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Ecological traits underlying interspecific variation in climate matching of birdsViana, Duarte S., Chase, Jonathan M. 23 August 2023 (has links)
Aim: The abundances and distributions of some species are more closely matched to variations in climate than others. Species traits that might influence how well the distribution and abundance of a species are matched to climatic variation include life history (e.g., body size and dispersal ability), ecology (e.g., habitat specialization and territoriality) and demography (e.g., population size). Here, we used a survey of bird abundances across the USA to assess the extent to which species abundances and distributions are predicted by climate (i.e., climate matching) and how species traits
relate to interspecific variation in climate matching.
Location: USA.
Time period: 1983–2018.
Major taxa studied: Birds.
Methods: Species abundances were obtained from the North American Breeding Bird Survey. Climate matching was estimated as the predictive performance of species–climate models fitted using boosted regression trees and generalized additive models and modelled as a function of species traits.
Results: Species traits explained 56% of the variation in climate matching among species. Intermediate-sized species were more well matched to climate than smaller or
larger species, as were species that lived primarily in forested compared with open habitats, species that were locally more abundant and species that were more territorial.
Alternatively, species that were more specialized or had high variability in abundance among sites were less well matched to climate. We also found that species classified as “near threatened” were more well matched to climate, suggesting that these species might be more vulnerable to climate change. However, species classified as “vulnerable” were more decoupled from climate than those of “least concern”, possibly owing to ecological drift associated with progressive population declines. Main conclusions: Our findings provide an ecological basis for understanding the extent to which species abundances and distributions match broad climatic gradients, which can provide the groundwork to improve our ability to predict distributions under global change.
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Padrões espaciais e temporais na amplitude de nicho climático de vertebrados terrestres / Spatial and temporal patterns in niche breadth of terrestrial vertebratesSilva, Helen Rosa da 26 March 2015 (has links)
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Previous issue date: 2015-03-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Understanding how species are distributed across space and what determines where they
live is one of the oldest goals in Ecology. The concept of niche is very closely related to
this goal. In fact, environmental variables are frequently used to predict the potential
distribution of species. Niche amplitude is an important concept which helps us to
understand which part of the available environmental space each species occupies, and
how much of their niches overlap. Here we used a measure of niche amplitude based on
the minimum and maximum tolerances of terrestrial vertebrates (except reptiles) for
each variable related to climate. We calculated a single measure of niche amplitude for
each species by considering together all chosen environmental variables. We used this
number to first investigate the presence of latitudinal gradient in niche amplitude across
the study area, which comprised the whole terrestrial globe. There is a significant
correlation between niche amplitude and latitude for Old World birds. Second we tried
to identify some phylogenetic structure in niche amplitude for birds. For this goal, we
calculated the pair-wise niche overlap, and then compared the degree of overlap with
pair-wise phylogenetic distances. We found no relationship between niche overlap and
phylogenetic distance. We conclude that the absence of phylogenetic signal in niche
overlap is due to the high dispersion capability of birds in general. If species have a high
geographic range, they consequently have high niche amplitude, and therefore high
overlap rates. Finally, we found a clear tendency of positive local spatial
autocorrelation in mean niche overlap, as neighbor cells tend to show similar rates of
niche overlap between species. / Compreender os fatores que determinam a distribuição das espécies no espaço
geográfico é uma das questões mais importantes em ecologia. O conceito de nicho é
fortemente relacionado a essa questão. Não por acaso, variáveis ambientais são
comumente usadas para inferir a distribuição potencial de espécies. Amplitude de nicho
é uma medida importante que nos possibilita saber que proporção do espaço ambiental
cada espécie ocupa. Assim, podemos também identificar que proporção do espaço
ocupado por cada espécie, seu nicho, é sobreposta pelo nicho das espécies coexistentes.
