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Silvertown J.,Open University Milton Keynes | Cook L.,University of Manchester | Cameron R.,University of Sheffield | Dodd M.,Open University Milton Keynes | And 21 more authors.
PLoS ONE | Year: 2011

Organisms provide some of the most sensitive indicators of climate change and evolutionary responses are becoming apparent in species with short generation times. Large datasets on genetic polymorphism that can provide an historical benchmark against which to test for recent evolutionary responses are very rare, but an exception is found in the brown-lipped banded snail (Cepaea nemoralis). This species is sensitive to its thermal environment and exhibits several polymorphisms of shell colour and banding pattern affecting shell albedo in the majority of populations within its native range in Europe. We tested for evolutionary changes in shell albedo that might have been driven by the warming of the climate in Europe over the last half century by compiling an historical dataset for 6,515 native populations of C. nemoralis and comparing this with new data on nearly 3,000 populations. The new data were sampled mainly in 2009 through the Evolution MegaLab, a citizen science project that engaged thousands of volunteers in 15 countries throughout Europe in the biggest such exercise ever undertaken. A known geographic cline in the frequency of the colour phenotype with the highest albedo (yellow) was shown to have persisted and a difference in colour frequency between woodland and more open habitats was confirmed, but there was no general increase in the frequency of yellow shells. This may have been because snails adapted to a warming climate through behavioural thermoregulation. By contrast, we detected an unexpected decrease in the frequency of Unbanded shells and an increase in the Mid-banded morph. Neither of these evolutionary changes appears to be a direct response to climate change, indicating that the influence of other selective agents, possibly related to changing predation pressure and habitat change with effects on micro-climate. © 2011 Silvertown et al.

Kleewein A.,University of Vienna | Woss G.,Natural History Museum of Vienna
Acta Herpetologica | Year: 2013

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. © Firenze University Press.

Semprebon G.M.,Bay Path University | Rivals F.,Catalan Institution for Research and Advanced Studies | Rivals F.,Institute Catala Of Paleoecologia Humana I Evolucio Social Iphes | Rivals F.,Rovira i Virgili University | And 4 more authors.
Quaternary International | Year: 2015

Microwear analyses have proven to be reliable for elucidating dietary differences in taxa with similar gross tooth morphologies. We analyzed enamel microwear of a large sample of Channel Island pygmy mammoth (Mammuthus exilis) molars from Santa Rosa Island, California and compared our results to those of extant proboscideans, extant ungulates, and mainland fossil mammoths and mastodons from North America and Europe. Our results show a distinct narrowing in mammoth dietary niche space after mainland mammoths colonized Santa Rosa as M. exilis became more specialized on browsing on leaves and twigs than the Columbian mammoth and modern elephant pattern of switching more between browse and grass. Scratch numbers and scratch width scores support this interpretation as does the Pleistocene vegetation history of Santa Rosa Island whereby extensive conifer forests were available during the last glacial when M. exilis flourished. The ecological disturbances and alteration of this vegetation (i.e., diminishing conifer forests) as the climate warmed suggests that climatic factors may have been a contributing factor to the extinction of M. exilis on Santa Rosa Island in the Late Pleistocene. © 2015 Elsevier Ltd and INQUA.

Stara P.,Centro Studi Of Storia Naturale Del Mediterraneo Museo Of Storia Naturale Aquilegia And Geomuseo Monte Arci | Borghi E.,Societa Reggiana di Science Naturali | Kroh A.,Natural History Museum of Vienna
Bulletin of Geosciences | Year: 2016

New material from the Miocene of Italy allows revision of the spatangoid genus Mariania Airaghi, 1901 and proposal of an emended diagnosis. Particularly characteristic, previously overlooked features of the genus include the presence of well-developed phyllodes made up from short, almost equidimensional plates in oral ambulacra II, III and IV. Unlike in other Spatangoidea, where the adoral plates rapidly become elongated towards the margin, they stay short in Mariania and are not constricted halfway between the peristome and the margin. In addition, most species of Mariania possess a characteristic domal profile with steep sides and lack a raised keel in aboral interambulacrum 5. Their petals are wide, open distally and extend almost to the margin. The plastron is not indented behind the episternal plates and the labral plate extends to the second ambulacral plates. Fascioles are missing in all specimens examined. The combination of these morphological features enable the separation of Mariania from the genera Macropneustes, Hypsopatagus and Spatangus, to which members of the genus have been assigned by previous authors. Cladistic analysis carried out to unravel the uncertain systematic position of Mariania failed to find well-supported relationships, but firmly places Mariania within the Brissidina. Most previous family attributions could be, however, ruled out. Based on the available data a placement within Spatangoidea seems most likely, where it takes up an intermediate position between maretiids, loveniids and spatangids. Three different species are identified within the studied sample: Mariania marmorae, the type species of the genus; M. stefaninii sp. nov. from the late Burdigalian-early Langhian of northern Italy; M. comaschicariae sp. nov. from the Burdigalian of Sardinia. These new species are distinguished from M. marmorae by their lower tests, shorter labral plates and shorter petals. Mariania comaschicariae sp. nov. differs from M. stefaninii sp. nov. by its lower test, more anterior apical disc and less numerous plates in the oral anterior paired ambulacra. Test morphology and parent rock sedimentology suggest that Mariania was an epifaunal echinoid, which lived in inner shelf environments, characterized by soft bottoms and a tropical climate. © 2016, Czech Geological Survey. All rights reserved.

Landler L.,Natural History Museum of Vienna | Landler L.,Virginia Polytechnic Institute and State University | von Oheimb P.V.,Justus Liebig University
Molluscan Research | Year: 2013

Y-axis orientation, a movement perpendicular to the shore or coastline, enables aquatic animals to stay in a preferred zone in generally unstable habitats. Such behaviour is a widespread phenomenon in many freshwater and intertidal animal taxa. In the present study, an arena approach was used to test the orientation response of pulmonate freshwater snails. Using this experimental design, Y-axis orientation was shown for the first time in a freshwater snail species, the riverine Chilina patagonica. Some cues, potentially mediating Y-axis orientation, appeared to play no role in the shown orientation behaviour, such as chemical, gravity and humidity cues or a sun compass. Magnetic cues, however, could not be excluded. Since no significant differences in orientation were detected between different size classes in C. patagonica, orientation behaviour may not vary substantially throughout the snail's life history. In contrast to C. patagonica, no consistent orientation response was seen in the related lacustrine species Chilina llanquihuensis. The adaptation of C. patagonica to exhibit orientation along the Y-axis may be driven by the avoidance of high velocities in deeper water. © 2013 Copyright The Malacological Society of Australasia and the Society for the Study of Molluscan Diversity.

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