Just out of curiousity, I have two questions gnawing on my mind right now. I dunno if any of you would care to comment. 1) How do beavers learn how to build dams? How do they feel the urge to build dams? The first is a skill, the second a behavior. Is one or the other a gene thing? Learned from other beavers? A combination of both? Is it a 50-50 thing? 30-70? 2) Cell differentiation. How does a cell know that it's supposed to develop into a hair cell and not a tooth cell or an eye cell? 3) And lastly, why is the sky blue? Nah... Cheers! Serge Need a new email address that people can remember Check out the new EudoraMail at http://www.eudoramail.com