American Scientist

To the Editors:

Although biodiversity globally has been in decline for many years, local species richness may in fact be stable or increasing despite the loss of native species because of the addition of nonnative invasive species. If biodiversity (locally) is in and of itself a good thing, regardless of the species present, the case for conservation couched in terms of preserving biodiversity becomes more difficult.

In the article “The Biodiversity Conservation Paradox” (March–April), Mark Vellend makes the point that “scientific credibility can be safeguarded by keeping values out of the quantification of biodiversity as much as possible.” I agree. However, I think that values are appropriate in the overall discussion of conservation and preservation. Unique communities are worth preserving simply because they are unique. Even if there is no net change in species richness in a local community, the replacement of endemic species with ubiquitous invasive species diminishes the value of the community from both an intellectual and aesthetic perspective. These are good enough reasons to support conservation and habitat preservation.

Jaime E. Dickerson, Jr.
Fort Worth, TX