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1

Jak uskrzydlały się ssaki

100%
Simmons N. B.
Świat Nauki
|
2009
|
nr 01
2

Morphological specializations of Cheiromeles (naked bulldog bats; Molossidae) and their possible role in quadrupedal locomotion

72%
Schutt,Jr. W. A., Simmons N. B.
Acta Chiropterologica
|
2001
|
tom 03
|
nr 2
Two molossids, Cheiromeles torquatus and C. parvidens, display a number of morphological characteristics that appear unique among Chiroptera. In this study, adult specimens of both species (fluid-preserved and skeletons) were examined using a dissecting microscope and camera lucida. Several unique morphological features are described in detail for the first time with comments on their possible functions. These include a hallux (digit I) that is positioned at a right angle to digits II-V, a calcar that is bound to m. gastrocnemius, and a modified m. tensor plagiopatagii which appears to function like a drawstring to close a pair of subaxillary 'pouches'. The function of these structures and additional characteristics of the limbs appear related to terrestrial and arboreal locomotion exhibited by these bats.
3

Morphological diagnoses of higher-level phyllostomid taxa (Chiroptera: Phyllostomidae)

58%
Cirranello A., Simmons N. B., Solari S., Baker R. J.
Acta Chiropterologica
|
2016
|
tom 18
|
nr 1
Phyllostomidae (New World leaf-nosed bats), the second most speciose chiropteran family, is one of the best-known and wellstudied chiropteran groups. Due to the ecological and morphological diversity of this family, comparative studies of phyllostomids abound in the literature, and numerous systematic and phylogenetic analyses have been published. Unfortunately, many of these studies have reached different conclusions concerning phyllostomid relationships, and have proposed different classification schemes. This has led to confusion, and highlighted the need for a well-supported and stable classification of the family, particularly at the level of subfamilies and tribes, areas of the greatest controversy. The goal of this paper is to provide morphological diagnoses of higher-level taxa (subtribes, tribes, and subfamilies). Herein we provide morphological diagnoses for 11 subfamilies (Macrotinae, Micronycterinae, Desmodontinae, Lonchorhininae, Phyllostominae, Glyphonycterinae, Glossophaginae, Lonchophyllinae, Carollinae, Rhinophyllinae, and Stenodermatinae), 12 tribes (Desmodontini, Diphyllini, Macrophyllini, Phyllostomini, Vampyrini, Choeronycterini, Glossophagini, Brachyphyllini, Lonchophyllini, Hsunycterini, Sturnirini, and Stenodermatini), and nine subtribes (Anourina, Choeronycterina, Brachyphyllina, Phyllonycterina, Vampyressina, Enchisthenina, Ectophyllina, Artibeina, and Stenodermatina).
4

The systematic position of Pteropus leucopterus and its bearing on the monophyly and relationships of Pteropus (Chiroptera: Pteropodidae)

58%
Giannini N. P., Almeida F. C., Simmons N. B., Helgen K. M.
Acta Chiropterologica
|
2008
|
tom 10
|
nr 1
Pteropus is the most speciose genus in Pteropodidae, currently comprising 65 species in 18 species groups. Here we examine whether Pteropus as currently understood is monophyletic. We sequenced three nuclear genes (RAG-1, RAG-2 and vWF) totalling c. 3.0 kbp from 18 species of Pteropus representing 12 species groups, plus Acerodon celebensis and megachiropteran outgroups representing all other subfamilies and tribes. Separate and combined parsimony and maximum likelihood analyses recovered a clade containing Acerodon as sister to all Pteropus species to the exclusion of the Philippine endemic taxon ‘P. leucopterus’, rendering Pteropus paraphyletic. We propose the revalidation of Desmalopex Miller, 1907, an available generic name for leucopterus, adopting the name combination Desmalopex leucopterus (Temminck, 1853). We discuss implications of this result and anticipate further modifications of the classification of Pteropus.
5

The evolutionary history of the African fruit bats (Chiroptera: Pteropodidae)

