ABSTRACT Flying foxes of the genus Pteropus are amongst the largest fruit bats and potential long-range pollinators and seed dispersers in the paleotropics. Pteropus giganteus (currently P. medius) is the only flying fox that is distributed throughout the Indian mainland, including in urban and rural areas. Using GPS telemetry, we mapped the home ranges and examined flight patterns in P. giganteus males across moon phases in a semi-urban landscape in southern India. Home range differed between the tracked males (n=4), likely due to differences in their experience in the landscape. We found that nightly time spent outside the roost, distance commuted and the number of sites visited by tracked individuals did not differ significantly between moon phases. In 61% of total tracked nights across bats, the first foraging site was within 45˚ of the emergence direction. At the colony-level, scan-based observations showed emergence flights were mostly in the northeast (27%), west (22%) and southwest (19%) directions that could potentially be related to the distribution of foraging resources. The movement ecology of fruit bats in relation to the pollination and seed dispersal services they provide requires to be investigated in future studies. This article has an associated First Person interview with the first author of the paper.

Bats constitute the second most speciose order of mammals and are known for their gregarious and flexible social structure. Urbanisation can lead to changes in the availability of, or access to, resources, such as roosting sites, food, and mates, and thus can potentially affect the social and mating systems. In this chapter, we summarise knowledge of the effects of urbanisation on the social structure of bats and highlight gaps in the literature. Further, we discuss the social structure and reproductive output of Cynopterus sphinx, a fruit bat ubiquitous across human-dominated habitats in South and Southeast Asia. We followed two C. sphinx colonies over multiple seasons to understand how urbanisation impacts the social systems of these colonies. We used direct observational and genetic data to compare the colony size, social subunit size, relatedness, and reproductive output of both colonies. On average, the rural colony was larger than the urban colony. The two colonies did not differ significantly with respect to social subunit size and relatedness, suggesting minimal impact of urbanisation on social structure. However, there was a significant difference in reproductive output, with the reproductive success of females from the rural colony being 1.7 times greater than that of the urban colony. Our results from a single rural and urban colony located nearly 500 km apart suggest that urbanisation may reduce fecundity and urban areas may act as ecological traps. Future studies with more extensive sampling are needed to identify the main drivers of female reproductive success and the cause of reduced female fecundity in urbanised habitats.

Peninsular India is an important region for mammalian diversification and harbors major biogeographic barriers. However, little is known about the role of this region in the diversification of bats though it harbors high chiropteran diversity. In this study, we used phenotypic, acoustic, and genetic markers to assess the diversification of Rhinolophus lepidus bats in South Asia. We first investigated if peninsular India is associated with speciation of R. lepidus. Further, we tested if the Palghat Gap acts as a biogeographic barrier to gene flow in this species. Our results revealed cryptic genetic diversity in peninsular India suggesting that this region holds at least one endemic species level lineage of the R. lepidus species complex. Analyses of populations of R. lepidus across the Palghat Gap in the Western Ghats revealed clinal variation in phenotype, with bats south of this barrier being bigger and emitting echolocation calls of higher frequency. We also observed that populations on either side of the Palghat Gap have remained genetically isolated since the mid-Holocene.

The Lesser Dog-faced Fruit Bat Cynopterus brachyotis was found at higher elevations but since there is a paucity of reports on its distribution and habitat selection, an inventory was made at four locations in the Eastern and Western Ghats of southern India where the elevation ranged from 200–1,500 m.  The C. brachyotis roosts were distributed between 600–1,500 m.  Day roosts were found at an elevation of about 1,000m in Sirumalai and Yercaud Hill stations.  Mist-netting studies, however, revealed that C. brachyotis was widely distributed at different elevations ranging from 600–1,500 m.  Moreover, through a radio-telemetry study, we determined that the males foraged at shorter distances from the day roost, whereas the females commuted longer distances and used more than one foraging area.  The male bats’ time of emergence is significantly less than females; in addition, males frequently return to their day-roost and made several short foraging flights spaced randomly throughout the night. These observations suggest that some type of territoriality is associated with their roost, which appears to be the basis of social organization in C. brachyotis.  Overall, this study provides detailed information about the foraging and roosting ecology of C. brachyotis in southern India.

