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Population bottlenecks can reduce genetic diversity and may lead to inbreeding depression. However, some studies have provided evidence that long lifespans buffer negative genetic effects of bottlenecks. Others have cautioned that longevity might merely mask the effects of genetic drift, which will still affect long-term population viability. We used microsatellite data from actual populations of tuatara (Sphenodon punctatus) and eastern massasaugas (Sistrurus catenatus) as a starting point for simulated population declines to evaluate the performance of bottleneck tests under a range of scenarios. We quantified losses in genetic diversity for each scenario and assessed the power of commonly used tests (i.e., M-ratio, heterozygosity excess, and mode-shift) to detect known bottlenecks in these moderate- to long-lived species. Declines in genetic diversity were greater in bottlenecks simulated for eastern massasaugas, the shorter-lived species, and mode-shift and heterozygosity excess tests were more sensitive to population declines in this species. Conversely, M-ratio tests were more sensitive to bottlenecks simulated in tuatara. Despite dramatic simulated population declines, heterozygosity excess and mode-shift tests often failed to detect bottlenecks in both species, even when large losses in genetic diversity had occurred (both allelic diversity and heterozygosity). While not eliminating type II error, M-ratio tests generally performed best and were most reliable when a critical value (Mc) of 0.68 was used. However, in tuatara simulations, M-ratio tests had high rates of type I error when Mc was calculated assuming θ = 10. Our results suggest that reliance on these tests could lead to misguided species management decisions.

Microcystins are present in some aquatic organisms, but the potential transfer to and accumulation in terrestrial organisms is less understood. We measured microcystin concentrations in multiple terrestrial life stages of Hexagenia limbata to determine whether this cyanotoxin is transferred from one life stage to another and if H. limbata subimagos and imagos transport the algal toxin microcystin into terrestrial systems. Hexagenia limbata (n = 43) were hand collected from the shore of a low-nutrient lake with a history of Microcystis aeruginosa, located in Michigan’s Lower Peninsula. We quantified microcystin concentrations in H. limbata with enzyme linked immunosorbent assay (n = 39), with a subset verified with high performance liquid chromatography tandem mass spectrometry (n = 8, including duplicates). Microcystin ranged from the method limit of detection (MLOD) to 0.64 µg/g dry weight with detectable concentrations in subimagos, imagos, and spent females, indicating a potential for transport of this toxin to terrestrial systems. These data indicate that emerging aquatic insects are a potential vector for the transfer of microcystins from aquatic to terrestrial food webs and may pose a threat in and around systems with both H. limbata and more extensive blooms of M. aeruginosa.

The cyanobacterium, Microcystis aeruginosa, can produce the hepatotoxin microcystin. When toxic M. aeruginosa overwinters in the sediments of lakes, it may be ingested by aquatic insects and bioaccumulate in nymphs of Hexagenia mayflies. When volant Hexagenia emerge from lakes to reproduce, they provide an abundant, albeit temporary, food source for many terrestrial organisms including bats. Little brown bats, Myotis lucifugus, feed opportunistically on aquatic insects including Hexagenia. To determine if microcystin moves from aquatic to terrestrial ecosystems via trophic transfer, we combined a dietary analysis with the quantification of microcystin in bat livers and feces. In June 2014, coincident with the local Hexagenia emergence, bat feces were collected from underneath a maternity roost near Little Traverse Lake (Leelanau County, Michigan, USA). Insects in the diet were identified via molecular analyses of fecal pellets from the roost and from individual bats. Livers and feces were collected from 19 female M. lucifugus, and the concentrations of microcystin in these liver tissues and feces were measured using an enzyme-linked immunosorbent assay (ELISA) and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). We show that the majority of the bats' diets consisted of aquatic insects and that microcystin was detected in high concentrations (up to 129.9 μg/kg dw) in the bat feces by ELISA. Histopathological examination of three bat livers with the highest concentrations of microcystin showed no evidence of phycotoxicosis, indicating that M. lucifugus may not be immediately affected by the ingestion of microcystin. Future work could examine whether bats suffer delayed physiological effects from ingestion of microcystin.

African painted dogs (Lycaon pictus, APD) are highly endangered, with fewer than 7000 remaining in nature. Captive breeding programs can preserve a genetically diverse population and provide a source of individuals for reintroductions. However, most programs are initiated from few founders and suffer from low genetic diversity and inbreeding. The aims of this study were to use molecular markers to assess genetic variation, inbreeding, and relatedness among APDs in the North American captive population, to use these data to realign studbook records, and to compare these data to wild populations and to the European captive population to facilitate the development of a global management plan. We sequenced mitochondrial and major histocompatibility (MHC) class II loci and genotyped 14 microsatellite loci from 109 APDs from 34 institutions in North America. We identified three likely studbook errors and resolved ten cases of uncertain paternity. Overall, microsatellite heterozygosity was higher than reported in Europe, but effective population size estimates were lower. Mitochondrial sequence variation was extremely limited, and there were fewer MHC haplotypes than in Europe or the wild. Although the population did not show evidence of significant inbreeding overall, several individuals shared high relatedness values, which should be incorporated into future breeding programs.

