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Downs NC, Cresswell WJ, Reason P, Sutton G, Wells D, Wray S. Sex-Specific Habitat Preferences of Foraging and Commuting Lesser Horseshoe BatsRhinolophus hipposideros(Borkhausen, 1797) in Lowland England. ACTA CHIROPTEROLOGICA 2016. [DOI: 10.3161/15081109acc2016.18.2.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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McGuire L, Muise K, Shrivastav A, Willis C. No evidence of hyperphagia during prehibernation in a northern population of little brown bats (Myotis lucifugus). CAN J ZOOL 2016. [DOI: 10.1139/cjz-2016-0110] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
During autumn, temperate bats must deposit fat stores for hibernation. Populations at high latitudes face four challenges: a shorter active season and shorter nights during the active season (less time to accumulate fat), a longer hibernation period (larger fat store needed), and colder nights (reduced prey availability). Mating also occurs during the prehibernation period, placing time constraints for mating and fattening on northern populations. We tested the hypothesis that these factors constrain prehibernation foraging in northern populations of little brown bats (Myotis lucifugus (Le Conte, 1831)). We measured plasma triglyceride concentration to study prehibernation fueling rates of a population near the northern range limit of the species and compared our results with previously published results from a more southern population. In contrast to bats at the lower latitude, we found consistently low concentrations of plasma triglycerides, indicating a low fuelling rate throughout the prehibernation period. However, despite an apparently low fuelling rate, bats achieved a substantially greater body mass. The discrepancy between populations suggests that environmental constraints lead northern populations to employ different behavioural or physiological strategies to prepare for hibernation.
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Affiliation(s)
- L.P. McGuire
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
| | - K.A. Muise
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
| | - A. Shrivastav
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
| | - C.K.R. Willis
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
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Johnson JS, Treanor JJ, Lacki MJ, Baker MD, Falxa GA, Dodd LE, Waag AG, Lee EH. Migratory and winter activity of bats in Yellowstone National Park. J Mammal 2016. [DOI: 10.1093/jmammal/gyw175] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Postawa T, Nagy Z. Variation of parasitism patterns in bats during hibernation: the effect of host species, resources, health status, and hibernation period. Parasitol Res 2016; 115:3767-78. [PMID: 27240839 PMCID: PMC5040749 DOI: 10.1007/s00436-016-5138-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 05/17/2016] [Indexed: 02/01/2023]
Abstract
During critical periods of food shortage or variable climatic conditions, the choice of an appropriate host can increase the survival and reproductive performance of parasites. In turn, one of the unique adaptations to periodical food shortages is hibernation, which is often found among insectivorous bat species in the temperate zone. While hibernating, bats are completely defenseless against both predators and ectoparasites, their immune and endocrine systems are diminished, and survival is dependent on the accumulated fat reserves. Differences in the health status or in the rate of consumption of the resources might also explain species-specific differences in ectoparasite abundance, especially between closely related host species, such as the greater mouse-eared bat (Myotis myotis) and the lesser mouse-eared bat (M. blythii) during hibernation. In the present study, the abundance of two ecologically distinct (summer and winter) types of ectoparasites was examined in terms of its influence on the body condition and hemoglobin content of the two host species. The effects of demographic factors, such as host sex and age, were also investigated. Despite a similar pattern of deteriorating body condition and hemoglobin concentration, M. myotis was more parasitized than was M. blythii. The marked decrease in hemoglobin content in first-year females of both host species correlated with the highest parasite load and indicated a risk of anemia. At the intraspecific level, ectoparasite abundance was not correlated with body condition (resources), but it negatively affected hemoglobin content; however, this mostly concerned M. blythii, which had a lower parasite load. Therefore, it can be concluded that interspecific differences in ectoparasite abundance may result from parasites selecting the host species that is less sensitive to their activity. In turn, in summer ectoparasites, the preference for female hosts is probably attributable to the likelihood of reinfection rather than to an effect of host resources or health status. The absence of sex-based preferences in winter ectoparasites could be explained by equal host availability.
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Affiliation(s)
- Tomasz Postawa
- Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Sławkowska 17, 31-016, Kraków, Poland.
| | - Zoltan Nagy
- Foundation for School, Densusianu Str. 6/A, 400428, Cluj-Napoca, Romania
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Kohyt J, Rozik A, Kozakiewicz K, Pereswiet-Soltan A, Gubała WJ. Activity pattern and fat accumulation strategy of the Natterer’s bat (Vespertilionidae, Chiroptera) swarming population indicate the exact time of male mating effort. MAMMAL RES 2016. [DOI: 10.1007/s13364-016-0285-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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56
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Dalhoumi R, Aissa P, Aulagnier S. Seasonal variations of sexual size dimorphism in two Mediterranean bat species from Tunisia: the Kuhl's pipistrelle (Pipistrellus kuhlii) and the Isabelline serotine (Eptesicus isabellinus). FOLIA ZOOLOGICA 2016. [DOI: 10.25225/fozo.v65.i2.a11.2016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Ridha Dalhoumi
- Laboratoire de Biosurveillance de l'Environnement, Faculté des sciences de Bizerte, 7021 Zarzouna, Tunisie
| | - Patricia Aissa
- Laboratoire de Biosurveillance de l'Environnement, Faculté des sciences de Bizerte, 7021 Zarzouna, Tunisie
| | - Stéphane Aulagnier
- Comportement et Ecologie de la Faune Sauvage, I.N.R.A., B.P. 52627, 31326 Castanet Tolosan cedex, France
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Frank CL, Ingala MR, Ravenelle RE, Dougherty-Howard K, Wicks SO, Herzog C, Rudd RJ. The Effects of Cutaneous Fatty Acids on the Growth of Pseudogymnoascus destructans, the Etiological Agent of White-Nose Syndrome (WNS). PLoS One 2016; 11:e0153535. [PMID: 27070905 PMCID: PMC4829186 DOI: 10.1371/journal.pone.0153535] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 03/30/2016] [Indexed: 12/14/2022] Open
Abstract
White Nose Syndrome (WNS) greatly increases the over-winter mortality of little brown (Myotis lucifugus), Indiana (Myotis sodalis), northern (Myotis septentrionalis), and tricolored (Perimyotis subflavus) bats. It is caused by a cutaneous infection with the fungus Pseudogymnoascus destructans (Pd). Big brown bats (Eptesicus fuscus) are much more resistant to cutaneous infection with Pd, however. We thus conducted analyses of wing epidermis from hibernating E. fuscus and M. lucifugus to determine their fatty acid compositions, and laboratory Pd culture experiments at 4.0–13.4°C to determine the effects of these fatty acids on Pd growth. Our analyses revealed that the epidermis of both bat species contain the same 7 fatty acid types (14:0, 15:0, 16:0. 16:1, 18:0, 18:1, & 18:2), but the epidermis of M. lucifugus contains: a) more stearic (18:0) acid, b) less palmitoleic (16:1) acid, c) less myristic (14:0) acid, and, d) less oleic (18:1) acid than that of E. fuscus. The growth of Pd was inhibited by: a) myristic and stearic acids at 10.5–13.4°C, but not at 4.0–5.0°C, b) oleic acid at 5.0–10.6°C, c) palmitoleic acid, and, d) linoleic (18:2) acid at 5.0–10.6°C. One set of factors that enables E. fuscus to better resist cutaneous P. destructans infections (and thus WNS) therefore appears to be the relatively higher myristic, palmitoleic, and oleic acid contents of the epidermis.
