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Parkville, Australia

Schut E.,University of Groningen | Aguilar J.R.-D.,CSIC - National Museum of Natural Sciences | Merino S.,CSIC - National Museum of Natural Sciences | Magrath M.J.L.,Zoos Victoria | And 2 more authors.
Immunogenetics | Year: 2011

The major histcompatibility complex (MHC) is a vital component of the adaptive immune system in all vertebrates. This study is the first to characterize MHC class I (MHC-I) in blue tits (Cyanistes caeruleus), and we use MHC-I exon 3 sequence data from individuals originating from three locations across Europe: Spain, the Netherlands to Sweden. Our phylogeny of the 17 blue tit MHC-I alleles contains one allele cluster with low nucleotide diversity compared to the remaining more diverse alleles. We found a significant evidence for balancing selection in the peptide-binding region in the diverse allele group only. No separation according to geographic location was found in the phylogeny of alleles. Although the number of MHC-I loci of the blue tit is comparable to that of other passerine species, the nucleotide diversity of MHC-I appears to be much lower than that of other passerine species, including the closely related great tit (Parus major) and the severely inbred Seychelles warbler (Acrocephalus sechellensis). We believe that this initial MHC-I characterization in blue tits provides an important step towards understanding the mechanisms shaping MHC-I diversity in natural populations. © 2011 The Author(s). Source

Gillespie G.R.,55 Union Street | Kum K.C.,Zoos Victoria
Victorian Naturalist | Year: 2011

The Bleating Tree Frog Litoria dentata is a pond-breeding species distributed along the east coast of Australia from southern Queensland to southern New South Wales. We report the discovery of a population of this species in Victoria, near Genoa, East Gippsland. This finding constitutes a southerly range extension for the species and takes to 38 the number of frog species known to occur in Victoria. Source

Knowledge of life history and population demography of threatened amphibians is poor. I used skeletochronology in conjunction with mark-recapture data to examine growth rates, age at maturity, and longevity of the spotted tree frog, Litoria spenceri, a critically endangered Australian species. Ages were reliably determined for 578 individuals across two populations at 335- and 1110-m elevation. Females attained larger body sizes than males and took longer to reach sexual maturity, consistent with most anurans. Males matured at 2 yr and females at 3-4 yr at lower elevations, whereas at higher elevations, males matured at 3-4 yr and females took up to 6 yr to mature, which is slow compared with most anurans. Overall, L. spenceri is long-lived, with a maximum confirmed age of 14 yr. These life history attributes have implications for population dynamics of L. spenceri, which may have markedly different demographic responses to certain threatening processes compared with faster growing, shorter lived species. This study highlights the value and need for more life history and demographic data on threatened species. Generalizations about population demography and dynamics across environmental gradients should be made cautiously. © 2011 The Herpetologists' League, Inc. Source

Leadbeater's possum (Gymnobelideus leadbeateri) is a cryptic, endangered species that is notoriously difficult to detect using conventional mammal survey methods. However, the imitation of the species' social contact and/or alarm calls has previously been found to attract resident animals. Call imitation was employed as a secondary survey method to confirm ongoing site occupancy by Leadbeater's possum at Yellingbo Nature Conservation Reserve. All call imitation reported here was conducted at sites currently or previously known to be occupied by particular family groups. The results indicate that the method has considerable promise as a tool to facilitate broad-scale surveys targeting this species. However, 'false negatives' did occur during the surveys at Yellingbo, highlighting that additional testing is required to adequately characterise the species' response patterns, in particular variation in the response rate in occupied territories and the distance over which animals will respond. A detailed understanding of these factors is essential to permit reliable interpretation of survey findings. Source

Symonds M.R.E.,University of Melbourne | Symonds M.R.E.,Deakin University | Magrath M.J.L.,Zoos Victoria | Latty T.M.,University of Calgary | Latty T.M.,University of Sydney
Journal of Insect Behavior | Year: 2012

For group-living animals the choice of whether to join aggregations or initiate their own is influenced by potential benefits such as group protection and reduced energetic expenditure, as well as costs such as competition for food and mates. The bark beetle Ips grandicollis is an invasive pest species that colonises recently felled timber in Australian pine (Pinus spp.) plantations. Male beetles initiate colonies by burrowing under the bark of trees and emitting an aggregation pheromone which attracts conspecifics, including a harem of females with whom they mate. We predicted that males that initiated colonies, or who arrived early, would have larger harems than later arrivals (due to decreased competition for females). However, we found the opposite effect with early-arriving males actually associated with fewer females than later arriving males, although this may have resulted from some females leaving harems as they get older. We conclude that pioneering does not improve male likelihood of attracting females in Ips grandicollis, at least initially, but it may provide advantages for offspring when competing for food during development. © 2011 Springer Science+Business Media, LLC. Source

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