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Crystal L. Beckmann, James G. Mitchell, David A.J. Stone, Charlie Huveneers, A controlled feeding experiment investigating the effects of a dietary switch on muscle and liver fatty acid profiles in Port Jackson sharks Heterodontus portusjacksoni, Journal of Experimental Marine Biology and Ecology, Volume 448, October 2013, Pages 10-18, ISSN 0022-0981, http://dx.doi.org/10.1016/j.jembe.2013.06.009.
Fatty acid (FA) analysis is increasingly being used as a tool to investigate the diet of sharks and rays. Quantifying the diet of sharks using FA profiles, however, requires an understanding of the effects that fluctuating diet has on the biochemical pathways in different tissues, and of the time scales of FA integration. The effects of dietary changes on the muscle and liver FA profiles were investigated in a controlled feeding experiment with Port Jackson sharks (Heterodontus portusjacksoni) fed exclusively on squid then prawns for six weeks each. Multivariate analysis indicated that shark muscle and liver FA profiles were 9.8% and 7.7% dissimilar after dietary change. This suggests that dietary FAs are preferentially utilised by muscle after dietary change and that muscle FA profiles are a stronger indicator of dietary changes occurring within three weeks of sampling than the FA profiles of the liver. This should be carefully considered when determining the type of tissue and frequency of sampling needed to undertake chondrichthyan dietary studies based on FA profile analysis. Some FA biomarkers and their metabolic processes are also identified and described, but further work is required to enable quantitative assessment of a species diet. Data presented here gives justification towards more complex experiments to investigate metabolic and FA tissue incorporation rates.

Isabelle Charrier, Nicolas Mathevon, Thierry Aubin
Bearded seal males perceive geographic variation in their trills
Behavioral Ecology and Sociobiology July 2013

Geographic variation in animal vocalisations, ranging from micro- to macro-variations, has now been widely documented. These dialects can impair communication between separated groups or populations and thus may play a role in speciation processes. Although the existence of geographical variation has been already shown in some pinnipeds species, the extent to which individuals perceive it is poorly understood. Here, we studied this question in the bearded seal Erignatus barbatus, a species found across different arctic regions. As in other phocids, bearded seal males emit sophisticated acoustic displays while defending an aquatic territory during the breeding season. First, we used playbacks to demonstrate that the trill has a function in territorial defence. Second, we used synthetic trills from two distinct populations (Nunavut and Greenland), to show that bearded seal males perceived the geographic variation in the trills. Males from Greenland responded more strongly to trills from local males than those from a distant area (Nunavut). This study provides the first experimental evidence that phocid males can perceive geographic variation in their vocalisations. Acoustic analyses combined with playback experiments can help to identify distinct populations in bearded seals. This may then provide information on both strength and scale of breeding site fidelity in this and potentially other species.

Junhua Hu, Zhigang Jiang, David P. Mallon, Metapopulation viability of a globally endangered gazelle on the Northeast Qinghai–Tibetan Plateau, Biological Conservation, Volume 166, October 2013, Pages 23-32, ISSN 0006-3207, http://dx.doi.org/10.1016/j.biocon.2013.06.011.
Conservationists are far from able to assist all species threatened by extinction. Population Viability Analysis (PVA) is often used to guide decisions about the management of threatened species. Using the updated Vortex package, we carried out a PVA for Przewalski’s gazelle Procapra przewalskii, a globally endangered gazelle and conservation focus on the Qinghai–Tibetan Plateau, based on the extensive field surveys between 1994 and 2008 on the nine existing subpopulations (i.e., Yuanzhe, Hudong, Ketu, Shadao, Ganzihe, Haergai, Bird Island, Tianjun and Gonghe). Population size varied largely across subpopulations during the simulation. The nine subpopulations faced two distinct fates within the next 200 years: two will likely survive while the other seven appeared likely to go extinct. The average probability of extinction (PE) of subpopulations was 97.1%, with the mean time to extinction 66.7 years. The metapopulation will most likely decrease in size, but could persist. The number of offspring per adult female per year (OFY), the sex ratio, and the mortality of young females will seemingly play important roles in determining persistence, as will carrying capacity and inbreeding depression to be a lesser degree. The projected size and extinction rates for the subpopulations responded differently to variation in population parameters, with the highest sensitivity in Haergai. OFY was the most important demographic parameter for explaining variation in population size. These findings advance our understanding of how to mitigate extinction risks for the endangered Przewalski’s gazelle and provide useful insights for its conservation that may also be applicable to other large ungulates.