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Affiliation(s)
- Craig L. Frank
- Department of Biological Sciences, Fordham University, Louis Calder Center, P.O. Box 887, Armonk, NY, 10504, United States of America
- * E-mail:
| | - Melissa R. Ingala
- Environmental Science Program, Fordham University, LH 400, Bronx, NY, 10458, United States of America
| | - Rebecca E. Ravenelle
- Department of Biological Sciences, Fordham University, Louis Calder Center, P.O. Box 887, Armonk, NY, 10504, United States of America
| | - Kelsey Dougherty-Howard
- Environmental Science Program, Fordham University, LH 400, Bronx, NY, 10458, United States of America
| | - Samuel O. Wicks
- Environmental Science Program, Fordham University, LH 400, Bronx, NY, 10458, United States of America
| | - Carl Herzog
- New York State Department of Environmental Conservation, 625 Broadway, Albany, NY, 12233, United States of America
| | - Robert J. Rudd
- New York State Department of Health, Wadsworth Center, Albany, NY, 12201, United States of America
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58
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Reynolds S, Kunz TH. Changes in body composition during reproduction and postnatal growth in the little brown bat,Myotis lucifugus(Chiroptera: Vespertilionidae). ECOSCIENCE 2016. [DOI: 10.1080/11956860.2000.11682565] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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59
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Abstract
Extended bouts of fasting are ingrained in the ecology of many organisms, characterizing aspects of reproduction, development, hibernation, estivation, migration, and infrequent feeding habits. The challenge of long fasting episodes is the need to maintain physiological homeostasis while relying solely on endogenous resources. To meet that challenge, animals utilize an integrated repertoire of behavioral, physiological, and biochemical responses that reduce metabolic rates, maintain tissue structure and function, and thus enhance survival. We have synthesized in this review the integrative physiological, morphological, and biochemical responses, and their stages, that characterize natural fasting bouts. Underlying the capacity to survive extended fasts are behaviors and mechanisms that reduce metabolic expenditure and shift the dependency to lipid utilization. Hormonal regulation and immune capacity are altered by fasting; hormones that trigger digestion, elevate metabolism, and support immune performance become depressed, whereas hormones that enhance the utilization of endogenous substrates are elevated. The negative energy budget that accompanies fasting leads to the loss of body mass as fat stores are depleted and tissues undergo atrophy (i.e., loss of mass). Absolute rates of body mass loss scale allometrically among vertebrates. Tissues and organs vary in the degree of atrophy and downregulation of function, depending on the degree to which they are used during the fast. Fasting affects the population dynamics and activities of the gut microbiota, an interplay that impacts the host's fasting biology. Fasting-induced gene expression programs underlie the broad spectrum of integrated physiological mechanisms responsible for an animal's ability to survive long episodes of natural fasting.
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Affiliation(s)
- Stephen M Secor
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, USA
| | - Hannah V Carey
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, Wisconsin, USA
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Vesterinen EJ, Ruokolainen L, Wahlberg N, Peña C, Roslin T, Laine VN, Vasko V, Sääksjärvi IE, Norrdahl K, Lilley TM. What you need is what you eat? Prey selection by the batMyotis daubentonii. Mol Ecol 2016; 25:1581-94. [DOI: 10.1111/mec.13564] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 01/08/2016] [Accepted: 01/26/2016] [Indexed: 12/24/2022]
Affiliation(s)
- Eero J. Vesterinen
- Department of Biology; University of Turku; Vesilinnantie 1 FI-20014 Turku Finland
- Spatial Foodweb Ecology Group; Department of Agricultural Sciences; University of Helsinki; Latokartanonkaari 5 FI-00014 Helsinki Finland
| | - Lasse Ruokolainen
- Department of Biosciences; University of Helsinki; Viikinkaari 1 FI-00014 Helsinki Finland
| | - Niklas Wahlberg
- Department of Biology; University of Turku; Vesilinnantie 1 FI-20014 Turku Finland
- Department of Biology; Lund University; Sölvegatan 35 223 62 Lund Sweden
| | - Carlos Peña
- Department of Biology; University of Turku; Vesilinnantie 1 FI-20014 Turku Finland
| | - Tomas Roslin
- Spatial Foodweb Ecology Group; Department of Agricultural Sciences; University of Helsinki; Latokartanonkaari 5 FI-00014 Helsinki Finland
- Department of Ecology; Swedish University of Agricultural Sciences; Box 7044 750 07 Uppsala Sweden
| | - Veronika N. Laine
- Department of Animal Ecology; Netherlands Institute of Ecology (NIOO-KNAW); PO Box 50 6700AB Wageningen The Netherlands
| | - Ville Vasko
- Department of Biology; University of Turku; Vesilinnantie 1 FI-20014 Turku Finland
| | - Ilari E. Sääksjärvi
- Department of Biology; University of Turku; Vesilinnantie 1 FI-20014 Turku Finland
| | - Kai Norrdahl
- Department of Biology; University of Turku; Vesilinnantie 1 FI-20014 Turku Finland
| | - Thomas M. Lilley
- Department of Biology; University of Turku; Vesilinnantie 1 FI-20014 Turku Finland
- Biology Department; Bucknell University; 1 Dent Drive Lewisburg PA 17837 USA
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61
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Powers KE, Reynolds RJ, Orndorff W, Hyzy BA, Hobson CS, Ford WM. Monitoring the Status of Gray Bats (Myotis grisescens) in Virginia, 2009–2014, and Potential Impacts of White-Nose Syndrome. SOUTHEAST NAT 2016. [DOI: 10.1656/058.015.0114] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Hayman DTS, Pulliam JRC, Marshall JC, Cryan PM, Webb CT. Environment, host, and fungal traits predict continental-scale white-nose syndrome in bats. SCIENCE ADVANCES 2016; 2:e1500831. [PMID: 27152322 PMCID: PMC4846429 DOI: 10.1126/sciadv.1500831] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 11/30/2015] [Indexed: 06/05/2023]
Abstract
White-nose syndrome is a fungal disease killing bats in eastern North America, but disease is not seen in European bats and is less severe in some North American species. We show that how bats use energy during hibernation and fungal growth rates under different environmental conditions can explain how some bats are able to survive winter with infection and others are not. Our study shows how simple but nonlinear interactions between fungal growth and bat energetics result in decreased survival times at more humid hibernation sites; however, differences between species such as body size and metabolic rates determine the impact of fungal infection on bat survival, allowing European bat species to survive, whereas North American species can experience dramatic decline.
