17 research outputs found
First evidence for Wollemi Pine-type pollen (Dilwynites: Araucariaceae) in South America
We report the first fossil pollen from South America of the lineage that includes the recently discovered, extremely rare Australian Wollemi Pine, Wollemia nobilis (Araucariaceae). The grains are from the late Paleocene to early middle Eocene Ligorio Márquez Formation of Santa Cruz, Patagonia, Argentina, and are assigned to Dilwynites, the fossil pollen type that closely resembles the pollen of modern Wollemia and some species of its Australasian sister genus, Agathis. Dilwynites was formerly known only from Australia, New Zealand, and East Antarctica. The Patagonian Dilwynites occurs with several taxa of Podocarpaceae and a diverse range of cryptogams and angiosperms, but not Nothofagus. The fossils greatly extend the known geographic range of Dilwynites and provide important new evidence for the Antarctic region as an early Paleogene portal for biotic interchange between Australasia and South America.Mike Macphail, Raymond J. Carpenter, Ari Iglesias, Peter Wil
Arctic freshwater ostracods from modern periglacial environments in the Lena River Delta (Siberian Arctic, Russia): Geochemical applications for palaeoenvironmental reconstructions
Pharmacological characterization of the relaxant effect induced by adrenomedullin in rat cavernosal smooth muscle
Germinal Center Kinases SmKIN3 and SmKIN24 Are Associated with the Sordaria macrospora Striatin-Interacting Phosphatase and Kinase (STRIPAK) Complex
Stable isotope ecology of Miocene large mammals from Sandelzhausen, southern Germany
The carbon, oxygen, and strontium isotope composition of enamel from
teeth of large Miocene herbivorous mammals from Sandelzhausen (MN5, late
Early/early Middle Miocene) in the North Alpine foreland basin, were
analyzed to infer diet and habitat. The mean enamel delta(13)C value of
-11.4 +/- 1.0% (n = 53) for the nine taxa analyzed (including
proboscideans, cervids, suids, chalicotheres, equids, rhinocerotids)
indicates a pure C(3) plant diet for all mammals. (87)Sr/(86)Sr ratios
of similar to 0.710 higher than those from teeth of the western Molasse
Basin (0.708-0.709) seem to indicate preferential feeding of the mammals
in the northeastern Molasse Basin. The sympatric herbivores have
different mean delta(13)C and delta(18)O values which support diet
partitioning and/or use of different habitats within a C(3) plant
ecosystem. Especially the three sympatric rhinoceroses Plesiaceratherium
fahlbuschi, Lartetotherium sansaniense, and Prosantorhinus germanicus
show clear partitioning of plants and/or habitats. The palaeomerycid
Germanomeryx fahlbuschi was a canopy folivore in moderately closed
environments whereas Metaschizotherium bavaricum (Chalicotheriidae) and
P. germanicus (Rhinocerotidae) were browsers in more closed forest
environments. The horse Anchitherium aurelianense was probably a more
generalized feeder than assumed from its dental morphology. The forest
hog Hyotherium soemmeringi has the highest delta(13)C and lowest
delta(18)O value of all analyzed taxa, possibly related to a frugivorous
diet. Most taxa were water-dependent browsers that record meteoric water
delta(18)O values of about -5.6 +/- 0.7% Vienna Standard Mean Ocean
Water (VSMOW). Using a modern-day mean annual air temperature
(MAT)-delta(18)OH(2)O relation a MAT of 19.3 +/- 1.5 degrees C can be
reconstructed for Sandelzhausen. A Gomphotherium subtapiroideum tusk
serially sampled for delta(18)O values does not record a clear pattern
of seasonality. Thus most taxa were C(3) browsers in a forested and
humid floodplain environment in the Molasse Basin, which experienced a
warm-temperate to subtropical climate and possibly low seasonality