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Assessment of morphological and molecular genetic variation of freshwater mussel species belonging to the genera Fusconaia, Pleurobema, and Pleuronaia in the upper Tennessee River basinSchilling, Daniel Edward 07 July 2015 (has links)
Select freshwater mussels in the genera Fusconaia, Pleurobema, and Pleuronaia were collected primarily in the upper Tennessee River basin from 2012 to 2014 for phylogenetic and morphological assessments. Freshwater mussels in these genera are similar in appearance, hence the need for phylogenetic verification and morphological assessment. Phylogenetic analyses of the mitochondrial gene ND1 and the nuclear gene ITS1 revealed three unrecognized, phylogenetically distinct species. These species were separated from their closest congener by 2.85%, 3.17%, and 6.32% based on pairwise genetic distances of ND1. Gaps created from aligning ITS1 sequences were coded as fifth characters, which phylogenetically separated most closely related species. Analyses of ND1 agreed with previous literature on the phylogenetic distinctiveness of Pleuronaia species, with the exception of the DNA sequences of P. gibberum, which grouped outside this genus based on the analyses conducted in this study.
Morphological variation was recorded for eight of the species to include quantitative and qualitative characters as well as geometric morphometric analyses. Three decision trees were created from quantitative and qualitative characters using classification and regression tree analyses. The best-performing tree used quantitative and qualitative characters describing shell-only scenarios and obtained 80.6% correct classification on terminal nodes. Canonical variates analysis on geometric morphometric shell data revealed large morphological overlap between species. Goodall's F-tests between pairs of species revealed significant differences (a=0.05) between all but one species pairs; however, examination of landmarks on shells concluded large overlap of landmarks between species pairs. Lack of morphologically distinct characters to readily identify these phylogenetically distinct species indicates large morphological overlap among these species. Biologists need to be cognizant that morphologically cryptic species may exist in systems often explored.
Three dichotomous keys were created from classification trees to identify select individuals in the genera Fusconaia, Pleurobema, and Pleuronaia; two of these keys, one for shells and one for live mussels were tested by participants with varying mussel identification skills to represent novices and experts. Both keys used continuous (quantitative) and categorical variables to guide participants to identifications. Novices, who had no prior mussel identification experience, correctly identified mussels with a 50% accuracy using the shell key and with a 51% accuracy using the live key. Experts, who had at least three years of experience identifying mussels, correctly identified mussels with a 58% accuracy using the shell key and with a 68% accuracy using the live key; however one expert noted that they did not use the live key to correctly identify one mussel. Morphological overlap of variables between mussels likely resulted in failure to consistently identify mussels correctly.
Important management decisions and project implementations require accurate assessment of species' localities and populations. Incorrect species identification could hinder species' recovery efforts or prevent projects that otherwise could have continued if species are misidentified. If a mussel collection is thought to be a new record or could affect a project, I recommend that molecular genetic identifications be used to verify the species identity. / Master of Science
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Distribuição das assembleias de girinos associadas a riachos da Reserva Ecológica de Guapiaçu, Cachoeiras de Macacú, Rio de Janeiro, Brasil / Distribution of stream-dwelling tadpoles of the Reserva Ecológica de Guapiaçu, Cachoeiras de Macacú, Rio de Janeiro, BrazilVitor Nelson Teixeira Borges Júnior 22 January 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Os girinos são organismos diversos e abundantes nos pequenos riachos de cabeceira
de florestas tropicais e constituem importantes componentes da diversidade biológica, da
trófica e funcional dos sistemas aquáticos. Diferentes características estruturais e limnológicas
dos ambientes aquáticos influenciam a organização das assembleias de girinos. Embora o