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Affiliation(s)
- David T. S. Hayman
- Molecular Epidemiology and Public Health Laboratory, Hopkirk Research Institute, Massey University, Private Bag, 11 222, Palmerston North 4442, New Zealand
| | - Juliet R. C. Pulliam
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
- Emerging Pathogens Institute, University of Florida, Gainesville, FL 32611, USA
- Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jonathan C. Marshall
- Molecular Epidemiology and Public Health Laboratory, Hopkirk Research Institute, Massey University, Private Bag, 11 222, Palmerston North 4442, New Zealand
- Institute of Fundamental Sciences, Massey University, Private Bag, 11 222, Palmerston North 4442, New Zealand
| | - Paul M. Cryan
- U.S. Geological Survey, Fort Collins Science Center, Fort Collins, CO 80526, USA
| | - Colleen T. Webb
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
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63
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Burns LE, Broders HG. Maximizing mating opportunities: higher autumn swarming activity in male versus femaleMyotisbats. J Mammal 2015. [DOI: 10.1093/jmammal/gyv141] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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64
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Temporal Changes in Body Mass and Body Condition of Cave-Hibernating Bats During Staging and Swarming. JOURNAL OF FISH AND WILDLIFE MANAGEMENT 2015. [DOI: 10.3996/042015-jfwm-033] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abstract
The rapid colonization of the Pseudogymnoascus destructans fungus across cave systems in eastern North America and the associated bat mortalities (white-nose syndrome; WNS), necessitates studies of cave-hibernating bats that remain unaffected by, or in close proximity to, the leading edge of the fungal distribution to provide baseline predisturbance data from which to assess changes due to fungal effects. Studies of the physiological ecology of cave-hibernating bats during the spring staging and autumn swarming seasons are few, and an understanding of patterns in body condition of bats associated with entry into and emergence from hibernation is incomplete. We sampled bats at the entrance to a cave in Mammoth Cave National Park, Kentucky, during swarming and staging, prior to (2011 and 2012), concurrent with (2013), and following (2014) the arrival of the WNS fungus. We evaluated seasonal and annual changes in body mass and body condition of bats entering and leaving the cave. We captured 1,232 bats of eight species. Sex ratios of all species were male-biased. Capture success was substantially reduced in 2014, following the second winter after arrival of the WNS fungus. Significant temporal variation in body mass and body mass index was observed for little brown bats Myotis lucifugus, northern long-eared bats M. septentrionalis, and tri-colored bats Perimyotis subflavus, but not Indiana bats M. sodalis. Little brown bats and northern long-eared bats demonstrated significant increases in mean body mass index in 2014; this pattern likely reflected a relatively better body condition in bats that survived exposure to the WNS fungus. Most species demonstrated highest body mass and body mass index values in late swarming compared with other sampling periods, with tri-colored bats showing the greatest percent increase in body mass (42.5%) and body mass index (42.9%) prior to entering hibernation. These data indicate significant intraspecific variation in body condition of cave-hibernating bat species, both among years and between the seasons of autumn swarming and spring staging. We suggest this variation is likely to have implications for the relative vulnerability of species to WNS infection across the distribution of the Pseudogymnoascus fungus.
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65
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Gallant A, Broders H. Body condition explains little of the interindividual variation in the swarming behaviour of adult male little brown myotis ( Myotis lucifugus) in Nova Scotia, Canada. CAN J ZOOL 2015. [DOI: 10.1139/cjz-2014-0249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two competing activities of temperate insectivorous bats during the fall swarming period have direct fitness consequences: fat storage for hibernation and mating. This study investigated whether interindividual variation in body condition (as a metric of stored fat; body mass/forearm length) correlated with reproductive status and influenced swarming behaviour of adult male little brown myotis (Myotis lucifugus (Le Conte, 1831)) in Nova Scotia, Canada. We predicted that bats in good body condition would more likely be reproductive and would be more likely to remain at, and closer to, a swarming site than males in poor body condition. As predicted, males in good body condition were more likely to be in advanced reproductive states than those in poor body condition. However, contrary to the prediction, males in good body condition spent significantly less time at the swarming site than males with poor body condition. There was no difference between bats of contrasting body conditions in the probability of relocating them or how far from the swarming site they roosted. Because variation in swarming behaviours of male M. lucifugus at a swarming site was not explained by body condition, one or more other factors (e.g., social, energetic) must be important.
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Affiliation(s)
- A.J. Gallant
- Department of Biology, St. Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
- Department of Biology, St. Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
| | - H.G. Broders
- Department of Biology, St. Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
- Department of Biology, St. Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
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67
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Karen EP, Richard JR, Wil O, W MF, Christopher SH. Post-White-nose syndrome trends in Virginias cave bats, 2008-2013. ACTA ACUST UNITED AC 2015. [DOI: 10.5897/jene2015.0507] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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68
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Burns LE, Broders HG. Who swarms with whom? Group dynamics of Myotis bats during autumn swarming. Behav Ecol 2015. [DOI: 10.1093/beheco/arv017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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69
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Grieneisen LE, Brownlee-Bouboulis SA, Johnson JS, Reeder DM. Sex and hibernaculum temperature predict survivorship in white-nose syndrome affected little brown myotis (Myotis lucifugus). ROYAL SOCIETY OPEN SCIENCE 2015; 2:140470. [PMID: 26064604 PMCID: PMC4448800 DOI: 10.1098/rsos.140470] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 01/08/2015] [Indexed: 05/14/2023]
Abstract
White-nose syndrome (WNS), an emerging infectious disease caused by the novel fungus Pseudogymnoascus 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.
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70
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Langwig KE, Frick WF, Reynolds R, Parise KL, Drees KP, Hoyt JR, Cheng TL, Kunz TH, Foster JT, Kilpatrick AM. Host and pathogen ecology drive the seasonal dynamics of a fungal disease, white-nose syndrome. Proc Biol Sci 2015; 282:20142335. [PMID: 25473016 PMCID: PMC4286034 DOI: 10.1098/rspb.2014.2335] [Citation(s) in RCA: 141] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Accepted: 11/06/2014] [Indexed: 01/16/2023] Open
Abstract
Seasonal patterns in pathogen transmission can influence the impact of disease on populations and the speed of spatial spread. Increases in host contact rates or births drive seasonal epidemics in some systems, but other factors may occasionally override these influences. White-nose syndrome, caused by the emerging fungal pathogen Pseudogymnoascus destructans, is spreading across North America and threatens several bat species with extinction. We examined patterns and drivers of seasonal transmission of P. destructans by measuring infection prevalence and pathogen loads in six bat species at 30 sites across the eastern United States. Bats became transiently infected in autumn, and transmission spiked in early winter when bats began hibernating. Nearly all bats in six species became infected by late winter when infection intensity peaked. In summer, despite high contact rates and a birth pulse, most bats cleared infections and prevalence dropped to zero. These data suggest the dominant driver of seasonal transmission dynamics was a change in host physiology, specifically hibernation. Our study is the first, to the best of our knowledge, to describe the seasonality of transmission in this emerging wildlife disease. The timing of infection and fungal growth resulted in maximal population impacts, but only moderate rates of spatial spread.
