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The Amphibian and Reptile Species of Igneada (Kirklareli) and its Vicinity  [PDF]
?etin Ilgaz,Yusuf Kumlutas
Pakistan Journal of Biological Sciences , 2005,
Abstract: This study was aimed to describe the herpetofauna of Igneada (Kirklareli) and its vicinity. In the research area, 113 specimens belonging to 14 species from 8 amphibian and reptile families were determined. Two of these anurans, 1 is a tortoise, 1 is a turtles, 7 are lizards and 2 are snakes. Darevskia praticola pontica specimens collected in the research area were investigated according to pholidosis characters and morphometric measurements and the known range of this subspecies was also extended.
The Maryland Amphibian and Reptile Atlas: A Volunteer-Based Distributional Survey  [PDF]
Heather R. Cunningham,Charles A. Davis,Christopher W. Swarth,Glenn D. Therres
International Journal of Zoology , 2012, DOI: 10.1155/2012/348653
Abstract: Declines of amphibian and reptile populations are well documented. Yet a lack of understanding of their distribution may hinder conservation planning for these species. The Maryland Amphibian and Reptile Atlas project (MARA) was launched in 2010. This five-year, citizen science project will document the distribution of the 93 amphibian and reptile species in Maryland. During the 2010 and 2011 field seasons, 488 registered MARA volunteers collected 13,919 occurrence records that document 85 of Maryland’s amphibian and reptile species, including 19 frog, 20 salamander, five lizard, 25 snake, and 16 turtle species. Thirteen of these species are of conservation concern in Maryland. The MARA will establish a baseline by which future changes in the distribution of populations of native herpetofauna can be assessed as well as provide information for immediate management actions for rare and threatened species. As a citizen science project it has the added benefit of educating citizens about native amphibian and reptile diversity and its ecological benefits—an important step in creating an informed society that actively participates in the long-term conservation of Maryland’s nature heritage. 1. Introduction Amphibian and reptile species are among the most threatened groups of vertebrate animals [1, 2]. Factors that lead to population declines are habitat alteration and loss, invasive species, disease, environmental pollution, commercial collection, and climate change [1, 3]. The lack of thorough understanding of regional distribution patterns of amphibian and reptile populations can limit our ability to predict how species will respond to these factors [4]. An additional challenge to the protection and conservation of amphibian and reptile species (also called herps) is the overall negative perception by the public towards these organisms [5]. There is a pervasive attitude that these organisms are unimportant [5]. However citizen science projects, defined as projects where citizens participate in scientific research [5], have the potential to advance the protection of amphibian and reptile species. Specifically, citizen science-based atlas projects can efficiently assemble distribution information across large spatial scales while increasing environmental awareness in the general public about the ecological importance of herpetofauna. Through participation in atlas projects citizens play an important role in the long-term protection and conservation of amphibians and reptiles. Currently 93 native species of amphibians and reptiles occur in Maryland (20
DNA in Amphibian and Reptile Venom Permits Access to Genomes Without Specimen Sacrifice
Hang Fai Kwok, Tianbao Chen, Craig Ivanyi and Chris Shaw
Genomics Insights , 2012,
Abstract: Amphibian defensive skin secretions and reptile venoms are rich sources of bioactive peptides with potential pharmacological/pharmaceutical applications. As amphibian and reptile populations are in rapid global decline, our research group has been developing analytical methods that permit generation of robust molecular data from non-invasive skin secretion samples and venom samples. While previously we have demonstrated that parallel proteome and venom gland transcriptome analyses can be performed on such samples, here we report the presence of DNA that facilitates the more widely-used applications of gene sequencing, such as molecular phylogenetics, in a non-invasive manner that circumvents specimen sacrifice. From this “surrogate” tissue, we acquired partial 12S and 16S rRNA gene sequences that are presented for illustration purposes. Thus from a single sample of amphibian skin secretion and reptile venom, robust and complementary proteome, transcriptome and genome data can be generated for applications in diverse scientific disciplines.
