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Ecological and Economic Importance of Bats (Order Chiroptera)  [PDF]
Mohammed Kasso,Mundanthra Balakrishnan
ISRN Biodiversity , 2013, DOI: 10.1155/2013/187415
Abstract: Order Chiroptera is the second most diverse and abundant order of mammals with great physiological and ecological diversity. They play important ecological roles as prey and predator, arthropod suppression, seed dispersal, pollination, material and nutrient distribution, and recycle. They have great advantage and disadvantage in economic terms. The economic benefits obtained from bats include biological pest control, plant pollination, seed dispersal, guano mining, bush meat and medicine, aesthetic and bat watching tourism, and education and research. Even though bats are among gentle animals providing many positive ecological and economic benefits, few species have negative effects. They cause damage on human, livestock, agricultural crops, building, and infrastructure. They also cause airplane strike, disease transmission, and contamination, and bite humans during self-defense. Bat populations appear to be declining presumably in response to human induced environmental stresses like habitat destruction and fragmentation, disturbance to caves, depletion of food resources, overhunting for bush meat and persecution, increased use of pesticides, infectious disease, and wind energy turbine. As bats are among the most overlooked in spite of their economical and ecological importance, their conservation is mandatory. 1. Introduction The order Chiroptera is the second most diverse among mammalian orders, which exhibits great physiological and ecological diversity [1]. They form one of the largest nonhuman aggregations and the most abundant groups of mammals when measured in numbers of individuals [2]. They evolved before 52 million years ago and diversified into more than 1,232 extant species [3]. They are small, with adult masses ranging from 2?g to 1?kg; although most living bats weigh less than 50?g as adults [4]. They have evolved into an incredibly rich diversity of roosting and feeding habits. Many species of bats roost during the day time in foliage, caves, rock crevices, hollows of trees, beneath exfoliating bark, and different man-made structures [2]. During night, they become active and forage on diverse food items like insects, nectar, fruits, seeds, frogs, fish, small mammals, and even blood [3]. The forelimb of a bat is modified into a wing with elongated finger bones joined together by a thin and large (85% of the total body surface area) membrane with rich blood flow [5]. Their wing is an unusual structure in mammals enabling for active unique powered flight. Skin covering the wings of bats not only constitutes a load-bearing area that enables
Ectoparasites of bats (Chiroptera, Furipteridae), with a description of a new species of Synthesiostrebla Townsend (Diptera, Streblidae) from Brazil
Graciolli, Gustavo;Azevedo, Alexsander Araújo;
Revista Brasileira de Entomologia , 2011, DOI: 10.1590/S0085-56262011005000054
Abstract: ectoparasites of bats (chiroptera, furipteridae), with a description of a new species of synthesiostrebla townsend (diptera, streblidae) from brazil. records of ectoparasites from furipterid bats are restricted to bat flies (streblidae). only three streblid species were known before this work: trichobius pallidus (curran, 1934), strebla wiedemanni kolenati, 1856, and synthesiostrebla amorphochili townsend, 1913. a second species of synthesiostrebla is described here, increasing the geographical distribution of the genus to east of the andes. synthesiostrebla cisandina sp. nov. was found on furipterus horrens (cuvier, 1828) in southeastern brazil. anterior parts of the body, wing, tergite 7, epiproct and male genitalia are illustrated, and a key to females for species of synthesiostrebla is provided.
Comparative morphology of the tongue in free-tailed bats (Chiroptera, Molossidae)
Gregorin, Renato;
Iheringia. Série Zoologia , 2003, DOI: 10.1590/S0073-47212003000200014
Abstract: descriptive and comparative studies on tongue of nineteen molossidae, one mystacinidae, and four vespertilionidae bats species were carried out. analysis was restricted to the external morphology, covering general shape of the tongue and its papillae. types of papillae and their distribution presented considerable intergeneric variation, considering the strictly insectivorous feeding habits of these bats. distribution of the data of tongue morphology is analyzed and compared with the phylogenetic schemes proposed previously and comments about evolutionary relationships among taxa were done.
Comparative morphology of the tongue in free-tailed bats (Chiroptera, Molossidae)  [cached]
Gregorin Renato
Iheringia. Série Zoologia , 2003,
Abstract: Descriptive and comparative studies on tongue of nineteen Molossidae, one Mystacinidae, and four Vespertilionidae bats species were carried out. Analysis was restricted to the external morphology, covering general shape of the tongue and its papillae. Types of papillae and their distribution presented considerable intergeneric variation, considering the strictly insectivorous feeding habits of these bats. Distribution of the data of tongue morphology is analyzed and compared with the phylogenetic schemes proposed previously and comments about evolutionary relationships among taxa were done.
