TY  - JOUR
A1  - Sommer, Robert S.
A1  - Kalbe, Johannes
A1  - Ekstrom, Jonas
A1  - Benecke, Norbert
A1  - Liljegren, Ronnie
T1  - Range dynamics of the reindeer in Europe during the last 25,000 years
JF  - Journal of biogeography
N2  - Aim To understand the role and significance of the reindeer, Rangifer tarandus (Linnaeus, 1758), as a specific indicator in terms of late Quaternary biogeography and to determine the effects of global climate change on its range and local extinction dynamics at the end of the Ice Age.
 Location Late Pleistocene/early Holocene range of reindeer over all of central and western Europe, including southern Scandinavia and northern Iberia, but excluding Russia, Belarus and the Ukraine.
 Methods Radiocarbon-dated subfossil records of R. tarandus from both archaeological and natural deposits younger than 25,000 years were assembled in a database. The distribution area was divided into six representative regions. The C-14 dates were calibrated and plotted chronologically in maps in order to compare presence and absence and regional extinction patterns from one region to another.
 Main conclusions The late Quaternary record for reindeer in Europe during the last 25 kyr shows a climate-driven dispersal and retreat in response to climate change, with regional variations. The collapse of the mammoth steppe biome did not lead to the local extinction in Europe, as in the case of other megafaunal species. Rangifer tarandus co-existed for about 3000 years during the Late Glacial and early Holocene with typical temperate species such as red deer and roe deer in non-analogue faunal communities. The regional extinction at the end of the Pleistocene coincides with the transition from light open birch/pine forests to pine/deciduous forests.
KW  - Climate change
KW  - environmental change
KW  - extinction
KW  - global change
KW  - late Quaternary
KW  - Pleistocene/Holocene transition
KW  - Rangifer tarandus
KW  - reindeer
Y1  - 2014
U6  - https://doi.org/10.1111/jbi.12193
SN  - 0305-0270
SN  - 1365-2699
VL  - 41
IS  - 2
SP  - 298
EP  - 306
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Georgy, C.
A1  - Ekström, S.
A1  - Hirschi, R.
A1  - Meynet, G.
A1  - Groh, J. H.
A1  - Eggenberger, P.
T1  - Wolf-Rayet stars as an evolved stage of stellar life
JF  - Wolf-Rayet Stars : Proceedings of an International Workshop held in Potsdam, Germany, 1.–5. June 2015
N2  - Wolf-Rayet (WR) stars, as they are advanced stages of the life of massive stars, provide a good test for various physical processes involved in the modelling of massive stars, such as rotation and mass loss. In this paper, we show the outputs of the latest grids of single massive stars computed with the Geneva stellar evolution code, and compare them with some observations. We present a short discussion on the shortcomings of single stars models and we also briefly discuss the impact of binarity on the WR populations.
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-88097
SP  - 229
EP  - 232
ER  - 
TY  - JOUR
A1  - Meynet, G.
A1  - Georgy, C.
A1  - Maeder, A.
A1  - Ekström, S.
A1  - Groh, J. H.
A1  - Barblan, F.
A1  - Song, H. F.
A1  - Eggenberger, P.
T1  - Physics of massive stars relevant for the modeling of Wolf-Rayet populations
JF  - Wolf-Rayet Stars : Proceedings of an International Workshop held in Potsdam, Germany, 1.–5. June 2015
N2  - Key physical ingredients governing the evolution of massive stars are mass losses, convection and mixing in radiative zones. These effects are important both in the frame of single and close binary evolution. The present paper addresses two points: 1) the differences between two families of rotating models, i.e. the family of models computed with and without an efficient transport of angular momentum in radiative zones; 2) The impact of the mass losses in single and in close binary models.
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-87971
SP  - 183
EP  - 188
ER  -