Sex‐biased gene flow and colonization in the Formosan lesser horseshoe bat: inference from nuclear and mitochondrial markers

Abstract

Sex-biased behaviours are expected to play an important role in partitioning genetic variance in animal populations. Comparing genetic structure at markers with different modes of inheritance provides a means of detecting these behaviours and their consequences for population genetic structure. In colonially breeding mammals, the common combination of female philopatry and male vagility can promote contrasting patterns of genetic differentiation between the sexes, both via their effects on recurrent gene flow and on colonization. We examined sex differences in gene flow and structure by comparing maternally inherited mitochondrial DNA (mtDNA) and biparentally inherited autosomal loci in the Formosan lesser horseshoe bat Rhinolophus monoceros. We found that genetic partitioning was higher at mtDNA than autosomal markers in both sexes, indicative of female-biased philopatry and male-biased dispersal. Across Taiwan, isolation-by-distance was detected for all sex/marker combinations but was steeper for mtDNA than for nuclear markers. We suggest that isolation-by-distance shown from mtDNA at large scales is likely to reflect the stepwise founding of new breeding colonies by females during colonization. In contrast, no isolation-bydistance was found at smaller distances of up to 100 km, indicating that gene flow and/or recent shared ancestry homogenises genetic structure among nearby sites. Our results highlight the value of an indirect genetic approach to understanding sex-biased behaviours and their consequences in a little-studied species.

Demographic loss, genetic structure and the conservation implications for Indian tigers

“…The difference between AMOVA patterns for mtDNA and microsatellites could reflect the lower effective size for mtDNA, allowing differentiation to accumulate more rapidly [27]. Conflicting patterns for mtDNA and nuclear DNA are common for mammals with female philopatry and male-biased dispersal [28]. In contrast to females, male tigers have large home ranges and are capable of dispersing up to 280 km [58].…”

“…Further, since genetic variation is often geographically structured and can be modified by species-specific behavioural patterns [27,28], the effects of local extinctions on range-wide genetic variation can exceed that predicted by population size change alone, resulting in a non-additive loss of unique genetic variants and an increase in genetic structure [29][30][31]. However, to understand the impact of habitat loss not only on genetic variation, but also on its partitioning, knowledge of the time period through which changes in habitat took place is important.…”

Conserving the endangered Mexican fishing bat (Myotis vivesi): genetic variation indicates extensive gene flow among islands in the Gulf of California

“…myotis, Ruedi and Castella 2003;M. bechsteinii, Kerth et al 2008) and is generally attributed to strong female philopatry and extensive, male-biased dispersal (Chen et al 2008). In addition, we found no isolation by distance pattern with mtDNA markers.…”

“…On the other hand, results from our mtDNA analyzes suggest that this high gene flow might not translate into high probabilities that restored islands will be recolonized. Strong female philopatry seems to be the rule in vespertilionid bats (e.g., Petit and Mayer 1999;Castella et al 2001;Ruedi and Castella 2003;Chen et al 2008); and when dispersal is rare, colonization of empty habitat might be even rarer (Kerth and Petit 2005). In addition, interisland gene flow can occur in ways other than individuals immigrating to an island and reproducing there.…”

Sex-biased dispersal in a northern ungulate population

“…In many ungulate species polygony and philopatry thus involves a pronounced fine-scale genetic structure (Mathews & Porter, 1993;Petit et al 1997;Purdue et al, 2000;Coltman et al, 2003;Nussey et al, 2005). Sex-biased dispersal at the subpopulation and meta-population levels has however been poorly documented (Prugnolle & de Meeus, 2002), but has recently been reported for turtles (Bowen & Karl, 2007) and bats (Chen et al, 2008).…”