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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Distribuição, nicho potencial e ecologia morfológica do gênero Enyalius (Squamata, Leiosauridae) : testes de hipotéses para lagartos de florestas continentais brasileiras

Barreto-Lima, André Felipe January 2012 (has links)
No capítulo 1 os principais fatores envolvidos com a distribuição geográfica do gênero Enyalius foram a temperatura média anual, a latitude e a amplitude média da temperatura diurna, indicando uma possível adaptação termal do gênero. A distribuição potencial do grupo refletiu na variação geográfica na morfologia, como demonstrado pelas diferenças no tamanho do corpo e estruturas morfológicas, que foram explicadas por variáveis climáticas, espaciais e estruturais do ambiente. A regra de Allen corroborou com os padrões da variação na morfologia de Enyalius, que foram correlacionados com as condições térmicas e geográficas. Os padrões de variação morfológica também foram associados com cobertura vegetal (e talvez a disponibilidade de água nas diferentes regiões), que pode exercer influência sobre a adaptação morfológica de Enyalius e explicar parte do crescimento diferencial alométrico sobre a vasta área geográfica. A hipótese de adaptação térmica deve ser a base para explicar a distribuição de Enyalius em ambientes de florestas do Brasil. No capítulo 2 estudamos as áreas de distribruição potencial de cada espécie do grupo e encontramos para a maioria delas características ambientais gerais que foram importantes para a ocorrência do gênero nos seus ambientes. A latitude e a amplitude média da temperatura diurna, que se sobreporam na maioria dos modelos de nicho potencial, ao longo da costa brasileira, deve caracterizar a distribuição principal das espécies de Enyalius no Domínio Florestal Atlântico. Isso nos indicou um “padrão geral” de fatores básicos importantes para a ocorrência do grupo neste bioma e que, provavelmente, parte dos nichos ecológicos similares entre algumas espécies, em geral, ocorreram por influência ambiental de ampla magnitude em associação à plasticidade fenotípica das espécies como resposta ecológica adaptativa. No capítulo 3, nós encontramos algumas respostas para as espécies de Enyalius, havendo padrões morfológicos e ambientais específicos associados independentemente da relação filogenética ou da proximidade geográfica em que estas se encontram. Acreditamos que as características ambientais e o uso destas, como recursos, devem influenciar mais sobre a ocorrência das espécies em seus hábitats (pressão de seleção natural) do que por uma questão de inércia filogenética herdada ao grupo. Este estudo também indicou que determinadas mudanças evolutivas nas proporções e no tamanho do corpo das espécies de Enyalius devem estar associadas à divergência de hábitats e suas características e/ou ao uso diferente de substratos entre as espécies de lagartos, e que, consequentemente, necessitam de maiores investigações para o conhecimento das causas das relações ecológicas reveladas aqui. Por fim, os padrões observados sobre a variação morfológica nas espécies de Enyalius devem ser uma conseqüência direta de respostas adaptativas a ação das condições ambientais locais (e.g. seleção natural), o que por sua vez nos revelou grande plasticidade adaptativa das espécies através de suas ecologias em ambientes de continente. / In the first chapter, we saw that the main factors affecting the Enyalius’ geographical distribution were the annual mean temperature, latitude, and the mean diurnal temperature, which indicates a possible thermal adaptation as a base to explain the group distribution. Enyalius distribution was reflected in the morphological geographical variation, as demonstrated by the differences in the body size and morphological structures, which were explained by climatic, spatial and structural variables. The Allen rule was corroborated, as patterns in the morphological variation in Enyalius were correlated with thermal and geographical conditions. The thermal adaptation hypothesis may be the basis to explain Enyalius distribution in different Brazilian forests. In the second chapter we studied the potential distribution areas for each species in the group, and we identified the general environmental characteristics affecting the species occurrence in their habitats, for most species. We suggest that variables such as latitude and mean amplitude of daily temperature along the Brazilian coast overlapped in most of our models, characterizing the main distribution of the species belonging to the genus Enyalius in the Atlantic Forest. In the third chapter, we found that there are morphological and environmental patterns associated with the species, independent of their phylogenetic or geographical relationship. We observed that environmental features seem to be more critical to determine the species occurrence than their evolutionary heritage (e.g. philogenetic inertia). Finally, this study indicated that some evolutionary changes in body size and proportions might be associated to the divergence in habitat requirements and/or the differences in substrate use, which need further investigation. We conclude that the observed morphological variation in Enyalius can be a direct consequence of adaptative responses to local environmental conditions, which demonstrated the high phenotipic plasticity, based on their ecology in environments from mainland.
22

