Companion to an exhibit about biodoversity hotspots in California. "Defining a hotspot requires understanding a regions species' distributions and endemism (the degree to which species are found only in a given place)." Features descriptions of species in the hotspot areas of Central Valley vernal pools, Mediterranean shrublands, the Sierra Nevada, Cascade range volcanoes, and Klamath-Siskiyou wilderness. Also describes threats (such as population growth and global warming) and related topics. From the California Academy of Sciences.