estágio larvar dos anuros seja o mais vulnerável de seu ciclo de vida, sujeito a elevadas taxas
de mortalidade, as pesquisas sobre girinos na região neotropical ainda são pouco
representativas diante da elevada diversidade de anfíbios desta região e ferramentas que
permitam a sua identificação ainda são escassas. Nesta tese, dividida em três capítulos,
apresento uma compilação das informações relacionadas aos principais fatores que afetam as
assembleias de girinos na região tropical (Capítulo 1), a caracterização morfológica dos
girinos encontrados nos riachos durante o estudo e uma proposta de chave dicotômica de
identificação (Capítulo 2) e avalio a importância relativa da posição geográfica e da variação
temporal de fatores ambientais locais sobre as assembleias de girinos, assim como a
correlação entre as espécies de girinos e as variáveis ambientais de 10 riachos, ao longo de 15
meses, nas florestas da REGUA (Capítulo 3). Há pelo menos oito tendências relacionadas à
distribuição das assembleias de girinos: (1) o tamanho dos riachos e a diversidade de
microhabitats são importantes características abióticas influenciando a riqueza e a composição
de espécies; (2) em poças, o gradiente de permanência (e.g., hidroperíodo) e a
heterogeneidade do habitat são os principais fatores moldando as assembleias de girinos; (3) a
composição de espécies parece ser um parâmetro das assembleias mais relevante do que a
riqueza de espécies e deve ser primeiramente considerado durante o planejamento de ações
conservacionistas de anuros associados a poças e riachos; (4) a predação parece ser a
interação biótica mais importante na estruturação das assembleias de girinos, com predadores
vertebrados (e.g. peixes) sendo mais vorazes em habitats permanentes e predadores
invertebrados (e.g. larvas de odonata) sendo mais vorazes em ambientes temporários; (5) os
girinos podem exercer um efeito regulatório, predando ovos e girinos recém eclodidos; (6) o
uso do microhabitat varia em função da escolha do habitat reprodutivo pelos adultos, presença
de predadores, filogenia, estágio de desenvolvimento e heterogeneidade do habitat; (7) os
fatores históricos restringem os habitats reprodutivos que uma espécie utiliza, impondo
restrições comportamentais e fisiológicas; (8) a variação temporal nos fatores bióticos (e.g.,
fatores de risco), abióticos (e.g., distribuição de chuvas), e no padrão de reprodução das
espécies pode interferir na estrutura das assembleias de girinos tropicais. A variação temporal
na heterogeneidade ambiental dos riachos da REGUA resultou na previsibilidade das
assembleias locais de girinos, sendo que os parâmetros ambientais explicaram 23% da
variação na sua composição. Os parâmetros espaciais explicaram uma porção menor da
variação nas assembleias (16%), enquanto uma porção relativamente elevada da variação
temporal da heterogeneidade ambiental foi espacialmente estruturada (18%). As variáveis
abióticas que apresentaram as maiores correlação com a composição das assembleias de
girinos foram a proporção de folhiço e de rochas no fundo do riacho, e secundariamente a
profundidade, a condutividade e a temperatura. O gradiente gerado pela proporção de folhiço
e de rochas representou a transição entre riachos permanentes e intermitentes. Este gradiente
proporcionou o turnover de espécies, o qual também seguiu um gradiente de condutividade,
temperatura, profundidade, e em menor extensão, de hidroperíodo e largura, que estiveram
fortemente associado ao grau de permanência dos riachos. Estes resultados corroboram tanto
a hipótese do controle ambiental, como do controle biótico de comunidades e indicam que a
variação temporal da heterogeneidade ambiental e a variação na posição geográfica são
importantes para a estruturação local de assembleias de girinos da REGUA. Os resultados
também permitiram distinguir entre assembleias de girinos exclusivas de riachos
permanentes, exclusivas de riachos intermitentes e aquelas registradas nos dois tipos de
riachos. Os resultados deste capítulo são relevantes para compreender em que extensão os
efeitos da variação temporal na heterogeneidade ambiental e de processos espaciais afetam
localmente a estruturação de assembleias de girinos. / Tadpoles are diverse and abundant organisms in headwater streams of tropical
rainforests and constitute important components of biological, trophic and functional
diversity. Furthermore, different structural (e.g. size, depth, microhabitat availability) and
limnological (e.g. conductivity, temperature) characteristics affect tadpole organization.