Among felids worldwide, only 6 of 38 species have stable or increasing populations, and most felid species are threatened by anthropogenic influences, especially habitat loss and fragmentation. We documented changes in genetic diversity in an isolated, reintroduced population of bobcats on Cumberland Island (CUIS), Georgia, USA, compared to another bobcat population on Kiawah Island, South Carolina, USA, that was naturally established and experiences limited immigration from the mainland. The CUIS population declined from 32 reintroduced bobcats in 1989 to 10–24 individuals during 2012–2019, and observed heterozygosity declined from 0.742 to 0.634 (SD = 0.240). Observed heterozygosity of bobcats on Kiawah was 0.699 (SD = 0.153). We estimated that one bobcat immigrated to Kiawah Island every 5.3 years. We compared the predictions of a novel population viability analysis ( PVA ) to empirical estimates of abundance and genetic diversity on CUIS and used our PVA to identify management actions that are likely to support long-term viability. Mean heterozygosity from the PVA (0.588, SD = 0.065) was within 1 standard deviation of the empirical estimate. The PVA estimated the population would decline following population restoration due to loss of genetic diversity and inbreeding depression. Translocations of one female every four years would stabilize allele heterozygosity similar to the Kiawah Island population, but even translocations of two females every two years would not restore heterozygosity to founder levels. The PVA predicted no management action would result in a one in five probability of extinction within 50 years of reintroduction, but all translocation strategies nearly eliminated extinction risk through 100 years.

The North American Society for Bat Research (NASBR) began in 1970 at a turning point in history for women’s rights. Participation by women in NASBR has risen steadily over the society’s history, reflecting societal shifts of reducing barriers to advancement and achievement by women in science. Gender parity has been achieved in all forms of presentation type at NASBR (general and student oral presentation and poster sessions). The 50% milestone of women participants in the general oral presentations and as session chairs was only reached in 2015, whereas women have represented the majority of participants in student sessions since the 1990s. The current culture of inclusivity and support for gender and racial diversity in the NASBR society is viewed as generally positive based on a survey of NASBR affiliates. The current Society and annual NASBR meeting have made visible efforts to offer opportunities for raising awareness and discussion around diversity, provide mentoring opportunities, and codified expectations of behavior to create a safe and inclusive conference environment for all participants. Over the past 50 years, NASBR has not only supported and advanced research on bats but has grown as a society to reflect values of inclusion and support for all people working to advance research on bats.

Brazilian free-tailed bats (Tadarida brasiliensis) are one of the most widely distributed bat species in the Americas, often engaging in rapid, long-distance dispersals. Here, we document that, since ca. 2007, these bats have expanded their range into western North Carolina, eastern Tennessee, and Virginia. Reports from wildlife control professionals, wildlife rehabilitators, regional submissions of bats for rabies testing, acoustic monitoring, and the presence of T. brasiliensis in buildings and bat houses indicate that these bats are now established in year-round colonies in areas previously thought outside their range limits. The geographic distributions of many organisms are currently shifting to higher latitudes in response to changing climate. We hypothesize that a coldtolerant thermal physiology that allows these largely tropical bats to enter extended torpor contributes to the ability of T. brasiliensis to establish populations in formerly cooler regions, and propose that their rapid northward expansion is facilitated by climate change and their tendency to explore new habitats and use a wide diversity of roost sites. Because of their abundance and use of man-made structures, we anticipate that the range expansion of T. brasiliensis will have implications for public health, ecosystem services, and bat conservation.

The common vampire bat, Desmodus rotundus, ranges from South America into northern Mexico in North America. This sanguivorous species of bat feeds primarily on medium to large‐sized mammals and is known to rely on livestock as primary prey. Each year, there are hotspot areas of D. rotundus‐specific rabies virus outbreaks that lead to the deaths of livestock and economic losses. Based on incidental captures in our study area, which is an area of high cattle mortality from D. rotundus transmitted rabies, it appears that D. rotundus are being caught regularly in areas and elevations where they previously were thought to be uncommon. Our goal was to investigate demographic processes and genetic diversity at the north eastern edge of the range of D. rotundus in Mexico. We generated control region sequences (441 bp) and 12‐locus microsatellite genotypes for 602 individuals of D. rotundus. These data were analyzed using network analyses, Bayesian clustering approaches, and standard population genetic statistical analyses. Our results demonstrate panmixia across our sampling area with low genetic diversity, low population differentiation, loss of intermediate frequency alleles at microsatellite loci, and very low mtDNA haplotype diversity with all haplotypes being very closely related. Our study also revealed strong signals of population expansion. These results follow predictions from the leading‐edge model of expanding populations and supports conclusions from another study that climate change may allow this species to find suitable habitat within the U.S. border.

Large numbers of migratory bats are killed every year at wind energy facilities. However, population-level impacts are unknown as we lack basic demographic information about these species. We investigated whether fatalities at wind turbines could impact population viability of migratory bats, focusing on the hoary bat ( Lasiurus cinereus ), the species most frequently killed by turbines in North America. Using expert elicitation and population projection models, we show that mortality from wind turbines may drastically reduce population size and increase the risk of extinction. For example, the hoary bat population could decline by as much as 90% in the next 50 years if the initial population size is near 2.5 million bats and annual population growth rate is similar to rates estimated for other bat species (λ = 1.01). Our results suggest that wind energy development may pose a substantial threat to migratory bats in North America. If viable populations are to be sustained, conservation measures to reduce mortality from turbine collisions likely need to be initiated soon. Our findings inform policy decisions regarding preventing or mitigating impacts of energy infrastructure development on wildlife.

