Abstract View

Zootaxa 3626 (4): 401–428 (15 Mar. 2013)
External morphology and osteology of Darevskia rudis (Bedriaga, 1886), with a taxonomic revision of the Pontic and Small-Caucasus populations (Squamata: Lacertidae)

A broad sample of Darevskia rudis from the main part of its range was reviewed with regard to external morphology (discriminant, UPGMA, MST and ANOVA analyses) and osteology. Darevskia bithynica is raised to species rank, with two subspecies: D. b. bithynica and D. b. tristis. The other subspecies are fairly similar (D. r. rudis being the most different).
Two singular populations are described as subspecies: D. r. mirabilis ssp. nov. from Kaçkar Mountains, geographically adjoins the otherwise different D. r. bischoffi and D. r. bolkardaghica ssp. nov., which is geographically isolated but that seems to be very closely related to D. r. obscura.

Zootaxa 3626 (4): 531–542 (15 Mar. 2013)
A taxonomic review of the Golden-green Woodpecker, Piculus chrysochloros (Aves: Picidae) reveals the existence of six valid taxa

Piculus chrysochloros (Vieillot 1818) is a species of woodpecker that ranges from Argentina to Panama, occurring in lowland forests as well as Cerrado, Caatinga and Chaco vegetation. Currently, nine subspecies are accepted, but no study has evaluated individual variation within populations, so the status of these taxa remains uncertain. Here we review the taxonomy and distribution of this species, based on morphological and morphometric data from 267 specimens deposited in ornithological collections. Our results suggest the existence of six unambiguous taxonomic units that can be treated as phylogenetic species: Piculus xanthochloros (Sclater & Salvin 1875), from northwestern South America; Piculus capistratus (Malherbe 1862), from northern Amazonia west to the Branco River; Piculus laemostictus Todd 1937, from southern Amazonia; Piculus chrysochloros (Vieillot 1818), from the Cerrado, Caatinga and Chaco; Piculus paraensis (Snethlage 1907) from the Belém Center of Endemism; and Piculus polyzonus (Valenciennes 1826) from the Atlantic Forest. Both Brazilian endemics (P. polyzonus and P. paraensis) are threatened due to habitat loss. In addition, we found one undescribed form from the Tapajós-Tocantins interfluve, now under study, that may prove to be a valid species once more specimens and other data become available.

Cajus G. Diedrich, “Extinctions of Late Ice Age Cave Bears as a Result of Climate/Habitat Change and Large Carnivore Lion/Hyena/Wolf Predation Stress in Europe,” ISRN Zoology, vol. 2013, Article ID 138319, 25 pages, 2013. doi:10.1155/2013/138319
Predation onto cave bears (especially cubs) took place mainly by lion Panthera leo spelaea (Goldfuss), as nocturnal hunters deep in the dark caves in hibernation areas. Several cave bear vertebral columns in Sophie’s Cave have large carnivore bite damages. Different cave bear bones are chewed or punctured. Those lets reconstruct carcass decomposition and feeding technique caused only/mainly by Ice Age spotted hyenas Crocuta crocuta spelaea, which are the only of all three predators that crushed finally the long bones. Both large top predators left large tooth puncture marks on the inner side of cave bear vertebral columns, presumably a result of feeding first on their intestines/inner organs. Cave bear hibernation areas, also demonstrated in the Sophie’s Cave, were far from the cave entrances, carefully chosen for protection against the large predators. The predation stress must have increased on the last and larger cave bear populations of U. ingressus (extinct around 25.500 BP) in the mountains as result of disappearing other seasonally in valleys migrating mammoth steppe fauna due to climate change and maximum glacier extensions around 22.000 BP.

Qihai Zhou, Zheng Tang, Youbang Li, Chengming Huang, Food diversity and choice of white-headed langur in fragmented limestone hill habitat in Guangxi, China, Acta Ecologica Sinica, Volume 33, Issue 2, April 2013, Pages 109-113, ISSN 1872-2032, 10.1016/j.chnaes.2013.01.007.
We studied the diet and food choice of three groups of white-headed langurs (Trachypithecus leucocephalus) from July 2002 to June 2003 at Fusui Rare Animal Reserve, Guangxi, China. Data were collected from via focus group sampling, with continuous recording. A total of 109 plant species (including 19 unidentified species) were used as food by the white-headed langur. They spent 91.6% of total feeding time feeding on leaves, 4.2% on fruits and 3.3% on stems. Flowers and other food items accounted for only 0.3% and 0.6% of total feeding time, respectively. There were significant seasonal variations in the langurs’ diets with changes in the total number of species and the diversity of food species consumed. The langurs used significantly more plant species as food in the rainy season than in the dry season (36 species vs. 26.5 species). Dietary diversity was also significantly higher in the rainy season than in the dry season (2.6 vs. 2.4). No significant seasonal variation was found in the percentage of various plant parts in their monthly diets. Though the white-headed langur fed on many plant species, 11 species made up 84.9% of their diet. There were no significant correlations between the percentage of feeding time for main food plant species and their corresponding abundance in the habitat, content of water, crude protein, crude fiber and the ratio of crude protein to crude fiber. These results suggest that food choice of the white-headed langur is not influenced by their abundance and nutritional content.

