On the association between environmental gradients and skull size variation in the great fruit-eating bat, Artibeus lituratus (Chiroptera: Phyllostomidae)

Abstract

Understanding the spatial distribution of phenotypes and their association with local environmental conditions can provide important insights into the evolutionary history and ecological dynamics of species. Geographical variation in the skull size of the Artibeus lituratus complex was explored to evaluate the association between morphological traits and habitat-specific environmental conditions in the mainland populations of Middle and South America. We performed a principal component analysis based on 390 museum specimens using 17 cranial and mandibular measurements to explore the overall morphometric variation in our sample. Additionally, we used the information from 19 bioclimatic variables from 127 collecting localities to assess the extent of variation in environmental space across our study area. A canonical correlation analysis performed to evaluate the association between morphological and environmental variables indicated a high correlation between morphology and environment. Seasonality was correlated with skull size (canonical r = 0.7). Specifically, skull size in the A. lituratus complex increases as the amount of precipitation during the driest season increases and as inter-annual precipitation variability decreases. This result supports the hypothesis that environmental pressures are at least partially responsible for the skull size differences observed. Moreover, the nonrandom distribution of individuals with different skull sizes suggests that environmental filtering plays a role in determining the geographical distribution of morphological variants.

Cranial variation of the greater horseshoe bat Rhinolophus ferrumequinum (Chiroptera: Rhinolophidae) from the central Balkans

“…Thus, bats living in such environments are more likely to be smaller . Additionally, Burnett (1983) found that precipitation had a greater influence on wing and skull size of E. fuscus than did the temperature, while Marchán-Rivadeneira et al (2012) reported that skull size in A. lituratus increased as the amount of precipitation during the driest season increased. On the other hand, we found that four climatic factors related to temperature have statistically significant effects on the skull size variation.…”

“…Thus, genetic differentiation and differences in genetic variability between isolated populations probably reflect the species' colonization history and also point to reduced gene flow over greater distances (Rossiter et al, 2006). Study of association of phenotype variation with local environmental conditions can provide important insights into the evolutionary history and ecological dynamics of particular species (Marchán-Rivadeneira et al, 2012). The local environmental conditions can induce marked phenotypic differences.…”

“…The local environmental conditions can induce marked phenotypic differences. In some bat species it has been shown that factors related to temperature and precipitation could be important from the aspect of skull size variation (Burnett, 1983;Marchán-Rivadeneira et al, 2012). Santana and Lofgren (2013) observed that cranial shape in rhinolophids follows two major divisions that could reflect adaptations to dietary and environmental differences in African versus South Asian distributions.…”

“…Myotis auriculus and Myotis evotis (Gannon and Rácz, 2006), Myotis nigricans (Bornholdt et al, 2008), Myotis myotis, Myotis blythii and Myotis punicus (Evin et al, 2008), Monophyllus redmani (Mancina and Balseiro, 2010) and Artibeus lituratus (Marchán-Rivadeneira et al, 2012). Recently, Santana and Lofgren (2013) analyzed cranial modularity in 22 species of rhinolophid bats, as well as skull shape variation in relation to habitat across rhinolophids.…”

An Analysis ofMyotis peninsularis(Vespertilionidae) Blending Morphometric and Genetic Datasets

“…In isolated areas, such as islands, bats may exhibit dwarfism in comparison with their continental counterparts (Case, 1978) in its morphological characters (Caumul and Polly, 2005;Evin et al, 2011;Marchán-Rivadeneira et al, 2012). The Baja Cali fornia group fits this pattern as a group with geographical isolation.…”