Although the larval stage is the most vulnerable in anurans, subject to high mortality rates,
researches on tadpoles in the neotropics, as tools for their identification, remain scarce face
the high diversity of anurans found in this region. In this thesis, I present a compilation of
information on the main factors affecting tadpole assemblages in the tropics (Chapter 1), the
morphological characterization of tadpoles found in streams during the study with a propose
of dichotomous key of identification (Chapter 2), and evaluated the relative importance of
geographical position and the temporal variation o local environmental factors on tadpole
assemblages through 15 months in 10 small streams in the Atlantic Forest of Reserva
Ecológica do Guapiaçu (REGUA), municipality of Cachoeiras de Macacú, Rio de Janeiro,
Brazil. I also investigated the correlation between tadpoles and the environmental variables of
streams (Chapter 3). We can recognize at least eigth major trends regarding the distribution
and structure of tropical tadpole assemblages: (1) stream size and microhabitat diversity are
important abiotic features influencing species richness and composition; (2) in ponds, the
permanence gradient (e.g., hydroperiod), and the heterogeneity of habitat are the main factors
modeling tropical tadpole assemblages; (3) species composition seems to be a more relevant
assemblage parameter than species richness and should be first considered when planning
conservation of both pond and stream-dwelling anurans; (4) predation seems to be the most
important biotic interaction structuring tropical tadpole assemblages, with vertebrate predators
(e.g., fishes) being more voracious in permanent habitats, while invertebrates (e.g., odonate
naiads) are the most important in temporary ones; (5) tadpoles may play a regulatory effect
preying upon anuran eggs and recently hatched tadpoles (6) microhabitat use varies in
function of breeding habitat choice by adults, presence of predators, phylogeny, stage of
development and heterogeneity of the habitat; (7) historical factors restrict the breeding
habitats that species may use, and impose behavioral and physiologic constrains; (8) temporal
variation in biotic (e.g., risk factors) and abiotic factors (e.g., rainfall distribution), and the
reproductive patterns of the species may interfere in the structure of tropical tadpole
assemblages. Future efforts regarding the study of tadpoles should contemplate assemblages
associated with streams, and experimental studies. Temporal variation in the environmental
heterogeneity resulted in predictability of local tadpole assemblages. The environmental
component explained 23% of the variation in tadpole composition, while spatial parameters
explained the smaller portion of the variation (16%). A comparatively high portion of
temporal variation in the environmental heterogeneity was spatially structured (18%). The
proportion of litter and rocks on the stream bottom, depth, conductivity, and temperature were
correlated with tadpole composition. The gradient created by the proportion of litter and rocks
represented the changes from permanent and intermittent streams. This gradient provided the
species turnover, which also followed a gradient of conductivity, temperature, depth, and in a
lesser proportion, hydroperiod and width, all being strongly associated with permanence of
streams. The results also corroborate with both the environmental and the biotic control model
and indicate that temporal variation in environmental heterogeneity and the spatial position
are important to the structuring of local tadpole assemblages in the streams of REGUA. The
results also allowed to distinguish between tadpoles assemblages exclusive of permanent,
intermittent, and those inhabiting both streams. The results of this chapter are relevant to
understand in which extension the effects of temporal variation in environmental
heterogeneity and spatial processes affect the structure of tadpole assemblages, the most
fragile life stage of anurans
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Distribuição das assembleias de girinos associadas a riachos da Reserva Ecológica de Guapiaçu, Cachoeiras de Macacú, Rio de Janeiro, Brasil / Distribution of stream-dwelling tadpoles of the Reserva Ecológica de Guapiaçu, Cachoeiras de Macacú, Rio de Janeiro, BrazilVitor Nelson Teixeira Borges Júnior 22 January 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Os girinos são organismos diversos e abundantes nos pequenos riachos de cabeceira
de florestas tropicais e constituem importantes componentes da diversidade biológica, da
trófica e funcional dos sistemas aquáticos. Diferentes características estruturais e limnológicas
dos ambientes aquáticos influenciam a organização das assembleias de girinos. Embora o
estágio larvar dos anuros seja o mais vulnerável de seu ciclo de vida, sujeito a elevadas taxas
de mortalidade, as pesquisas sobre girinos na região neotropical ainda são pouco
representativas diante da elevada diversidade de anfíbios desta região e ferramentas que
permitam a sua identificação ainda são escassas. Nesta tese, dividida em três capítulos,
apresento uma compilação das informações relacionadas aos principais fatores que afetam as
assembleias de girinos na região tropical (Capítulo 1), a caracterização morfológica dos
girinos encontrados nos riachos durante o estudo e uma proposta de chave dicotômica de
identificação (Capítulo 2) e avalio a importância relativa da posição geográfica e da variação
