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2.
Glob Chang Biol ; 22(6): 2003-12, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26663738

RESUMO

Land use changes have profound effects on populations of Neotropical primates, and ongoing climate change is expected to aggravate this scenario. The titi monkeys from eastern Brazil (Callicebus personatus group) have been particularly affected by this process, with four of the five species now allocated to threatened conservation status categories. Here, we estimate the changes in the distribution of these titi monkeys caused by changes in both climate and land use. We also use demographic-based, functional landscape metrics to assess the magnitude of the change in landscape conditions for the distribution predicted for each species. We built species distribution models (SDMs) based on maximum entropy for current and future conditions (2070), allowing for different global circulation models and contrasting scenarios of glasshouse gas concentrations. We refined the SDMs using a high-resolution map of habitat remnants. We then calculated habitat availability and connectivity based on home-range size and the dispersal limitations of the individual, in the context of a predicted loss of 10% of forest cover in the future. The landscape configuration is predicted to be degraded for all species, regardless of the climatic settings. This include reductions in the total cover of forest remnants, patch size and functional connectivity. As the landscape configuration should deteriorate severely in the future for all species, the prevention of further loss of populations will only be achieved through habitat restoration and reconnection to counteract the negative effects for these and several other co-occurring species.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Haplorrinos , Animais , Brasil , Previsões , Florestas , Modelos Biológicos
3.
Plants (Basel) ; 13(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39065415

RESUMO

Understanding the ecological and evolutionary aspects of mutualistic interactions is essential for predicting species responses to environmental changes. This study aimed to investigate the phenological patterns and reproductive strategies in two closely related fig tree species, Ficus citrifolia and Ficus eximia. We monitored 99 F. citrifolia and 21 F. eximia trees weekly from January 2006 to April 2011 in an area close to the southern edge of the tropical region in Brazil. Our results revealed contrasting phenological patterns between the two species, with F. citrifolia displaying an annual flowering pattern (1.4 episodes per tree per year) and F. eximia a supra-annual pattern (0.5 episodes per tree per year). We also found significant differences in reproductive strategies, with F. eximia producing more pistillate flowers and, consequently, more seeds and pollinating wasps per fig than F. citrifolia, likely as an adaptation to overcome limitations of low population density by maximizing the gene flow. As the shorter-lived organism, the fig wasp was found to influence critical processes associated with the success and stability of mutualism, such as fig development and ripening. Our findings emphasize the importance of understanding the intricate interactions between mutualistic partners and their adaptive responses to environmental conditions in shaping fig tree populations' reproductive strategies and genetic structure.

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