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Affiliation(s)
- Kate E Langwig
- Department of Ecology and Evolutionary Biology, University of California, EE Biology/EMS, Santa Cruz, CA 95064, USA
| | - Winifred F Frick
- Department of Ecology and Evolutionary Biology, University of California, EE Biology/EMS, Santa Cruz, CA 95064, USA
| | - Rick Reynolds
- Virginia Department of Game and Inland Fisheries, 517 Lee Highway, Verona, VA 24482, USA
| | - Katy L Parise
- Department of Biology, Boston University, Boston, MA 02215, USA
| | - Kevin P Drees
- Department of Biology, Boston University, Boston, MA 02215, USA
| | - Joseph R Hoyt
- Department of Ecology and Evolutionary Biology, University of California, EE Biology/EMS, Santa Cruz, CA 95064, USA
| | - Tina L Cheng
- Department of Ecology and Evolutionary Biology, University of California, EE Biology/EMS, Santa Cruz, CA 95064, USA
| | - Thomas H Kunz
- Department of Biology, Boston University, Boston, MA 02215, USA
| | - Jeffrey T Foster
- Center for Microbial Genetics and Genomics, Northern Arizona University, Flagstaff, AZ 86011-4073, USA Department of Molecular, Cellular and Biomedical Science, University of New Hampshire, Durham, NH 03824, USA
| | - A Marm Kilpatrick
- Department of Ecology and Evolutionary Biology, University of California, EE Biology/EMS, Santa Cruz, CA 95064, USA
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Budinski I, Jojić V, Jovanović VM, Bjelić-Čabrilo O, Paunović M, Vujošević M. Cranial variation of the greater horseshoe bat Rhinolophus ferrumequinum (Chiroptera: Rhinolophidae) from the central Balkans. ZOOL ANZ 2015. [DOI: 10.1016/j.jcz.2014.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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72
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Wu CW, Biggar KK, Storey KB. Expression profiling and structural characterization of microRNAs in adipose tissues of hibernating ground squirrels. GENOMICS PROTEOMICS & BIOINFORMATICS 2014; 12:284-91. [PMID: 25526980 PMCID: PMC4411486 DOI: 10.1016/j.gpb.2014.08.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 07/24/2014] [Accepted: 08/17/2014] [Indexed: 12/05/2022]
Abstract
MicroRNAs (miRNAs) are small non-coding RNAs that are important in regulating metabolic stress. In this study, we determined the expression and structural characteristics of 20 miRNAs in brown (BAT) and white adipose tissue (WAT) during torpor in thirteen-lined ground squirrels. Using a modified stem-loop technique, we found that during torpor, expression of six miRNAs including let-7a, let-7b, miR-107, miR-150, miR-222 and miR-31 was significantly downregulated in WAT (P < 0.05), which was 16%–54% of euthermic non-torpid control squirrels, whereas expression of three miRNAs including miR-143, miR-200a and miR-519d was found to be upregulated by 1.32–2.34-fold. Similarly, expression of more miRNAs was downregulated in BAT during torpor. We detected reduced expression of 6 miRNAs including miR-103a, miR-107, miR-125b, miR-21, miR-221 and miR-31 (48%–70% of control), while only expression of miR-138 was significantly upregulated (2.91 ± 0.8-fold of the control, P < 0.05). Interestingly, miRNAs found to be downregulated in WAT during torpor were similar to those dysregulated in obese humans for increased adipogenesis, whereas miRNAs with altered expression in BAT during torpor were linked to mitochondrial β-oxidation. miRPath target prediction analysis showed that miRNAs downregulated in both WAT and BAT were associated with the regulation of mitogen-activated protein kinase (MAPK) signaling, while the miRNAs upregulated in WAT were linked to transforming growth factor β (TGFβ) signaling. Compared to mouse sequences, no unique nucleotide substitutions within the stem-loop region were discovered for the associated pre-miRNAs for the miRNAs used in this study, suggesting no structure-influenced changes in pre-miRNA processing efficiency in the squirrel. As well, the expression of miRNA processing enzyme Dicer remained unchanged in both tissues during torpor. Overall, our findings suggest that changes of miRNA expression in adipose tissues may be linked to distinct biological roles in WAT and BAT during hibernation and may involve the regulation of signaling cascades.
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Affiliation(s)
- Cheng-Wei Wu
- Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Kyle K Biggar
- Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Kenneth B Storey
- Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada.
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73
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Frank CL, Michalski A, McDonough AA, Rahimian M, Rudd RJ, Herzog C. The resistance of a North American bat species (Eptesicus fuscus) to White-nose Syndrome (WNS). PLoS One 2014; 9:e113958. [PMID: 25437448 PMCID: PMC4250063 DOI: 10.1371/journal.pone.0113958] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 10/31/2014] [Indexed: 01/19/2023] Open
Abstract
White-nose Syndrome (WNS) is the primary cause of over-winter mortality for little brown (Myotis lucifugus), northern (Myotis septentrionalis), and tricolored (Perimyotis subflavus) bats, and is due to cutaneous infection with the fungus Pseudogymnoascus (Geomyces) destructans (Pd). Cutaneous infection with P. destructans disrupts torpor patterns, which is thought to lead to a premature depletion of body fat reserve. Field studies were conducted at 3 WNS-affected hibernation sites to determine if big brown bats (Eptesicus fuscus) are resistant to Pd. Radio telemetry studies were conducted during 2 winters to determine the torpor patterns of 23 free-ranging E. fuscus hibernating at a site where Pd occurs. The body fat contents of free-ranging E. fuscus and M. lucifugus during hibernation at 2 different WNS-affected sites were also determined. The numbers of bats hibernating at the same site was determined during both: a) 4–7 years prior to the arrival of Pd, and, b) 2–3 years after it first appeared at this site. The torpor bouts of big brown bats hibernating at a WNS-affected site were not significantly different in length from those previously reported for this species. The mean body fat content of E. fuscus in February was nearly twice that of M. lucifugus hibernating at the same WNS-affected sites during this month. The number of M. lucifugus hibernating at one site decreased by 99.6% after P. destructans first appeared, whereas the number of E. fuscus hibernating there actually increased by 43% during the same period. None of the E. fuscus collected during this study had any visible fungal growth or lesions on their skin, whereas virtually all the M. lucifugus collected had visible fungal growth on their wings, muzzle, and ears. These findings indicate that big brown bats are resistant to WNS.
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Affiliation(s)
- Craig L. Frank
- Department of Biological Sciences, Fordham University, Louis Calder Center, P.O. Box 887, Armonk, NY 10504, United States of America
- * E-mail:
| | - Andrew Michalski
- Environmental Science Program, Fordham University, LH 400, Bronx, NY 10458, United States of America
| | - Anne A. McDonough
- Department of Biological Sciences, Fordham University, Louis Calder Center, P.O. Box 887, Armonk, NY 10504, United States of America
| | - Marjon Rahimian
- Department of Biological Sciences, Fordham University, Louis Calder Center, P.O. Box 887, Armonk, NY 10504, United States of America
| | - Robert J. Rudd
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States of America
| | - Carl Herzog
- New York State Department of Environmental Conservation, 625 Broadway, Albany, NY 12233, United States of America
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74
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Johnson JS, Reeder DM, McMichael JW, Meierhofer MB, Stern DWF, Lumadue SS, Sigler LE, Winters HD, Vodzak ME, Kurta A, Kath JA, Field KA. Host, pathogen, and environmental characteristics predict white-nose syndrome mortality in captive little brown myotis (Myotis lucifugus). PLoS One 2014; 9:e112502. [PMID: 25409028 PMCID: PMC4237369 DOI: 10.1371/journal.pone.0112502] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 10/15/2014] [Indexed: 01/22/2023] Open
Abstract
An estimated 5.7 million or more bats died in North America between 2006 and 2012 due to infection with the fungus Pseudogymnoascus destructans (Pd) that causes white-nose syndrome (WNS) during hibernation. The behavioral and physiological changes associated with hibernation leave bats vulnerable to WNS, but the persistence of bats within the contaminated regions of North America suggests that survival might vary predictably among individuals or in relation to environmental conditions. To investigate variables influencing WNS mortality, we conducted a captive study of 147 little brown myotis (Myotis lucifugus) inoculated with 0, 500, 5 000, 50 000, or 500 000 Pd conidia and hibernated for five months at either 4 or 10°C. We found that female bats were significantly more likely to survive hibernation, as were bats hibernated at 4°C, and bats with greater body condition at the start of hibernation. Although all bats inoculated with Pd exhibited shorter torpor bouts compared to controls, a characteristic of WNS, only bats inoculated with 500 conidia had significantly lower survival odds compared to controls. These data show that host and environmental characteristics are significant predictors of WNS mortality, and that exposure to up to 500 conidia is sufficient to cause a fatal infection. These results also illustrate a need to quantify dynamics of Pd exposure in free-ranging bats, as dynamics of WNS produced in captive studies inoculating bats with several hundred thousand conidia may differ from those in the wild.
