Thursday, November 10, 2011

Ancient DNA casts light on cave art

Pruvost et al., 2011: Fig 2
The prehistoric cave paintings in France were recently made even more famous in Werner Herzog's film "Cave of Forgotten Dreams".  There has been academic debate surrounding these cave paintings, which mostly depict animals.  Some have argued that the paintings have religious or symbolic meaning and are only loosely related to past biodiversity.  Others have maintained that the paintings might be a more literal documentation of the types of animals present in the environment.  However, some of the paintings depict animals, such as leopard spotted horses, that may or may not have existed in pre-domestic, wild populations. 

Enter ancient DNA studies. In a report in PNAS, Pruvost and colleagues describe the results of DNA analysis of 31 wild, pre-domestic horses from Europe.  Their findings indicate that the full range of horse coloration depicted in French cave art were present in pre-domestic horses, based on the distribution of genes linked to coat color expression.  This study suggests that prehistoric cave painters weren't making up animals...these coat coloration actually existed in horses in the wild. 

Tuesday, November 8, 2011

Climate change and endemic species

Sandel et al report in Science on a strong link between the rate of late Quaternary climate change and the geographic distribution of endemic species.

Sandel et al, Figure 1.