Determining the processes responsible for phenotypic variation is one of the central tasks of evolutionary biology. While the importance of acoustic traits for foraging and communication in echolocating mammals suggests adaptation, the seldom-tested null hypothesis to explain trait divergence is genetic drift. Here we derive F ST values from multi-locus coalescent isolation-with-migration models, and couple them with estimates of quantitative trait divergence, or P ST , to test drift as the evolutionary process responsible for phenotypic divergence in island populations of the Pteronotus parnellii species complex. Compared to traditional comparisons of P ST to F ST , the migration-based estimates of F ST are unidirectional instead of bidirectional, simultaneously integrate variation among loci and individuals, and posterior densities of P ST and F ST can be compared directly. We found the evolution of higher call frequencies is inconsistent with genetic drift for the Hispaniolan population, despite many generations of isolation from its Puerto Rican counterpart. While the Hispaniolan population displays dimorphism in call frequencies, the higher frequency of the females is incompatible with sexual selection. Instead, cultural drift toward higher frequencies among Hispaniolan females might explain the divergence. By integrating Bayesian coalescent and trait analyses, this study demonstrates a powerful approach to testing genetic drift as the default evolutionary mechanism of trait differentiation between populations.

Recent studies documented the potential transfer of microcystin, a hepatotoxin produced by some cyanobacteria, from aquatic to terrestrial ecosystems. Using enzyme linked immunosorbent assay, we measured microcystins in emergent Hexagenia limbata mayflies and fecal samples collected from a maternity colony of little brown bats (Myotis lucifugus) located adjacent to a Michigan (U.S.A.) lake that experiences seasonal blooms of toxicogenic Microcystis aeruginosa. All H. limbata and M. lucifugus fecal samples contained microcystin (H. limbata: mean = 293.88 ng/g dw ± 35.99 se, n = 39; M. lucifugus: mean = 262.10 ng/g dw ± 31.08 se, n = 20). Ingestion of this toxin may represent a previously unrecognized stressor on bat populations in this region.

Drivers of environmental change in one location can have profound effects on ecosystem services and human well-being in distant locations, often across international borders. The telecoupling provides a conceptual framework for describing these interactions - for example, locations can be defined as sending areas (sources of flows of ecosystem services, energy, or information) or receiving areas (recipients of flows). However, the ability to quantify feedbacks between ecosystem change in one area and societal benefits in other areas requires analytical approaches. We use spatial subsidies - an approach developed to measure the degree to which a migratory species' ability to provide services in one location depends on habitat in another location - as an example of how telecoupling can be operationalized. Using the cotton pest control and ecotourism services of Mexican free-tailed bats as an example, we determined that of the 16 states in the United States and Mexico where the species resides, three states (Texas, New Mexico, and Colorado) are receiving areas, while the rest of the states are sending areas. In addition, the magnitude of spatial subsidy can be used as an indicator of the degree to which different locations are telecoupled to other locations. In this example, the Mexican free-tailed bat ecosystem services to cotton production and ecotourism in Texas and New Mexico are heavily dependent on winter habitat in four states in central and southern Mexico. In sum, spatial subsidies can be used to operationalize the telecoupling conceptual framework by identifying sending and receiving areas, and by indicating the degree to which locations are telecoupled to other locations.

Conservation planning can be challenging due to the need to balance biological concerns about population viability with social concerns about the benefits biodiversity provide to society, often while operating under a limited budget. Methods and tools that help prioritize conservation actions are critical for the management of at-risk species. Here, we use a multi-attribute utility function to assess the optimal maternity roosts to conserve for maintaining the population viability and the ecosystem services of a single species, the Mexican free-tailed bat (Tadarida brasiliensis mexicana). Mexican free-tailed bats provide ecosystem services such as insect pest-suppression in agricultural areas and recreational viewing opportunities, and may be threatened by climate change and development of wind energy. We evaluated each roost based on five attributes: the maternity roost’s contribution to population viability, the pest suppression ecosystem services to the surrounding area provided by the bats residing in the roost, the ecotourism value of the roost, the risks posed to each roost structure, and the risks posed to the population of bats residing in each roost. We compared several scenarios that prioritized these attributes differently, hypothesizing that the set of roosts with the highest rankings would vary according to the conservation scenario. Our results indicate that placing higher values on different roost attributes (e.g. population importance over ecosystem service value) altered the roost rankings. We determined that the values placed on various conservation objectives are an important determinant of habitat planning.

Species delimitation using mitochondrial sequences aims to identify species as morphological expertise and biodiversity both decline. Species delimitation in animals relies completely or in part on 2 criteria: genetic distance and reciprocal monophyly. Using coalescent simulations of populations experiencing continuous and interrupted gene flow we show that these commonly applied criteria incur both high false-positive and high false-negative error rates in species delimitation when dispersal is sex biased, as it is in most mammals. The combination of distance- and topology-based criteria will incur false-positive error rates well above 5% when ancestral effective population sizes are large and when population structure has been in place for 10,000 years or more. This effect persists even with a subtle bias in dispersal of 1 : 4 female : males dispersing in each generation. High false-positive error rates in genetic distances can be overcome by correcting for within-population sequence divergence...

Until recently, the little brown bat (Myotis lucifugus) was one of the most common bat species in North America. However, this species currently faces a significant threat from the emerging fungal disease white-nose syndrome (WNS). The aims of this study were to examine the population genetic structure of M. lucifugus hibernating colonies in Pennsylvania (PA) and West Virginia (WV), and to determine whether that population structure may have influenced the pattern of spread of WNS. Samples were obtained from 198 individuals from both uninfected and recently infected colonies located at the crest of the disease front. Both mitochondrial (636 bp of cytochrome oxidase I) and nuclear (8 microsatellites) loci were examined. Although no substructure was evident from nuclear DNA, female-mediated gene flow was restricted between hibernacula in western PA and the remaining colonies in eastern and central PA and WV. This mitochondrial genetic structure mirrors topographic variation across the region: 3 hibernating colonies located on the western Appalachian plateau were significantly differentiated from colonies located in the central mountainous and eastern lowland regions, suggesting reduced gene flow between these clusters of colonies. Consistent with the hypothesis that WNS is transmitted primarily through bat-to-bat contact, these same 3 hibernating colonies in westernmost PA remained WNS-free for 1–2 years after the disease had swept through the rest of the state, suggesting that female migration patterns may influence the spread of WNS across the landscape.