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Affiliation(s)
- Joseph S. Johnson
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
| | - DeeAnn M. Reeder
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
| | - James W. McMichael
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
| | - Melissa B. Meierhofer
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
| | - Daniel W. F. Stern
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
| | - Shayne S. Lumadue
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
| | - Lauren E. Sigler
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
| | - Harrison D. Winters
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
| | - Megan E. Vodzak
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
| | - Allen Kurta
- Department of Biology, Eastern Michigan University, Ypsilanti, Michigan, United States of America
| | - Joseph A. Kath
- Illinois Department of Natural Resources, Springfield, Illinois, United States of America
| | - Kenneth A. Field
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, United States of America
- * E-mail:
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75
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Burns LE, Frasier TR, Broders HG. Genetic connectivity among swarming sites in the wide ranging and recently declining little brown bat (Myotis lucifugus). Ecol Evol 2014; 4:4130-49. [PMID: 25505539 PMCID: PMC4242565 DOI: 10.1002/ece3.1266] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 08/29/2014] [Accepted: 09/03/2014] [Indexed: 01/29/2023] Open
Abstract
Characterizing movement dynamics and spatial aspects of gene flow within a species permits inference on population structuring. As patterns of structuring are products of historical and current demographics and gene flow, assessment of structure through time can yield an understanding of evolutionary dynamics acting on populations that are necessary to inform management. Recent dramatic population declines in hibernating bats in eastern North America from white-nose syndrome have prompted the need for information on movement dynamics for multiple bat species. We characterized population genetic structure of the little brown bat, Myotis lucifugus, at swarming sites in southeastern Canada using 9 nuclear microsatellites and a 292-bp region of the mitochondrial genome. Analyses of F ST, ΦST, and Bayesian clustering (STRUCTURE) found weak levels of genetic structure among swarming sites for the nuclear and mitochondrial genome (Global F ST = 0.001, P < 0.05, Global ΦST = 0.045, P < 0.01, STRUCTURE K = 1) suggesting high contemporary gene flow. Hierarchical AMOVA also suggests little structuring at a regional (provincial) level. Metrics of nuclear genetic structure were not found to differ between males and females suggesting weak asymmetries in gene flow between the sexes. However, a greater degree of mitochondrial structuring does support male-biased dispersal long term. Demographic analyses were consistent with past population growth and suggest a population expansion occurred from approximately 1250 to 12,500 BP, following Pleistocene deglaciation in the region. Our study suggests high gene flow and thus a high degree of connectivity among bats that visit swarming sites whereby mainland areas of the region may be best considered as one large gene pool for management and conservation.
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Affiliation(s)
- Lynne E Burns
- Department of Biology, Dalhousie University, Life Sciences Centre 1355 Oxford Street, Halifax, Nova Scotia, B3H 4J1, Canada
| | - Timothy R Frasier
- Department of Biology, Saint Mary's University 923 Robie Street, Halifax, Nova Scotia, B3H 3C3, Canada
| | - Hugh G Broders
- Department of Biology, Saint Mary's University 923 Robie Street, Halifax, Nova Scotia, B3H 3C3, Canada
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76
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Morals DB, Barros MS, Freitas MBD, Da Matta SLP. Seasonal assessment of the reproductive cycle and energy reserves of male batsSturnira lilium(Chiroptera: Phyllostomidae). J Mammal 2014. [DOI: 10.1644/14-mamm-a-080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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77
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Vasilieva N, Tchabovsky A. Timing is the only thing: reproduction in female yellow ground squirrels (Spermophilus fulvus). CAN J ZOOL 2014. [DOI: 10.1139/cjz-2014-0084] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Based on 4-year field observations of yellow ground squirrels (Spermophilus fulvus (Lichtenstein, 1823)), we determined whether female reproductive effort, annual reproductive success, and survival were dependent on age, body condition, time of emergence from hibernation, and previous reproduction. The probability of weaning a litter did not vary with female age, body condition, time of emergence, or previous reproduction. Litter size, litter mass, and offspring survival did not vary with age, whereas individual offspring mass was lower in yearlings than in older females. Body condition upon emergence had no effect on litter size, litter mass, offspring mass, and survival. Reproduction did not influence female survival, physical condition upon emergence next spring, or subsequent reproductive efforts. The only factor that affected the extent of reproductive effort and offspring survival was the date of emergence: the later a female emerged, the lower the total and mean offspring mass, and fewer offspring survived. The modulation of reproduction in female S. fulvus by only the timing of vernal emergence and independent of other individual characteristics can be explained by the high costs of missed reproductive opportunity because of short longevity combined with low costs of reproduction when resources are abundant enough to meet both somatic and reproductive needs.
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Affiliation(s)
- N.A. Vasilieva
- A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, 33, Leninskii pr., Moscow, 119071, Russia
| | - A.V. Tchabovsky
- A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, 33, Leninskii pr., Moscow, 119071, Russia
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78
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Affiliation(s)
- K. J. O. Norquay
- Department of Biology and Centre for Forest Interdisciplinary Research; University of Winnipeg; Winnipeg MB Canada
| | - C. K. R. Willis
- Department of Biology and Centre for Forest Interdisciplinary Research; University of Winnipeg; Winnipeg MB Canada
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79
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Rughetti M, Toffoli R. Sex-Specific Seasonal Change in Body Mass in Two Species of Vespertilionid Bats. ACTA CHIROPTEROLOGICA 2014. [DOI: 10.3161/150811014x683363] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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80
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Histomorphometric characterization of the intertubular compartment in the testes of the bat Sturnira lilium. Anim Reprod Sci 2014; 147:180-6. [DOI: 10.1016/j.anireprosci.2014.03.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 03/03/2014] [Accepted: 03/07/2014] [Indexed: 11/18/2022]
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81
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Speakman JR. Evolutionary perspectives on the obesity epidemic: adaptive, maladaptive, and neutral viewpoints. Annu Rev Nutr 2014; 33:289-317. [PMID: 23862645 DOI: 10.1146/annurev-nutr-071811-150711] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The prevalence of obesity in modern societies has two major contributory factors-an environmental change that has happened in historical times and a genetic predisposition that has its origins in our evolutionary history. Understanding both aspects is complex. From an evolutionary perspective, three different types of explanation have been proposed. The first is that obesity was once adaptive and enabled us to survive (or sustain fecundity) through periods of famine. People carrying so-called thrifty genes that enabled the efficient storage of energy as fat between famines would be at a selective advantage. In the modern world, however, people who have inherited these genes deposit fat in preparation for a famine that never comes, and the result is widespread obesity. The key problem with this, and any other adaptive scenario, is to understand why, if obesity was historically so advantageous, many people did not inherit these thrifty genes and in modern society are able to remain slim, despite the environmental change favoring fat storage. The second type of explanation is that obesity is not adaptive and may never even have existed in our evolutionary past, but it is favored today as a maladaptive by-product of positive selection on some other trait. An example of this type of explanation is the suggestion that obesity results from variation in brown adipose tissue thermogenesis. Finally, a third class of explanation is that most mutations in the genes that predispose us to obesity are neutral and have been drifting over evolutionary time--so-called drifty genes, leading some individuals to be obesity prone and others obesity resistant. In this article, I review the current evidence for and against these three different scenarios and conclude that the thrifty gene hypothesis is untenable but the other two ideas may provide a cogent explanation of the modern obesity phenomenon.
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Affiliation(s)
- John R Speakman
- Key State Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang, Beijing 100101, People's Republic of China.