GUTIéRREZ, J., PIANTONI, C., IBARGüENGOYTíA, N.. Altitudinal effects on life history parameters in populations of Liolaemus pictus argentinus (Sauria: Liolaemidae). Acta Herpetologica, North America, 8, mar. 2013. Available at: <http://www.fupress.net/index.php/ah/article/view/11056>.
We used skeletochronology to assess the age structure, body size and sexual maturity in two populations of Liolaemus pictus argentinus from San Carlos de Bariloche, Argentina. The species occupies a wide altitudinal range within the Patagonian Lake District which enabled us to choose populations from two climatic extremes: 771 m a.s.l. and 1615-1769 m a.s.l. Age of sexual maturity in both populations of L. p. argentinus is achieved with a minimum body size of 49 mm. However, at the high-altitude site, lizards matured between the ages of three to six years and had a lifespan of eight years limiting some individual’s reproductive life to only two years. Lizards from the low-altitude site achieved maturity at the age of four and lived until the age of nine years old. Despite the environmental variations between sites populations’ growth curves’ patterns were similar represented by a rapid initial growth rate of 10.3 mm/year in youngest juvenile which slowed considerably to 4.9 mm/year after attaining sexual maturity, as energy is reallocated towards reproduction, to finally grow at a rate of 0.1 mm/year in the oldest adults. Present results show intraspecific differences in L. pictus, whether it results from adaptive polymorphism or physiological plasticity remains uncertain.

KLEEWEIN, A., WöSS, G.. Status of the European pond turtle, Emys orbicularis>/em> (Reptilia: Testudines: Emydidae) in Vorarlberg, Austria. Acta Herpetologica, North America, 8, jul. 2013. Available at: <http://www.fupress.net/index.php/ah/article/view/12502>.
Prehistoric and historic records of Emys orbicularis (Linnaeus, 1758) for the western Austrian province of Vorarlberg and adjacent regions are reviewed. Two recently captured pond turtles allowed the first analyses of mitochondrial cytochrome b haplotypes for the province. Both turtles represent lineage IV haplotypes, whereas lineage II is expected to be native. We conclude that native E. orbicularis are extinct in Vorarlberg.

GVOžDíK, V., JAVůRKOVá, V., KOPECKý, O.. First evidence of a paedomorphic population of the smooth newt (Lissotriton vulgaris) in the Czech Republic. Acta Herpetologica, North America, 8, jun. 2013. Available at: <http://www.fupress.net/index.php/ah/article/view/11865>.
Facultative paedomorphosis is an environmentally induced polymorphism that is well known for many caudate species including newts. Although facultative paedomorphosis has been documented in some smooth-newt populations, records of entirely paedomorphic populations outside the Balkans are limited. Here we present the first evidence of a paedomorphic population of the smooth newt in the Czech Republic with discussion of potential causes that need to be further tested.

Blanco, R. E., Jones, W. W. and Milne, N. (2013), Is the extant southern short-tailed opossum a pigmy sabretooth predator?. Journal of Zoology. doi: 10.1111/jzo.12050
Hypertrophied canines evolved several times among mammalian carnivores. Several palaeobiological hypotheses related to sabretooth evolution and killing behaviours have been suggested based on biomechanical and functional considerations. However, the lack of well-studied extant analogues makes it difficult to test these hypotheses. Here we propose the South American short-tailed opossum Monodelphis dimidiata as a living analogue of extinct sabretooth predators. Our morphological analysis shows that M. dimidiata not only has relatively the largest canines among extant marsupial carnivores, but they are also within the range of those of sabretooth predators. It also has cranial adaptations for a wide gape typical of sabretooth carnivores. The small body size of this species allows further biological studies that can provide useful information to understand the evolution, behaviour and physiology of extinct sabretooth carnivores.

