Correlated Genetic and Ecological Diversification in a Widespread Southern African Horseshoe Bat

The analysis of molecular data within a historical biogeographical framework, coupled with ecological characteristics can provide insight into the processes driving diversification. Here we assess the genetic and ecological diversity within a widespread horseshoe bat Rhinolophus clivosus sensu lato with specific emphasis on the southern African representatives which, although not currently recognized, were previously described as a separate species R. geoffroyi comprising four subspecies. Sequence divergence estimates of the mtDNA control region show that the southern African representatives of R. clivosus s.l. are as distinct from samples further north in Africa than they are from R. ferrumequinum, the sister-species to R. clivosus. Within South Africa, five genetically supported geographic groups exist and these groups are corroborated by echolocation and wing morphology data. The groups loosely correspond to the distributions of the previously defined subspecies and Maxent modelling shows a strong correlation between the detected groups and ecoregions. Based on molecular clock calibrations, it is evident that climatic cycling and related vegetation changes during the Quaternary may have facilitated diversification both genetically and ecologically

The Relative Influence of Competition and Prey Defenses on the Phenotypic Structure of Insectivorous Bat Ensembles in Southern Africa

Deterministic filters such as competition and prey defences should have a strong influence on the community structure of animals such as insectivorous bats that have life histories characterized by low fecundity, low predation risk, long life expectancy, and stable populations. We investigated the relative influence of these two deterministic filters on the phenotypic structure of insectivorous bat ensembles in southern Africa. We used null models to simulate the random phenotypic patterns expected in the absence of competition or prey defences and analysed the deviations of the observed phenotypic pattern from these expected random patterns. The phenotypic structure at local scales exhibited non-random patterns consistent with both competition and prey defense hypotheses. There was evidence that competition influenced body size distribution across ensembles. Competition also influenced wing and echolocation patterns in ensembles and in functional foraging groups with high species richness or abundance. At the same time, prey defense filters influenced echolocation patterns in two species-poor ensembles. Non-random patterns remained evident even after we removed the influence of body size from wing morphology and echolocation parameters taking phylogeny into account. However, abiotic filters such as geographic distribution ranges of small and large-bodied species, extinction risk, and the physics of flight and sound probably also interacted with biotic filters at local and/or regional scales to influence the community structure of sympatric bats in southern Africa. Future studies should investigate alternative parameters that define bat community structure such as diet and abundance to better determine the influence of competition and prey defences on the structure of insectivorous bat ensembles in southern Africa

The Divergence of Echolocation Frequency in Horseshoe Bats: Moth Hearing, Body Size or Habitat?

A phylogenetic approach was used to test three hypotheses regarding the evolution of diversity in the echolocation frequencies used by horseshoe bats (family Rhinolophidae, genus Rhinolophus): 1) Allotonic Frequency Hypothesis (high frequency echolocation in the Rhinolophidae resulted from coevolution with moth hearing); 2) Allometry Hypothesis (echolocation frequency is negatively scaled with body size and evolutionary changes in echolocation frequencies are correlated with changes in body size in the Rhinolophidae); and 3) Foraging Habitat Hypothesis (evolution of echolocation frequency is associated with changes in habitat type). Both discrete and continuous character sets were used for ancestral state reconstructions and for investigating patterns of evolution between frequency and body size, and frequency and habitat type. Contrary to the prediction of the Allotonic Frequency Hypothesis, echolocation frequency in the Rhinolophidae did not increase over time, which would be expected if moth hearing and bat echolocation frequency coevolved. The number of extant species that exhibit calls within moth hearing ranges was not significantly different from the number of species that echolocate outside of moth hearing range. There was also no correlation between changes in frequency and changes in habitat type as predicted by the Foraging Habitat Hypothesis. Instead, the evolution of echolocation frequency within the Rhinolophidae was correlated with changes in body size as predicted by the Allometry Hypothesis. © 2011 Springer Science+Business Media, LLC.Articl