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82
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Day KM, Tomasi TE. Winter energetics of female Indiana bats Myotis sodalis. Physiol Biochem Zool 2014; 87:56-64. [PMID: 24457921 DOI: 10.1086/671563] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Understanding physiological limits and environmental optima is critical to developing protection strategies for endangered and threatened species. One theory to explain the decline in endangered Indiana bat Myotis sodalis populations involves increasing cave temperatures in winter hibernacula. Altered cave temperatures can raise metabolism and cause more arousals in torpid bats, both of which use more fat reserves. In addition, fluctuations in cave temperatures may cause additional arousals. Our objectives were to quantify the effect of temperature and fluctuations thereof on torpid metabolism and arousal frequency in this species. Female Indiana bats (n=36) were collected from caves just before hibernation, maintained in an environmental chamber that simulated hibernacula conditions, and had skin temperature recorded every 30 min throughout the winter. One environmental chamber containing bats (n=12) was sequentially set at 8°, 6°, and 4°C over the winter. The second chamber containing bats (n=12) experienced the same mean temperatures, but temperature fluctuated ±2°C on a regular basis. Torpor bouts were longest at 4°C and were not affected by temperature fluctuations. However, the temperature fluctuations appeared to cause longer arousals. Other bats (n=12) were individually placed in metabolic chambers to calculate oxygen consumption during torpor and during arousals. Torpid metabolism was affected by temperature; at 9°C, it was higher than at 7° or 5°C. Metabolism during arousals was not different among temperature treatments, but rates were almost 200 times higher than torpid metabolic rates. We calculated a winter energy budget and, from the energetic perspective, determined an optimum hibernation temperature (3°-6°C) for female Indiana bats. These findings suggest that hibernacula that provide these conditions deserve extra protection, although other factors in addition to energetics may play a role in temperature preferences.
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Affiliation(s)
- Katie M Day
- Department of Biology, Missouri State University, Springfield, Missouri 65897
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83
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Affiliation(s)
- C. Stawski
- Institute of Environmental Sciences; Jagiellonian University; Kraków Poland
- Centre for Behavioural and Physiological Ecology, Zoology; University of New England; Armidale NSW Australia
| | - C. K. R. Willis
- Department of Biology and Centre for Forest Interdisciplinary Research; University of Winnipeg; Winnipeg Canada
| | - F. Geiser
- Centre for Behavioural and Physiological Ecology, Zoology; University of New England; Armidale NSW Australia
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84
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Noonan MJ, Markham A, Newman C, Trigoni N, Buesching CD, Ellwood SA, Macdonald DW. Climate and the individual: inter-annual variation in the autumnal activity of the European badger (Meles meles). PLoS One 2014; 9:e83156. [PMID: 24465376 PMCID: PMC3894934 DOI: 10.1371/journal.pone.0083156] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Accepted: 10/30/2013] [Indexed: 11/23/2022] Open
Abstract
We establish intra-individual and inter-annual variability in European badger (Meles meles) autumnal nightly activity in relation to fine-scale climatic variables, using tri-axial accelerometry. This contributes further to understanding of causality in the established interaction between weather conditions and population dynamics in this species. Modelling found that measures of daylight, rain/humidity, and soil temperature were the most supported predictors of ACTIVITY, in both years studied. In 2010, the drier year, the most supported model included the SOLAR*RH interaction, RAIN, and30cmTEMP (w = 0.557), while in 2012, a wetter year, the most supported model included the SOLAR*RH interaction, and the RAIN*10cmTEMP (w = 0.999). ACTIVITY also differed significantly between individuals. In the 2012 autumn study period, badgers with the longest per noctem activity subsequently exhibited higher Body Condition Indices (BCI) when recaptured. In contrast, under drier 2010 conditions, badgers in good BCI engaged in less per noctem activity, while badgers with poor BCI were the most active. When compared on the same calendar dates, to control for night length, duration of mean badger nightly activity was longer (9.5 hrs ±3.3 SE) in 2010 than in 2012 (8.3 hrs ±1.9 SE). In the wetter year, increasing nightly activity was associated with net-positive energetic gains (from BCI), likely due to better foraging conditions. In a drier year, with greater potential for net-negative energy returns, individual nutritional state proved crucial in modifying activity regimes; thus we emphasise how a ‘one size fits all’ approach should not be applied to ecological responses.
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Affiliation(s)
- Michael J. Noonan
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Tubney, Oxfordshire, United Kingdom
| | - Andrew Markham
- Department of Computer Science, University of Oxford, Wolfson Building, Oxfordshire, United Kingdom
| | - Chris Newman
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Tubney, Oxfordshire, United Kingdom
| | - Niki Trigoni
- Department of Computer Science, University of Oxford, Wolfson Building, Oxfordshire, United Kingdom
| | - Christina D. Buesching
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Tubney, Oxfordshire, United Kingdom
| | - Stephen A. Ellwood
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Tubney, Oxfordshire, United Kingdom
| | - David W. Macdonald
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Tubney, Oxfordshire, United Kingdom
- * E-mail:
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85
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Barros MS, Morais DB, Araújo MR, Carvalho TF, Matta SLP, Pinheiro EC, Freitas MB. Seasonal variation of energy reserves and reproduction in neotropical free-tailed bats Molossus molossus (Chiroptera: Molossidae). BRAZ J BIOL 2013; 73:629-35. [DOI: 10.1590/s1519-69842013000300022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Accepted: 08/30/2012] [Indexed: 11/22/2022] Open
Abstract
Seasonal variation is a key factor regulating energy metabolism and reproduction in several mammals, including bats. This study aimed to track seasonal changes in the energy reserves of the insectivorous bat Molossus molossus associated with its reproductive cycle. Adult males were collected during the four neotropical annual seasons in Viçosa - MG, Brazil. Blood and tissues were collected for metabolic analysis and testes were removed for histology and morphometry. Our results show that liver and breast muscle glycogen concentrations were significantly lower in winter. The adiposity index was significantly higher in the fall compared to winter and spring. Seminiferous tubules were greater in diameter in animals captured in fall and winter, indicating a higher investment in spermatic production during these seasons. The percentage of Leydig cells was higher in summer compared to fall and winter. We suggest that M. molossus presents a type of seasonal reproduction with two peaks of testicular activity: one in fall, with higher sperm production (spermatogenesis), and another in summer, with higher hormone production (steroidogenesis). The metabolic pattern may be associated with reproductive events, especially due to the highest fat storage observed in the fall, which coincides with the further development of the seminiferous tubules.
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Affiliation(s)
| | - DB. Morais
- Federal University of Viçosa, Viçosa, Brazil
| | - MR. Araújo
- Federal University of Viçosa, Viçosa, Brazil
| | | | - SLP. Matta
- Federal University of Viçosa, Viçosa, Brazil
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86
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Ehlman SM, Cox JJ, Crowley PH. Evaporative water loss, spatial distributions, and survival in white-nose-syndrome-affected little brown myotis: a model. J Mammal 2013. [DOI: 10.1644/12-mamm-a-111.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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87
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Norquay KJO, Martinez-Nuñez F, Dubois JE, Monson KM, Willis CKR. Long-distance movements of little brown bats (Myotis lucifugus). J Mammal 2013. [DOI: 10.1644/12-mamm-a-065.1] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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88
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McGuire LP, Fenton MB, Guglielmo CG. Phenotypic flexibility in migrating bats: seasonal variation in body composition, organ sizes and fatty acid profiles. J Exp Biol 2013; 216:800-8. [DOI: 10.1242/jeb.072868] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Many species of bats migrate long distances, but the physiological challenges of migration are poorly understood. We tested the hypothesis that migration is physiologically demanding for bats by examining migration-related phenotypic flexibility. Both bats and birds are endothermic, flying vertebrates; therefore, we predicted that migration would result in similar physiological trade-offs. We compared hoary bats (Lasiurus cinereus) during spring migration and summer non-migratory periods, comparing our results with previous observations of birds. Migrating bats had reduced digestive organs, enlarged exercise organs, and fat stores had higher proportions of polyunsaturated fatty acids (PUFAs). These results are consistent with previous studies of migrating birds; however, we also found sex differences not typically associated with bird migration. Migrating female hoary bats increased the relative size of fat stores by reducing lean body components, while males maintained the same relative amount of fat in both seasons. The ratio of n-6 to n-3 PUFA in flight muscle membrane increased in migrating males and decreased in migrating females, consistent with males using torpor more frequently than females during spring migration. Enlarged exercise organs, reduced digestive organs and changes in adipose tissue composition reflect the elevated energetic demands of migration. Sex-specific patterns of fat storage and muscle membrane composition likely reflect challenges faced by females that migrate while pregnant. Our results provide some of the first insights into the physiological demands of bat migration and highlight key differences between bats and birds.
