Self-Cloning Seaweed Species Moving W. "Unparalleled Speed" Through Baltic Sea - WP

STOCKHOLM -- Something is happening in the Baltic Sea's underwater forests. A new kind of seaweed is spreading over hundreds of miles in the north. Scientists call it a "super female clone" because most of the new plants are genetically identical females. Called Fucus radicans, or narrow wrack, it has apparently branched off in the past 400 to 1,000 years from Fucus vesiculosus, or bladder wrack, the tree-like vegetation common in the Baltic and other oceans worldwide.

Researchers are concerned about the ecological implications, since the new species -- or subspecies; some scientists dispute the classification -- is smaller and much less ideal for fish, crustaceans, barnacles and other organisms that populate the sea.

The new seaweed has developed at an "unparalleled speed," according to Lena Kautsky, a marine ecologist based in Stockholm. Kautsky worries that the loss of genetic diversity inherent in the spread of the new species could mean that disease or changing conditions will more easily wipe out large swaths of the older seaweed.

In ecological importance and function, bladder wrack is akin to the sea grass beds in the Chesapeake Bay, whose disappearance has withered the shellfish industry. In addition, Bladder wrack is used widely as fertilizer and in nutritional supplements, since its high iodine content is thought to combat hypothyroidism, and another compound helps reduce heartburn.

EDIT

http://www.washingtonpost.com/wp-dyn/content/article/2009/08/02/AR2009080202128.html

a virus or bacillus will find a way to exploit one of its weaknesses and there will be a massive dieoff, something that will likely be repeated at regular intervals.