Distribuição, nicho potencial e ecologia morfológica do gênero Enyalius (Squamata, Leiosauridae) : testes de hipotéses para lagartos de florestas continentais brasileiras

Barreto-Lima, André Felipe January 2012 (has links)
No capítulo 1 os principais fatores envolvidos com a distribuição geográfica do gênero Enyalius foram a temperatura média anual, a latitude e a amplitude média da temperatura diurna, indicando uma possível adaptação termal do gênero. A distribuição potencial do grupo refletiu na variação geográfica na morfologia, como demonstrado pelas diferenças no tamanho do corpo e estruturas morfológicas, que foram explicadas por variáveis climáticas, espaciais e estruturais do ambiente. A regra de Allen corroborou com os padrões da variação na morfologia de Enyalius, que foram correlacionados com as condições térmicas e geográficas. Os padrões de variação morfológica também foram associados com cobertura vegetal (e talvez a disponibilidade de água nas diferentes regiões), que pode exercer influência sobre a adaptação morfológica de Enyalius e explicar parte do crescimento diferencial alométrico sobre a vasta área geográfica. A hipótese de adaptação térmica deve ser a base para explicar a distribuição de Enyalius em ambientes de florestas do Brasil. No capítulo 2 estudamos as áreas de distribruição potencial de cada espécie do grupo e encontramos para a maioria delas características ambientais gerais que foram importantes para a ocorrência do gênero nos seus ambientes. A latitude e a amplitude média da temperatura diurna, que se sobreporam na maioria dos modelos de nicho potencial, ao longo da costa brasileira, deve caracterizar a distribuição principal das espécies de Enyalius no Domínio Florestal Atlântico. Isso nos indicou um “padrão geral” de fatores básicos importantes para a ocorrência do grupo neste bioma e que, provavelmente, parte dos nichos ecológicos similares entre algumas espécies, em geral, ocorreram por influência ambiental de ampla magnitude em associação à plasticidade fenotípica das espécies como resposta ecológica adaptativa. No capítulo 3, nós encontramos algumas respostas para as espécies de Enyalius, havendo padrões morfológicos e ambientais específicos associados independentemente da relação filogenética ou da proximidade geográfica em que estas se encontram. Acreditamos que as características ambientais e o uso destas, como recursos, devem influenciar mais sobre a ocorrência das espécies em seus hábitats (pressão de seleção natural) do que por uma questão de inércia filogenética herdada ao grupo. Este estudo também indicou que determinadas mudanças evolutivas nas proporções e no tamanho do corpo das espécies de Enyalius devem estar associadas à divergência de hábitats e suas características e/ou ao uso diferente de substratos entre as espécies de lagartos, e que, consequentemente, necessitam de maiores investigações para o conhecimento das causas das relações ecológicas reveladas aqui. Por fim, os padrões observados sobre a variação morfológica nas espécies de Enyalius devem ser uma conseqüência direta de respostas adaptativas a ação das condições ambientais locais (e.g. seleção natural), o que por sua vez nos revelou grande plasticidade adaptativa das espécies através de suas ecologias em ambientes de continente. / In the first chapter, we saw that the main factors affecting the Enyalius’ geographical distribution were the annual mean temperature, latitude, and the mean diurnal temperature, which indicates a possible thermal adaptation as a base to explain the group distribution. Enyalius distribution was reflected in the morphological geographical variation, as demonstrated by the differences in the body size and morphological structures, which were explained by climatic, spatial and structural variables. The Allen rule was corroborated, as patterns in the morphological variation in Enyalius were correlated with thermal and geographical conditions. The thermal adaptation hypothesis may be the basis to explain Enyalius distribution in different Brazilian forests. In the second chapter we studied the potential distribution areas for each species in the group, and we identified the general environmental characteristics affecting the species occurrence in their habitats, for most species. We suggest that variables such as latitude and mean amplitude of daily temperature along the Brazilian coast overlapped in most of our models, characterizing the main distribution of the species belonging to the genus Enyalius in the Atlantic Forest. In the third chapter, we found that there are morphological and environmental patterns associated with the species, independent of their phylogenetic or geographical relationship. We observed that environmental features seem to be more critical to determine the species occurrence than their evolutionary heritage (e.g. philogenetic inertia). Finally, this study indicated that some evolutionary changes in body size and proportions might be associated to the divergence in habitat requirements and/or the differences in substrate use, which need further investigation. We conclude that the observed morphological variation in Enyalius can be a direct consequence of adaptative responses to local environmental conditions, which demonstrated the high phenotipic plasticity, based on their ecology in environments from mainland.
23

