Monday, September 23, 2013

The Youngest Dryas?

Recently, in my readings about geological--and particularly glacial--history, I came across the term Younger Dryas. This curious name, I learned, applies to a period about 11,000 years ago when glaciers were melting, the climate was warming, and conditions we returning to those we now would consider normal. A relatively brief return to cold conditions at that time was apparently caused by huge amounts of glacial melt water entering the North Atlantic, and blocking warm equatorial waters from reaching Europe. The name Younger Dryas refers to this brief backsliding. The resulting cool temperatures promoted an outbreak in southern Europe of a cold-loving arctic/alpine plant in the genus Dryas. The "younger" name relates to the fact that there were earlier "older" cooling periods in which the little plants expanded their range southward. The combination of names was lent to the later of the unexpected cool periods, and the little Dryas octopetala plant achieved geological fame.

Scanning my photos from last May, I came across the image of the little flower shown above, made somewhere after Acebo and before Molinaseca. Could this be the legendary Dryas, I wondered. Alas, a bit of research indicated that it almost certainly is not. The Dryas of geological fame appears to be Dryas octopetala, and the little flower I photographed obviously has five, rather than eight petals. Also, It appears that the current range of the genus Dryas does not include Spain.

Does anyone know the identity of the plant I photographed? Surely not Dryas octopetala, it appears that it too could be a relative of Dryas, and a member of the Rosaceae--the rose family.