Evolution of nectarivory in phyllostomid bats (Phyllostomidae Gray, 1825, Chiroptera: Mammalia)
Thomas Datzmann, Otto von Helversen, Frieder Mayer
BMC Evolutionary Biology , 2010, DOI: 10.1186/1471-2148-10-165
Abstract: Phylogenetic reconstructions, based on a concatenated nuclear-and mitochondrial data set, revealed a paraphyletic relationship of nectarivorous phyllostomid bats. Our phylogenetic reconstructions indicate that the nectarivorous genera Lonchophylla and Lionycteris are closer related to mainly frugivorous phyllostomids of the subfamilies Rhinophyllinae, Stenodermatinae, Carolliinae, and the insectivorous Glyphonycterinae rather than to nectarivorous bats of the Glossophaginae. This suggests an independent origin of morphological adaptations to a nectarivorous lifestyle within Lonchophyllinae and Glossophaginae. Molecular clock analysis revealed a relatively short time frame of about ten million years for the divergence of subfamilies.Our study provides strong support for diphyly of nectarivorous phyllostomids. This is remarkable, since their morphological adaptations to nutrition, like elongated rostrums and tongues, reduced teeth and the ability to use hovering flight while ingestion, closely resemble each other. However, more precise examinations of their tongues (e.g. type and structure of papillae and muscular innervation) revealed levels of difference in line with an independent evolution of nectarivory in these bats.The diversity of feeding specialization of phyllostomid bats are unique among all mammals [1-7]. They range from insect-to diverse vegetable-feeding strategies, as well as omnivory, carnivory, and even blood-feeding [8-16]. This ecological diversification is accompanied by morphological, behavioural and physiological adaptations [4,9,17-32]. A striking example is specialization for nectarivory, with several species feeding primarily on nectar. These bats have the ability to hover in front of a plant, while drinking nectar with their elongated and extensile tongues adorned with brush-like papillae and grooves for ingestion of nectar [3,26,29,30,33-37]. They digest and metabolize nectar and pollen quickly [32,38-44]. Phyllostomid bats represent the sec
Absent or Low Rate of Adult Neurogenesis in the Hippocampus of Bats (Chiroptera)  [PDF]
Irmgard Amrein, Dina K.N. Dechmann, York Winter, Hans-Peter Lipp
PLOS ONE , 2007, DOI: 10.1371/journal.pone.0000455
Abstract: Bats are the only flying mammals and have well developed navigation abilities for 3D-space. Even bats with comparatively small home ranges cover much larger territories than rodents, and long-distance migration by some species is unique among small mammals. Adult proliferation of neurons, i.e., adult neurogenesis, in the dentate gyrus of rodents is thought to play an important role in spatial memory and learning, as indicated by lesion studies and recordings of neurons active during spatial behavior. Assuming a role of adult neurogenesis in hippocampal function, one might expect high levels of adult neurogenesis in bats, particularly among fruit- and nectar-eating bats in need of excellent spatial working memory. The dentate gyrus of 12 tropical bat species was examined immunohistochemically, using multiple antibodies against proteins specific for proliferating cells (Ki-67, MCM2), and migrating and differentiating neurons (Doublecortin, NeuroD). Our data show a complete lack of hippocampal neurogenesis in nine of the species (Glossophaga soricina, Carollia perspicillata, Phyllostomus discolor, Nycteris macrotis, Nycteris thebaica, Hipposideros cyclops, Neoromicia rendalli, Pipistrellus guineensis, and Scotophilus leucogaster), while it was present at low levels in three species (Chaerephon pumila, Mops condylurus and Hipposideros caffer). Although not all antigens were recognized in all species, proliferation activity in the subventricular zone and rostral migratory stream was found in all species, confirming the appropriateness of our methods for detecting neurogenesis. The small variation of adult hippocampal neurogenesis within our sample of bats showed no indication of a correlation with phylogenetic relationship, foraging strategy, type of hunting habitat or diet. Our data indicate that the widely accepted notion of adult neurogenesis supporting spatial abilities needs to be considered carefully. Given their astonishing longevity, certain bat species may be useful subjects to compare adult neurogenesis with other long-living species, such as monkeys and humans, showing low rates of adult hippocampal neurogenesis.
