Gregory Stock is a biotech entrepreneur, bestselling author, and was the former director of UCLA School of Medicine's Program on Medicine, Technology and Society. A quote:
Even if half the world's species were lost [during genetic experiments], enormous diversity would still remain. When those in the distant future look back on this period of history, they will likely see it not as the era when the natural environment was impoverished, but as the age when a plethora of new forms---some biological, some technological, some a combination of the two -- burst onto the scene. We best serve ourselves, as well as future generations, by focusing on the short-term consequences of our actions rather than our vague notions about the needs of the distant future.
Read Jon Rappaport's recent article about altering humans (transhumanism) here.