Yukio Matsumoto, Takeshi Takegaki, Female mate choice copying increases egg survival rate but does not reduce mate-sampling cost in the barred-chin blenny, Animal Behaviour, Available online 5 July 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.05.024.
Female mate choice copying is assumed to increase the opportunity for sexual selection; however, this phenomenon has only been evaluated for a few species in the wild. This study confirmed the presence of female mate choice copying in a wild population of the paternal brooding blenny Rhabdoblennius nitidus, with the behaviour of the first copying females being repeatedly copied by subsequent females. Usually, parental phase males have lower mating success than courtship phase males; however, we manipulated parental phase males to mate with a demonstrator female, causing these males to be repeatedly chosen by other females. We then tested the benefit of mate choice copying in the wild. Our observations of female mate sampling do not support the hypothesis that mate choice copying causes a decline in the number of nests visited by females, time spent mate sampling and male harassment. All copying females mated with males tending the eggs of other females, whereas the majority of other females mated with males not tending eggs. Thus, it is highly possible that copying behaviour reduced the risk of egg desertion by males, which occurs when small numbers of eggs are tended.

Mayer J, Tsangaras K, Heeger F, Avila-Arcos M, Stenglein MD, Chen W, Sun W, Mazzoni CJ, Osterrieder N, Greenwood AD (2013): A novel endogenous betaretrovirus group characterized from polar bears (Ursus maritimus) and giant pandas (Ailuropoda melanoleuca). Virology 443, 1-10. doi: 10.1016/j.virol.2013.05.008.
Transcriptome analysis of polar bears (Ursus maritimus) yielded sequences with highest similarity to the human endogenous retrovirus group HERV-K(HML-2). Further analysis of the polar bear draft genome identified an endogenous betaretrovirus group comprising 26 proviral copies and 231 solo LTRs. Molecular dating indicates the group originated before the divergence of bears from a common ancestor but is not present in all carnivores. Closely related sequences were identified in the giant panda (Ailuropoda melanoleuca) and characterized from its genome. We have designated the polar bear and giant panda sequences U. maritimus endogenous retrovirus (UmaERV) and A. melanoleuca endogenous retrovirus (AmeERV), respectively. Phylogenetic analysis demonstrated that the bear virus group is nested within the HERV-K supergroup among bovine and bat endogenous retroviruses suggesting a complex evolutionary history within the HERV-K group. All individual remnants of proviral sequences contain numerous frameshifts and stop codons and thus, the virus is likely non-infectious.

Christopher Young, Sabine Hähndel, Bonaventura Majolo, Oliver Schülke, Julia Ostner
Male coalitions and female behaviour affect male mating success independent of dominance rank and female receptive synchrony in wild Barbary macaques
Behavioral Ecology and Sociobiology July 2013

Dominant mammalian males should gain a reproductive advantage due to their greater fighting abilities. However, the extent to which they can monopolise access to females varies across species. In primates and recently other mammalian species, the Priority of Access (PoA) model is commonly used to measure the degree to which male rank and female receptive synchrony affect mating skew. Few studies have examined the factors which lead to deviations from the expectations of the model. Here, we investigate male mating skew in wild Barbary macaques (Macaca sylvanus). We examined four of the main factors which affect male mating success: the roles of male rank, female receptive synchrony, coalitionary activity and female behaviour. We found that male mating was skewed up the hierarchy, but there was a large deviation from the PoA model’s expectations with high-ranked males not gaining as big a share as expected. Females frequently initiated sexual encounters, predominantly with mid-ranked males, increasing their mating success. Male coalitionary activity independently increased mating success. Frequent associations with females were costly to males as they were the targets of bridging coalitions, decreasing future mating opportunities for the targets. High-ranking males did not increase their mating success directly through bridging coalitions but acted to dilute the effects of female behaviour. By examining different factors affecting mating skew, we are able to show that alternative male and female mating strategies are effective in reducing the monopolisation potential of the dominant male.

Crocodylians evolved scattered multi-sensory micro-organs
Di-Poï N, Milinkovitch MC
EvoDevo 2013, 4:19 (2 July 2013)