The Lesser Dog-faced Fruit Bat Cynopterus brachyotis was found at higher elevations but since there is a paucity of reports on its distribution and habitat selection, an inventory was made at four locations in the Eastern and Western Ghats of southern India where the elevation ranged from 200–1,500 m. The C. brachyotis roosts were distributed between 600–1,500 m. Day roosts were found at an elevation of about 1,000m in Sirumalai and Yercaud Hill stations. Mist-netting studies, however, revealed that C. brachyotis was widely distributed at different elevations ranging from 600–1,500 m. Moreover, through a radio-telemetry study, we determined that the males foraged at shorter distances from the day roost, whereas the females commuted longer distances and used more than one foraging area. The male bats’ time of emergence is significantly less than females; in addition, males frequently return to their day-roost and made several short foraging flights spaced randomly throughout the night. These observations suggest that some type of territoriality is associated with their roost, which appears to be the basis of social organization in C. brachyotis. Overall, this study provides detailed information about the foraging and roosting ecology of C. brachyotis in southern India.

Monthly observations were made at a natural roosting site of Cynopterus sphinx, with a view to the behavior of males being observed over a period of one year. Here, we report seasonal, daily and inter-individual variation in three communicative behaviors engaged in by male bats. The frequency of male behaviors identified as scent-marking, vigorous wing-flapping and the making of an openwing gesture were found to vary seasonally, depending on the reproductive status of conspecific females in the study colony. The duration of scent-marking was markedly high during mating seasons, in comparison with wing-flapping and wing-gesturing. In mating seasons, the pattern to the daily variation in behavior correlated strongly with the gender of the responder present in the diurnal roost and/or colony. For instance, scent-marking and vigorous wing-flapping were more frequent during late-evening and early-morning hours, mostly when females were absent from the day roost, while male-male encounters were possible. In contrast, wing-gesturing was more frequent during morning and early-evening hours, when females were present in the day roost. The results from our study suggest that male scent-marking and wing-flapping are directed towards competitor males in the colony, with a view to resource-defense behavior being manifested. Furthermore, male wing-gesturing is predicted to be directed towards co-roosting females, with the aim in this case being for some form of social information to be communicated, particularly during the mating season. However, marginal inter-individual variation in the frequency of occurrence of behaviors between seasons was apparent, suggesting that these communicative behaviors could be tied to male-male competition in this species.

Background: The Oriental fruit bat genus Cynopterus, with several geographically overlapping species, presents an interesting case study to evaluate the evolutionary significance of coexistence versus isolation. We examined the morphological and genetic variability of congeneric fruit bats Cynopterus sphinx and C. brachyotis using 405 samples from two natural contact zones and 17 allopatric locations in the Indian subcontinent; and investigated the population differentiation patterns, evolutionary history, and the possibility of cryptic diversity in this species pair.Results: Analysis of microsatellites, cytochrome b gene sequences, and restriction digestion based genome-wide data revealed that C. sphinx and C. brachyotis do not hybridize in contact zones. However, cytochrome b gene sequences and genome-wide SNP data helped uncover a cryptic, hitherto unrecognized cynopterine lineage in northeastern India coexisting with C. sphinx. Further analyses of shared variation of SNPs using Patterson's D statistics suggest introgression between this lineage and C. sphinx. Multivariate analyses of morphology using genetically classified grouping confirmed substantial morphological overlap between C. sphinx and C. brachyotis, specifically in the high elevation contact zones in southern India.Conclusion: Our results uncover novel diversity and detect a pattern of genetic introgression in a cryptic radiation of bats, demonstrating the complicated nature of lineage diversification in this poorly understood taxonomic group. Our results highlight the importance of genome-wide data to study evolutionary processes of morphologically similar species pairs. Our approach represents a significant step forward in evolutionary research on young radiations of non-model species that may retain the ability of interspecific gene flow.