Given rapid changes in agricultural practice, it is critical to understand how alterations in ecological, technological, and economic conditions over time and space impact ecosystem services in agroecosystems. Here, we present a benefit transfer approach to quantify cotton pest-control services provided by a generalist predator, the Mexican free-tailed bat (Tadarida brasiliensis mexicana), in the southwestern United States. We show that pest-control estimates derived using (1) a compound spatial–temporal model – which incorporates spatial and temporal variability in crop pest-control service values – are likely to exhibit less error than those derived using (2) a simple-spatial model (i.e., a model that extrapolates values derived for one area directly, without adjustment, to other areas) or (3) a simple-temporal model (i.e., a model that extrapolates data from a few points in time over longer time periods). Using our compound spatial–temporal approach, the annualized pest-control value was $12.2 million, in contrast to an estimate of $70.1 million (5.7 times greater), obtained from the simple-spatial approach. Using estimates from one year (simple-temporal approach) revealed large value differences (0.4 times smaller to 2 times greater). Finally, we present a detailed protocol for valuing pest-control services, which can be used to develop robust pest-control transfer functions for generalist predators in agroecosystems.EDITED BY Neville Crossman EDITED BY Neville Crossman

Ecological factors such as changing climate on land and interspecific competition have been debated as possible causes of postglacial Caribbean extinction. These hypotheses, however, have not been tested against a null model of climate-driven postglacial area loss. Here, we use a new Quaternary mammal database and deep-sea bathymetry to estimate species-area relationships (SARs) at present and during the Last Glacial Maximum (LGM) for bats of the Caribbean, and to model species loss as a function of area loss from rising sea level. Island area was a significant predictor of species richness in the Bahamas, Greater Antilles, and Lesser Antilles at all time periods, except for the Lesser Antilles during the LGM. Parameters of LGM and current SARs were similar in the Bahamas and Greater Antilles, but not the Lesser Antilles, which had fewer estimated species during the LGM than expected given their size. Estimated postglacial species losses in the Bahamas and Greater Antilles were largely explained by inferred area loss from rising sea level in the Holocene. However, there were more species in the Bahamas at present, and fewer species in the smaller Greater Antilles, than expected given island size and the end-Pleistocene/early Holocene SARs. Poor fossil sampling and ecological factors may explain these departures from the null. Our analyses illustrate the importance of changes in area in explaining patterns of species richness through time and emphasize the role of the SAR as a null hypothesis in explorations of the impact of novel ecological interactions on extinction.

During a Myotis sodalis telemetry project in Pennsylvania, USA, in 2000, road-killed M. lucifugus were recorded and a highway survey was initiated. The purpose of this study was to assess the level of mortality from road kills on this colony, verify which species were being killed in traffic and examine the influence of canopy height and structure on flight behavior. On 10 evenings between 15 May and 26 July 2001, bats were counted as they emerged from day roosts and crossed a heavily trafficked highway en route to foraging areas. A total of 26 442 bats were observed cross- ing this highway over 9.29 h of observation. Bats used canopy cover when approaching the highway from roosts. Where canopy cover was lacking adjacent to the highway, fewer bats were counted crossing; where adjacent canopy was low (≤6 m), bats crossed lower and closer to traffic. Motivated by a planned highway upgrade that would extend deforestation of the highway verge, we monitored the flight behavior of M. lucifugus as they crossed a 55 m mowed field. Observations of more than 1700 bats revealed that a vast majority of commuting individuals fly less than 2 m above the ground in the open field. Between 15 May and 14 September 2001, searches for road-killed bats were con- ducted along a section of highway crossed by large numbers of bats. We collected 27 road-killed M. lucifugus, 1 suspected M. sodalis and 1 unidentifiable Myotis sp. Subsequent genetic analyses of mitochondrial DNA sequences confirmed the suspect bat as a federally endangered M. sodalis.

We studied litter sizes, den characteristics, and den site selection by wolves (Canis lupus ligoni) on Prince of Wales and adjacent islands in Southeast Alaska, USA. The study area was extensively logged and roaded enabling us to examine effects of those factors on den site selection. We counted pups in dens during May using an infrared video camera with a flexible-shaft. We recorded habitat features at dens and used logistic regression to compare den site characteristics within 100-m and 1000-m circular buffers around dens with randomly matched unused locations. Litter size averaged 4.1 (SD = 1.7) pups, however, average litter sizes of six first-time breeding females were smaller ( = 3.0, SD = 2.5). Dens were located in root wads of large living or dead trees within old-growth forest stands

We investigate the genetic relationships between purported island species of Pteropus fruit bat (Megachiroptera) from the western Indian Ocean islands using mitochondrial DNA sequencing in order to infer the pattern of colonisation of this biogeographic region. Most significantly, our genetic data questions the current taxonomic assignment based on morphology of many of the island species and subspecies, suggesting instead that many of the western Indian Ocean islands harbour 'races' of P. giganteus from mainland India. Our results strongly argue against a single colonisation event from mainland Asia. Evidence is presented for three colonisation events; the first to the western-most extremity of their range (Comoros and Pemba Island), the second to Rodrigues Island; and a third giving rise to the remaining extant island taxa, the latter two events occurring relatively recently and rapidly.

