Influenza Virus (electron microscope image)“A new study provides the first inventories of microbial capabilities in nine very different types of ecosystems, ranging from coral reefs to deep mines.”

The microbial study produced … evidence that viruses — which are known to be ten times more abundant than even microbes — serve as gene banks for ecosystems. This evidence includes observations that viruses in the nine ecosystems carried large loads of DNA without using such DNA themselves …. The viruses probably transfer such excess DNA to bacteria during infections, and thereby pass on “new genetic tricks” to their microbial hosts. The study also indicates that by transporting the DNA to new locations, viruses may serve as important agents in the evolution of microbes.

- Science Daily: Mar. 14, 2008: Link.