single or multiple univalent sex chromosomes occurs in a cellular environment where every other chromosome is a bivalent that is being partitioned into homologous chromosomes at anaphase I. The mechanics of univalent chromosome segregation vary among animal taxa. In some, univalents establish syntelic attachment of sister kinetochores to the spindle. In others, amphitelic attachment is established. Here, we review how this problem of segregation of unpaired chromosomes is solved in different animal systems. In addition, we give a short outlook of how mechanistic insights into this process could be gained by explicitly studying model organisms, such as Caenorhabditis elegans.

Paliulis, Leocadia V.; Fabig, Gunar; and Müller-Reichert, Thomas. “Back to the Roots: Segregation of Univalent Sex Chromosomes in Meiosis.” Chromosoma (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

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

Matthew McTammany – Wilson, Matthew J.; McTammany, Matthew; Bilger, Michael D.; Reese, Sean; and Hayes, Benjamin R. “Combining Data from Multiple Agencies to Assess Benthic Macroinvertebrate Communities in a Large Gravel-Bed River.” Freshwater Science 34, no. 2 (2015) : 593-605.

Matthew McTammany, Associate Professor of Biology & Environmental Studies

Government agencies frequently conduct benthic macroinvertebrate surveys for bioassessment at large spatial scales in a variety of aquatic habitats, including large rivers. However, these data are rarely used by investigators outside the specific regulatory agency. We used data from 150 benthic macroinvertebrate samples collected over a period of 20 y from 10 locations in a large, shallow river system (the Susquehanna River and 2 major tributaries) by personnel in 4 government agencies to explore broad spatial and temporal patterns in benthic assemblages. We standardized sample size and taxonomy to account for differences in sampling, processing, and identification methods among agencies. Invertebrate assemblages were dominated by mayflies and caddisflies (46-83%). Percent Ephemeroptera, Plecoptera, Trichoptera (EPT) and standard diversity measures were inversely correlated, indicating that traditional macroinvertebrate Index of Biotic Integrity (IBI) approaches might not be applicable to large rivers. These data showed differences in assemblage composition across sub-basins and revealed effects of the spread of invasive Asian clams and of black fly management on benthic assemblage structure in the river. Large-river invertebrates are understudied and, even with challenges of combining data sets from multiple agencies, we showed the potential utility of applying data from a large river system to reveal ecological patterns across space and time.

Wilson, Matthew J.; McTammany, Matthew; Bilger, Michael D.; Reese, Sean; and Hayes, Benjamin R. “Combining Data from Multiple Agencies to Assess Benthic Macroinvertebrate Communities in a Large Gravel-Bed River.” Freshwater Science 34, no. 2 (2015) : 593-605.

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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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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

Chris Martine – Martine, Chris and Hale, Alison N. “Parasitism Disruption a Likely Consequence of Belowground War Waged by Exotic Plant Invader.” American Journal of Botany 102, no. 3 (2015) : 327-328.

Chris Martine, Associate Professor of Biology

Martine, Chris and Hale, Alison N. “Parasitism Disruption a Likely Consequence of Belowground War Waged by Exotic Plant Invader.” American Journal of Botany 102, no. 3 (2015) : 327-328.

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Friday, February 26th, 2016

Mark F. Haussmann – Lewin, Nora; Treidel, Lisa A.; Holekamp, Kay E.; Place, Ned J.; and Haussmann, Mark F. “Socioecological Variables Predict Telomere Length in Wild Spotted Hyenas.” Biology Letters 11, no. 2 (2015) : 20140991.

Mark F. Haussmann, Associate Professor of Biology

Telomeres are regarded as important biomarkers of ageing and serve as useful tools in revealing how stress acts at the cellular level. However, the effects of social and ecological factors on telomere length remain poorly understood, particularly in free-ranging mammals. Here, we investigated the influences of within-group dominance rank and group membership on telomere length in wild adult spotted hyenas (Crocuta crocuta). We found large effects of both factors; high-ranking hyenas exhibited significantly greater mean telomere length than did subordinate animals, and group membership significantly predicted mean telomere length within high-ranking females. We further inquired whether prey availability mediates the observed effect of group membership on telomere length, but this hypothesis was not supported. Interestingly, adult telomere length was not predicted by age. Our work shows for the first time, to the best of our knowledge, the effects of social rank on telomere length in a wild mammal and enhances our understanding of how social and ecological variables may contribute to organismal senescence.