Dinâmica da partilha dos recursos alimentares entre peixes piscívoros numa lagoa do semiárido brasileiro

COLLIER, Carolina Alves 28 February 2012 (has links)
Submitted by (ana.araujo@ufrpe.br) on 2016-08-22T11:40:08Z No. of bitstreams: 1 Carolina Alves Collier.pdf: 1967577 bytes, checksum: 200ee0c9c05fb39ab23840a268dff357 (MD5) / Made available in DSpace on 2016-08-22T11:40:09Z (GMT). No. of bitstreams: 1 Carolina Alves Collier.pdf: 1967577 bytes, checksum: 200ee0c9c05fb39ab23840a268dff357 (MD5) Previous issue date: 2012-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The dynamics of resource partitioning among species from the same trophic guild, reduces competition and allows coexistence between them. Such sharing can result from different environmental performance and morphological changes resulting from the differential use of food resources. In this study, we evaluated the dynamic of partitioning of food resources in a guild of piscivorous fish, considering the ecomorphology and feeding of the species. Samples were collected monthly, between March/2007 and February/2008, the pond Curralinho, inserted in the semiaridnortheast. We evaluated the five most abundant species ofpiscivorous guild, and they are Acestrorhynchus lacustris, Acestrorhynchus britskii, Hoplias malabaricus, Pygocentrus piraya e Serrasalmus brandtii. The association of the informations trophics and ecomorphologicals of the evaluated piscivores resulted in similar patterns of clustering, demonstrating that the species that used different food resources, also possessed distinct morphological. The first group focused concentrated the two Serrasalminae species, while the second contained Hoplias malabaricus and two species of Acestrorhynchus. Among the species of Serrasalminae and Acestrorhynchus, morphological changes were not observed. However, among the members of Serrasalminae differences were observed in the strategies and food preferences, indicating a partitioning of resources between them. Such sharing can be evidenced by the intermediate value of dietary overlap between these two species. The food overlap index shows high values just within the group formed by H malabaricus and the two Acestrorhynchus species, however H. malabaricus differed in their strategy and food preference, which can contribute to reducing the potentialcompetitive with Acestrorhynchus. Just between the two species Acestrorhynchus did not show differences in strategy and food preference, indicating that theyhad the highest competitive potential between piscivorous evaluated. We emphasize the importance of the concomitant use of analysis ecomorphological and feeding, which is essential to a better understanding of the real trophic sharing. / A dinâmica da partilha de recursos, entre espécies de uma mesma guilda trófica, reduz a competição e possibilita a coexistência entre elas. Essa partilha pode decorrer do desempenho ecológico diferenciado resultante de variações morfológicas e da utilização diferenciada dos recursos alimentares. Neste estudo, avaliou-se a dinâmica da partilha de recursos alimentares numa guilda de peixes piscívoros, considerando a ecomorfologia e alimentação das espécies. As coletas foram realizadas mensalmente, entre março/2007 e fevereiro/2008, na lagoa Curralinho, inserida no semiárido nordestino. Foram avaliadas as cinco espécies mais abundantes da guilda dos piscívoros, sendo elas Acestrorhynchus lacustris, Acestrorhynchus britskii, Hoplias malabaricus, Pygocentrus piraya e Serrasalmus brandtii. A associação das informações ecomorfológicas e tróficas dos piscívoros avaliados resultou em padrões similares de agrupamento, demonstrando que as espécies que utilizaram recursos alimentares diferenciados, também possuíram padrões morfológicos distintos. O primeiro grupo concentrou as duas espécies de Serrasalminae, enquanto o segundo conteve Hoplias malabaricus e as duas espécies de Acestrorhynchus. Entre as espécies de Serrasalminae e Acestrorhynchus não foram observadas variações morfológicas. No entanto, entre os integrantes de Serrasalminae, foram observadas diferenças nas estratégias e preferências alimentares, indicando uma partilha dos recursos entre elas. Essa partilha pode ser evidenciada pelo valor intermediário de sobreposição alimentar entre estas duas espécies. O índice de sobreposição alimentar apresentou altos valores apenas dentro do grupo formado por H. malabaricus e as duas espécies de Acestrorhynchus,, entretanto H. malabaricus diferiu em sua estratégia e preferência alimentar, o que pode contribuir para a redução do potencial competitivo com Acestrorhynchus. Apenas entre as duas espécies de Acestrorhynchus não foram evidenciadas diferenças na estratégia e preferência alimentar, indicando que elas apresentaram o mais elevado potencial competitivo entre os piscívoros avaliados. Ressaltamos a importância da utilização concomitante de análises ecomorfológicas e de alimentação, que são indispensáveis para uma melhor compreensão da real partilha trófica.
24