Nyffeler M, Knörnschild M (2013) Bat Predation by Spiders. PLoS ONE 8(3): e58120. doi:10.1371/journal.pone.0058120
In this paper more than 50 incidences of bats being captured by spiders are reviewed. Bat-catching spiders have been reported from virtually every continent with the exception of Antarctica (~90% of the incidences occurring in the warmer areas of the globe between latitude 30° N and 30° S). Most reports refer to the Neotropics (42% of observed incidences), Asia (28.8%), and Australia-Papua New Guinea (13.5%). Bat-catching spiders belong to the mygalomorph family Theraphosidae and the araneomorph families Nephilidae, Araneidae, and Sparassidae. In addition to this, an attack attempt by a large araneomorph hunting spider of the family Pisauridae on an immature bat was witnessed. Eighty-eight percent of the reported incidences of bat catches were attributable to web-building spiders and 12% to hunting spiders. Large tropical orb-weavers of the genera Nephila and Eriophora in particular have been observed catching bats in their huge, strong orb-webs (of up to 1.5 m diameter). The majority of identifiable captured bats were small aerial insectivorous bats, belonging to the families Vespertilionidae (64%) and Emballonuridae (22%) and usually being among the most common bat species in their respective geographic area. While in some instances bats entangled in spider webs may have died of exhaustion, starvation, dehydration, and/or hyperthermia (i.e., non-predation death), there were numerous other instances where spiders were seen actively attacking, killing, and eating the captured bats (i.e., predation). This evidence suggests that spider predation on flying vertebrates is more widespread than previously assumed.

Cahill JA, Green RE, Fulton TL, Stiller M, Jay F, et al. (2013) Genomic Evidence for Island Population Conversion Resolves Conflicting Theories of Polar Bear Evolution. PLoS Genet 9(3): e1003345. doi:10.1371/journal.pgen.1003345
Despite extensive genetic analysis, the evolutionary relationship between polar bears (Ursus maritimus) and brown bears (U. arctos) remains unclear. The two most recent comprehensive reports indicate a recent divergence with little subsequent admixture or a much more ancient divergence followed by extensive admixture. At the center of this controversy are the Alaskan ABC Islands brown bears that show evidence of shared ancestry with polar bears. We present an analysis of genome-wide sequence data for seven polar bears, one ABC Islands brown bear, one mainland Alaskan brown bear, and a black bear (U. americanus), plus recently published datasets from other bears. Surprisingly, we find clear evidence for gene flow from polar bears into ABC Islands brown bears but no evidence of gene flow from brown bears into polar bears. Importantly, while polar bears contributed <1% of the autosomal genome of the ABC Islands brown bear, they contributed 6.5% of the X chromosome. The magnitude of sex-biased polar bear ancestry and the clear direction of gene flow suggest a model wherein the enigmatic ABC Island brown bears are the descendants of a polar bear population that was gradually converted into brown bears via male-dominated brown bear admixture. We present a model that reconciles heretofore conflicting genetic observations. We posit that the enigmatic ABC Islands brown bears derive from a population of polar bears likely stranded by the receding ice at the end of the last glacial period. Since then, male brown bear migration onto the island has gradually converted these bears into an admixed population whose phenotype and genotype are principally brown bear, except at mtDNA and X-linked loci. This process of genome erosion and conversion may be a common outcome when climate change or other forces cause a population to become isolated and then overrun by species with which it can hybridize.

Venegas P, Torres-Carvajal O, Duran V, de Queiroz K (2013) Two sympatric new species of woodlizards (Hoplocercinae, Enyalioides) from Cordillera Azul National Park in northeastern Peru. ZooKeys 277: 69-90. doi: 10.3897/zookeys.277.3594
We report the discovery of two sympatric new species of Enyalioides from a montane rainforest of the Río Huallaga basin in northeastern Peru. Among other characters, the first new species is distinguishable from other Enyalioides by the combination of the following characters: strongly keeled ventral scales, more than 37 longitudinal rows of dorsals in a transverse line between the dorsolateral crests at midbody, low vertebral crest on the neck with vertebrals on neck similar in size to those between hind limbs, projecting scales on body or limbs absent, 96 mm maximum SVL in both sexes, and caudals increasing in size posteriorly within each autotomic segment. The second new species differs from other species of Enyalioides in having strongly keeled ventral scales, scales posterior to the superciliaries forming a longitudinal row of strongly projecting scales across the lateral edge of the skull roof in adults of both sexes, 31 or fewer longitudinal rows of strongly keeled dorsals in a transverse line between the dorsolateral crests at midbody, vertebrals on neck more than five times the size of vertebrals between hind limbs in adult males, projecting scales on body or limbs absent, and caudals increasing in size posteriorly within each autotomic segment. We also present an updated molecular phylogenetic tree of hoplocercines including new samples of Enyalioides rudolfarndti, Enyalioides rubrigularis, both species described in this paper, as well as an updated identification key for species of Hoplocercinae.

