Clarification

In the article "Scientists Debate RNA's Role At Beginning Of Life On Earth" (R. Lewis, The Scientist, March 31, 1997) on page 14, the following comments should have been attributed to Laura Landweber, an assistant professor of ecology and evolutionary biology at Princeton University: "The ability to isolate new ribozymes from random sequences has fueled a new excitement about the possibility of uncovering early pathways of RNA evolution. Ultimately, this will make the world of possible primordial enzymes accessible even when the molecules are no longer present in modern species."