We investigated the influence of habitat use on risk of death from hunting and trapping of 55 radiocollared gray wolves (Canis lupus) from an exploited insular population in Southeast Alaska, USA. We compared mortality rates for resident and nonresident wolves and used Cox proportional hazards regression to relate habitat composition within 100-m circular buffers around radiolocations to risk of death of resident and nonresident wolves. In addition, we included covariates representing distances to roads, logged stands, and lakes and streams in those analyses. We also compiled harvest data from 31 harvest units within the study area to compare densities of roads and distances from human settlements with rates of harvest. During our study 39 wolves died, of which 18 were harvested legally, 16 were killed illegally, and 5 died from natural causes. Legal and illegal harvest accounted for >87% of the mortality of radiocollared resident and nonresident wolves. Mean annual survival was 0.54 (SE = 0.17) for all wolves. Annual survival was 0.65 (SE = 0.17) for resident wolves and 0.34 (SE = 0.17) for nonresidents. Very few (19%) nonresident wolves survived to colonize vacant territories or join existing wolf packs. Roads, muskegs, and distances from lakes and streams were covariates positively associated with death of resident wolves. Clear-cuts were positively associated with risk of death of nonresident wolves. Rate of harvest increased with density of roads; however, road densities >0.9 km/km2 had little additional effect on harvest rates. Harvest rates decreased with ocean distances from nearest towns or settlements. Roads clearly increased risk of death for wolves from hunting and trapping and contributed to unsustainable rates of harvest. Wildlife managers should consider effects of roads and other habitat features on harvest of wolves when developing harvest recommendations. They should expect substantial illegal harvest where wolf habitat is accessible to humans. Moreover, high rates of mortality of nonresident wolves exposed to legal and illegal harvest may reduce or delay successful dispersal, potentially affecting linkages between small disjunct wolf populations or population segments. We conclude that a combination of conservative harvest regulations and large roadless reserves likely are the most effective measures for conserving wolves where risks from human-caused mortality are high.

The chiropteran family Myzopodidae is endemic to Madagascar and is characterized by several unique morphologies, such as sessile adhesive discs on the thumb and sole. A new species, Myzopoda schliemanni, was recently described from western Madagascar that is morphologically distinct and geographically disjunct from the eastern species, M. aurita, the only other member of this family. Geographic variation within Myzopoda has only recently been studied at the morphological level and has never been addressed at the genetic level. We used a combination of phylogenetic, coalescent, and population genetic analyses to characterize the speciation history of Myzopoda and to clarify current and former patterns of gene flow within and between Myzopoda. Mitochondrial DNA sequences were used to determine whether genetic data support the morphologically distinct species M. schliemanni, to infer the distribution of the common ancestor of extant Myzopoda, to estimate effective population sizes (Ne) and levels of migration between species, and to determine patterns of population structure within species. Phylogenetic and network analyses revealed the existence of 4 well-supported clades in Myzopoda, but could not resolve relationships among those clades. Divergent haplotypes within species may result from either recent gene flow between the 2 species or more likely from incomplete lineage sorting. Multiple coalescent-based methodologies produced concordant estimates of Ne for Myzopoda, but conflicting signals for migration between the species, probably reflecting differences in the underlying models used by the methods. We found significant genetic structure within M. aurita, but no correlation with geography. This pattern may result from recent gene flow facilitated by expansion of Ravenala stands, an important day-roost tree for Myzopoda, associated with anthropogenic deforestation and the opening up of new habitat for members of this genus.

Aim We investigate the directionality of mainland-to-island dispersals, focusing on a case study of an African-Malagasy bat genus, Triaenops (Hipposideridae). Taxa include T. persicus from east Africa and three Triaenops species from Madagascar (T. auritus, T. furculus, and T. rufus). The evolution of this bat family considerably post-dated the tectonic division of Madagascar from Africa, excluding vicariance as a viable hypothesis. Therefore, we consider three biogeographical scenarios to explain these species’ current ranges: (A) a single dispersal from Africa to Madagascar with subsequent speciation of the Malagasy species; (B) multiple, unidirectional dispersals from Africa to Madagascar resulting in multiple, independent Malagasy lineages; or (C) early dispersal of a proto-species from Africa to Madagascar, with later back-dispersal of a descendant Malagasy taxon to Africa. Location East Africa, Madagascar, and the Mozambique Channel. Methods We compare the utility of phylogenetic and coalescent methodologies to address the question of directionality in a mainland-to-island dispersal event for recently diverged taxa. We also emphasize the application of biologically explicit demographic systems, such as the non-equilibrium isolation-withmigration model. Here, these methods are applied to a four-species haploid genetic data set, with simulation analyses being applied to validate this approach. Results Coalescent simulations favour scenario B: multiple, unidirectional dispersals from Africa to Madagascar resulting in multiple, independent Malagasy bat lineages. From coalescent dating, we estimate that the genus Triaenops was still a single taxon approximately 2.25 Ma. The most recent Africa to Madagascar dispersal occurred much more recently (c. 660 ka), and led to the formation of the extant Malagasy species, T. rufus.

