The image on the cover of Regular Expressions Cookbook is a musk shrew (genus
Crocidura, family Soricidae). Several types of musk shrews exist, including white- and
red-toothed shrews, gray musk shrews, and red musk shrews. The shrew is native to
South Africa and India.
While several physical characteristics distinguish one type of shrew from another, all
shrews share certain commonalities. For instance, shrews are thought to be the smallest
insectivores in the world, and all have stubby legs, five claws on each foot, and an
elongated snout with tactile hairs. Differences include color variations among their
teeth (most noticeably in the aptly named white- and red-toothed shrews) and in the
color of their fur, which ranges from red to brown to gray.
Though the shrew usually forages for insects, it will also help farmers keep vermin in
check by eating mice or other small rodents in their fields.
Many musk shrews give off a strong, musky odor (hence their common name), which
they use to mark their territory. At one time it was rumored that the musk shrew’s scent
was so strong that it would permeate any wine or beer bottles that the shrew happened
to pass by, thus giving the liquor a musky taint, but the rumor has since proved to be