Shifts to multiple optima underlie climatic niche evolution in New World phyllostomid bats

Abstract

Climate underlies species distribution patterns, especially in species where climate limits distributions, such as the phyllostomid bats, which are mostly restricted to the New World tropics. The evolutionary dynamics that shaped phyllostomid climatic niches remain unclear, and a broad phylogenetic perspective is required to uncover their patterns. We used geographical distributions and evolutionary relationships of 130 species, climate data and phylogenetic comparative methods to uncover dynamics of phyllostomid climatic niche evolution. Diversification of climatic niches began early in phyllostomid evolution (~34 Mya), with most changes taking place ~20 Mya. Although most of these bats were found in tropical regions, shifts towards different evolutionary optima were common. Shifts were mostly towards temperate climates, reflecting complexities in phyllostomid evolution highlighted by the probable role of species-specific adaptations to cope with these climates, the influence of palaeoclimatic events, and biogeographical effects related to the evolution and dispersal of clades in the New World. Our results broaden our understanding of the relationships between phyllostomid bats and climate, filling an important gap in knowledge and suggesting a complex evolution in their occupation of the climatic niche space.

Strong but opposing effects of climatic niche breadth and dispersal ability shape bat geographical range sizes across phylogenetic scales

“…Climate is an important abiotic factor that regulates phyllostomid distribution, as they have a tropical origin and are mainly adapted to the climatic conditions found at low latitudes, in accordance with the expectations of the tropical niche conservatism hypothesis (Stevens, 2006(Stevens, , 2011Varzinczak, Moura, & Passos, 2019;Villalobos, Rangel, & Diniz-Filho, 2013; but also see Ramos-Pereira & Palmeirim, 2013). In fact, few phyllostomids have climatic niches that include extra-tropical areas due to metabolic and dietary constraints that limit them to expand their distributions towards temperate, cooler and drier environments (Stevens, 2004;Varzinczak et al, 2019). Moreover, although flight distinguishes bats from other mammals by reducing limitations to their dispersal…”

“…Accordingly, our analytical framework was conceived by explicitly considering phylogenetic information on phyllostomid evolutionary relationships and divergence times from a time-calibrated phylogeny (Shi & Rabosky, 2015). This phylogenetic hypothesis was built from a combined set of several mitochondrial and nuclear nucleotide sequences, which present strong node support and a high correlation with previous hypotheses of evolutionary relationships among bats (Shi & Rabosky, 2015;Varzinczak et al, 2019). We pruned this phylogeny to match the 74 phyllostomid species present in our database.…”

“…Phyllostomids radiated mainly in the tropics (Tavares, Dávalos, Warsi, Balseiro, & Mancina, 2018); their climatic niches are tightly related to tropical climates (Stevens, 2006;Varzinczak et al, 2019). Therefore, as are many other tropical clades, phyllostomids are adapted to a narrow range of climatic conditions (Stevens, 2004(Stevens, , 2006Wiens & Donoghue, 2004).…”

“…Therefore, as are many other tropical clades, phyllostomids are adapted to a narrow range of climatic conditions (Stevens, 2004(Stevens, , 2006Wiens & Donoghue, 2004). Furthermore, metabolic and energetic constraints, a plant-based diet for most species, and a high dependence upon the vegetation structure and resources found in the tropics, prevented phyllostomids from expanding their geographical distributions towards the temperate climates at high latitudes outside the tropics (Alroy, 2019;Stevens, 2004;Varzinczak et al, 2019). The New World spans a broad latitudinal extent, and variations in climatic conditions at broad geographical scales impose filters on phyllostomid distributions (Stevens, 2004;Varzinczak et al, 2019;Villalobos et al, 2013).…”

Understanding the relationship between climatic niches and dispersal through the lens of bat wing morphology

“…Most phyllostomids have their distributions tightly linked with tropical-forested sites which are predominantly found at low latitudes. Phyllostomids depend on the tropical climate due to their tropical origins and metabolic constraints (Stevens, 2004(Stevens, , 2006Varzinczak et al, 2019); they also have an increased dependence of forested habitats, since most species are phytophagous (Stevens, 2004;Monteiro & Nogueira, 2011). However, forested habitats pose several challenges for flying species, since these environments can be highly cluttered; flying forest dwellers often have wing adaptations suited to perform energetically efficient flight (Findley, 1972;Swaddle & Witter, 1998;Jennings et al, 2004).…”