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Affiliation(s)
- Liam P. McGuire
- Department of Biology, University of Western Ontario, 1151 Richmond Street N., London, Ontario, Canada, N6A 5B7
| | - M. Brock Fenton
- Department of Biology, University of Western Ontario, 1151 Richmond Street N., London, Ontario, Canada, N6A 5B7
| | - Christopher G. Guglielmo
- Department of Biology, University of Western Ontario, 1151 Richmond Street N., London, Ontario, Canada, N6A 5B7
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89
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Bordignon MO, França ADO. Reproduction of the greater bulldog bat Noctilio leporinus (Chiroptera: Noctilionidae) in a mangrove area in southern Brazil. BIOTA NEOTROPICA 2012. [DOI: 10.1590/s1676-06032012000400006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reproductive pattern of the greater bulldog bat (Noctilio leporinus) was studied in southern Brazil from January to December 1999. The morphological characteristics of their reproductive organs were recorded monthly, through histological analysis of testes and ovaries. Those data were correlated with forearm size and body mass, as well as with external reproductive characteristics. The diameter of the seminiferous tubule increased proportionately to testis mass and body weight, and larger males had greater testis mass. Sexually mature males were recorded throughout the year. Ovary histology revealed that females ovulate between July and December. Lactating females were recorded in nearly every month of the year. Noctilio leporinus has a bimodal polyestrous pattern, with an increase in the recruitment of juveniles between January and May.
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90
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Boratyński JS, Rusiński M, Kokurewicz T, Bereszyński A, Wojciechowski MS. Clustering Behavior in Wintering Greater Mouse-Eared BatsMyotis myotis— the Effect of Micro-Environmental Conditions. ACTA CHIROPTEROLOGICA 2012. [DOI: 10.3161/150811012x661738] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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91
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Dzal YA, Brigham RM. The tradeoff between torpor use and reproduction in little brown bats (Myotis lucifugus). J Comp Physiol B 2012; 183:279-88. [PMID: 22972361 DOI: 10.1007/s00360-012-0705-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Revised: 08/17/2012] [Accepted: 08/24/2012] [Indexed: 10/27/2022]
Abstract
In mammals, reproduction, especially for females is energetically demanding. Therefore, during the reproductive period females could potentially adjust patterns of thermoregulation and foraging in concert to minimise the energetic constraints associated with pregnancy and lactation. We assessed the influence of pregnancy, lactation, and post-lactation on torpor use and foraging behaviour by female little brown bats, Myotis lucifugus. We measured thermoregulation by recording skin temperature and foraging by tracking bats which carried temperature-sensitive radio-tags. We found that individuals, regardless of reproductive condition, used torpor, but the patterns of torpor use varied significantly between reproductive (pregnant and lactating) females and post-lactating females. As we predicted, reproductive females entered torpor for shorter bouts than post-lactating females. Although all females used torpor frequently, pregnant females spent less time in torpor, and maintained higher skin temperatures than either lactating or post-lactating females. This result suggests that delayed offspring development which has been associated with torpor use during pregnancy, may pose a higher risk to an individual's reproductive success than reduced milk production during lactation. Conversely, foraging behaviour of radio-tagged bats did not vary with reproductive condition, suggesting that even short, shallow bouts of torpor produce substantial energy savings, likely obviating the need to spend more time foraging. Our data clearly show that torpor use and reproduction are not mutually exclusive and that torpor use (no matter how short or shallow) is an important means of balancing the costs of reproduction for M. lucifugus.
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Affiliation(s)
- Yvonne A Dzal
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada.
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92
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Frequent arousal from hibernation linked to severity of infection and mortality in bats with white-nose syndrome. PLoS One 2012; 7:e38920. [PMID: 22745688 PMCID: PMC3380050 DOI: 10.1371/journal.pone.0038920] [Citation(s) in RCA: 197] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 05/16/2012] [Indexed: 12/19/2022] Open
Abstract
White-nose syndrome (WNS), an emerging infectious disease that has killed over 5.5 million hibernating bats, is named for the causative agent, a white fungus (Geomyces destructans (Gd)) that invades the skin of torpid bats. During hibernation, arousals to warm (euthermic) body temperatures are normal but deplete fat stores. Temperature-sensitive dataloggers were attached to the backs of 504 free-ranging little brown bats (Myotis lucifugus) in hibernacula located throughout the northeastern USA. Dataloggers were retrieved at the end of the hibernation season and complete profiles of skin temperature data were available from 83 bats, which were categorized as: (1) unaffected, (2) WNS-affected but alive at time of datalogger removal, or (3) WNS-affected but found dead at time of datalogger removal. Histological confirmation of WNS severity (as indexed by degree of fungal infection) as well as confirmation of presence/absence of DNA from Gd by PCR was determined for 26 animals. We demonstrated that WNS-affected bats aroused to euthermic body temperatures more frequently than unaffected bats, likely contributing to subsequent mortality. Within the subset of WNS-affected bats that were found dead at the time of datalogger removal, the number of arousal bouts since datalogger attachment significantly predicted date of death. Additionally, the severity of cutaneous Gd infection correlated with the number of arousal episodes from torpor during hibernation. Thus, increased frequency of arousal from torpor likely contributes to WNS-associated mortality, but the question of how Gd infection induces increased arousals remains unanswered.
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93
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Amaral TS, Carvalho TF, Silva MC, Goulart LS, Barros MS, Picanço MC, Neves CA, Freitas MB. Metabolic and Histopathological Alterations in the Fruit-Eating BatArtibeus lituratusInduced by the Organophosphorous Pesticide Fenthion. ACTA CHIROPTEROLOGICA 2012. [DOI: 10.3161/150811012x654420] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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94
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Iriarte-Diaz J, Riskin DK, Breuer KS, Swartz SM. Kinematic plasticity during flight in fruit bats: individual variability in response to loading. PLoS One 2012; 7:e36665. [PMID: 22615790 PMCID: PMC3352941 DOI: 10.1371/journal.pone.0036665] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 04/11/2012] [Indexed: 11/18/2022] Open
Abstract
All bats experience daily and seasonal fluctuation in body mass. An increase in mass requires changes in flight kinematics to produce the extra lift necessary to compensate for increased weight. How bats modify their kinematics to increase lift, however, is not well understood. In this study, we investigated the effect of a 20% increase in mass on flight kinematics for Cynopterus brachyotis, the lesser dog-faced fruit bat. We reconstructed the 3D wing kinematics and how they changed with the additional mass. Bats showed a marked change in wing kinematics in response to loading, but changes varied among individuals. Each bat adjusted a different combination of kinematic parameters to increase lift, indicating that aerodynamic force generation can be modulated in multiple ways. Two main kinematic strategies were distinguished: bats either changed the motion of the wings by primarily increasing wingbeat frequency, or changed the configuration of the wings by increasing wing area and camber. The complex, individual-dependent response to increased loading in our bats points to an underappreciated aspect of locomotor control, in which the inherent complexity of the biomechanical system allows for kinematic plasticity. The kinematic plasticity and functional redundancy observed in bat flight can have evolutionary consequences, such as an increase potential for morphological and kinematic diversification due to weakened locomotor trade-offs.