No presente trabalho utilizamos uma medida de amplitude de nicho específica baseada
na soma das tolerâncias para cada variável climática utilizada. Utilizamos essa medida
para investigar, primeiramente, a presença de estrutura espacial, especificamente
gradiente latitudinal, na amplitude de nicho de vertebrados terrestres (exceto répteis),
numa escala global. Apenas aves do Velho Mundo apresentaram amplitude de nicho
negativamente associada à latitude. Posteriormente, investigamos a presença de
estrutura filogenética na amplitude de nicho em Aves, baseados na hipótese de
conservação de nicho. Para esse objetivo calculamos a sobreposição de nicho par-a-par
e então correlacionamos essa medida com as distâncias filogenéticas. Não houve
correlação entre proximidade filogenética e sobreposição de nicho. Tal resultado pode
estar relacionado à grande capacidade de dispersão de aves. Se a área de ocupação
geográfica é ampla, a amplitude das tolerâncias é em geral alta e consequentemente a
sobreposição média entre diferentes espécies. Finalmente houve forte indício de
autocorrelação espacial positiva na sobreposição média por célula entre células
próximas, indicando que áreas próximas tendem a apresentar espécies com taxas
semelhantes de sobreposição de nicho.
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Reproductive modes are associated to climatic niche evolution in treefrogs (anura: hylidae)Gurgel, Priscila Cabral Silveira 29 February 2016 (has links)
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Previous issue date: 2016-02-29 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The similarity of life-history traits among closely related species is a well-known pattern in
evolutionary biology. Thus, closely related species tend to be more akin to each other than to
distantly related ones. The propensity of closely related species to conserve climatic niche
features over macroevolutionary time can be defined as climatic niche conservatism. Recent
studies have shown the importance of environmental variables with regards to the diversity
and distribution of anurans with differences in their reproductive traits under an evolutionary
perspective. In this work, using frog species in the Hylidae family, we tested the hypothesis
that species more independent from main bodies of water for reproduction are restricted to
areas with higher temperature and precipitation means. We also investigated the evolution of
climatic niche features of species with different degrees of dependence on water for
reproduction. Our results corroborate the first hypothesis and show that terrestrial egg-laying
species, in the Hylinae subfamily, have more conserved climatic niche position when
compared to Hylinae species that deposits their eggs and tadpoles in main water bodies. Thus,
we suggest that reproductive modes are associated with variation in the evolution of climatic
niches of frogs. / A similaridade entre atributos de espécies aparentadas é um padrão tradicional reconhecido
em biologia evolutiva. Espécies aparentadas tendem ser mais similares entre si do que com
espécies não aparentadas. A tendência de espécies aparentadas conservar as características de seu nicho ao longo do tempo macroevolutivo pode ser definido como conservação
filogenética de nicho. Estudos recentes tem mostrado a importância das variáveis climáticas
na distribuição de anfíbios anuros com diferentes modos reprodutivos utilizando uma
abordagem evolutiva. Neste trabalho, usando as espécies de pererecas da família Hylidae,
testamos a hipótese de que espécies menos dependentes dos corpos d'água para reprodução
ocorrem em áreas mais quentes e mais úmidas. Além disso, investigamos como foi a evolução
dos atributos do nicho climático (posição e amplitude) de espécies, da subfamília Hylinae,
com diferentes níveis de dependência dos corpos d'água para reprodução. Nossos resultados
corroboram a primeira hipótese e mostram que, espécies da subfamília Hylinae que depositam
seus ovos fora da água estão restritas a lugares mais quentes e mais úmidos. Além disso, tais
espécies tem o nicho climático mais conservado do que espécies que depositam tanto ovos
como girinos em corpos d'água principais. Portanto, sugerimos que os diferentes modos
reprodutivos refletem em diferenças na evolução do nicho climático nas espécies da
subfamília Hylinae.