Padrões de ocorrência e composição de girinos do cerrado: importância da interação fenótipo-ambiente e do espaço / Ocurrence patterns and composition of cerrado tadpoles: importance of phenotype-environment interaction and space

Marques, Núbia Carla Santos 18 March 2016 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-07-28T16:40:34Z No. of bitstreams: 2 Tese - Núbia Carla Santos Marques - 2016.pdf: 2449653 bytes, checksum: 5c7b386d16140f146b1b891f400d91dc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-01T12:57:44Z (GMT) No. of bitstreams: 2 Tese - Núbia Carla Santos Marques - 2016.pdf: 2449653 bytes, checksum: 5c7b386d16140f146b1b891f400d91dc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-01T12:57:44Z (GMT). No. of bitstreams: 2 Tese - Núbia Carla Santos Marques - 2016.pdf: 2449653 bytes, checksum: 5c7b386d16140f146b1b891f400d91dc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Tadpoles of anuran species that occur in Cerrado can be found in several types of habitats. This habitat plasticity is possible because tadpoles have a high diversification in morphological adaptations that ensure an optimal performance in different ecological contexts. In this study, we were interested to investigate how environmental and spatial factors can explain the patterns of occurrence and distribution of tadpoles in Brazilian Cerrado and the interaction with tadpoles‘ morphological variation. We found that occurrence of tadpoles was explained by environmental variables and seven morphology-environment interactions. The most common tadpoles morphological change is related to body and tail size, and in eyes, nostril and mouth positions. Tadpoles‘ assemblage composition and morphological variation have significantly affected by spatial factors, but local environmental factors also play a major role defining morphological variation, although to a small degree. We discuss ecomorphological guilds of tadpoles and suggest that in larger guild (benthic tadpoles) can have morphology-environment interaction, while in the smaller ones (nektonic tadpoles) changes in feeding behavior and habitat selection is more common. There is a lack of knowledge about amphibian diversity, abundance and occurrence in Brazilian Cerrado and our study provide additional information about environmental and spatial factors that contribute to the patterns of occurrence and distribution of species. Abiotic factors (e.g. vegetation in ponds and land use) and spatial factors can contribute to individuals‘ phenotype changes and play a role in patterns of occurrence and tadpoles‘ assemblage composition. / Girinos de anuros que ocorrem no Cerrado podem ser encontrados em diversos tipos de habitats, sendo essa plasticidade de hábitats possível devido as adaptações morfológicas que asseguram uma boa performance em diferentes contextos ecológicos. Nesse presente estudo, nós investigamos como fatores ambientais e espaciais podem explicar os padrões de ocorrência e distribuição de girinos do Cerrado, além da interação com a variação morfológica dos indivíduos. A ocorrência dos girinos foi explicada por variáveis ambientais e sete interações morfologia-ambiente, sendo as mudanças morfológicas mais comuns: variação no tamanho do corpo e da cauda e mudanças nas posições dos olhos, narina e boca. A composição e a variação morfológica da assembleia de girinos são significativamente afetadas por fatores espaciais, mas fatores ambientais locais também desempenham um importante papel definindo a variação morfológica dos girinos, embora em um menor grau. Abordamos as guildas ecomorfológicas dos girinos e sugerimos que em guildas maiores pode haver variação morfológica atreladas as variáveis ambientais, enquanto nas menores mudanças no comportamento de forrageio e na seleção de hábitat são mais comuns. O presente estudo fornece informações adicionais sobre fatores ambientais e espaciais que contribuem para os padrões de ocorrência e distribuições das espécies de anuros. Fatores abióticos, por exemplo presença de vegetação e uso da terra ao redor da poça, também podem estar agindo mudando o fenótipo dos indivíduos e determinando a ocorrência e a composição das assembleias. Fatores espaciais também são determinantes em assembleias de girinos, sendo um grupo que possui baixa capacidade de dispersão. Girinos estão, em geral, limitados a poça que foi previamente escolhida pelo adulto, e processos neutros como nascimentos e mortes aleatórias na população podem operar nas assembleias.
25