Sociality emerges when the benefits of group living outweigh its costs. While both males and females are capable of strong social ties, the evolutionary drivers for sociality and the benefits accrued maybe different for each sex. In this study, we investigate the differential reproductive success benefits of group membership that males and females might obtain in the promiscuous fruit bat Cynopterus sphinx. Individuals of this species live in flexible social groups called colonies. These colonies are labile and there is high turnover of individuals. However, colony males sire more offspring within the colony suggesting that being part of a colony may result in reproductive benefits for males. This also raises the possibility that long-term loyalty towards the colony may confer additional advantage in terms of higher reproductive success. We used ten seasons of genetic parentage data to estimate reproductive success and relatedness of individuals in the colony. We used recapture data to identify long and short-term residents in the colony as well as to obtain rates of recapture for males and females. Our results reveal that males have a significantly higher chance of becoming long-term residents (than females), and these long-term resident males gain twice the reproductive success compared to short-term resident males. We also observed that long-term resident females are related to each other and also achieve higher reproductive success than short-term resident females. In contrast, long-term resident males do not differ from short-term resident males in their levels of relatedness. Our results re-iterate the benefits of sociality even in species that are promiscuous and socially labile and possible benefits of maintaining a colony.

Different cognitive processes underlying voice identity perception in humans may have precursors in mammals. A perception of vocal signatures may govern individualised interactions in bats, which comprise species living in complex social structures and are nocturnal, fast-moving mammals. This paper investigates to what extent bats recognise, and discriminate between, individual voices and discusses acoustic features relevant for accomplishing these tasks. In spontaneous presentation and habituation–dishabituation experiments, we investigated how Megaderma lyra perceives and evaluates stimuli consisting of contact call series with individual-specific signatures from either social partners or unknown individuals. Spontaneous presentations of contact call stimuli from social partners or unknown individuals elicited strong, but comparable reactions. In the habituation–dishabituation experiments, bats dishabituated significantly to any new stimulus. However, reactions were less pronounced to a novel stimulus from the bat used for habituation than to stimuli from other bats, irrespective of familiarity, which provides evidence for identity discrimination. A model separately assessing the dissimilarity of stimuli in syllable frequencies, syllable durations and inter-call intervals relative to learned memory templates accounted for the behaviour of the bats. With respect to identity recognition, the spontaneous presentation experiments were not conclusive. However, the habituation–dishabituation experiments suggested that the bats recognised voices of social partners as the reaction to a re-habituation stimulus differed after a dishabituation stimulus from a social partner and an unknown bat.

Introduction Immediate responses towards emotional utterances in humans are determined by the acoustic structure and perceived relevance, i.e. salience, of the stimuli, and are controlled via a central feedback taking into account acoustic pre-experience. The present study explores whether the evaluation of stimulus salience in the acoustic communication of emotions is specifically human or has precursors in mammals. We created different pre-experiences by habituating bats ( Megaderma lyra ) to stimuli based on aggression, and response, calls from high or low intensity level agonistic interactions, respectively. Then we presented a test stimulus of opposite affect intensity of the same call type. We compared the modulation of response behaviour by affect intensity between the reciprocal experiments. Results For aggression call stimuli, the bats responded to the dishabituation stimuli independent of affect intensity, emphasising the attention-grabbing function of this call type. For response call stimuli, the bats responded to a high affect intensity test stimulus after experiencing stimuli of low affect intensity, but transferred habituation to a low affect intensity test stimulus after experiencing stimuli of high affect intensity. This transfer of habituation was not due to over-habituation as the bats responded to a frequency-shifted control stimulus. A direct comparison confirmed the asymmetric response behaviour in the reciprocal experiments. Conclusions Thus, the present study provides not only evidence for a discrimination of affect intensity, but also for an evaluation of stimulus salience, suggesting that basic assessment mechanisms involved in the perception of emotion are an ancestral trait in mammals.

