Sex in crocodilians is not determined by chromosomes, but by egg incubation temperature, where different temperatures produce different clutch sex ratios. Two patterns have been proposed to describe these changes in sex ratios: a 100% female proportion at low and high temperatures with male predominance at intermediate ones (FMF) or a simpler pattern with a single female-to-male transition (FM). Over the last three decades, researchers have provided empirical information to support either of these two patterns in different species; however, no consensus has been reached partly because data have not been analysed as a whole.
View Article and Find Full Text PDFTwo main theories have attempted to explain variation in plant species composition (β-diversity). Niche theory proposes that most of the variation is related to environment (environmental filtering), whereas neutral theory posits that dispersal limitation is the main driver of β-diversity. In this study, we first explored how α- and β-diversity of plant functional groups defined by growth form (trees, shrubs and lianas, which represent different strategies of resource partitioning), and dispersal syndrome (autochory, anemochory and zoochory, which represent differences in dispersal limitation) vary with successional age and topographic position in a tropical dry forest.
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