New applications of genetic data to questions of historical biogeography have revolutionized our understanding of how organisms have come to occupy their present distributions. Phylogenetic methods in combination with divergence time estimation can reveal biogeographical centres of origin, differentiate between hypotheses of vicariance and dispersal, and reveal the directionality of dispersal events. Despite their power, however, phylogenetic methods can sometimes yield patterns that are compatible with multiple, equally well-supported biogeographical hypotheses. In such cases, additional approaches must be integrated to differentiate among conflicting dispersal hypotheses. Here, we use a synthetic approach that draws upon the analytical strengths of coalescent and population genetic methods to augment phylogenetic analyses in order to assess the biogeographical history of Madagascar's Triaenops bats (Chiroptera: Hipposideridae). Phylogenetic analyses of mitochondrial DNA sequence data for Malagasy and east African Triaenops reveal a pattern that equally supports two competing hypotheses. While the phylogeny cannot determine whether Africa or Madagascar was the centre of origin for the species investigated, it serves as the essential backbone for the application of coalescent and population genetic methods. From the application of these methods, we conclude that a hypothesis of two independent but unidirectional dispersal events from Africa to Madagascar is best supported by the data.

Incomplete lineage sorting can genetically link populations long after they have diverged, and will exert a more powerful influence on larger populations. The effects of this stochastic process can easily be confounded with those of gene flow, potentially leading to inaccurate estimates of dispersal capabilities or erroneous designation of evolutionarily significant units (ESUs). We have used phylogenetic, population genetic, and coalescent methods to examine genetic structuring in large populations of a widely dispersing bat species and to test hypotheses concerning the influences of coalescent stochasticity vs. gene flow. The Mexican free-tailed bat, Tadarida brasiliensis mexicana, exhibits variation in both migratory tendency and route over its range. Observations of the species' migratory behaviour have led to the description of behaviourally and geographically defined migratory groups, with the prediction that these groups compose structured gene pools. Here, we used mtDNA sequence analyses coupled with existing information from allozyme, banding, and natural history studies to evaluate hypotheses regarding the relationship between migration and genetic structure. Analyses of molecular variance revealed no significant genetic structuring of behaviourally distinct migratory groups. Demographic analyses were consistent with population growth, although the timing of population expansion events differs between migratory and nonmigratory populations. Hypotheses concerning the role of gene flow vs. incomplete lineage sorting on these data are explored using coalescent simulations. Our study demonstrates the importance of accounting for coalescent stochasticity in formulating phylogeographical hypotheses, and indicates that analyses that do not take such processes into account can lead to false conclusions regarding a species' phylogeographical history.

Critics of the market-based, ecosystem services approach to biodiversity conservation worry that volatile market conditions and technological substitutes will diminish the value of ecosystem services and obviate the “economic benefits” arguments for conservation. To explore the effects of market forces and substitutes on service values, we assessed how the value of the pest-control services provided by Mexican free-tailed bats (Tadarida brasiliensis mexicana) to cotton production in the southwestern U.S. has changed over time. We calculated service values each year from 1990 through 2008 by estimating the value of avoided crop damage and the reduced social and private costs of insecticide use in the presence of bats. Over this period, the ecosystem service value declined by 79% ($19.09 million U.S. dollars) due to the introduction and widespread adoption of Bt (Bacillus thuringiensis) cotton transgenically modified to express its own pesticide, falling global cotton prices and the reduction in the number of hectares in the U.S. planted with cotton. Our results demonstrate that fluctuations in market conditions can cause temporal variation in ecosystem service values even when ecosystem function – in this case bat population numbers – is held constant. Evidence is accumulating, however, of the evolution of pest resistance to Bt cotton, suggesting that the value of bat pest-control services may increase again. This gives rise to an economic option value argument for conserving Mexican free-tailed bat populations. We anticipate that these results will spur discussion about the role of ecosystem services in biodiversity conservation in general, and bat conservation in particular.

Pteropids are large, highly mobile bats that are distributed widely across islands of the Pacific and Indian Oceans, southern Asia, and Australia. Dispersal behaviors and colonization patterns of pteropid species among oceanic islands are poorly known. In the southern Pacific, Pteropus samoensis and P. tonganus have partially overlapping ranges, existing in sympatry on the Samoan and Fijian archipelagos. These species exhibit differences in morphology and roosting behavior, with P. samoensis being smaller and tending to roost solitarily or in small groups. Here, we use genetic data to explore whether these species also exhibit differences with regard to patterns of population genetic structure within and between these archipelagos. Phylogenetic analyses of mitochondrial DNA are consistent with earlier morphological recognition of different subspecies of P. samoensis on the Samoan vs. Fijian archipelagos. Patterns of mtDNA haplotype sharing suggest that P. tonganus experiences restricted gene flow between,...

We have studied both the frequency and biogeographical distribution of the transposable DNA element mariner in natural populations of Drosophila simulans and the short-term evolutionary characteristics of mariner in experimental populations. The mariner element has been identified in natural populations of D. simulans from Africa, Europe, the Middle East, Japan, Australia, several Pacific islands, North America, and South America. Only four lines out of 296 were devoid of active mariner elements, as measured by the presence of functional mariner transposase. A slight correlation was found between the latitudinal coordinate of the collection sites and the level of mariner activity in the population; this correlation became highly significant in Australia where a cline in mariner activity was observed along the eastern coast of the continent. We also observed that wild-type laboratory strains kept for several years as small populations might lose mariner activity over time. Using experimental populations, we modeled what might happen when naturally occurring populations exhibiting high and low levels of mariner activity encounter one another. We found that active mariner elements either will tend to lose their activity over time and gradually become inactive or possibly will be lost from the population; in either case, this will lead to the pattern seen in this experiment of a significant loss of mariner activity over time.

We present three dinucleotide and six tetranucleotide microsatellite loci that were developed for the Brazilian free-tailed bat, Tadarida brasiliensis (Chiroptera, Molossidae). Ninety-one individuals from two populations were scored at each locus, revealing extremely high levels of polymorphism (15‐55 alleles per locus). These loci provide genetic markers for studying gene flow, migration and mating behaviour.