During their evolution towards a complete life cycle on land, stem reptiles developed both an impermeable multi-layered keratinized epidermis and skin appendages (scales) providing mechanical, thermal, and chemical protection. Previous studies have demonstrated that, despite the presence of a particularly armored skin, crocodylians have exquisite mechanosensory abilities thanks to the presence of small integumentary sensory organs (ISOs) distributed on postcranial and/or cranial scales.
Here, we analyze and compare the structure, innervation, embryonic morphogenesis and sensory functions of postcranial, cranial, and lingual sensory organs of the Nile crocodile (Crocodylus niloticus) and the spectacled caiman (Caiman crocodilus). Our molecular analyses indicate that sensory neurons of crocodylian ISOs express a large repertoire of transduction channels involved in mechano-, thermo-, and chemosensory functions, and our electrophysiological analyses confirm that each ISO exhibits a combined sensitivity to mechanical, thermal and pH stimuli (but not hyper-osmotic salinity), making them remarkable multi-sensorial micro-organs with no equivalent in the sensory systems of other vertebrate lineages. We also show that ISOs all exhibit similar morphologies and modes of development, despite forming at different stages of scale morphogenesis across the body.
The ancestral vertebrate diffused sensory system of the skin was transformed in the crocodylian lineages into an array of scattered discrete multi-sensory micro-organs innervated by multiple pools of sensory neurons. This discretization of skin sensory expression sites is unique among vertebrates and allowed crocodylians to develop a highly-armored, but very sensitive, skin.

Francesca Boggiano, Claudio Ciofi, Luigi Boitani, Angela Formia, Lorenza Grottoli, Chiara Natali, Paolo Ciucci, Detection of an East European wolf haplotype puzzles mitochondrial DNA monomorphism of the Italian wolf population, Mammalian Biology – Zeitschrift für Säugetierkunde, Available online 4 July 2013, ISSN 1616-5047, http://dx.doi.org/10.1016/j.mambio.2013.06.001.
Southern European wolves suffered from reiterated population declines during glacial periods and historically due to human persecution. Differently from other European wolf populations, a single mitochondrial DNA (mtDNA) control region haplotype (W14) has been so far described in the Italian wolves, although no intensive genetic sampling has ever been conducted in historical source populations from central and southern Italy. Using non-invasive genetic techniques, we report the occurrence of an unexpected mtDNA haplotype (W16) in the wolf population of the Abruzzo, Lazio and Molise National Park (PNALM), central Italy. This haplotype, detected in three out of 90 faecal samples from the PNALM, was previously reported in wolves from the North Carpathians, Slovakia and the Balkans only. Microsatellite analysis and molecular sex determination confirmed that the W16 samples belonged to three distinct wolves. Although alternative explanations can be formulated for the origin of this mtDNA haplotype in the otherwise monomorphic Italian wolf population, assignment procedures indicated the likely admixed ancestry of one W16 sample with East European wolves. Anthropogenic introgression with dogs has been detected in the Italian wolf population using nuclear DNA microsatellites, but no population-wide genetic survey had previously reported a mtDNA control region variant in Italian wolves. Our findings strongly suggest that, in addition to wolf × dog hybridization, captive-released wolves or wolf × dog hybrids may successfully interbreed with wolves in the wild, and that human-mediated introgression may occur even in well established protected areas.

Zootaxa 3683 (5): 581–588 (8 Jul. 2013)
Schistura paucireticulata, a new loach from Tuirial River, Mizoram, India (Teleostei: Nemacheilidae)

Schistura paucireticulata, new species, is described from the Tuirial River in Mizoram, India. It is distinguished from its congeners by a combination of characters: 8–9 brown bars on the body, bars in front of the dorsal fin divided into 2-3 small bars forming a reticulations; basicaudal bar black, dissociated; dorsal fin spotted, with 4 simple and 8½ branched rays; anal fin with 3 simple and 6 branched rays; lateral line complete; caudal fin deeply emarginated with 9+8 branched rays; well developed axillary pelvic lobe; and caudal fin with numerous black spots arranged in 3–4 bars.

