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Hintergrund: Kopf-Hals-Tumore sind bei Erstdiagnose meist weit fortgeschritten. Tabak- und Alkohol-Konsum sind die bekanntesten Risikofaktoren. Eine Infektion mit Humanen-Papillomaviren (HPV), insbesondere Typ 16, spielt eine zunehmend wichtige Rolle in der Ätiologie und der Anteil der HPV-getriebenen[zum vollständigen Text gelangen Sie über die oben angegebene URL], 102. Jahrestagung der Vereinigung Südwestdeutscher Hals-Nasen-Ohrenärzte

Extreme habitats challenge animals with highly adverse conditions, like extreme temperatures or toxic substances. In this paper, we report of a fish (Poecilia mexicana) inhabiting a limestone cave in Mexico. Several springs inside the cave are rich in toxic H2S. We demonstrate that a behavioural adaptation, aquatic surface respiration (ASR), allows for the survival of P. mexicana in this extreme, sulphidic habitat. Without the possibility to perform ASR, the survival rate of P. mexicana was low even at comparatively low H2S concentrations. Furthermore, we show that food limitation affects the survival of P. mexicana pointing to energetically costly physiological adaptations to detoxify H2S

The newly sequenced mitochondrial genomes of 107 Asian swamp buffalo (Bubalus bubalis carabensis) allowed the reconstruction of the matrilineal divergence since ~900 Kya. Phylogenetic trees and Bayesian skyline plots suggest a role of the glacial periods in the demographic history of swamp buffalo. The ancestral swamp-buffalo mitogenome is dated ~232 ± 35 Kya. Two major macro-lineages diverged during the 2nd Pleistocene Glacial Period (~200–130 Kya), but most (~99%) of the current matrilines derive from only two ancestors (SA1′2 and SB) that lived around the Last Glacial Maximum (~26–19 Kya). During the late Holocene optimum (11–6 Kya) lineages differentiated further, and at least eight matrilines (SA1, SA2, SB1a, SB1b, SB2a, SB2b, SB3 and SB4) were domesticated around 7–3 Kya. Haplotype distributions support an initial domestication process in Southeast Asia, while subsequent captures of wild females probably introduced some additional rare lineages (SA3, SC, SD and SE). Dispersal of domestic buffaloes created local population bottlenecks and founder events that further differentiated haplogroup distributions. A lack of maternal gene flow between neighboring populations apparently maintained the strong phylogeography of the swamp buffalo matrilines, which is the more remarkable because of an almost complete absence of phenotypic differentiation.

True gazelles (genus Gazella) are a prime example of a mammalian group with considerable taxonomic confusion. This includes the descriptions of several dark grey taxa of questionable validity. Here, we examined captive dark grey putative Neumann’s gazelle Gazella erlangeri. Our concerted efforts to retrieve mitochondrial sequence information from old museum specimens of two dark grey gazelles, putative G. erlangeri and putative Muscat gazelle G. muscatensis, were unsuccessful. We did, however, find the mtDNA haplotypes of extant putative G. erlangeri to be nested within the haplotype variation of the Arabian gazelle G. arabica. The observed population genetic divergence between G. arabica and putative G. erlangeri (based on 11 nuclear microsatellites) was driven by genetic impoverishment of putative G. erlangeri. These results, along with morphological signatures of domestication (e.g., reduced brain case size), suggest genetic bottle necks and domestication effects as a consequence of prolonged captive breeding. Three hypotheses are discussed: (a) G. erlangeri and G. muscatensis are valid species but are now extinct; (b) one or both taxa represent phenotypic variation within G. arabica and, therefore, are synonyms of G. arabica; and (c) captive stocks, exhibiting the effects of domestication and inbreeding, are the sources for the descriptions of G. erlangeri and G. muscatensis. As concerns the conservation of gazelles, based on current knowledge, we strongly advise against using putative G. erlangeri for any introduction initiative but recommend the continued captive management of putative G. erlangeri. Click here to access supplementary files.