temporal de fatores ambientais locais sobre as assembleias de girinos, assim como a
correlação entre as espécies de girinos e as variáveis ambientais de 10 riachos, ao longo de 15
meses, nas florestas da REGUA (Capítulo 3). Há pelo menos oito tendências relacionadas à
distribuição das assembleias de girinos: (1) o tamanho dos riachos e a diversidade de
microhabitats são importantes características abióticas influenciando a riqueza e a composição
de espécies; (2) em poças, o gradiente de permanência (e.g., hidroperíodo) e a
heterogeneidade do habitat são os principais fatores moldando as assembleias de girinos; (3) a
composição de espécies parece ser um parâmetro das assembleias mais relevante do que a
riqueza de espécies e deve ser primeiramente considerado durante o planejamento de ações
conservacionistas de anuros associados a poças e riachos; (4) a predação parece ser a
interação biótica mais importante na estruturação das assembleias de girinos, com predadores
vertebrados (e.g. peixes) sendo mais vorazes em habitats permanentes e predadores
invertebrados (e.g. larvas de odonata) sendo mais vorazes em ambientes temporários; (5) os
girinos podem exercer um efeito regulatório, predando ovos e girinos recém eclodidos; (6) o
uso do microhabitat varia em função da escolha do habitat reprodutivo pelos adultos, presença
de predadores, filogenia, estágio de desenvolvimento e heterogeneidade do habitat; (7) os
fatores históricos restringem os habitats reprodutivos que uma espécie utiliza, impondo
restrições comportamentais e fisiológicas; (8) a variação temporal nos fatores bióticos (e.g.,
fatores de risco), abióticos (e.g., distribuição de chuvas), e no padrão de reprodução das
espécies pode interferir na estrutura das assembleias de girinos tropicais. A variação temporal
na heterogeneidade ambiental dos riachos da REGUA resultou na previsibilidade das
assembleias locais de girinos, sendo que os parâmetros ambientais explicaram 23% da
variação na sua composição. Os parâmetros espaciais explicaram uma porção menor da
variação nas assembleias (16%), enquanto uma porção relativamente elevada da variação
temporal da heterogeneidade ambiental foi espacialmente estruturada (18%). As variáveis
abióticas que apresentaram as maiores correlação com a composição das assembleias de
girinos foram a proporção de folhiço e de rochas no fundo do riacho, e secundariamente a
profundidade, a condutividade e a temperatura. O gradiente gerado pela proporção de folhiço
e de rochas representou a transição entre riachos permanentes e intermitentes. Este gradiente
proporcionou o turnover de espécies, o qual também seguiu um gradiente de condutividade,
temperatura, profundidade, e em menor extensão, de hidroperíodo e largura, que estiveram
fortemente associado ao grau de permanência dos riachos. Estes resultados corroboram tanto
a hipótese do controle ambiental, como do controle biótico de comunidades e indicam que a
variação temporal da heterogeneidade ambiental e a variação na posição geográfica são
importantes para a estruturação local de assembleias de girinos da REGUA. Os resultados
também permitiram distinguir entre assembleias de girinos exclusivas de riachos
permanentes, exclusivas de riachos intermitentes e aquelas registradas nos dois tipos de
riachos. Os resultados deste capítulo são relevantes para compreender em que extensão os
efeitos da variação temporal na heterogeneidade ambiental e de processos espaciais afetam
localmente a estruturação de assembleias de girinos. / Tadpoles are diverse and abundant organisms in headwater streams of tropical
rainforests and constitute important components of biological, trophic and functional
diversity. Furthermore, different structural (e.g. size, depth, microhabitat availability) and
limnological (e.g. conductivity, temperature) characteristics affect tadpole organization.
Although the larval stage is the most vulnerable in anurans, subject to high mortality rates,
researches on tadpoles in the neotropics, as tools for their identification, remain scarce face
the high diversity of anurans found in this region. In this thesis, I present a compilation of
information on the main factors affecting tadpole assemblages in the tropics (Chapter 1), the
morphological characterization of tadpoles found in streams during the study with a propose
of dichotomous key of identification (Chapter 2), and evaluated the relative importance of
geographical position and the temporal variation o local environmental factors on tadpole
assemblages through 15 months in 10 small streams in the Atlantic Forest of Reserva
Ecológica do Guapiaçu (REGUA), municipality of Cachoeiras de Macacú, Rio de Janeiro,
Brazil. I also investigated the correlation between tadpoles and the environmental variables of
streams (Chapter 3). We can recognize at least eigth major trends regarding the distribution
and structure of tropical tadpole assemblages: (1) stream size and microhabitat diversity are
important abiotic features influencing species richness and composition; (2) in ponds, the
permanence gradient (e.g., hydroperiod), and the heterogeneity of habitat are the main factors
modeling tropical tadpole assemblages; (3) species composition seems to be a more relevant
assemblage parameter than species richness and should be first considered when planning
conservation of both pond and stream-dwelling anurans; (4) predation seems to be the most
important biotic interaction structuring tropical tadpole assemblages, with vertebrate predators
(e.g., fishes) being more voracious in permanent habitats, while invertebrates (e.g., odonate
