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Full-Text Articles in Life Sciences

Life History, Sexual Dimorphism And 'Ornamental' Feathers In The Mesozoic Bird Confuciusornis Sanctus., Winfried S. Peters, Dieter Stefan Peters Sep 2009

Life History, Sexual Dimorphism And 'Ornamental' Feathers In The Mesozoic Bird Confuciusornis Sanctus., Winfried S. Peters, Dieter Stefan Peters

Winfried S. Peters

The life history of Confuciusornis sanctus is controversial. Recently, the species’ body size spectrum was claimed to contradict osteohistological evidence for a rapid, bird-like development. Moreover, sexual size dimorphism was rejected as an explanation for the observed bimodal size distribution since the presence of elongated rectrices, an assumed ‘male’ trait, was uncorrelated with size. However, this interpretation (i) fails to explain the size spectrum of C. sanctus which is trimodal rather than bimodal, (ii) requires implausible neonate masses and (iii) is not supported by analogy with sexual dimorphisms in modern birds, in which elongated central rectrices are mostly sex-independent. Available …


Preliminary Analysis Of The Ecology And Geography Of The Asian Nuthatches (Aves: Sittidae), Shaily Menon, Zafar-Ul Islam, Jorge Soberon, A. Townsend Peterson Aug 2009

Preliminary Analysis Of The Ecology And Geography Of The Asian Nuthatches (Aves: Sittidae), Shaily Menon, Zafar-Ul Islam, Jorge Soberon, A. Townsend Peterson

Shaily Menon

We explored distributions of Asian nuthatch species in ecological and geographic space using ecological niche modeling based on occurrence data associated with specimens and observations. Nuthatches represent a well-defined clade occurring throughout the Northern Hemisphere, but are most diverse in southern Asia where 15 of the 24 species occur and where the lineage is believed to have evolved. Species richness was focused in a narrow east-west band corresponding to the forested parts of the Himalayas with a maximum number of nine species predicted present in these foci. The distributional predictions have a mid-elevation focus with highest species diversity between 1,000 …


Road-Killed Bats, Highway Design, And The Commuting Ecology Of Bats, Amy L. Russell, Calvin M. Butchkoski, Leslie Saidak, Gary F. Mccracken Jun 2009

Road-Killed Bats, Highway Design, And The Commuting Ecology Of Bats, Amy L. Russell, Calvin M. Butchkoski, Leslie Saidak, Gary F. Mccracken

Amy L. Russell

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 …


Two New Species Of Cave-Dwelling Beetles Trechus Clairville Of Fulvus-Group In Portugal, Ana Reboleira, Fernando Gonçalves, Artur Serrano Apr 2009

Two New Species Of Cave-Dwelling Beetles Trechus Clairville Of Fulvus-Group In Portugal, Ana Reboleira, Fernando Gonçalves, Artur Serrano

Ana Sofia P.S. Reboleira

Two new cave-dwelling ground beetle species, Trechus gamae sp. n. and Trechus lunai sp. n., from Portugal, are described. The new species are included in the Trechus fulvus-group by their morphological characters. The work provides diagnostic characters in particular those of the structure of male genitalia, and the distribution of the hypogean species of the fulvus -group at the Estremenho Karstic Massif is mapped. Some comments on the seasonal activity of T. gamae sp. n. are also given. An identification key to the males of the T. fulvus-group species from the Estremenho Karstic Massif is presented, and biogeographical comments are …


Skeletal Advance And Arrest In Giant Non-Metamorphosing African Clawed Frog Tadpoles (Xenopus Laevis: Daudin), Ryan Kerney, Richard Wassersug, Brian Hall Dec 2008

Skeletal Advance And Arrest In Giant Non-Metamorphosing African Clawed Frog Tadpoles (Xenopus Laevis: Daudin), Ryan Kerney, Richard Wassersug, Brian Hall

Ryan Kerney

This study examines the skeletons of giant non-metamorphosing (GNM) Xenopus laevis tadpoles, which arrest their development indefinitely before metamorphosis, and grow to excessively large sizes in the absence of detectable thyroid glands. Cartilage growth is isometric; however, chondrocyte size is smaller in GNM tadpoles than in controls. Most cartilages stain weakly with alcian blue, and several cartilages are calcified (unlike con- trols). However, cartilages subjacent to periosteum-derived bone retain strong affinities for alcian blue, indicat- ing a role for periosteum-derived bone in the retention of glycosaminoglycans during protracted larval growth. Bone formation in the head, limb, and axial skeletons is …


Multiple Colonisations Of The Western Indian Ocean By Pteropus Fruit Bats (Megachiroptera: Pteropodidae): The Furthest Islands Were Colonised First, John O'Brien, Carol Mariani, Link Olson, Amy L. Russell, Ludovic Say, Anne D. Yoder, Tom J. Hayden Dec 2008

Multiple Colonisations Of The Western Indian Ocean By Pteropus Fruit Bats (Megachiroptera: Pteropodidae): The Furthest Islands Were Colonised First, John O'Brien, Carol Mariani, Link Olson, Amy L. Russell, Ludovic Say, Anne D. Yoder, Tom J. Hayden

Amy L. Russell

We investigate the genetic relationships between purported island species of Pteropus fruit bat (Megachi- roptera) 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, sug- gesting instead that many of the western Indian Ocean islands harbour ‘races’ of P. giganteus from main- land India. Our results strongly argue against a single colonisation event from mainland Asia. Evidence is presented for three colonisation events; the first to …


Reintroduction Of The Chinese Tiger, Philip J. Nyhus, Urs Breitenmoser, Ron Tilson Dec 2008

Reintroduction Of The Chinese Tiger, Philip J. Nyhus, Urs Breitenmoser, Ron Tilson

Philip J. Nyhus

No abstract provided.


Anuran Captured In Pitfall Traps In Three Agrossystem In Northwestern São Paulo State, Brazil, Rodrigo Souza Santos Rss Dec 2008

Anuran Captured In Pitfall Traps In Three Agrossystem In Northwestern São Paulo State, Brazil, Rodrigo Souza Santos Rss

Rodrigo Souza Santos RSS

Although it is generally assumed that agriculture negatively influences amphibian populations, few studies on the effects of agricultural cultivations on neotropical anuran have been conducted. As a contribution to the knowledge about anuran in agriculture, the present study sought to identify the anuran species present in three different agrossystems. We used data from anurans captured in pitfall traps initially proposed for a survey of harvestmen fauna in three agrossystems (corn, soybean, and rubber tree). Four anuran species found in the pitfall traps belong to two Families: Leptodactylidae: Leptodactulus fuscus and L. mystacinus; and Leiuperidae: Eupemphix nattereri and Physalaemus cuvieri. In …