Invasive Prosopis juliflora dispersal on Farasan Kebir (Miharraq area, Wadi Matr) was investigated in relation to endozoochory by Farasan Gazelle (Gazella gazella farasani). A germination experiment was conducted to test defecated seed viability of competing P. juliflora and Acacia ehrenbergiana. It revealed that 0.0013 ± 0.0009 Acacia seeds per gram of faeces germinated, while the rate of germinating Prosopis seeds was higher (0.0053 ± 0.0022 seeds per gram of faeces). Dung middens with a Prosopis seedling (or a young tree nearby) were distinctly closer to the putative centre of Prosopis introduction (Al-Qisar and Miharraq villages) than middens without Prosopis, suggesting that gazelles whose home ranges (mean size, females : 2.07 km2, males : 0.71 km2) encompass the gardens edging the aforementioned villages contribute to the dispersal of this invasive species. Altogether, our results suggest that gazelles on the Farasan Islands contribute to the invasion success of Prosopis ; it still needs to be investigated though to what extent also domestic livestock - in particular goats - contribute to Prosopis dispersal. Based on our present data it is recommended to reduce the number of Prosopis trees in the protected area around Wadi Matr by mechanical elimination., La gazelle endémique (Gazella gazella farasani) favorise la dispersion de l’invasive Prosopis juliflora sur les îles Farasan, Arabie Saoudite. La dispersion d’une plante invasive Prosopis juliflora sur Farasan Kébir (région de Miharraq, Ouadi Matr) a été étudiée en relation avec l’endozoochorie par la Gazelle de Farasan (Gazella gazella farasani). Une expérience de germination a été réalisée afin de tester la viabilité des graines de P. juliflora et d’Acacia ehrenbergiana, deux espèces concurrentes. Elle a révélé que 0,0013 ± 0,0009 graines d’Acacia par gramme de matière fécale ont germé, soit moins que pour les graines de Prosopis (0,0053 ± 0,0022 graines par gramme). Les amas de fèces avec un semis de Prosopis (ou un jeune arbre à proximité) étaient nettement plus proches du centre supposé d’introduction de Prosopis (villages de Al-Qisar et Miharraq) que les amas sans Prosopis, ce qui suggère que les gazelles, dont le domaine vital (2,07 km2 pour les femelles ; 0,71 km2 pour les mâles) englobe les jardins adjacents aux villages sus-mentionnés, contribuent à la dispersion de cette espèce envahissante. Au total, nos résultats suggèrent que les gazelles des îles Farasan contribuent au succès de l’invasion de Prosopis. Il reste toutefois encore à étudier dans quelle mesure le bétail domestique, en particulier les chèvres, contribue à la dispersion de Prosopis. Sur la base des données actuelles, il est recommandé de réduire le nombre d’arbres de Prosopis par élimination mécanique dans la zone protégée autour de Ouadi Matr., Wronski Torsten,Mosfer Abdulwahed N.,Plath Martin. Endemic Farasan Gazelle (Gazella gazella farasani) enhances the dispersal of invasive Prosopis juliflora on Farasan Islands, Saudi Arabia. In: Revue d'Écologie (La Terre et La Vie), tome 67, n°3, 2012. pp. 329-337.

Life history traits within species often vary among different habitats. We measured female fecundity in mollies (Poecilia mexicana) from a H2S-rich cave and from a neighbouring surface habitat, as well as in laboratory-reared individuals of both populations raised in either light or continuous darkness. Compared to conspecifics from surface habitats, cave-dwelling P. mexicana had reduced fecundity (adjusted for size) in the field. In the laboratory, the fecundity of surface mollies was higher in light than in darkness, whereas fecundity in the cave mollies was almost unaffected by the ambient light conditions. Our results suggest a heritable component to the reduction in fecundity in female cave mollies. Moreover, the reduced plasticity in fecundity of cave mollies in response to light conditions might be an example of genetic assimilation or channelling of a life history trait in a population invading a new environment.

The cave molly, Poecilia mexicana, from the Cueva del Azufre, a sulfur cave in Tabasco, Mexico, ranks among the best-studied cave fishes worldwide, despite being known from a single population only. Here we describe a newly discovered second population of cave-dwelling P. mexicana from a nearby, but mostly non-sulfidic cave (Luna Azufre). Despite apparent similarities between the two populations (such as reduced eye diameter and reduced pigmentation), a geometric morphometric analysis revealed pronounced morphological differentiation between the two cave forms

One of the most challenging questions in regard to Arabian gazelles is the status of G. erlangeri Neumann, 1906 (Fig. 1). Gazelles currently kept in captivity at King Khalid Wildlife Research Centre in Saudi Arabia and Al Wabra Wildlife Preservation in Qatar (Fig. 2) show the described combination of diagnostic features, and thus, were considered to represent G. erlangeri, even though the exact provenance of these gazelles remains obscure. However, captive ‘G. erlangeri’ may have also originated from eastern Oman and could be therefore assigned to G. muscatensis (Fig. 3). Both taxa are considered ‘extinct in the wild’ by the IUCN Red List. Past conservation efforts have been plagued by confusion about the phylogenetic relationship among various—phenotypically discernable—populations (e.g., G. erlangeri, G. muscatensis), and even the question of species boundaries was far from being certain. This lack of knowledge had a direct impact on conservation measures, especially ex situ breeding programmes, hampering the assignment of captive stocks to potential conservation units.

Multidirectional communicative interactions in social networks can have a profound effect on mate choice behavior. Male Atlantic molly Poecilia mexicana exhibit weaker mating preferences when an audience male is presented. This could be a male strategy to reduce sperm competition risk: interacting more equally with different females may be advantageous because rivals might copy mate choice decisions. In line with this hypothesis, a previous study found males to show a strong audience effect when being observed while exercising mate choice, but not when the rival was presented only before the choice tests. Audience effects on mate choice decisions have been quantified in poeciliid fishes using association preference designs, but it remains unknown if patterns found from measuring association times translate into actual mating behavior. Thus, we created five audience treatments simulating different forms of perceived sperm competition risk and determined focal males' mating preferences by scoring pre-mating (nipping) and mating behavior (gonopodial thrusting). Nipping did not reflect the pattern that was found when association preferences were measured, while a very similar pattern was uncovered in thrusting behavior. The strongest response was observed when the audience could eavesdrop on the focal male's behavior. A reduction in the strength of focal males' preferences was also seen after the rival male had an opportunity to mate with the focal male's preferred mate. In comparison, the reduction of mating preferences in response to an audience was greater when measuring association times than actual mating behavior. While measuring direct sexual interactions between the focal male and both stimulus females not only the male's motivational state is reflected but also females' behavior such as avoidance of male sexual harassment.