Cryptic species are difficult to identify using morphological identification tools. They represent hitherto unknown biodiversity and their discovery helps formulate more efficient conservation management policies. In this study we assess intraspecific diversity of Rhinolophus rouxii and investigate the presence of cryptic lineages. We characterize acoustic, morphological and genetic differences between allopatric populations of this species in Southern India. Our results reveal the presence of two distinct acoustic lineages (80 and 90 kHz phonic types). Forearm length also differs significantly between the two phonic types. They share a sister taxa relationship and the average genetic distance between them is over 8 %. Phylogenetic reconstruction and the associated divergence time suggest an evolutionary history that correlates with a middle Miocene separation. We propose that these two phonic types be called sibling species and evolutionarily significant units (ESU) within the subgenus Indorhinolophus. We recommend a new name, R. indorouxii for the species representing the 90 kHz phonic type. This study reiterates our lack of accurate taxonomic knowledge of bats, and highlights the value in combining genetics with behavioral (phonic characterization) and morphological measurements in the discovery of cryptic species.

Cynopterus sphinx is a frugivorous bat also known to feed regularly on leaves. This raises the question whether microorganisms capable of digesting such a diet are present in the gut. In the present study cellulolytic and xylanolytic bacteria were isolated from the intestine of C. sphinx on Berg's agar medium containing carboxymethyl cellulose and xylan. The isolated cultivable cellulose and xylan degrading bacteria were characterized biochemically and identified to be Bacillus sp., Clostridium sp., Streptococcus sp., and Staphylococcus sp. Among the cultivable bacteria from the intestine of the insectivorous Hipposideros fulvus, which was used as a control, no cellulolytic and xylanolytic bacteria could be isolated. We hypothesize that leaves could be a carbohydrate source for bats. By isolating polysaccharide-degrading bacteria from the intestine of C. sphinx, we infer that they help in digestion of xylan and soluble cellulose in their diet.

Observations on mating behaviours and strategies guide our understanding of mating systems and variance in reproductive success. However, the presence of cryptic strategies often results in situations where social mating system is not reflective of genetic mating system. We present such a study of the genetic mating system of a harem‐forming bat Cynopterus sphinx where harems may not be true indicators of male reproductive success. This temporal study using data from six seasons on paternity reveals that social harem assemblages do not play a role in the mating system, and variance in male reproductive success is lower than expected assuming polygynous mating. Further, simulations reveal that the genetic mating system is statistically indistinguishable from promiscuity. Our results are in contrast to an earlier study that demonstrated high variance in male reproductive success. Although an outcome of behavioural mating patterns, standardized variance in male reproductive success (Im) affects the opportunity for sexual selection. To gain a better understanding of the evolutionary implications of promiscuity for mammals in general, we compared our estimates of Im and total opportunity for sexual selection (Im/If, where If is standardized variance in female reproductive success) with those of other known promiscuous species. We observed a broad range of Im/If values across known promiscuous species, indicating our poor understanding of the evolutionary implications of promiscuous mating.

In this study, we investigated the genetic social structure of a polygynous fruit bat, Cynopterus sphinx . We tested whether colonies of C. sphinx are substructured and if genetic relatedness among group members is non-random. Although we did not find statistical evidence of genetic structuring of harems within a colony, significant levels of inbreeding within colonies and social associations between related individuals were observed. The average pairwise relatedness was higher for females within a harem (average: 0.02) than within the colony (average: −0.03) ( p < 0.005). In most harems, the harem male was highly related to one harem female (with an average relatedness of 0.2). Further, statistical resampling suggested that this association is non-random, potentially suggesting mate selection. Although the average relatedness among males in colonies was zero, the range of relatedness (−0.43 to 0.49) was high. We conclude that colonies, to some extent are inbred units, comprising of both related and unrelated individuals, and that social associations might be kin based.

