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Muri, Switzerland

Matter A.,University of Bern | Neubert E.,Natural History Museum Bern | Preusser F.,University of Stockholm | Rosenberg T.,University of Bern | Al-Wagdani K.,Saudi Geological Survey
Quaternary International | Year: 2015

Shallow lakes and sabkha deposits are evidence of past periods of higher groundwater table than today, and hence reflect increased humidity in the Rub' al-Khali, the large desert in the southern part of the Arabian Peninsula. Reported here are the observations made during four expeditions into this remote area in combination with luminescence dating constraining the age of the deposits. The results presented extend the spatial coverage of evidence and show that most of the deposits correlate to MIS 5 (ca. 130-70. ka) and the Early/Mid Holocene (ca. 11-5.5. ka). A single sample points towards potentially more humid conditions during the transition MIS 4/3 (ca. 65-55. ka). The presence of the mussel Unio in some of the deposits attributed to MIS 5 is indirect evidence for the presence of fish in the lakes, which must have supported a rich and diverse fauna (and probably also flora). Together with other evidence, this demonstrates that a number of small persistent lakes were spread across the Rub' al-Khali for at least some of the time. These lakes would not only have been a potential source of freshwater but could also have provided an additional and easy accessible food source via the fish for humans migrating through the area. The presented palaeoenvironmental data underlines that parts of MIS 5 represent a time window of opportunity for a potential expansion of modern humans across Arabia. © 2014 Elsevier Ltd and INQUA. Source

Hofmann B.A.,Natural History Museum Bern
Chimia | Year: 2010

Meteorites are fragments from solar system bodies, dominantly asteroids. A small fraction is derived from the Moon and from Mars. These rocks tell a rich history of the early solar system and range from solids little changed since the earliest phases of solid matter condensation in the solar nebula (chondrites) to material representing asteroidal metamorphism and melting, impact processes on the Moon and even aqueous alteration near the surface of Mars. Meteorites are very rare. Currently many meteorites result from searches in Antarctica and the hot deserts of North Africa and Arabia. The present high find rate likely represents a unique short-term event, asking for a careful management of this scarce scientific resource. © Schweizerische Chemische Gesellschaft. Source

Tegetmeyer C.,University of Greifswald | Thoma M.,Natural History Museum Bern | Arbeiter S.,University of Potsdam
Journal of Ornithology | Year: 2012

The globally threatened Aquatic Warbler Acrocephalus paludicola is a Palearctic-African long-distance migrant that undergoes a complete moult while wintering in Africa. Little is known about the timing of moult and the birds' mobility during moulting periods. We conducted the first study on the moult of Aquatic Warblers, in the Djoudj area of Senegal, West Africa. Wing moult scores from 36 to 90 and raggedness scores from 0 to 25 were recorded in December and January. No moulting Aquatic Warblers were caught after January. Body-feather moult was observed during and shortly after wing moult until January. We conclude that Aquatic Warblers follow the typical sequence of passerine moult, with remige moult starting in October or November. To find out how moult affects their mobility, we measured the net distance that Aquatic Warblers equipped with radio transmitters travelled in 15-min intervals. In our small sample of eight birds, the mean path length was 34 m, and there was no obvious difference between the path lengths in moulting and non-moulting individuals. We conclude that, possibly, moult does not affect the mobility and flight ability of Aquatic Warblers in general. Further research is needed to locate other wintering grounds, e. g. in the Inner Niger Delta, and reproduce our study in other populations. © 2012 Dt. Ornithologen-Gesellschaft e.V. Source

Thoma M.,Natural History Museum Bern | Taschler A.,Neue Jonastrasse 87c
British Birds | Year: 2013

On 5th May 2011, a Birnaculated Lark Melanocorypha bimaculata was discovered in the canton of Ticino, southern Switzerland. This was the first record for Switzerland and only the second for central Europe. Despite the proximity of its breeding grounds in Turkey and the Middle East, the Birnaculated Lark is still an extremely rare vagrant in Europe, with just 22 records from nine countries. We describe the Swiss record and discuss the species' status as a vagrant in Europe, its occurrence patterns and status in captivity. © British Birds 2013. Source

Two new species, Pteromalus briani sp. n. and P. janstai sp. n., with unusual characters are described from the Central Plateau and the Alps in Switzerland, respectively. P. briani sp. n. is remarkable in that it has the metatibia quite abruptly expanded before the middle. This type of modification of the hind tibia is unique within the Pteromalidae and probably also the entire Chalcidoidea. It is also very rare in other parasitic wasps, where it is suspected to be associated with pheromone glands. The species is a gregarious endoparasitoid of pupae of Vanessa atalanta (Linnaeus) and Aglais urticae (Linnaeus), two common butterflies (Lepidoptera: Nymphalidae) in Europe. It is furthermore a koinobiont parasitoid ovipositing in an early larval stage of the host. The other species, P. janstai sp. n., shows a flattened mesosoma. A dorsoventrally depressed body is a unique feature within the genus Pteromalus, but known from a number species in unrelated genera and subfamilies. The two records demonstrate that it is possible to discover entirely new species with extraordinary characters even in one of the taxonomically most thoroughly explored parts of the world. © 2015, Hannes Baur. Source

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