naiads) are the most important in temporary ones; (5) tadpoles may play a regulatory effect
preying upon anuran eggs and recently hatched tadpoles (6) microhabitat use varies in
function of breeding habitat choice by adults, presence of predators, phylogeny, stage of
development and heterogeneity of the habitat; (7) historical factors restrict the breeding
habitats that species may use, and impose behavioral and physiologic constrains; (8) temporal
variation in biotic (e.g., risk factors) and abiotic factors (e.g., rainfall distribution), and the
reproductive patterns of the species may interfere in the structure of tropical tadpole
assemblages. Future efforts regarding the study of tadpoles should contemplate assemblages
associated with streams, and experimental studies. Temporal variation in the environmental
heterogeneity resulted in predictability of local tadpole assemblages. The environmental
component explained 23% of the variation in tadpole composition, while spatial parameters
explained the smaller portion of the variation (16%). A comparatively high portion of
temporal variation in the environmental heterogeneity was spatially structured (18%). The
proportion of litter and rocks on the stream bottom, depth, conductivity, and temperature were
correlated with tadpole composition. The gradient created by the proportion of litter and rocks
represented the changes from permanent and intermittent streams. This gradient provided the
species turnover, which also followed a gradient of conductivity, temperature, depth, and in a
lesser proportion, hydroperiod and width, all being strongly associated with permanence of
streams. The results also corroborate with both the environmental and the biotic control model
and indicate that temporal variation in environmental heterogeneity and the spatial position
are important to the structuring of local tadpole assemblages in the streams of REGUA. The
results also allowed to distinguish between tadpoles assemblages exclusive of permanent,
intermittent, and those inhabiting both streams. The results of this chapter are relevant to
understand in which extension the effects of temporal variation in environmental
heterogeneity and spatial processes affect the structure of tadpole assemblages, the most
fragile life stage of anurans
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Conservation Biology in Poorly Studied Freshwater Ecosystems: From Accelerated Identification of Water Quality Bioindicators to Conservation PlanningAl-Saffar, Mohammed Abdullah 08 March 2016 (has links)
No description available.
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Mountains as crossroads : temporal and spatial patterns of high elevation activity in the Greater Yellowstone ecosystem, USAReckin, Rachel Jean January 2018 (has links)
In the archaeological literature, mountains are often portrayed as the boundaries between inhabited spaces. Yet occupying high elevations may have been an adaptive choice for ancient peoples, as rapidly changing elevations also offer variation in climate and resources over a relatively small area. So what happens, instead, if we put mountain landscapes at the center of our analyses of prehistoric seasonal rounds and ecological adaptation? This Ph.D. argues that, in order to understand any landscape that includes mountains, from the Alps to the Andes, one must include the ecology and archaeology of the highest elevations. Specifically, I base my findings on new fieldwork and lithic collections from the Absaroka and Beartooth Mountains in the Greater Yellowstone Ecosystem (GYE) of the Rocky Mountains, which was a vital crossroads of prehistoric cultures for more than 11,000 years. I include five interlocking analyses. First, I consider the impacts of anthropogenic climate change on high elevation cultural resources, focusing on the diminishing resiliency of ancient high elevation ice patches and the loss of the organic artifacts and paleobiological materials they contain. Second, I create a dichotomous key for chronologically typing projectile points, suggesting a methodological improvement for typological dating in the GYE and for surface archaeology more broadly. Third, I use obsidian source data to consider whether mountain people were a single, unified group or were represented by a variety of peoples with different zones of land tenure. Fourth, I consider high elevation occupation in both mountain ranges as part of the seasonal round, using indices of diversity in tool types and raw material to study how the duration of those occupations changed through time. And, finally, I test the common contention that ancient people primarily used mountains as refugia from extreme climatic pressure at lower elevations. Ultimately, I find that, in both mountain ranges, increased high elevation activity is most highly correlated with increased population, not with hot, dry climatic conditions. In other words, the mountains were more than simply refugia for plains or basin people to occupy when pressured by climatic hardship. In addition, between the Absarokas and the Beartooths the evidence suggests two different patterns of occupation, not a monolithic pan-mountain adaptation. These results demonstrate the potential contributions of surface archaeology to our understanding of prehistory, and have important implications for the way we think about mountain landscapes as peopled spaces in relation to adjacent lower-elevation areas.
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