Do social groups prevent Allee effect related extinctions?: The case of wild dogs
Angulo E, Rasmussen GS, Macdonald DW, Courchamp F
Frontiers in Zoology 2013, 10:11 (15 March 2013)

Allee effects may arise as the number of individuals decreases, thereby reducing opportunities for cooperation and constraining individual fitness, which can lead to population decrease and extinction. Obligate cooperative breeders rely on a minimum group size to subsist and are thus expected to be particularly susceptible to Allee effects. Although Allee effects in some components of the fitness of cooperative breeders have been detected, empirical confirmation of population extinction due to Allee effects is lacking yet. Because previous studies of cooperation have focused on Allee effects affecting individual fitness (component Allee effect) and population dynamics (demographic Allee effect), we argue that a new conceptual level of Allee effect, the group Allee effect, is needed to understand the special case of cooperative breeders.
We hypothesize that whilst individuals are vulnerable to Allee effects, the group could act as a buffer against population extinction if: (i) individual fitness and group fate depend on group size but not on population size and (ii) group size is independent of population size (that is, at any population size, populations comprise both large and small groups). We found that both conditions apply for the African wild dog, Lycaon pictus, and data on this species in Zimbabwe support our hypothesis.
The importance of groups in obligate cooperative breeders needs to be accounted for within the Allee effect framework, through a group Allee effect, because the group mediates the relationship between individual fitness and population performance. Whilst sociality is associated with a high probability of Allee effects, we suggest that cooperative individuals organized in relatively autonomous groups within populations might be behaving in ways that diminish extinction risks caused by Allee effects. This study opens new avenues to a better understanding of the role of the evolution of group-living on the probability of extinction faced by social species.

Scott R. Loarie, Craig J. Tambling, Gregory P. Asner, Lion hunting behaviour and vegetation structure in an African savanna, Animal Behaviour, Available online 15 March 2013, ISSN 0003-3472, 10.1016/j.anbehav.2013.01.018.
Emerging evidence suggests that male lions are not dependent on female’s hunting skills but are in fact successful hunters. But difficulty locating kills and objectively characterizing landscapes has complicated the comparison of male and female lion hunting strategies. We used airborne Light Detection and Ranging (LiDAR) measurements of vegetation structure in Kruger National Park, combined with global positioning system (GPS) telemetry data on lion, Panthera leo, kills to quantify lines-of-sight where lion kills occurred compared with areas where lions rested, while controlling for time of day. We found significant differences in use of vegetation structure by male and female lions during hunts. While male lions killed in landscapes with much shorter lines-of-sight (16.2 m) than those in which they rested, there were no significant differences for female lions. These results were consistent across sizes of prey species. The influence of vegetation structure in shaping predator–prey interactions is often hypothesized, but quantitative evidence has been scarce. Although our sample sizes were limited, our results provide a mechanism, ambush hunting versus social hunting in the open, to explain why hunting success of male lions might equal that of females. This study serves as a case study for more complete studies with larger samples sizes and illustrates how LiDAR and GPS telemetry can be used to provide new insight into lion hunting behaviour.

Gamelon, M., Gaillard, J.-M., Baubet, E., Devillard, S., Say, L., Brandt, S., Gimenez, O. (2013), The relationship between phenotypic variation among offspring and mother body mass in wild boar: evidence of coin-flipping?. Journal of Animal Ecology. doi: 10.1111/1365-2656.12073
In highly variable environments, the optimal reproductive tactics of iteroparous organisms should minimize variance in yearly reproductive success to maximize the long-term average reproductive success. To minimize among-year variation in reproductive success, individuals can either minimize the variance in the number of offspring produced at each reproductive attempt (classical bet-hedging) or maximize the phenotypic diversity of offspring produced within or among reproductive attempts (coin-flipping).
From a long-term detailed study of an intensively exploited population facing a highly unpredictable environment, we identify a continuum of reproductive tactics in wild boar females depending on their body mass.
At one end, light females adjusted litter size to their body mass and produced highly similar-sized offspring within a litter. These females fitted the hypothesis of individual optimization commonly reported in warm-blooded species, which involves both an optimal mass and an optimal number of offspring for a given mother. At the other end of the continuum, heavy females produced litters of variable size including a mixture of heavy and light offspring within litters.
Prolific heavy wild boar females diversify the phenotype of their offspring, providing a first evidence for coin-flipping in a warm-blooded species.

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