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Tiger Snakes (tiger + snake)
Selected AbstractsKeratin-lipid structural organization in the corneous layer of snake,BIOPOLYMERS, Issue 12 2009Alberto Ripamonti Abstract The shed epidermis (molt) of snakes comprises four distinct layers. The upper two layers, here considered as ,-layer, contain essentially ,-keratin. The following layer, known as mesos-layer, is similar to the human stratum corneum, and is formed by thin cells surrounded by intercellular lipids. The latter layer mainly contains ,-keratin. In this study, the molecular assemblies of proteins and lipids contained in these layers have been analyzed in the scale of two species of snakes, the elapid Tiger snake (TS, Notechis scutatus) and the viperid Gabon viper (GV, Bitis gabonica). Scanning X-ray micro-diffraction, FTIR and Raman spectroscopies, thermal analysis, and scanning electron microscopy experiments confirm the presence of the three layers in the GV skin scale. Conversely, in the TS molt a typical ,-keratin layer appears to be absent. In the latter, experimental data suggest the presence of two domains similar to those found in the lipid intercellular matrix of stratum corneum. X-ray diffraction data also allow to determine the relative orientation of keratins and lipids. The keratin fibrils are randomly oriented inside the layers parallel to the surface of scales while the lipids are organized in lamellar structures having aliphatic chains normal to the scale surface. The high ordered lipid organization in the mature mesos layer probably increases its effectiveness in limiting water-loss. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 1172,1181, 2009. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] Do ,Quiet' Places Make Animals Placid?ETHOLOGY, Issue 6 2005Island vs. Most animals that possess potent venom display a wide variety of warning messages to discourage predators. Tiger snakes are large and highly venomous elapids that exhibit these anti-predator behaviours. We compared the anti-predator behaviours of two neighbouring and genetically indistinguishable populations in Western Australia (Herdsman Lake, HL and Carnac Island, CI). CI is free from human, native and feral predation. All of these factors represent a continual threat on HL situated on the mainland. Neither body size, nor sex influenced defensive behaviours. However, we observed a marked inter-population difference among adults in the degree to which anti-predator behaviours were displayed when snakes were continually aggravated: HL snakes exhibited a typical warning signal (flat-neck) and bite, while CI snakes remained very docile. In stark contrast, neonates of both populations exhibited marked anti-predator behaviours and both populations were indistinguishable in terms of the intensity of display. Neonates reared in captivity, hence regularly confronted by human predators, became more defensive in comparison with neonates exposed to natural conditions on CI; similarly several adult CI snakes kept in captivity became more defensive. Our results highlight the extreme behavioural plasticity of snakes. We also hypothesize that CI snakes may become more placid over time as they grow up in an environment free from predation. [source] Isolation and characterization of novel microsatellite markers from the Australian tiger snakes (Elapidae: Notechis) and amplification in the closely related genus HoplocephalusMOLECULAR ECOLOGY RESOURCES, Issue 3 2001Ian A. W. Scott Abstract We provide details of seven microsatellite loci (out of 20 primer pairs designed) that exhibited the cleanest and strongest banding patterns for the Eastern tiger snake Notechis scutatus. These loci were used to screen 76 individuals from across the geographical range of N. scutatus and a further 14 individuals of the closely related and endangered broadheaded snake Hoplocephalus bungaroides. We observed large numbers of alleles per locus (14,52) and relatively high levels of heterozygosity (0.270,0.696) within the N. scutatus sample. These markers are also likely to be informative for work on H. bungaroides. [source] Causes and consequences of aggregation by neonatal tiger snakes (Notechis scutatus, Elapidae)AUSTRAL ECOLOGY, Issue 2 2009FABIEN AUBRET Abstract Although snakes traditionally have been regarded as asocial animals, recent studies have revealed complex interactions among neonatal snakes and their mothers. We noticed frequent aggregation by captive neonatal Australian elapids (tiger snakes, Notechis scutatus), and conducted simple experiments to clarify the proximate causation of, and potential consequences of, aggregative behaviour. Litters of neonates exhibited statistically significant aggregation (clustering) in empty containers, especially if the test area was subjected to rapid cooling. Aggregation was most pronounced inside shelter-sites, and familiar shelters (i.e. containing scent cues from the litter) attracted snakes more than did novel (unscented) shelters. Snakes in larger aggregations cooled more slowly (reflecting their higher combined mass and thus, thermal inertia) and higher body temperatures facilitated neonatal locomotor performance, retreat-site location and anti-predator tactics. Plausibly, aggregation in neonatal tiger snakes (and other reptiles) functions to retard cooling rates, with the result that the young snakes are better able to evade or repel attacks by predators. [source] | ||||||||||