Historically, the freshwater snail fauna of the Mobile River Basin was the most diverse snail fauna in the world. However, dam construction during the early twentieth century left the Basin fragmented, creating conditions which contributed to the extinction of nearly 40 species of snails–the largest extinction event in the history of the continental United States. However, late in 2004, scientists rediscovered three of these presumed extinct species! Things are hopefully looking up for the Mobile River Basin! Click here to read the entire article.