On the nonexistence of k-reptile tetrahedra  [PDF]
Ji?í Matou?ek,Zuzana Safernová
Mathematics , 2010,
Abstract: A d-dimensional simplex S is called a k-reptile if it can be tiled without overlaps by simplices S_1,S_2,...,S_k that are all congruent and similar to S. For d=2, k-reptile simplices (triangles) exist for many values of k and they have been completely characterized by Snover, Waiveris, and Williams. On the other hand, for d > 2, only one construction of k-reptile simplices is known, the Hill simplices, and it provides only k of the form m^d, m=2,3,.... We prove that for d=3, k-reptile simplices (tetrahedra) exist only for k=m^3. This partially confirms a conjecture of Hertel, asserting that the only k-reptile tetrahedra are the Hill tetrahedra. Our research has been motivated by the problem of probabilistic packet marking in theoretical computer science, introduced by Adler in 2002.
No acute tetrahedron is an 8-reptile  [PDF]
Herman Haverkort
Computer Science , 2015,
Abstract: An $r$-gentiling is a dissection of a shape into $r \geq 2$ parts which are all similar to the original shape. An $r$-reptiling is an $r$-gentiling of which all parts are mutually congruent. This article shows that no acute tetrahedron is an $r$-gentile or $r$-reptile for any $r < 9$, by showing that no acute spherical diangle can be dissected into less than nine acute spherical triangles.
Phylogenetically-Informed Priorities for Amphibian Conservation  [PDF]
Nick J. B. Isaac, David W. Redding, Helen M. Meredith, Kamran Safi
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0043912
Abstract: The amphibian decline and extinction crisis demands urgent action to prevent further large numbers of species extinctions. Lists of priority species for conservation, based on a combination of species’ threat status and unique contribution to phylogenetic diversity, are one tool for the direction and catalyzation of conservation action. We describe the construction of a near-complete species-level phylogeny of 5713 amphibian species, which we use to create a list of evolutionarily distinct and globally endangered species (EDGE list) for the entire class Amphibia. We present sensitivity analyses to test the robustness of our priority list to uncertainty in species’ phylogenetic position and threat status. We find that both sources of uncertainty have only minor impacts on our ‘top 100‘ list of priority species, indicating the robustness of the approach. By contrast, our analyses suggest that a large number of Data Deficient species are likely to be high priorities for conservation action from the perspective of their contribution to the evolutionary history.
Mapping the terrestrial reptile distributions in Oman and the United Arab Emirates  [cached]
Andrew Gardner
ZooKeys , 2009, DOI: 10.3897/zookeys.31.133
Abstract: The terrestrial reptile fauna of Oman and the United Arab Emirates is rich, with at least 79 species of lizards and snakes and a single species of worm lizard. However, to date there have been no accurate maps published of their distribution ranges, and distribution data relies on scattered museum specimen localities and published accounts. Considerable numbers of locality data points do exist, collected by visting and resident herpetologists, and more recently, from ecologists working on surveys for environmental impact assessments and biodiversity action plans. These data are invaluable, as amongst other uses, they can assist conservation planning and management, and will eventually document changes in distributions over time. This is especially true where there has been extensive habitat loss and degradation due to urbanisation and development activities. Data have been collected from museum records, published accounts and unpublished data from a variety of sources, including many records made by the author over the last 20 years, with the aim of producing an atlas of species distributions. The number of records is now approaching 5.000, giving sufficient coverage to produce maps that are useful for a variety of applications. Examples are discussed, including endangered and endemic species, snakes of medical importance and species of potential interest in ecological and evolutionary studies.
Density-Dependent Effects of Amphibian Prey on the Growth and Survival of an Endangered Giant Water Bug  [PDF]
Shin-ya Ohba
Insects , 2011, DOI: 10.3390/insects2040435
Abstract: Amphibian predator–insect prey relationships are common in terrestrial habitats, but amphibian larvae are preyed upon by a variety of aquatic hemipterans in aquatic habitats. This paper suggests that the survival of the nymphs of the endangered aquatic hemipteran Kirkaldyia (=Lethocerus) deyrolli (Belostomatidae: Heteroptera) is directly and indirectly affected by the abundance of their amphibian larval prey (tadpoles). Young nymphs of K. deyrolli mainly feed on tadpoles, regardless of differences in prey availability. Nymphs provided with tadpoles grow faster than nymphs provided with invertebrate prey. Therefore, tadpole consumption seems to be required to allow the nymphs to complete their larval development. In addition, the survival of K. deyrolli nymphs was greater during the period of highest tadpole density (June) than during a period of low tadpole density (July). Higher tadpole density moderates predation pressure from the water scorpion Laccotrephes japonensis (Nepidae: Heteroptera) on K. deyrolli nymphs; i.e., it has a density-mediated indirect effect. These results suggest that an abundance of tadpoles in June provides food for K. deyrolli nymphs (a direct bottom-up effect) and moderates the predation pressure from L. japonensis (an indirect bottom-up effect). An abundance of amphibian prey is indispensable for the conservation of this endangered giant water bug species.
