Pygmy hippopotamus population that freely breeds in zoos around the world. Between 1970 and 1991 the population of pygmy hippos born in captivity more than doubled. The survival of the species in zoos is more certain than the survival of the species in the wild. In captivity, the pygmy hippo lives from 42 to 55 years, longer than in the wild. Since 1919, only 41 percent of pygmy hippos born in zoos have been male. While the common hippopotamus was known to Europeans since classical antiquity, the pygmy hippopotamus was unknown outside its range in West Africa until the 19th century. Due
Spined pygmy shark and insular slopes. It may also be found over outer shelves, but avoids central ocean basins. The range of this species does not overlap that of the pygmy shark, which has a similar ecology, and is also largely separate from that of the cookiecutter shark. One of the world's smallest sharks, the spined pygmy shark attains a maximum recorded length of for males and for females. This species has an elongated, spindle-shaped body with a long, bulbous, moderately pointed snout. The eyes are large, with the upper rim of the orbit almost straight. Each nostril is preceded by a short