\u3ci\u3eCynopterus sphinx\u3c/i\u3e

Order Chiroptera, Family Pteropodidae, Subfamily Pteropodinae, Tribe Cynopterini, Subtribe Cynopterina, Genus Cynopterus. Five species are recognized: C. brachyotis, C. horsfieldi, C. nusatenggara, C. sphinx, and C. titthaecheileus (Koopman, 1993). A key to the species is given in Lekagul and McNeely (1977)

Genetic Consequences of Polygyny and Social Structure in an Indian Fruit Bat, \u3ci\u3eCynopterus sphinx\u3c/i\u3e. II. Variance in Male Mating Success and Effective Population Size

Variance in reproductive success is a primary determinant of genetically effective population size (Ne), and thus has important implications for the role of genetic drift in the evolutionary dynamics of animal taxa characterized by polygynous mating systems. Here we report the results of a study designed to test the hypothesis that polygynous mating results in significantly reduced Ne in an age-structured population. This hypothesis was tested in a natural population of a harem-forming fruit bat, Cynopterus sphinx (Chiroptera: Pteropodidae), in western India. The influence of the mating system on the ratio of variance Ne to adult census number (N) was assessed using a mathematical model designed for age-structured populations that incorporated demographic and genetic data. Male mating success was assessed by means of direct and indirect paternity analysis using 10-locus microsatellite genotypes of adults and progeny from two consecutive breeding periods (n = 431 individually marked bats). Combined results from both analyses were used to infer the effective number of male parents in each breeding period. The relative proportion of successfully reproducing males and the size distribution of paternal sibships comprising each offspring cohort revealed an extremely high within-season variance in male mating success (up to 9.2 times higher than Poisson expectation). The resultant estimate of Ne/N for the C. sphinx study population was 0.42. As a result of polygynous mating, the predicted rate of drift (½Ne per generation) was 17.6% higher than expected from a Poisson distribution of male mating success. However, the estimated Ne/N was well within the 0.25–0.75 range expected for age-structured populations under normal demographic conditions. The life-history schedule of C. sphinx is characterized by a disproportionately short sexual maturation period scaled to adult life span. Consequently, the influence of polygynous mating on Ne/N is mitigated by the extensive overlap of generations. In C. sphinx, turnover of breeding males between seasons ensures a broader sampling of the adult male gamete pool than expected from the variance in mating success within a single breeding period

Social structure of a polygynous tent-making bat, \u3ci\u3eCynopterus sphinx\u3c/i\u3e (Megachiroptera)

The social structure of an Old World tent-making bat Cynopterus sphinx (Megachiroptera), was investigated in western India. A combination of census and mark–recapture data over 2 years (1996–98) was used to infer the form of the mating system, compositional stability of social groups and mode of new social group formation. The breeding population of C. sphinx was subdivided into diurnal roosting colonies, each of which contained one to five discrete roosting groups and often one or more solitary bats in adjacent roosts. Bats most frequently roosted in stem tents constructed in the flower/fruit clusters of the kitul palm Caryota urens. Temporal variation in social structure was assessed using visual census data for a subset of the study population over 3 years (1995– 98) spanning six consecutive reproductive periods. The sex and age composition of diurnal roosting groups indicated a polygynous harem-forming mode of social organization, as groups invariably contained a single adult male, 1–37 reproductive females and their dependent young (n = 33 harems). Harem size averaged 6.1 adults in the wet season (n = 19, SD = 3.5) and 13.6 adults in the dry season (n = 14, SD = 8.5). The same harem social configuration was maintained year-round, despite a high degree of synchrony and seasonality in the timing of reproduction. Juveniles of both sexes dispersed after weaning and sexually immature bats were never present in harems at the time of parturition. Adult females often remained associated as roostmates from one parturition period to the next, and group cohesion was unaffected by turnover of harem males. Adult females frequently transferred among roosts within the same colony, and harems underwent periodic fissions and fusions. The founding of new harems most often resulted from the fissioning of previously cohesive harems within the same colony. However, some harems contained disproportionate numbers of yearling females, indicating that new groups are also founded by nulliparous females of the same age cohort. A significant degree of heterogeneity in age composition among harems was revealed in the 1998 dry season, but was unrelated to age-stratification of tent roosts. Although formation of new harems may be non-random with respect to age composition of the founders, founding events are not restricted to newly created tents and often involve recolonization of previously occupied roosts

An antibody-based microarray assay for small RNA detection

Detection of RNAs on microarrays is rapidly becoming a standard approach for molecular biologists. However, current methods frequently discriminate against structured and/or small RNA species. Here we present an approach that bypasses these problems. Unmodified RNA is hybridized directly to DNA microarrays and detected with the high-affinity, nucleotide sequence-independent, DNA/RNA hybrid-specific mouse monoclonal antibody S9.6. Subsequent reactions with a fluorescently-labeled anti-mouse IgG antibody or biotin-labeled anti-mouse IgG together with fluorescently labeled streptavidin produces a signal that can be measured in a standard microarray scanner. The antibody-based method was able to detect low abundance small RNAs of Escherichia coli much more efficiently than the commonly-used cDNA-based method. A specific small RNA was detected in amounts of 0.25 fmol (i.e. concentration of 10 pM in a 25 µl reaction). The method is an efficient, robust and inexpensive technique that allows quantitative analysis of gene expression and does not discriminate against short or structured RNAs

Modern Michelson-Morley experiment using cryogenic optical resonators

We report on a new test of Lorentz invariance performed by comparing the resonance frequencies of two orthogonal cryogenic optical resonators subject to Earth's rotation over 1 year. For a possible anisotropy of the speed of light c, we obtain 2.6 +/- 1.7 parts in 10^15. Within the Robertson-Mansouri-Sexl test theory, this implies an isotropy violation parameter beta - delta - 1/2 of -2.2 +/- 1.5 parts in 10^9, about three times lower than the best previous result. Within the general extension of the standard model of particle physics, we extract limits on 7 parameters at accuracies down to a part in 10^15, improving the best previous result by about two orders of magnitude

Evolutionary Dynamics of the Short-Nosed Fruit Bat, \u3ci\u3eCynopterus sphinx \u3c/i\u3e (Pteropodidae): Inferences from the Spatial Scale of Genetic and Phenotypic Differentiation

We report the results of a population-genetic study of the short-nosed fruit bat, Cynopterus sphinx (Pteropodidae). The purpose of our study was to assess the relative importance of drift, gene flow, and spatially varying selection in shaping patterns of genetic and phenotypic variation across a latitudinal climatic gradient in peninsular India. At a microgeographic scale, polygynous mating resulted in a substantial reduction of effective population size. However, at a macrogeographic scale, rates of migration were sufficiently high to prevent a pronounced degree of stochastic differentiation via drift. Spatial analysis of genetic and phenotypic differentiation revealed that clinal variation in body size of C. sphinx cannot be explained by a neutral model of isolation by distance. The geographic patterning of morphometric variation is most likely attributable to spatially varying selection and/or the direct influence of latitudinally ordered environmental effects. The combined analysis of genetic and phenotypic variation indicates that recognized subspecies of C. sphinx in peninsular India represent arbitrary subdivisions of a continuous spectrum of clinal size variation