Using "Double Metre" method in studying Secuieu prairies (Apuseni Mountains)  [cached]
Ioan PUIA,Denes PAZMANY,I. TARNAVEANU,Attila T. SZABO
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 1978,
Abstract: Dans les recherches actuelles des prairies de la Roumanie il s'impose l'application d'une methode qui fournit des donnees numeriques concernant la structure du tapis vert, c'est-a-dire les changements quantitatifs et qualitatifs qui y ont lieu, dans le but: - de connaitre les changements structurax, consequence de l'amelioration, application d'engrais chimiques et naturals, herbicides, drainage etc; de trouver de nouveaux procedes pour apprecier la valeur des prairies au point de vue du paturage; de preciser les unites utilisees dans la typologie pratologique. En poursuivant nos etudes ecologiques concernant la productivite des prairies et le circuit de l'azote dans les praires (6,7), de meme utiliser une methode simple d'etude ecologique de la structure des prairies ayant comme but les changements intervenes dans les experiences effectuees dans le stationnaire grace a l'enregistrement de certains indices specifiques (frequnce specifique, contribution specifique).
Des broussailles dans les prairies alpines  [cached]
Olivier Camacho,Laurent Dobremez,Alain Capillon
Revue de Géographie Alpine , 2009, DOI: 10.4000/rga.566
Abstract: Landscape closing due to the decline in agricultural activity is considered to be a major problem in the Alps. Abondance Valley provides a good example of this phenomenon and is also representative of a paradox commonly found in the Northern French Alps: the mountainsides and alpine pastures are still used, whereas they are becoming increasingly afforested. Environmental conditions play a major role in the localisation of agricultural land uses, but they are not sufficient to explain why pastures still in use are being invaded by shrub. Even if cutting makes it possible to effectively control the encroachment by woody species, this is not true for uncut pastures where grazing is not able to keep up with grass production. This situation is repeated every year and is the likely cause of the colonisation by woody species. To ensure their forage system and to simplify their work, farmers tend to establish grazing units that are oversized in relation to the needs of their animals. They implement compensatory practices that consist of mechanical maintenance as a complement to grazing to limit the dynamics of woody species. These labour-intensive practices are not used on all of the pastures. The analysis of farmers’ practices by agronomists is therefore a useful complement to studies of physical and socio-economic environments, at the level of the grazed field as well as at that of the valley as a whole. La dégradation des paysages par suite du recul de l’activité agricole est considérée comme un enjeu majeur dans les Alpes. La vallée d’Abondance illustre bien ce phénomène de fermeture de l’espace mais elle est en outre représentative d’un paradoxe assez répandu dans les Alpes du nord fran aises : les versants et les alpages sont encore exploités et pourtant ils se boisent progressivement. Les conditions de milieux jouent un r le majeur sur la localisation des usages agricoles de l'espace, mais elles ne peuvent pas suffire pour expliquer pourquoi l'embroussaillement gagne des prairies encore exploitées. Si la fauche permet de lutter efficacement contre l’avancée des ligneux, il n’en est pas de même dans les prairies paturées non fauchées où la capacité de prélèvement par les troupeaux s’avère faible par rapport à la production d’herbe. Cette situation se répète d’année en année et c’est la cause la plus probable de la propagation des ligneux. Pour sécuriser leur système fourrager et pour simplifier le travail, les éleveurs constituent des unités de paturage surdimensionnées par rapport aux besoins des animaux. Ils mettent en uvre des pratiques de rattrapage,
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