58%
Almeida F. C., Giannini N. P., Simmons N. B.
Acta Chiropterologica
|
2016
|
tom 18
|
nr 1
Bats of the family Pteropodidae, also known as megabats or Old World fruit bats, are widely distributed in tropical areas of Africa, Asia, and Oceania. Of 45 genera in the family, 12 are endemic to the Afro-tropical region and two others have representative species on the African continent. African megabats inhabit wooded habitats and are nearly ubiquitous on the mainland and nearby islands with the exception of desert areas. Some species have been implicated as possible reservoirs of the Ebola Zaire virus. We studied the phylogenetic relationships of mainland African megabats using both mitochondrial and nuclear loci in separate and combined analyses. The phylogenetic trees obtained showed four main African clades: Eidolon, Scotonycterini (including two genera), African Rousettus (three species), and the previously identified ‘endemic African clade’ (nine genera). The latter three lineages form a clade that also includes the Asian species of Rousettus and the Asian genus Eonycteris; Eidolon does not show close relationships to other African genera, instead nesting elsewhere in the megabat tree. Although our results confirm many of the conclusions of previous studies, they challenge the taxonomic status and placement of Epomops dobsonii and Micropteropus, and provide evidence indicating that a new classification at subfamilial and tribal levels is highly desirable. The principal clades we detected represent four independent colonizations of Africa from most probably Asian ancestors. Estimates of divergence dates suggest that these events occurred in different periods and that although local diversification appears to have started in the late Miocene, the more extensive diversification that produced the modern fauna occurred much later, in the Pleistocene.
6

The bat fauna of the Saul region, French Guiana

58%
Simmons N. B., Voss R. S., Peckham H. C.
Acta Chiropterologica
|
2000
|
tom 02
|
nr 1
The area around Saül, French Guiana, offers easy access to undisturbed lowland primary rainforest as well as cleared and disturbed areas near human settlements. Fieldwork conducted at Les Eaux Claires (a homestead 7 km N of Saül) in July and August 1999 resulted in capture of 40 species ofbats, including 17 species previously unknown from the area. Together with records from prior studies, this brings the known bat fauna of the Saül region to 54 species. Consideration of collecting methods and comparisons with faunas from elsewhere in French Guiana suggest that the present faunal list is strongly biased in favor of understory gleaners and frugivores (members of the phyllostomid subfamilies Phyllostominae, Carolliinae, and Stenodermatinae). During our sampling period, bat capture rates were higher in modified habitats (manmade clearings, secondary growth, and disturbed forest) than in primary forest, but species accumulation rates were higher in primary forest than in modified habitats. Phyllostomines accounted for the majority of captures in primary forest, while stenoder- matines accounted for most captures in modified habitats. Analysis of faunal relationships indicates that the Saül bat list is most similar to those from the lower Arataye region and neighboring sites in French Guiana. French Guianan bat faunas cluster with those from other sites in the Guiana subregion of Amazonia, and are distinct from those of southeastern and western Amazonian localities.
7

Low levels of population structure among geographically distant populations of Pteropus vampyrus (Chiroptera: Pteropodidae)

51%
Tsang S. M., Wiantoro S., Veluz M. J., Simmons N. B., Lohman D. J.
Acta Chiropterologica
|
2018
|
tom 20
|
nr 1
Pteropus vampyrus, the largest bat in the world, has a broad geographic range covering much of Southeast Asia. The wide distribution of P. vampyrus and its ability to cross oceanic expanses makes management of this threatened species an international concern. Pteropus vampyrus is an essential seed disperser and pollinator of rain forest trees, many of which are ecologically and economically important. Understanding population dynamics of P. vampyrus is thus critical to addressing conservation issues and global health concerns. We used phylogenetic inference and population genetic indices to infer past gene flow between populations of P. vampyrus throughout most of the species' range. Population genetic parameters indicate low levels of nucleotide variability with high haplotype diversity across its range, implying a demographic scenario of recent population expansion after a bottleneck. Subspecies were not found to be monophyletic from the genetic data, which may reflect some level of genetic variation on even shallower time scales. The low level of population genetic structure throughout the species range is not necessarily surprising given its high vagility and seasonal migratory behavior. However, it cannot be entirely excluded that these results may reflect historical connectivity or lineage sorting issues rather than more recent persistent gene flow. These findings highlight the need for international cooperation and monitoring to ensure persistence of populations and to create a species management plan that can protect the species throughout its range. Increased genetic sampling is needed to ascertain P. vampyrus' commonly used dispersal routes and to assess the possibility of asymmetric gene flow among populations.
8

Conjoined twins in a wild bat: a case report

44%
Urban D. J., Sorensen D. W., Maier J. A., Fenton M. B., Simmons N. B., Cooper L. N., Sears K. E.
Acta Chiropterologica
|
2015
|
tom 17
|
nr 1
There are numerous records of conjoined twinning in humans and domesticated animals, but many fewer for wild animals because of the early death of conjoined twins. We here describe the incidental discovery and skeletal anatomy of a wild-caught bat fetus with two heads. To our knowledge, this is only the second conjoined bat fetus described, and the first conjoined Artibeus phaeotis. We also revisit the anatomy of the first conjoined bat that was described, a stillborn Eptesicus fuscus.
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