31 resultados para SCENT MARKING


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Scent-marking is widespread among mammals and has been observed in many felid species. Although the behaviour is well-described, little is known about its function in wild felid populations. We investigated patterns of scent-marking and its role in intra- and intersexual communication among resident and non-resident Eurasian lynx Lynx lynx by observing interactions among wild lynx at natural marking sites by means of infrared camera traps. Marking activity of resident animals showed a peak during the mating season and was lowest during the time when females gave birth and lactated. Both sexes scent-marked, but male lynx visited marking sites much more often than females and marked relatively more often when visiting a site. Most visits to marking sites were by residents but we also observed scent-marking by non-residents. Juveniles were never observed marking. We found no evidence of lynx regularly renewing scent-marks after a certain 'expiry date' but the presence of a strange scent-mark triggered over-marking. Males responded similarly to the presence of another individual's scent-mark, irrespective of whether it was the top- or the underlying scent-mark in a mixture of scent-marks they encountered. Our results suggest that marking sites could serve as 'chemical bulletin boards', where male lynx advertise their presence and gain information on ownership relationships in a given area. Females placed their urine marks on top of the ones left by resident males, but further studies are needed to explain the functions of over-marking in females.

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A major function of angiosperm flowers is the recruitment of animal pollinators that serve to transfer pollen among conspecific plants. Distinct sets of floral characteristics, called pollination syndromes, are correlated with visitation by specific groups of pollinators. Switches among pollination syndromes have occurred in many plant families. Such switches must have involved coordinated changes in multiple traits and multiple genes. Two well-studied floral traits affecting pollinator attraction are petal color and scent production. We review current knowledge about the biosynthetic pathways for floral color and scent production and their interaction at the genetic and biochemical levels. A key question in the field concerns the genes that underlie natural variation in color and scent and how such genes affect pollinator preference, reproductive isolation, and ultimately speciation.

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Scott DeLancey’s analysis of person-sensitive TAME marking in Lhasa Tibetan – “a.k.a. conjunct-disjunct marking” or “egophoricity” – has stimulated considerable discussion and debate, particularly as previously little-known languages of the Tibeto-Burman area, as well as outside it, have come to be described, and a wider range of functional factors have been taken into account. This chapter is intended as a contribution to this discussion, by presenting the first detailed analysis of person-sensitive TAME marking in a language of the Tani subgroup of Tibeto-Burman, namely Galo. Like Tournadre (2008), I find that person-sensitive TAME marking in Galo is not a grammaticalized index of person (“agreement”) nor of cross-clause subject continuity, but is instead a semantic index of an assertor’s knowledge state. Unlike in more westerly Tibeto-Burman languages, however, different construals of agency and/or volition do not seem to be factors in the Galo system. Thus, there are both similarities and differences underlying systems of person-sensitive TAME marking in different Tibeto-Burman languages; this suggests that further research - particularly, employing a diachronic perspective when possible - will be required before we can confidently characterize person-sensitive TAME marking from a pan-Tibeto-Burman (or broader) cross-linguistic perspective.

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A split-ergative construction had developed during the late MIA period (Bubenik 1998; Peterson 1998) in which subjects of perfective transitive clauses were marked ergative by an oblique form, in contrast with the nominative form for non-ergative subjects. Later in the NIA period, most NIA languages (e.g. Urdu/Hindi) developed a postpositional clitic that was added to the oblique suffix, while others (e.g. Sindhi) continued to mark ergative subjects with a generic oblique suffix. This paper focuses on one exceptional case: the Dehwali language of Gujarat. Dehwali has an ergative marker that is a fusional suffix (i.e. layer I - Masica 1991: 231) and appears to inflect to agree in number and gender with the subject it marks. I will present two possible scenarios as to the origin of the Dehwali ergative marker: that it may be the remnant of an archaic MIA oblique form, or that it may be a more recent innovation as the result of increased contact with neighbouring varieties. Based on theories of grammaticisation, I argue that the former hypothesis is more likely. These theories show that it is not uncommon for oblique case forms (i.e. ablative; genitive) to carry agentive properties.

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Due to the decomposition of biological material, hydrogen sulphide (H(2)S) is produced. In low concentrations, the well-known smell of "rotten eggs" is associated with H(2)S. In higher concentrations, H(2)S is an odourless and colourless gas that may cause rapid loss of consciousness, neurological and respiratory depression and imminent death-"... like a stroke of lightening". Hydrogen sulphide poisoning is an un-common incident that is often associated with colleague fatalities. In this study, 4 fatal accidents with 10 deceased victims are reported and the morphological and phenomenological aspects are presented. In these cases, the morphological findings, namely, discolouration of the livores, pulmonary pathologies and sub-mucosal or sub-serosal congestion bleeding were found in nearly all cases. Also the impending threat for colleagues, first aid helpers and professional rescue teams is demonstrated. The suspicion of a fatal H(2)S intoxication should be based on a precise scene analysis with respect to the possibility of life-threatening H(2)S intoxication for the helpers, the typical scent of rotten eggs, which may be noted on the corpses and the abovementioned morphological findings. The diagnosis should be confirmed by a qualitative and, if possible, quantitative analysis of H(2)S.

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INTRODUCTION: Cadaver dogs are known as valuable forensic tools in crime scene investigations. Scientific research attempting to verify their value is largely lacking, specifically for scents associated with the early postmortem interval. The aim of our investigation was the comparative evaluation of the reliability, accuracy, and specificity of three cadaver dogs belonging to the Hamburg State Police in the detection of scents during the early postmortem interval. MATERIAL AND METHODS: Carpet squares were used as an odor transporting media after they had been contaminated with the scent of two recently deceased bodies (PMI<3h). The contamination occurred for 2 min as well as 10 min without any direct contact between the carpet and the corpse. Comparative searches by the dogs were performed over a time period of 65 days (10 min contamination) and 35 days (2 min contamination). RESULTS: The results of this study indicate that the well-trained cadaver dog is an outstanding tool for crime scene investigation displaying excellent sensitivity (75-100), specificity (91-100), and having a positive predictive value (90-100), negative predictive value (90-100) as well as accuracy (92-100).