Scent marking in localized defecation sites (latrines) has often been interpreted in the context of male territory defense. Still, latrines could have different functions in both sexes, especially where territorial males monopolize groups of females with stable social alliances. We assessed the spatial distribution of latrines within home ranges of wild ranging Arabian gazelles (Gazella arabica) on Farasan Island (Red Sea, Saudi Arabia).

Once common throughout the entire Sahelo-Saharan region, population sizes of Dorcas gazelles (Gazella dorcas) are nowadays decreasing dramatically. The uncertain taxonomy of this species—with a variety of described subspecies without validated status—hampers conservation efforts. In this situation, phylogenetic and phylogeographic investigations using molecular techniques are highly warranted conservation tools. Here, we investigate sequence variation of the mitochondrial cytochrome b gene and control region of 73 dorcas (G. dorcas) and Saudi gazelles (G. saudiya) throughout the entire distribution range.

The phylogeny of the Arabian gazelles is generally not well understood (e.g., Groves 1996). Morphological traits were commonly used as a basis for classification leading to frequent misclassifications. Sister group relationships within the genus are only poorly resolved and there are still lively debates about the status of certain taxa (e.g., Wronski et al., unpublished). The aim of this project is to characterize several Arabian, African and Asian gazelle species using molecular tools while including several taxonomically unclear “species”.

Male-biased predation has been described from several epigean species, and in many cases, intrinsic differences between the sexes (such as male ornaments) have been suggested as an explanation. Here we report on male-biased predation of a cave fish (Poecilia mexicana) by an aquatic insect (Belostoma sp.) in a Mexican sulfur cave. P. mexicana use aquatic surface respiration (ASR) to survive in their sulfidic, hypoxic habitat. We found that males typically exhibit more ASR activity than females, which leads to increased exposure to the sit-and-wait predator that catches fish near the water surface. Our finding is novel, because male vulnerability to predation is not directly related to male traits involved in courtship, but rather due to other sexual differences in behavior and ultimately, oxygen demands.

*Department of Behaviour , Biozentrum Grindel, University of Hambur g, Martin-Luther -King Platz 3, 20146 Hambur g, Germany , Institute of Zoology , University of Zurich,W interthur erstra§e 190, CHÐ8057 Zurich, Switzerland and aDepartment of Zoology ,University of Oklahoma, 730 Van Vleet Oval, Norman, OK 73019, U .S.A.(Received 16 January 2007, Accepted 15 May 2007 )

In many species, females prefer large males as mating partners. Male size can easily be determined visually. We examined how such mate choice evolves when individuals are deprived of sensory information previously used to determine male quality. Using a cave-dwelling population of Atlantic mollies, Poecilia mexicana, as a model, we asked whether the female mating preference for large male body size still occurs in this cave fish, or whether it is lacking due to the absence of visual communication in the cave environment. In simultaneous choice tests we compared the time females spent with a large or a small male. In the river-dwelling and cave-dwelling fish, as well as the population originating from the cave entrance, we found a significant preference for large males in light. Hence, the ancestral mating preference of surface-dwelling mollies has been maintained during the evolution of the cave form. However, only the cave population exhibited a mating preference in darkness. Determination of male body size appears to have been taken over by a non-visual sensory system, probably the lateral line.

Abstract Animals colonizing lightless subterranean habitats can no longer rely on visual signals to find mating partners. In the present study, we investigated the ability of males to recognize females in two surface and a cave dwelling population of a livebearing fish, Poecilia mexicana. In surface populations males discriminated between sexes with visual plus non-visual cues available and with visual stimuli only. In the cave form the ability to discriminate with solely visual stimuli is lacking. In all three populations, males did not recognize females in darkness (infrared observations), suggesting that sex recognition via far-field communication is lacking in surface and cave dwelling P.mexicana. Different preferences in large and small males to stay near a female or a male stimulus fish probably reflect differences concerning a trade-off between sexual and aggressive behaviour.

Sexual coercion is a common behaviour for males trying to compensate for being inferior in male competition and/or female choice. We measured the cost of male sexual harassment for females as reduced feeding time in three populations of the Atlantic molly (Poecilia mexicana). Of these populations, one originated from a typical river habitat, another from a lightless cave chamber and the third one from a small, milky creek outside the cave. We gave hungry females an opportunity to feed in the presence of either another female or a male. We found the following: (1) male sexual harassment represents a cost in the river dwelling population and both small and large males significantly reduce female feeding time; and (2) sexual harassment was not detected in the other two populations (cave and cave entrance). In the cave molly, small males are at a disadvantage in female choice, but predation by an aquatic heteropteran selects against large male body size.