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Affiliation(s)
- Jose Iriarte-Diaz
- Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island, United States of America.
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95
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Vedder O. Individual birds advance offspring hatching in response to increased temperature after the start of laying. Oecologia 2012; 170:619-28. [DOI: 10.1007/s00442-012-2335-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Accepted: 04/11/2012] [Indexed: 10/28/2022]
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96
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Fly-and-Forage Strategy in the Bat Pipistrellus nathusii During Autumn Migration. ACTA CHIROPTEROLOGICA 2012. [DOI: 10.3161/150811012x661693] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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97
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Hallam TG, Federico P. The panzootic white-nose syndrome: an environmentally constrained disease? Transbound Emerg Dis 2011; 59:269-78. [PMID: 22044513 DOI: 10.1111/j.1865-1682.2011.01268.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
White-nose syndrome (WNS) is an emerging disease of hibernating bats probably caused by a pathogenic fungus, Geomyces destructans. The fungus has dispersed rapidly in the Northeastern United States and Canada and is presently a serious risk to hibernating bats of the mid-southern United States. Our objectives were to investigate how the environmental factors of temperature and resources impact the physiology of bats and apply this to explore possible effects of the fungus G. destructans on bats. Using a dynamic, physiologically based model parameterized for little brown bats (Myotis lucifugus), we found that the survival region defined in terms of minimal and maximal cave temperatures and bat lipid reserve levels exhibits plasticity as a function of cave temperature. During the pre-hibernation period, constellations of increased availability of fall and winter prey, reduced energy expenditure and lipogenic factors provide fat deposition in hibernator species that engender survival throughout the hibernation period. The model-derived survival region is used to demonstrate that small increases in lipid reserves allow survival under increasing maximum temperatures, which provides flexibility of bat persistence at the higher cave temperature ranges that may occur in the Southern United States. Antipodally, the lower-temperature survival range is bounded with minimum temperatures. Our results suggest that there is an environmental distinction between survival of bats in Southern and Northern US states, a relationship that could prove very important in managing WNS and its dispersal.
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Affiliation(s)
- T G Hallam
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA.
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98
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Evolutionary origin of bipolar disorder-revised: EOBD-R. Med Hypotheses 2011; 78:113-22. [PMID: 22036090 DOI: 10.1016/j.mehy.2011.10.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 09/07/2011] [Accepted: 10/04/2011] [Indexed: 11/19/2022]
Abstract
The hypothesis of the evolutionary origin of bipolar disorder (EOBD) synthesized ideas about the biological clock and seasonal shifts in mood (Rosenthal, Wehr) with theorizing that bipolar disorder descends from a pyknic (compact, cold-adapted) group (Kretchmer). The hypothesis suggested that bipolar behaviors evolved in the northern temperate zone as highly derived adaptations to the selective pressures of severe climatic conditions during the Pleistocene. Given evidence of Neandertal contributions to the human genome, the hypothesis is extended (EOBD-R) to suggest Neandertal as the ancestral source for bipolar vulnerability genes (susceptibility alleles). The EOBD-R hypothesis explains and integrates existing observations: bipolar disorder has the epidemiology of an adaptation; it is correlated with a cold-adapted build, and its moods vary according to light and season. Since the hypothesis was first published, data consistent with it have continued to appear. Individuals with seasonal affective disorder, which is related to bipolar disorder, have been shown to manifest a biological signal of season change similar to that found in hibernating animals. The involvement of the circadian gene network in the pathophysiology of bipolar disorder has been confirmed. Because selective pressures during the Pleistocene would have been greatest for women of reproductive age, they are expected to manifest winter depression more than males or younger females, which is the case. (This sex difference is also found in hibernating mammals.) Because it is hypothesized that the evolution of bipolar disorder took place in the northern temperate zone during the Pleistocene, it is not expected that individuals of African descent, lacking Neandertal genes, will manifest circular bipolar I disorder, and in fact, the incidence of bipolar disorder among black individuals is less than among whites. A definitive test of the hypothesis is proposed: It is predicted that the bipolar and Neandertal genomes will be more similar than the modern human and Neandertal genomes, and the modern human and San and Yoruba genomes will be more similar than the bipolar and San and Yoruba genomes. Failure to confirm these predictions will falsify the EOBD-R hypothesis. The EOBD-R hypothesis has important implications in the search for bipolar vulnerability genes and our understanding of ourselves and our Neandertal ancestor. At a practical level, confirmation of the EOBD-R hypothesis will boost interest and research in the prevention and management of bipolar symptoms by manipulation of ambient light.
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99
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McNamara JM, Barta Z, Klaassen M, Bauer S. Cues and the optimal timing of activities under environmental changes. Ecol Lett 2011; 14:1183-90. [PMID: 22017534 PMCID: PMC3258420 DOI: 10.1111/j.1461-0248.2011.01686.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Organisms time activities by using environmental cues to forecast the future availability of important resources. Presently, there is limited understanding of the relationships between cues and optimal timing, and especially about how this relationship will be affected by environmental changes. We develop a general model to explore the relation between a cue and the optimal timing of an important life history activity. The model quantifies the fitness loss for organisms failing to time behaviours optimally. We decompose the immediate change in fitness resulting from environmental changes into a component that is due to changes in the predictive power of the cue and a component that derives from the mismatch of the old response to the cue to the new environmental conditions. Our results show that consequences may range from negative, neutral to positive and are highly dependent on how cue and optimal timing and their relation are specifically affected by environmental changes.
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100
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Jonasson KA, Willis CKR. Changes in body condition of hibernating bats support the thrifty female hypothesis and predict consequences for populations with white-nose syndrome. PLoS One 2011; 6:e21061. [PMID: 21731647 PMCID: PMC3120823 DOI: 10.1371/journal.pone.0021061] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 05/19/2011] [Indexed: 11/19/2022] Open
Abstract
White-nose syndrome (WNS) is a new disease of bats that has devastated populations in eastern North America. Infection with the fungus, Geomyces destructans, is thought to increase the time bats spend out of torpor during hibernation, leading to starvation. Little is known about hibernation in healthy, free-ranging bats and more data are needed to help predict consequences of WNS. Trade-offs presumably exist between the energetic benefits and physiological/ecological costs of torpor, leading to the prediction that the relative importance of spring energy reserves should affect an individual's use of torpor and depletion of energy reserves during winter. Myotis lucifugus mate during fall and winter but females do not become pregnant until after spring emergence. Thus, female reproductive success depends on spring fat reserves while male reproductive success does not. Consequently, females should be "thrifty" in their use of fat compared to males. We measured body condition index (BCI; mass/forearm length) of 432 M. lucifugus in Manitoba, Canada during the winter of 2009/2010. Bats were captured during the fall mating period (n = 200), early hibernation (n = 125), and late hibernation (n = 128). Adult females entered hibernation with greater fat reserves and consumed those reserves more slowly than adult males and young of the year. Consequently, adult females may be more likely than males or young of the year to survive the disruption of energy balance associated with WNS, although surviving females may not have sufficient reserves to support reproduction.
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Affiliation(s)
- Kristin A. Jonasson
- Department of Biology, Centre for Forest Interdisciplinary Research (C-FIR), University of Winnipeg, Winnipeg, Canada
| | - Craig K. R. Willis
- Department of Biology, Centre for Forest Interdisciplinary Research (C-FIR), University of Winnipeg, Winnipeg, Canada
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