Topic ID #8472 - posted 8/30/2010 2:27 AM
Jennifer Palmer
Webmaster
True Causes for Extinction of Cave Bear Revealed: More Human Expansion Than Climate Change
Jennifer Palmer
Webmaster
True Causes for Extinction of Cave Bear Revealed: More Human Expansion Than Climate Change
ScienceDaily (Aug. 25, 2010) — The cave bear started to become extinct in Europe 24,000 years ago, but until now the cause was unknown. An international team of scientists has analysed mitochondrial DNA sequences from 17 new fossil samples, and compared these with the modern brown bear. The results show that the decline of the cave bear started 50,000 years ago, and was caused more by human expansion than by climate change.
"The decline in the genetic diversity of the cave bear (Ursus spelaeus) began around 50,000 years ago, much earlier than previously suggested, at a time when no major climate change was taking place, but which does coincide with the start of human expansion," says Aurora Grandal-D'Anglade, co-author of the study and a researcher at the University Institute of Geology of the University of Coruña.
According to the research study, published in the journal Molecular Biology and Evolution, radiocarbon dating of the fossil remains shows that the cave bear ceased to be abundant in Central Europe around 35,000 years ago.
"This can be attributed to increasing human expansion and the resulting competition between humans and bears for land and shelter," explains the scientist, who links this with the scarce fossil representation of the bear's prey in the abundant fossil record of this species.
Read the rest of the article here.
ScienceDaily (Aug. 25, 2010) — The cave bear started to become extinct in Europe 24,000 years ago, but until now the cause was unknown. An international team of scientists has analysed mitochondrial DNA sequences from 17 new fossil samples, and compared these with the modern brown bear. The results show that the decline of the cave bear started 50,000 years ago, and was caused more by human expansion than by climate change.
"The decline in the genetic diversity of the cave bear (Ursus spelaeus) began around 50,000 years ago, much earlier than previously suggested, at a time when no major climate change was taking place, but which does coincide with the start of human expansion," says Aurora Grandal-D'Anglade, co-author of the study and a researcher at the University Institute of Geology of the University of Coruña.
According to the research study, published in the journal Molecular Biology and Evolution, radiocarbon dating of the fossil remains shows that the cave bear ceased to be abundant in Central Europe around 35,000 years ago.
"This can be attributed to increasing human expansion and the resulting competition between humans and bears for land and shelter," explains the scientist, who links this with the scarce fossil representation of the bear's prey in the abundant fossil record of this species.
Read the rest of the article here.
Post ID#18088 - replied 8/30/2010 7:41 PM
marehart
Interesting topic given the apparent trophy status of the animal to HSN. They do seem a bit over confident in their findings:
The researcher's conclusions do assume that they have a representative sample. This is something that might be doubtfull given the age range, the geographic range and the limited number of skeletons-- less than two per ten thousand years per geographic region. You know what happens when you 'assume'......
|
Next topic: "Parched English fields reveal ancient sites" |
|
Previous topic: "Nasca Lines may be giant map of underground water sources" |
|
Looking for something else? Show recent posts in Discussion |