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Phylogeny, biogeography, and breeding system evolution in Moraceae / Phylogénie, biogéographie et évolution des systèmes sexuels chez les MoraceaeZhang, Qian 16 July 2019 (has links)
Les Angiospermes sont le clade le plus diversifié des plantes actuelles et sont exceptionnellement riches en espèces dans les régions tropicales. Dans cette thèse, j’ai étudié l’évolution des systèmes sexuels et l’histoire biogéographique de la famille des Moraceae, clade modèle utilisé pour comprendre l’origine et l’évolution de la diversité chez les Angiospermes. Dans le Chapitre I, j’ai reconstruit et calibré un nouvel arbre phylogénétique daté pour les Moraceae. J’ai ensuite utilisé cet arbre pour reconstruire les états ancestraux des systèmes sexuels chez les Moraceae et Ficus. Les âges des groupes-couronne des Moraceae et du genre Ficus sont estimés au Crétacé et à l’Eocène, respectivement. La dioécie est inférée comme l’état ancestral des systèmes sexuels chez les Moraceae, avec plusieurs transitions ultérieures vers la monoécie, y compris chez Ficus. Ce résultat suggère que la dioécie ne représente pas nécessairement un cul-de-sac évolutif. Dans le Chapitre II, j’ai reconstruit un arbre phylogénétique daté pour la tribu des Dorstenieae, distribuée principalement dans les régions tropicales, à partir d’un nouveau jeu de données génomiques nucléaires produit avec une approche Hyb-Seq. L’histoire biogéographique du groupe a ensuite été reconstruite en utilisant les modèles de dispersion-extinction-cladogenèse. Les âges des groupes-couronne des Dorstenieae et du genre Dorstenia sont estimés au Crétacé et dans la période du Crétacé au Paléocène, respectivement. Deux évènements de dispersion à longue distance depuis l’Afrique continentale vers l’Amérique du Sud ont eu lieu au Cénozoïque (Dorstenia et Brosimum s.l.). Dans le Chapitre III, j’ai testé les différences de niche climatique (température et précipitation) entre les deux systèmes sexuels (monoécie et gynodioécie) chez Ficus avec un nouveau jeu de données fiables d’occurrences spatiales et de systèmes sexuels chez 183 espèces. À cette fin, j’ai utilisé deux approches comparatives : équations d’estimation généralisées (GEE) et modèles linéaires généralisés (GLM). Une relation positive entre précipitation et gynodioécie est soutenue par les analyses GLM, et aucune méthode ne soutient une relation entre température et système sexuel. Une meilleure capacité à se disperser et le potentiel d’autopollinisation sont deux explications possibles pour la colonisation et la survie des espèces monoïques dans des environnements plus secs. Cette thèse démontre le potentiel des méthodes phylogénétiques comparatives et des données phylogénomiques pour répondre aux questions d’évolution des systèmes sexuels et de biogéographie chez les Moraceae et ouvre plusieurs nouvelles perspectives importantes méritant d’être approfondies chez d’autres clades de plantes, telles que la relation entre système sexuel et niche climatique. / Angiosperms are the most diversified clade of extant plants and are exceptionally species-rich in tropical regions. In this thesis, I investigated breeding system evolution and biogeographic history in the family Moraceae, which I used as a model clade to understand the origin and evolution of diversity of angiosperms. In Chapter I, I reconstructed and calibrated a new dated phylogenetic tree for Moraceae as a whole. I then used this tree to reconstruct ancestral states of breeding systems in Moraceae and Ficus. The crown group ages of Moraceae and Ficus were estimated in the Cretaceous and in the Eocene, respectively. Dioecy was inferred as the ancestral breeding systems of Moraceae, with several subsequent transitions to monoecy, including in Ficus. This result suggests that dioecy is not necessarily an evolutionary dead end. In Chapter II, I reconstructed a dated phylogenetic tree for tribe Dorstenieae, mainly distributed in tropical regions, with a new data set of nuclear genomic data generated with a Hyb-Seq approach. Biogeographic history was then reconstructed using dispersal-extinction-cladogenesis models. The crown group ages of Dorstenieae and Dorstenia were estimated in the Cretaceous and in the Cretaceous/Paleocene period, respectively. Two long-distance dispersal events from continental Africa to South America occurred in the Cenozoic (Dorstenia and Brosimum s.l.). In Chapter III, I tested the climatic niche difference (temperature and precipitation) between the two breeding systems (monoecy and gynodioecy) in Ficus using a new dataset of cleaned spatial occurrence records and breeding systems for 183 species. I used two comparative approaches: generalized estimating equations (GEE) and generalized linear models (GLM). A positive relationship between precipitation and gynodioecy was supported by GLM, but not GEE analyses, and no relationship between temperature and breeding systems was supported by either method. Higher dispersal ability and the potential for self-fertilization may explain why monoecious species of Ficus have been able to colonize and survive in drier environments. This thesis highlights the potential of phylogenetic comparative methods and phylogenomic data to address questions of breeding system evolution and biogeography in Moraceae, and opens up several important new perspectives worth investigating in other plant clades, such as a relationship between breeding system and climatic niche.
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