The Old World horseshoe bats are speculated to comprise of enormous cryptic diversity. The only Rhinolophid that has been studied with some detail in the subcontinent is the rufous horseshoe bat Rhinolophus rouxii. This bat has shown some extent of acoustic diversity between allopatric population of Peninsular India and Sri Lanka. As part of a long-term study of cryptic diversity we discovered a new phonic type of this bat in Southern India. Bats sampled from Yercaud, Tamil Nadu have principal frequencies above 90 kHz, whereas previously reported principal frequencies from bats of allopatric populations of Mahabaleswar and Srirangapattana are below 85 kHz. Interestingly, the difference between the principal frequencies of the Srirangapattana and Yercaud populations are more than those between Mahabaleswar and Srirangapattana populations, indicating the possible presence of cryptic lineages with in this species in Southern India.

Cynopterus sphinx is known to use polygynous mating system based on availability of resources, called resource defense polygyny. It is the primary mating strategy adopted by C. sphinx. In addition to such harem groups, a number of single adult males roost solitarily, nearer to the harems. Identifying the reasons behind the solitary roosting behaviour of such adult males is essential to further understand further the details of mating strategy in C. sphinx. In this context incomplete monopolization of harem females by harem males and nonharem male’s access to harem females is to be observed. The role of nonharem males as probable fathers has not been tested. In the present study, PCR based RAPD markers were used to assess the paternity of harem males and nearby nonharem males to the young born in the harems. A total of 30 arbitrary primers were used to assign the parentage of offsprings. Samples from a total of 651 individuals (41 harem males, 295 females, 267 suckling pups and 48 solitary males) from 41 harems (dry season 14 harems and wet season 27 harems) of C. sphinx were tested for their RAPD-PCR patterns. The molecular results suggest that the nonharem males also gain access to harem females and sire more offspring in July-August breeding season (wet) than March-April breeding season (dry). These results suggest that nonharem males are reproductively active and enjoy some reproductive success. Key words: Cynopterus sphinx, nonharem male, alternative strategy, mating system, paternity assessment, RAPD markers

We studied the breeding biology of Purple Swamphens (Porphyrio porphyrio poliocephalus) at Nainar Pond in Tirunelveli, South India from January 2003 to May 2004. Peak breeding activity occurred from the second week of January to the first week of March. Nests were built on thick floating vegetation closest to the bank of the pond. Nesting material consisted of whole plants, stems, and leaves of Eichhornia crassipes, Jussieua repens, Pistia stratiotes, Ipomoea aquatica, and Cyperus rotundas with E. crassipes being most preferred. Nest dimensions were variable. Clutch size varied from three to seven eggs with a mean (+/- SD) clutch size of 4.5 +/- 1.5 and a model clutch size of four eggs. Mean volume of all eggs was 32.3 +/- 3.5 cm(3). The length of the incubation period was estimated as 19.8 +/- 1.2 days. Nest and egg hatching success were estimated as 80.0% and 61.1%, respectively, while overall fledging success was 42.0%. Received 2 August 2008. Accepted 7 June 2009.

The study of parasites and their likely influence on optimal foraging and mate-selection in animals has attracted much attention in recent times. The possible effects of parasites on the host include the manipulation of host behaviour by parasites and the emergence of host behavioural adaptations for protecting against parasitism. Self-medication in wild animals is believed to be the behavioural adaptation evolved primarily against parasites and associated diseases. In this article, we have briefly reviewed some types of unusual behaviour observed in mammals, birds and insects which can be considered as self-medication.

Many mammals use multimodal sensory information to find their food in complex environments. We studied the roles of olfactory and visual cues in the foraging behaviour of Rousettus leschenaulti , a tongue-clicking megachiropteran bat. We conducted experiments by offering a whole fruit, mashed fruit without shape and an artificial fruit to R. leschenaulti in dim light as well as in total darkness. R. leschenaulti responded to whole guava fruit and mashed guava fruit even in total darkness, whereas, artificial fruit similar to real fruit in size, shape and structure was ignored even when illuminated. These results reveal that odour may act as the primary cue for R. leschenaulti in finding fruit.