Sternberg, D. and Kennard, M. J. (2013), Phylogenetic effects on functional traits and life history strategies of Australian freshwater fish. Ecography. doi: 10.1111/j.1600-0587.2013.00362.x
Understanding the biogeographic and phylogenetic basis to interspecific differences in species’ functional traits is a central goal of evolutionary biology and community ecology. We quantify the extent of phylogenetic influence on functional traits and life-history strategies of Australian freshwater fish to highlight intercontinental differences as a result of Australia’s unique biogeographic and evolutionary history. We assembled data on life history, morphological and ecological traits from published sources for 194 Australian freshwater species. Interspecific variation among species could be described by a specialist–generalist gradient of variation in life-history strategies associated with spawning frequency, fecundity and spawning migration. In general, Australian fish showed an affinity for life-history strategies that maximise fitness in hydrologically unpredictable environments. We also observed differences in trait lability between and within life history, morphological and ecological traits where in general morphological and ecological traits were more labile. Our results showed that life-history strategies are relatively evolutionarily labile and species have potentially evolved or colonised in freshwaters frequently and independently allowing them to maximise population performance in a range of environments. In addition, reproductive guild membership showed strong phylogenetic constraint indicating that evolutionary history is an important component influencing the range and distribution of reproductive strategies in extant species assemblages. For Australian freshwater fish, biogeographic and phylogenetic history contribute to broad taxonomic differences in species functional traits, while finer scale ecological processes contribute to interspecific differences in smaller taxonomic units. These results suggest that the lability or phylogenetic relatedness of different functional traits affects their suitability for testing hypothesis surrounding community level responses to environmental change.

Baldwin, C. C. (2013), The phylogenetic significance of colour patterns in marine teleost larvae. Zoological Journal of the Linnean Society, 168: 496–563. doi: 10.1111/zoj.12033
Ichthyologists, natural-history artists, and tropical-fish aquarists have described, illustrated, or photographed colour patterns in adult marine fishes for centuries, but colour patterns in marine fish larvae have largely been neglected. Yet the pelagic larval stages of many marine fishes exhibit subtle to striking, ephemeral patterns of chromatophores that warrant investigation into their potential taxonomic and phylogenetic significance. Colour patterns in larvae of over 200 species of marine teleosts, primarily from the western Caribbean, were examined from digital colour photographs, and their potential utility in elucidating evolutionary relationships at various taxonomic levels was assessed. Larvae of relatively few basal marine teleosts exhibit erythrophores, xanthophores, or iridophores (i.e. nonmelanistic chromatophores), but one or more of those types of chromatophores are visible in larvae of many basal marine neoteleosts and nearly all marine percomorphs. Whether or not the presence of nonmelanistic chromatophores in pelagic marine larvae diagnoses any major teleost taxonomic group cannot be determined based on the preliminary survey conducted, but there is a trend toward increased colour from elopomorphs to percomorphs. Within percomorphs, patterns of nonmelanistic chromatophores may help resolve or contribute evidence to existing hypotheses of relationships at multiple levels of classification. Mugilid and some beloniform larvae share a unique ontogenetic transformation of colour pattern that lends support to the hypothesis of a close relationship between them. Larvae of some tetraodontiforms and lophiiforms are strikingly similar in having the trunk enclosed in an inflated sac covered with xanthophores, a character that may help resolve the relationships of these enigmatic taxa. Colour patterns in percomorph larvae also appear to diagnose certain groups at the interfamilial, familial, intergeneric, and generic levels. Slight differences in generic colour patterns, including whether the pattern comprises xanthophores or erythrophores, often distinguish species. The homology, ontogeny, and possible functional significance of colour patterns in larvae are discussed. Considerably more investigation of larval colour patterns in marine teleosts is needed to assess fully their value in phylogenetic reconstruction.

de Santana, C. D. and Vari, R. P. (2013), Brown ghost electric fishes of the Apteronotus leptorhynchus species-group (Ostariophysi, Gymnotiformes); monophyly, major clades, and revision. Zoological Journal of the Linnean Society, 168: 564–596. doi: 10.1111/zoj.12022
Neotropical brown ghost electric knifefishes of the Apteronotus leptorhynchus species-group are reviewed. A series of synapomorphies delimit the species-group and the two major subunits that comprise that clade. The phylogeny is concordant with the hypothesis of a primary division within the clade resultant from Andean uplift events 8 Mya and with the existence of ancestral components of the species-group 12 Mya. Species of the species-group are characterized by morphological stasis across that time frame. Apteronotus leptorhynchus, previously considered to be a widely distributed and morphologically variable species, was found to encompass five species. The description of the four new species is supplemented by the redescription of the five previously recognized forms within the species-group. Members of this clade are broadly distributed through the Essequibo River and Río Orinoco of the Atlantic slope of South America, the Ríos Aroa, Atrato, Cauca, Magdalena, and Yaracuy, and the rivers of the Lago Maracaibo basin of the Caribbean slope and drainages in northern Colombia and Panama along the Pacific versant.

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