Background Human activities, such as agriculture, hunting, and habitat modification, exert a significant effect on native species. Although many species have suffered population declines, increased population fragmentation, or even extinction in connection with these human impacts, others seem to have benefitted from human modification of their habitat. Here we examine whether population growth in an insectivorous bat (Tadarida brasiliensis mexicana) can be attributed to the widespread expansion of agriculture in North America following European settlement. Colonies of T. b. mexicana are extremely large (~106 individuals) and, in the modern era, major agricultural insect pests form an important component of their food resource. It is thus hypothesized that the growth of these insectivorous bat populations was coupled to the expansion of agricultural land use in North America over the last few centuries. Results We sequenced one haploid and one autosomal locus to determine the rate and time of onset of population growth in T. b. mexicana. Using an approximate Maximum Likelihood method, we have determined that T. b. mexicana populations began to grow ~220 kya from a relatively small ancestral effective population size before reaching the large effective population size observed today. Conclusions Our analyses reject the hypothesis that T. b. mexicana populations grew in connection with the expansion of human agriculture in North America, and instead suggest that this growth commenced long before the arrival of humans. As T. brasiliensis is a subtropical species, we hypothesize that the observed signals of population growth may instead reflect range expansions of ancestral bat populations from southern glacial refugia during the tail end of the Pleistocene.

Observed patterns of genetic structure result from the interactions of demographic, physical, and historical influences on gene flow. The particular strength of various factors in governing gene flow, however, may differ between species in biologically relevant ways. We investigated the role of demographic factors (population size and sex-biased dispersal) and physical features (geographic distance, island size and climatological winds) on patterns of genetic structure and gene flow for two lineages of Greater Antillean bats. We used microsatellite genetic data to estimate demographic characteristics, infer population genetic structure, and estimate gene flow among island populations of Erophylla sezekorni/E. bombifrons and Macrotus waterhousii (Chiroptera: Phyllostomidae). Using a landscape genetics approach, we asked if geographic distance, island size, or climatological winds mediate historical gene flow in this system. Samples from 13 islands spanning Erophylla's range clustered into five genetically distinct populations. Samples of M. waterhousii from eight islands represented eight genetically distinct populations. While we found evidence that a majority of historical gene flow between genetic populations was asymmetric for both lineages, we were not able to entirely rule out incomplete lineage sorting in generating this pattern. We found no evidence of contemporary gene flow except between two genetic populations of Erophylla. Both lineages exhibited significant isolation by geographic distance. Patterns of genetic structure and gene flow, however, were not explained by differences in relative effective population sizes, island area, sex-biased dispersal (tested only for Erophylla), or surface-level climatological winds. Gene flow among islands appears to be highly restricted, particularly for M. waterhousii, and we suggest that this species deserves increased taxonomic attention and conservation concern.

The little brown bat (Myotis lucifugus) is one of the most widespread bat species in North America and is experiencing severe population declines because of an emerging fungal disease, white-nose syndrome (WNS). To manage and conserve this species effectively it is important to understand patterns of gene flow and population connectivity to identify possible barriers to disease transmission. However, little is known about the population genetic structure of little brown bats, and to date, no studies have investigated population structure across their entire range. We examined mitochondrial DNA and nuclear microsatellites in 637 little brown bats (including all currently recognized subspecific lineages) from 29 locations across North America, to assess levels of genetic variation and population differentiation across the range of the species, including areas affected by WNS and those currently unaffected. We identified considerable spatial variation in patterns of female dispersal and significant genetic variation between populations in eastern versus western portions of the range. Overall levels of nuclear genetic differentiation were low, and there is no evidence for any major barriers to gene flow across their range. However, patterns of mtDNA differentiation are highly variable, with high ΦST values between most sample pairs (including between all western samples, between western and eastern samples, and between some eastern samples), while low mitochondrial differentiation was observed within two groups of samples found in central and eastern regions of North America. Furthermore, the Alaskan population was highly differentiated from all others, and western populations were characterized by isolation by distance while eastern populations were not. These data raise the possibility that the current patterns of spread of WNS observed in eastern North America may not apply to the entire range and that there may be broad-scale spatial variation in the risk of WNS transmission and occurrence if the disease continues to spread west.

The Hawaiian islands are an extremely isolated oceanic archipelago, and their fauna has long served as models of dispersal in island biogeography. While molecular data have recently been applied to investigate the timing and origin of dispersal events for several animal groups including birds, insects, and snails, these questions have been largely unaddressed in Hawai'i's only native terrestrial mammal, the Hawaiian hoary bat, Lasiurus cinereus semotus. Here, we use molecular data to test the hypotheses that (1) Hawaiian L. c. semotus originated via dispersal from North American populations of L. c. cinereus rather than from South American L. c. villosissimus, and (2) modern Hawaiian populations were founded from a single dispersal event. Contrary to the latter hypothesis, our mitochondrial data support a biogeographic history of multiple, relatively recent dispersals of hoary bats from North America to the Hawaiian islands. Coalescent demographic analyses of multilocus data suggest that modern populations of Hawaiian hoary bats were founded no more than 10 kya. Our finding of multiple evolutionarily significant units in Hawai'i highlights information that should be useful for re-evaluation of the conservation status of hoary bats in Hawai'i.

