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Previous issue date: 2012-07-05 / How ecologically similar species are able to coexist has always generated great interest in the
scientific community. Classical niche theory predicts that species coexistence is only possible
when they segregate in at least one dimension of the ecological niche, thus leading to
ecological differentiation among species. However, recent work has shown that species that
are more similar in some ecological traits are the ones more prone to be able to coexist
(environmental filter). The knowledge of how these forces act shaping ecological
communities can reveal co-existence strategies, providing important information for
management and conservation of the species. This study tested these hypotheses using a pair
of coexisting species of Herpsilochmus, H. pectoralis and H. sellowi. In this study I use high
resolution (50 x 50 m) ecological niche models to Identify which environmental factors best
predict species occurrence. Next, I calculate the overlap in habitat use by species and build
null models to test the hypothesis of spatial niche segregation. In addition, I obtain the
selectivity parameters of habitat use to test whether the species H. pectoralis (larger body
size) is less selective than H. sellowi (smaller body size) as stated in the literature for other
species. The results reject the ecological equivalence among species, revealing that the
species of Herpsilochmus explore the habitat differently, having different environmental
niches. The hypothesis of environmental filter was not observed in my analysis, the observed
overlap in habitat use among species was lower than expected by chance. Evidence that
Herpsilochmus are spatially segregating reinforces the hypothesis of interspecific competition
as the predominant force in the selection of microhabitat of the species. However, more data
and experiments are necessary to state categorically that the observed pattern is a result of
current or past competition / Como esp?cies similares ecologicamente s?o capazes de coexistir sempre gerou grande
interesse na comunidade cient?fica. A teoria cl?ssica de nicho prev? que para que a
coexist?ncia seja poss?vel as esp?cies devem segregar em alguma dimens?o do nicho
ecol?gico, portanto levando a diferencia??o entre as esp?cies. No entanto, trabalhos recentes
tem demonstrado que justamente esp?cies mais similares em algumas caracter?sticas
ecol?gicas seriam mais capazes de coexistir (filtro ambiental). O conhecimento de como
essas for?as atuam nas comunidades pode revelar estrat?gias de coexist?ncia, trazendo
importantes informa??es para o manejo e conserva??o das esp?cies. Neste estudo testei essas
hip?teses de coexist?ncia utilizando o par de esp?cies Herpsilochmus pectoralis e H. sellowi.
Para isso utilizei modelos de nicho ecol?gico em alta resolu??o (50 x50 m).Identifiquei quais
os fatores ambientais estudados melhor predizem a ocorr?ncia das esp?cies. Em seguida,
calculei a sobreposi??o no uso de h?bitat pelas esp?cies e constru? modelos nulos para testar a
hip?tese de segrega??o de nicho espacial. Ainda, calculei par?metros de seletividade do uso
do h?bitat para testar se a esp?cie H. pectoralis (esp?cie de maior tamanho de corpo) ? menos
seletiva que o H. sellowi (esp?cie de menor tamanho de corpo) como previsto na literatura
para outras esp?cies.Os resultados rejeitam a equival?ncia ecol?gica entre as esp?cies,
revelando que as esp?cies de Herpsilochmus exploram o habitat de forma diferenciada,
possuindo nichos ambientais distintos. A hip?tese de filtro ambiental n?o foi evidenciada em
nossas an?lises, sendo a sobreposi??o no uso do h?bitat observada entre as esp?cies menor do
que o esperado ao acaso. Evid?ncias de que os Herpsilochmus est?o segregando
espacialmente refor?a a hip?tese da competi??o interespec?fica como for?a predominante na
sele??o de microh?bitat das esp?cies. No entanto, para afirmar categoricamente que o padr?o
observado ? efeito de uma competi??o atual ou passada experimentos futuros s?o sugeridos
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/14041 |
| Date | 05 July 2012 |
| Creators | Fran?a, Karol Lyncoln B. de O. de |
| Contributors | CPF:90773306153, http://lattes.cnpq.br/2151112850152895, Souza, Alexandre Fadigas de, CPF:02845395701, http://lattes.cnpq.br/7844758818522706, Pichorim, Mauro, CPF:50373625987, http://lattes.cnpq.br/5696697654544552, Marini, Miguel ?ngelo, CPF:33396205120, http://lattes.cnpq.br/7912919431438847, Costa, Gabriel Corr?a |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Ecologia, UFRN, BR, Bioecologia Aqu?tica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/embargoedAccess |
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