Evaluation of the Efficacy of the Minimum Size Rule in the Red Grouper and Red Snapper Fisheries With Respect to J and Circle Hook Mortality and Barotrauma and the Consequences for Survival and Movement

Burns, Karen Mary 03 April 2009 (has links)
Although closed seasons, bag limits and quotas are used to manage fishes within the Grouper/Snapper Complex off the southeastern United States, size limits are the cornerstone of fisheries management. Because fishers must release all undersized fishes despite fish condition, this regulation has created a mandatory catch and release system. Inherent in this management strategy is the supposition that these undersized fish survive in sufficient numbers so as to justify this regulation. To satisfy this criteria fish mortality must be low and released fish must also experience minimal sub-lethal effects. Determination of sublethal effects and evaluation of their potential impairment and duration of injury are required to develop effective physiology-based criteria to evaluate the efficacy of the minimum size rule. The goal of this research was to evaluate some aspects of the efficacy of the minimum size rule in the red grouper and red snapper fisheries off Florida by collecting traditional fisheries data and analyzing it in light of fish physiology, ecomorphology and behavior. Study objectives included 1) determination of the causes for the differences of hook mortality for red grouper and red snapper in the recreational and recreational-for-hire fisheries by necropsy of acute and latent mortalities, analysis of tag and recapture data for both J and circle hooks, determination of fish dentition and any differences in feeding behavior, 2) examination of the effects of rapid depression from depth on fish survival by inspection and comparison of the red grouper and red snapper swim bladders in both healthy and swim bladder ruptured fish from various water depths, comparison of tag and recapture data, investigation of the effects of fish venting, and laboratory simulations using fish hyperbaric chambers to determine healing and survival from rapid depression trauma, 3) analysis of movement patterns of tagged fish and 4) evaluation of some of the consequences imposed by the minimum size limit based on study results.
26

Ecomorphological and Genetic Investigations into the Utah Lake, UT Sucker Complex with Comparisons to the Jackson Lake, WY Sucker Complex

