|
Lucie Bazin. (2015).
|
|
. (2015). Phase relationships between orbital forcing and the composition of air trapped in Antarctic ice cores
. Climate of the Past Discussions, 11(2), 1437–1477.
|
. (2015). Regional differentiation and extensive hybridization between mitochondrial clades of the Southern Ocean giant sea spider Colossendeis megalonyx.
. Royal Society open science, 2(7), 140424.
Abstract: Assessing the enormous diversity of Southern Ocean benthic species and their evolutionary histories is a central task in the era of global climate change. Based on mitochondrial markers, it was recently suggested that the circumpolar giant sea spider Colossendeis megalonyx comprises a complex of at least six cryptic species with mostly small and non-overlapping distribution ranges. Here, we expand the sampling to include over 500 mitochondrial COI sequences of specimens from around the Antarctic. Using multiple species delimitation approaches, the number of distinct mitochondrial OTUs increased from six to 15-20 with our larger dataset. In contrast to earlier studies, many of these clades show almost circumpolar distributions. Additionally, analysis of the nuclear internal transcribed spacer region for a subset of these specimens showed incongruence between nuclear and mitochondrial results. These mito-nuclear discordances suggest that several of the divergent mitochondrial lineages can hybridize and should not be interpreted as cryptic species. Our results suggest survival of C. megalonyx during Pleistocene glaciations in multiple refugia, some of them probably located on the Antarctic shelf, and emphasize the importance of multi-gene datasets to detect the presence of cryptic species, rather than their inference based on mitochondrial data alone.
Programme: 1124
|
|
. (2015).
|
|
. (2015). Cephalic kidney and spleen cell culture in Antarctic teleosts. In Ozouf-Costaz C., Pisano. E., Foresti F. & L.F. de Almeida toledo, Eds. Fish cytogenetic techniques. Rau-fin fish and chondrichthyans. pp. 74-81.CRC Press..
|
|
. (2015). The Cryosphere, 9(4), 1373–1383.
|
|
Gadea A., Le Devehat F., Le Lamer A.-C., Charrier M., Boustie J. (2015).
|
|
Gorodetskaya I V, Kneifel S, Maahn M, Thiery W, Schween J H, Mangold A, Crewell S, Van Lipzig N P M, . (2015). Cloud and precipitation properties from ground-based remote-sensing instruments in East Antarctica
. The Cryosphere, 9(1), 285–304.
|
Genthon C, Six D, Scarchilli C, Ciardini V, Frezzotti M, . (2016). Meteorological and snow accumulation gradients across Dome C, East Antarctic plateau
. International Journal of Climatology, 36(1), 455–466.
Abstract: In situ observations show that snow accumulation is ~10% larger 25 km north than south of the summit of Dome C on the east antarctic plateau. The mean wind direction is southerly. Although a slight slope-related diverging katabatic flow component is detectable, the area is an essentially flat (~10 m elevation change or less) homogeneous snow surface. The European Center for Medium-range Weather Forecasts meteorological analyses data reproduce a significant accumulation gradient and suggest that 90% of the the mean accumulation results from the 25% largest precipitation events. During these events, air masses originate from coastal areas in the north rather than from inland in the south. Radiative cooling condensation occurs on the way across the dome and as the moisture reservoir is depleted less snow is dumped 25 km south than north, with little direct impact from the local (50-km scale) topography. Air masses are warmer on average, and warmer north than south, when originating from the coast. This marginally affects the mean temperature gradients. The moisture gradients are more affected because moisture is nonlinearly related to temperature: the mean atmospheric moisture is larger north than south. Significant meteorological and hydrological gradients over such relatively small distances (50 km) over locally flat region may be an issue when interpreting ice cores: although cores are drilled at the top of domes and ridges where the slopes and elevation gradients are minimal, they sample small surfaces in areas affected by significant meteorological and hydrological spatial gradients.
Programme: 411,1013
|
Della Penna Alice, De Monte Silvia, Kestenare Elodie, Guinet Christophe, d'Ovidio Francesco, . (2015). Quasi-planktonic behavior of foraging top marine predators.
. Scientific reports, 5, 18063.
Abstract: Monitoring marine top predators is fundamental for assessing the health and functioning of open ocean ecosystems. Although recently tracking observations have substantially increased, factors determining the horizontal exploration of the ocean by marine predators are still largely unknown, especially at the scale of behavioral switches (1-100 km, days-weeks). It is commonly assumed that the influence of water movement can be neglected for animals capable of swimming faster than the current. Here, we challenge this assumption by combining the use of biologging (GPS and accelerometry), satellite altimetry and in-situ oceanographic data (ADCP and drifting buoys) to investigate the effect of the mesoscale ocean dynamics on a marine predator, the southern elephant seal. A Lagrangian approach reveals that trajectories of elephant seals are characterized by quasi-planktonic bouts where the animals are horizontally drifting. These bouts correspond to periods of increased foraging effort, indicating that in the quasi-planktonic conditions energy is allocated to diving and chasing, rather than in horizontal search of favourable grounds. These results suggest that mesoscale features like eddies and fronts may act as a focal points for trophic interactions not only by bottom-up modulation of nutrient injection, but also by directly entraining horizontal displacements of the upper trophic levels.
Programme: 109
|
