Sirenia

At this moment, Lola turned around and found that she was being watched by two sea cows. "Have you come to take my photo?" They asked. In relief Lola burst into laughter. "Don't laugh," said one of sea cows," We are endangered species." ** Sirenia ** (commonly referred to as sea cows) is an order of fully aquatic, herbivorous mammals that inhabit swamps, rivers, estuaries, marine wetlands, and coastal marine waters. Four species are living, in two families and genera. These are the dugong (1 species) and manatees (3 species). Sirenia also includes Steller's sea cow, extinct since the 18th century, and a number of taxa known only from fossils. The order evolved during the Eocene, more than 50 million years ago.