Diet of two sympatric insectivores bats (Chiroptera: Vespertilionidae) in the Cerrado of Central Brazil
Aguiar, Ludmilla M. S.;Antonini, Yasmine;
Revista Brasileira de Zoologia , 2008, DOI: 10.1590/S0101-81752008000100005
Abstract: we examined food habits of vespertilionidae bats myotis nigricans (schinz, 1821) and eptesicus furinalis (d'orbigny, 1847) by fecal analysis in cerrado sensu stricto and gallery forests, within apa - gama-cabe?a-de-veado, brasília, distrito federal, brazil. out of 20 fecal samples collected, seven were of eptesicus furinalis and 13 of myotis nigricans. the diet of e. furinalis included six orders of insects: coleoptera (5/7 by items presence), lepidoptera and hymenoptera (3/7), diptera, hemiptera and homoptera (1/7). the diet of m. nigricans included all the main orders consumed by e. furinalis (6/13, 4/13, 4/13, 3/13, 1/13, and 4/13 respectively) and one other order: orthoptera (1/13). homoptera, diptera and orthoptera were collected only in bats captured in gallery forest. there is 80% of overlap in the diet of these two species. predation on species of scarabeidae, hesperiidae, sphingidae and saturniidae families confirms bats potential as biological control agents of pests in agricultural ecosystems.
Movements of bats (Mammalia, Chiroptera) in Atlantic Forest remnants in southern Brazil
Bianconi, Gledson V.;Mikich, Sandra B.;Pedro, Wagner A.;
Revista Brasileira de Zoologia , 2006, DOI: 10.1590/S0101-81752006000400030
Abstract: we used mark and recapture techniques to evaluate movements of bats within and between three brazilian forest remnants. we captured bats with mist-nets in four 1 ha plots representing different degrees of isolation of riparian (two plots) and submontane (two plots) forests between july 2002 and june 2003. using numbered aluminium tags, we marked 635 bats of seven species and 54 individuals of six species were recaptured. overall, we recaptured carollia perspicillata (linnaeus, 1758) (short-tailed fruit bat) most frequently, especially in plots where they were banded in the riparian forest plots. these results suggest that this bat has restricted feeding areas, which are probably determined by the abundance of piper linnaeus (piperaceae), its preferred food item. in contrast, species of the genus artibeus leach, 1821 exhibited few recaptures, suggesting high mobility and larger feeding areas. in fact artibeus seems to use more of the forest remnants in their search for food, especially ficus linnaeus (moraceae), the preferred food of this bat. our results suggest that even small forest isolates are valuable for the maintenance of some bat species because they offer many of the resources they need or because they are spatially distributed in a pattern that allows use of the entire landscape.
Immunocytochemical study of gastrintestinal endocrine cells in insectivorous bats (Mammalia: Chiroptera)
Santos, CM.;Nascimento, AA.;Peracchi, AL.;Sales, A.;Mikalauskas, JS.;Gouveia, SF.;
Brazilian Journal of Biology , 2008, DOI: 10.1590/S1519-69842008000300026
Abstract: the regional distribution and relative frequency of endocrine cells in the stomach and intestine of phyllostomidae: lonchorhina aurita and molossidae: molossus molossus bats were studied immunohistochemically. three types of immunoreactive (ir) endocrine cells - to serotonin (5-ht), gastrin (gas) and enteroglucagon (gluc) - were found in the gastric mucosa and four types of ir cells were identified in the intestinal mucosa. this study showed an interespecfic difference in the regional distribution and relative frequency of endocrine cells in the chiropteran alimentary tract.
Genetic analysis on three South Indian sympatric hipposiderid bats (Chiroptera, Hipposideridae)  [PDF]
C. Kanagaraj,G. Marimuthu,K. Emmanuvel Rajan
Animal Biodiversity and Conservation , 2010,
Abstract: In mitochondrial DNA, variations in the sequence of 16S rRNA region were analyzed to infer the genetic relationship and population history of three sympatric hipposiderid bats, Hipposideros speoris, H. fulvus and H. ater. Based on the DNA sequence data, we observed relatively lower haplotype and higher nucleotide diversity in H.speoris than in the other two species. The pairwise comparisons of the genetic divergence inferred a genetic relationship between the three hipposiderid bats. We used haplotype sequences to construct a phylogenetic tree. Maximum parsimony and Bayesian inference analysis generated a tree with similar topology. H. fulvus and H. ater formed one cluster and H. speoris formed another cluster. Analysis of the demographic history of populations using Jajima’s D test revealed past changes in populations. Comparison of the observed distributionof pairwise differences in the nucleotides with expected sudden expansion model accepts for H. fulvus and H. ater but not for H. speoris populations.
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