Lewin, Nora; Treidel, Lisa A.; Holekamp, Kay E.; Place, Ned J.; and Haussmann, Mark F. “Socioecological Variables Predict Telomere Length in Wild Spotted Hyenas.” Biology Letters 11, no. 2 (2015) : 20140991.

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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

Chris Martine – Martine, Chris; Langdon, Stephen; Shearman, Timothy; Binggeli, Casey; and Mihuc, Timothy B. “European Frogbit (Hydrocharis morsus-ranae) in the Champlain/Adirondack Region: Recent Inferences.” Rhodora 117, no. 972 (2015) : 499-504.

Chris Martine, Associate Professor of Biology

As part of its north-south movement following introduction to Canada, Hydrocharis morsus-ranae L. (Hydrocharitaceae) has recently become established in slow-moving waters of the Champlain/Adirondack region of the northeastern US. The species is present on both the New York and Vermont shores of Lake Champlain and, so far, at a single location in the interior of the Adirondack Park. The southernmost Champlain/Adirondack occurrence is in the Champlain Canal south of Whitehall, NY (L. Eichler, Darrin Freshwater Institute, pers. comm.), within 25 miles of the Hudson River watershed—a population first recorded around 2006. Entry into the Hudson watershed, whether from the canal or Adirondack headwaters, has the potential to increase the spread of European frogbit well beyond the handful of spot occurrences currently recorded in the rest of the Northeast. The objective of this note is to summarize findings derived from recent student-driven research conducted on the status and biology of H. morsus-ranae in the Champlain/Adirondack region.

Martine, Chris; Langdon, Stephen; Shearman, Timothy; Binggeli, Casey; and Mihuc, Timothy B. “European Frogbit (Hydrocharis morsus-ranae) in the Champlain/Adirondack Region: Recent Inferences.” Rhodora 117, no. 972 (2015) : 499-504.

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Friday, February 26th, 2016

Mark F. Haussmann – Hau, Michaela; Haussmann, Mark F.; Greives, Timothy J.; Matlack, Christa; Costantini, David; Quetting, Michael; Adelman, James S.; Miranda, Ana Catarina; and Partecke, Jesko. “Repeated Stressors in Adulthood Increase the Rate of Biological Ageing.” Frontiers in Zoology 12, no. 4 (2015 ).

Mark F. Haussmann, Associate Professor of Biology

Background: Individuals of the same age can differ substantially in the degree to which they have accumulated tissue damage, akin to bodily wear and tear, from past experiences. This accumulated tissue damage reflects the individual’s biological age and may better predict physiological and behavioural performance than the individual’s chronological age. However, at present it remains unclear how to reliably assess biological age in individual wild vertebrates. Methods: We exposed hand-raised adult Eurasian blackbirds (Turdus merula) to a combination of repeated immune and disturbance stressors for over one year to determine the effects of chronic stress on potential biomarkers of biological ageing including telomere shortening, oxidative stress load, and glucocorticoid hormones. We also assessed general measures of individual condition including body mass and locomotor activity. Results: By the end of the experiment, stress-exposed birds showed greater decreases in telomere lengths. Stress-exposed birds also maintained higher circulating levels of oxidative damage compared with control birds. Other potential biomarkers such as concentrations of antioxidants and glucocorticoid hormone traits showed greater resilience and did not differ significantly between treatment groups. Conclusions: The current data demonstrate that repeated exposure to experimental stressors affects the rate of biological ageing in adult Eurasian blackbirds. Both telomeres and oxidative damage were affected by repeated stress exposure and thus can serve as blood-derived biomarkers of biological ageing.

Hau, Michaela; Haussmann, Mark F.; Greives, Timothy J.; Matlack, Christa; Costantini, David; Quetting, Michael; Adelman, James S.; Miranda, Ana Catarina; and Partecke, Jesko. “Repeated Stressors in Adulthood Increase the Rate of Biological Ageing.” Frontiers in Zoology 12, no. 4 (2015 ).

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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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