Loading...
Publication
Variabilidade morfológica do esgana-gata (Gasterosteus aculeatus L.) ao longo da sua área de distribuição global
Authors
Advisor(s)
Abstract(s)
O esgana-gata é uma espécie cuja distribuição global que ocorre ao longo do hemisfério norte.
Tornou-se numa excelente espécie modelo para vários estudos por possuir grande variação na utilização de recursos e a nível morfológico dentro das mesmas populações e entre populações.
O esgana-gata é uma espécies que evolui rapidamente e por isso é de esperar que as populações destes organismos respondam rapidamente às alterações climáticas. O estudo da sua morfologia poderá ser um fator essencial para a sua conservação no sentido de entender como estas espécies estão a responder às alterações no seus habitas. Analisámos as variações morfológicas de populações de esgana-gata de vários lagos em 4 países distintos, Escócia, Islândia, Canadá e Alasca, que apresentam características ambientais diferentes com o intuito de entender qual o grau de variabilidade morfológica do esgana-gata ao longo da sua área de distribuição e se esta é maior a nível regional (entre países), ou local (entre os lagos). Analisou-se um total de 2763 indivíduos relativamente à forma do corpo e analisaram-se 9 variáveis morfométricas para os mesmos indivíduos. Identificaram-se dois tipos morfológicos pertencentes ao continente americano e ao continente europeu. Encontraram-se mais diferenças relacionadas com a morfometria dos indivíduos do que relacionas com a sua forma do corpo sobretudo entre países. Em termos de análises entre lagos, dentro de cada país, verificou-se uma grande variabilidade das variáveis complementares e praticamente não se obteve diferenças relativas à forma do corpo. Deste modo, os nossos resultados sugerem que a forma global do corpo de esgana-gata poderá estar a responder de forma mais acentuada a variações de larga escala, ao longo da sua distribuição e menos às características especificas do habitat.
Three-spined Stickleback is a species whose global distribution occurs throughout the northern hemisphere. It has become an excellent model species for several studies as it has great variation in resource use and morphology within and between populations. The stickleback is a species that evolves quickly and therefore it is expected that populations of these organisms respond quickly to climate change. The study of their morphology can be an essential factor for their conservation in the sense of how these species are responding to changes in their habitats. We analyzed the morphological variations of stickleback populations from several lakes in 4 different countries, Scotland, Iceland, Canada and Alaska, which have different environmental characteristics in order to sense the degree of morphological variability of the stickleback throughout its distribution area and whether this is the highest regional (among countries) or local (among lakes) level. A total of 2,763 were analyzed regarding body shape and 9 morphometric variables were analyzed for the same individuals. Two morphological types belonging to the American continent and the European continent were identified. More differences were found related to the morphometry of the necessary than related to their body shape, especially between countries. In terms of analyzes between lakes, within each country, there was great variability in the complementary variables and practically no difference was obtained regarding the shape of the body. Thus, our results obtained that an overall shape of the stickleback body may be responding more strongly to large-scale variations, along its distribution and less to the specific characteristics of the habitat.
Three-spined Stickleback is a species whose global distribution occurs throughout the northern hemisphere. It has become an excellent model species for several studies as it has great variation in resource use and morphology within and between populations. The stickleback is a species that evolves quickly and therefore it is expected that populations of these organisms respond quickly to climate change. The study of their morphology can be an essential factor for their conservation in the sense of how these species are responding to changes in their habitats. We analyzed the morphological variations of stickleback populations from several lakes in 4 different countries, Scotland, Iceland, Canada and Alaska, which have different environmental characteristics in order to sense the degree of morphological variability of the stickleback throughout its distribution area and whether this is the highest regional (among countries) or local (among lakes) level. A total of 2,763 were analyzed regarding body shape and 9 morphometric variables were analyzed for the same individuals. Two morphological types belonging to the American continent and the European continent were identified. More differences were found related to the morphometry of the necessary than related to their body shape, especially between countries. In terms of analyzes between lakes, within each country, there was great variability in the complementary variables and practically no difference was obtained regarding the shape of the body. Thus, our results obtained that an overall shape of the stickleback body may be responding more strongly to large-scale variations, along its distribution and less to the specific characteristics of the habitat.
Description
Dissertação de Mestrado apresentada no ISPA – Instituto Universitário para obtenção de grau de Mestre na especialidade de Biologia Marinha e Conservação
Keywords
Gasterosteus aculeatus Morfologia Ambiente Morphology Environment