Saving Bison, Losing Tigers

As every reader of this magazine knows since the anthrax-by-mail episode in October 2001, anthrax is caused by a bacterium, Bacillus anthracis, which can infect the skin, gut, or lungs and produce a toxin that is rapidly fatal; vaccination or antibiotics can prevent this infection. Scientists also know that B. anthracis is an ubiquitous soil organism that affects livestock all over the world, with the exception of small island countries, those on the east coast of Arabia, and for some reason, Sweden. It causes sporadic deaths in cattle, sheep, horses, and goats, which ingest a certain amount of soil with the grass they pull up to eat.