Molecular phylogenetics and historical biogeography of Rhinolophus bats

The phylogenetic relationships within the horseshoe bats (genus Rhinolophus) are poorly resolved, particularly at deeper levels within the tree. We present a better-resolved phylogenetic hypothesis for 30 rhinolophid species based on parsimony and Bayesian analyses of the mitochondrial cytochrome b gene and three nuclear introns (TG, THY and PRKC1). Strong support was found for the existence of two geographic clades within the monophyletic Rhinolophidae: an African group and an Oriental assemblage. The relaxed Bayesian clock method indicated that the two rhinolophid clades diverged approximately 35 million years ago and results from Dispersal Vicariance (DIVA) analysis suggest that the horseshoe bats arose in Asia and subsequently dispersed into Europe and Africa. © 2009 Elsevier Inc. All rights reserved.Articl

High diversity of pipistrelloid bats (Vespertilionidae:<I> Hypsugo, Neoromicia</I>, and <I>Pipistrellus</I>) in a West African rainforest with the description of a new species

Please help populate SUNScholar with the full text of SU research output. Also - should you need this item urgently, please send us the details and we will try to get hold of the full text as quick possible. E-mail to [email protected]. Thank you.Journal Articles (subsidised)NatuurwetenskappePlant- en Dierkund

Molecular phylogenetics and historical biogeography of Rhinolophus bats

The phylogenetic relationships within the horseshoe bats (genus Rhinolophus) are poorly resolved, particularly at deeper levels within the tree. We present a better-resolved phylogenetic hypothesis for 30 rhinolophid species based on parsimony and Bayesian analyses of the mitochondrial cytochrome b gene and three nuclear introns (TG, THY and PRKC1). Strong support was found for the existence of two geographic clades within the monophyletic Rhinolophidae: an African group and an Oriental assemblage. The relaxed Bayesian clock method indicated that the two rhinolophid clades diverged approximately 35 million years ago and results from Dispersal Vicariance (DIVA) analysis suggest that the horseshoe bats arose in Asia and subsequently dispersed into Europe and Africa. © 2009 Elsevier Inc. All rights reserved.Articl

Field identification of two morphologically similar bats, Miniopterus schreibersii natalensis and Miniopterus fraterculus (Chiroptera: Vespertilionidae)

Miniopterus schreibersii natalensis and Miniopterus fraterculus are two morphologically similar, but genetically distinct, species of insectivorous bat that, more often than not, share roosts. Identifying these two species in the field is difficult because of an overlap in the ranges of both forearm and mass. We thus attempted to find morphological features that could be used to distinguish between these two species in the field. We compared cranial and external morphological measurements from museum specimens of the two species, using principal component analysis and discriminant function analysis, to determine which variables could be used to discriminate between them. Length of the hind foot and total body length were identified as the variables responsible for most of the variation between these two species. Miniopterus s. natalensis has a longer total body length (113.6 ± 3.5 mm) than M. fraterculus (102.2 ± 4.8mm) but a relatively shorter hind foot (9.1 ± 0.6 mm, 9.8 ± 0.8 mm, respectively). A function generated from standardized canonical variables, (HF × 0.279417) – (TL × 0.989306) + 100, and based on length of hind foot (HF) and total body length (TL) generated function scores &lt;0 for M. s. natalensis and &gt;0 for M. fraterculus. On the basis that positive values (above zero) indicated M. fraterculus, and negative values (below zero) indicated M. s. natalensis, we were able to correctly assign 20 individuals to their respective species using the above function. These individuals were previously identified as M. fraterculus or M. s. natalensis from their mtDNA sequences. The function thus provides a useful tool for discriminating between the two species in the field.Keywords: cryptic species, field identification, morpholog

Diversity of Hipposideridae in the Mount Nimba massif, West Africa, and the taxonomic status of <I>Hipposideros lamottei</I>

Please help populate SUNScholar with the full text of SU research output. Also - should you need this item urgently, please send us the details and we will try to get hold of the full text as quick possible. E-mail to [email protected]. Thank you.Journal Articles (subsidised)NatuurwetenskappePlant- en Dierkund