Another skillfully distilled effort showing the same even-handed selection of anecdote and contemporary scientific data as Wild Cousins of the Dog (1973) and . . . of the Cat (1975). Hopf moves easily through theories of origin and development (via the Bering Strait crossover), characterizes both extant and extinct groups, and includes informed speculations--and some alarming predictions--about the future of modern species. Basic organizing information is introduced clearly and reinforced strategically, and relatively sophisticated concepts (evolution as irregular rather than linear, relationships between ungulate toe-counts and extinction rates) are made accessible.