Cole, David 01 May 2014 (has links)
Ecomorphological specialization within Catostomidae in several large western North American lakes has produced populations including typical benthic suckers (Catostomus) and lakesuckers (Chasmistes), mid-water planktivores, with a continuum of morphologies existing between them. All extant lakesuckers are endangered, and population declines have been attributed in part to hybridization with sympatric Catostomus spp. Chapter 2 describes assessment for concordance of morphological and genetic variation in suckers in Utah Lake, Utah (June sucker, Chasmistes liorus; Utah sucker, Catostomus ardens; and suckers of intermediate morphology) by comparing a morphological analysis with amplified fragment length polymorphism and microsatellite analyses. Suckers were differentiated using characters associated with presumed feeding strategies: zooplanktivory (June sucker) and benthivory (Utah sucker). No molecular evidence was found for deep genetic divergence between morphs or for hybridization among ancient lineages. Slight population structuring accompanied substantial morphological variation. Chapter 3 describes the investigation of distribution and movement, spawning behavior, and diet of suckers in Utah Lake and their growth at different densities in a laboratory experiment. Acoustic / radio telemetry revealed little difference in movement and distribution of June sucker and Utah sucker or in timing of spawning runs. Stable isotopes analysis revealed that Utah sucker were enriched in 13C relative to June sucker as presumed diets would predict. Intermediate morphs were intermediate for δ13C and δ15N. Neither species nor density was a significant predictor of growth rate of June sucker or Utah sucker reared at different conspecific densities. Chapter 4 examines morphology, genetics, and diet of the sucker population inJackson Lake, Wyoming, once home of the extinct Snake River sucker, Chasmistes muriei, a lakesucker known from a single specimen. Currently, suckers in Jackson Lake are identified as Utah sucker; however, recently sampled individuals resemble lakesucker. No molecular evidence was found for deep genetic divergence between lakesucker and benthic morphs or for hybridization among ancient lineages. The benthic morph was significantly enriched in 13C relative to the lakesucker morph, consistent with presumed diets. Morphologically, the lone Snake River sucker holotype specimen grouped strongly with extant lakesucker morphs, suggesting that the status of the Snake River sucker be updated accordingly.
27

Comparative Morphology of the Forelimb Digging Apparatus in Armadillos (Xenarthra: Cingulata, Dasypodidae)

Marshall, Sarah K. 24 August 2018 (has links)
No description available.
28

Ecology, Morphology, and Behavior in the New World Wood Warblers

Gray, Brandan L. 20 September 2019 (has links)
No description available.
29

Quantifying the link between craniodental morphology and diet in Soricidae using geometric morphometrics

Tse, Yuen Ting January 2020 (has links)
No description available.
30

INSIGHTS INTO THE ECOLOGY OF VESPERTILIONIDAE THORUGH SKULL MORPHOLOGY AND ROOST SELECTION

Matthew S Dunn (17552733) 08 December 2023 (has links)
<p dir="ltr">Bat population numbers are declining in the Midwestern United States. Reasons for decline are multifaceted (habitat degradation, fatalities at wind turbines, White Nose Syndrome, and declining insect populations), and many species are listed as endangered (Myotis sodalis, Myotis septentrionalis, Perimyotis subflavus). Other species in the Midwestern United States have no conservation status (Eptesicus fuscus), or are only listed as a species of concern (Lasiurus cinereus, Lasiurus borealis, Lasionycteris noctivagans). Bats play a crucial role in our ecosystems, providing both ecological and economic benefit as pollinators and insect population regulators. Thus, conserving these species is vital. To gain better insight into the ecology of Midwestern bat species I studied five species in two respects. First, I investigated the availability of roosts for a colony of endangered Myotis sodalis near Indianapolis. This colony has withstood high levels of urbanization and habitat degradation. Therefore, understanding what aspects of the roosting area has allowed for continued use by the colony is crucial for future conservation efforts. I used an Akaike’s Information Criteria approach to rank models that best differentiate between the current roosting area and surrounding landscape. I identified that the roosting area contained a greater number of large standing dead trees (Snags >42.6 cm) that are able to serve as primary roosts for the colony. These results demonstrate that a colony of Indiana bats may be able to withstand urbanization if they have enough large DBH snags available in the area. Future conservation efforts in a heavily urbanized environment should focus on the maintaining large snags as primary roosts. Second, I studied the morphological variation of four species (Lasiurus cinereus, Lasiurus borealis, Lasionycteris noctivagans, and Eptesicus fuscus) to parse out differences that may lead to niche specialization. These four species share habitat and foraging range and therefore may directly compete for resources. However, despite declining insect populations these four species have moderately stable populations. I collected approximately 30 craniums and mandibles for each species and compared the linear size differences between landmarks and the overall shape variation from these landmarks. Due to different phylogenies and body sizes, the four species were different from one another in all 24 linear measurements. In regards to shape variation, the Eptesicini bat craniums had characteristics of more gracile species. In addition, the mandibles of Eptesicini were highly distinct. Lasionycteris noctivagans was the least durable and Eptesicus fuscus had 10 specialization for hard bodied prey consumption. These results suggest potential niche specialization due variation in morphology.</p>

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