Studies in molecular ecology depend on field-collected samples for genetic information, and the tissue sampled and preservation conditions strongly affect the quality of the DNA obtained. DNA yields from different tissue types have seldom been compared, and the relative performance of storage media has never been directly tested, even though these media may influence DNA degradation under field conditions. We analyzed DNA yield from buccal swabs and wing punches harvested from live bats using nucleic acid quantification as well as quantitative PCR for a single-copy nuclear locus. We also compared DNA yields from wing tissue preserved in three media: ethanol, NaCl-saturated dimethyl sulfoxide (DMSO), and silica desiccant. Wing punches yielded more total DNA than did buccal swabs, and wing tissues preserved in silica beads yielded significantly more total and nuclear DNA than those preserved in DMSO or ethanol. These results show that tissue type and preservation media strongly influence the quantity of DNA obtained from non-lethal genetic samples, and based on these effects we provide recommendations for field collection of tissues for genetic analyses.

The biodiversity of Madagascar is extraordinarily distinctive, diverse, and endangered. It is therefore urgent that steps be taken to document, describe, interpret, and protect this exceptional biota. As a collaborative group of field and laboratory biologists, we employ a suite of methodological and analytical tools to investigate the vertebrate portion of Madagascar's fauna. Given that species are the fundamental unit of evolution, where micro- and macroevolutionary forces converge to generate biological diversity, a thorough understanding of species distribution and abundance is critical for understanding the evolutionary, ecological, and biogeographic forces that have shaped Malagasy vertebrate diversity. We illustrate the means by which we apply Mayr's “three basic tasks” of the systematist [Mayr, E. (1942) Systematics and the Origin of Species from the Viewpoint of a Zoologist (Harvard Univ. Press, Cambridge, MA)] to identify, classify, and study the organisms that together constitute Madagascar's vertebrate community. Using field inventory methods, specimen-based studies, and morphological and molecular analyses, we formulate hypotheses of species identity that then serve as the foundation for subsequent studies of biology and history. Our experience, as well as that of other investigators, has shown that much of the vertebrate species diversity in Madagascar is “cryptic” for both biological and practical reasons. Beyond issues of cryptic biological diversity, the resolution of species identity in Madagascar has been hampered because of a lack of vouchered comparative material at the population level. Through our activities, we are attempting to remedy these limitations while simultaneously enhancing research capacity in Madagascar.

The migration of animals across long distances and between multiple habitats presents a major challenge for conservation. For the migratory Mexican free-tailed bat (Tadarida brasiliensis mexicana), these challenges include identifying and protecting migratory routes and critical roosts in two countries, the United States and Mexico. Knowledge and conservation of bat migratory routes is critical in the face of increasing threats from climate change and wind turbines that might decrease migratory survival. We employ a new modeling approach for bat migration, network modeling, to simulate migratory routes between winter habitat in southern Mexico and summer breeding habitat in northern Mexico and the southwestern United States. We use the model to identify key migratory routes and the roosts of greatest conservation value to the overall population. We measure roost importance by the degree to which the overall bat population declined when the roost was removed from the model. The major migratory routes—those with the greatest number of migrants—were between winter habitat in southern Mexico and summer breeding roosts in Texas and the northern Mexican states of Sonora and Nuevo Leon. The summer breeding roosts in Texas, Sonora, and Nuevo Leon were the most important for maintaining population numbers and network structure - these are also the largest roosts. This modeling approach contributes to conservation efforts by identifying the most influential areas for bat populations, and can be used to as a tool to improve our understanding of bat migration for other species. We anticipate this approach will help direct coordination of habitat protection across borders.

We describe a new species of bat in the genus Emballonura (Chiroptera: Emballonuridae), E. tiavato, from the dry forest regions of Madagascar. This species is distinguished from the only other member of this genus found on the island, E. atrata, and extralimital species based on a variety of external and cranial characteristics. Details of the distribution, phylogeny, and natural history of the two species of Malagasy Emballonura are presented.

Background: Debate continues as to whether allopatric speciation or peripatric speciation through a founder effect is the predominant force driving evolution in vertebrates. The mouse lemurs of Madagascar are a system in which evolution has generated a large number of species over a relatively recent time frame. Here, we examine speciation patterns in a pair of sister species of mouse lemur, Microcebus murinus and M. griseorufus. These two species have ranges that are disparately proportioned in size, with M. murinus showing a much more extensive range that marginally overlaps that of M. griseorufus. Given that these two species are sister taxa, the asymmetric but overlapping geographic ranges are consistent with a model of peripatric speciation. To test this hypothesis, we analyze DNA sequence data from four molecular markers using coalescent methods. If the peripatric speciation model is supported, we predict substantially greater genetic diversity in M. murinus, relative to M. griseorufus. Further, we expect a larger effective population size in M. murinus and in the common ancestor of the two species than in M. griseorufus, with a concomitant decrease in gene tree/species tree incongruence in the latter and weak signs of demographic expansion in M. murinus. Results: Our results reject a model of peripatric divergence. Coalescent effective population size estimates were similar for both extant species and larger than that estimated for their most recent common ancestor. Gene tree results show similar levels of incomplete lineage sorting within species with respect to the species tree, and locus-specific estimates of genetic diversity are concordant for both species. Multilocus demographic analyses suggest range expansions for M. murinus, with this species also experiencing more recent population declines over the past 160 thousand years. Conclusions: Results suggest that speciation occurred in allopatry from a common ancestor narrowly distributed throughout southwest Madagascar, with subsequent range expansion for M. murinus. Population decline in M. murinus is likely related to patterns of climate change in Madagascar throughout the Pleistocene, potentially exacerbated by continual anthropogenic perturbation. Genome-level data are needed to quantify the role of niche specialization and adaptation in shaping the current ranges of these species.