Capybara
The capybara ("Hydrochoerus hydrochaeris") is a mammal native to South America. It is the largest living rodent in the world. Also called chigüire, chigüiro (in Colombia and Venezuela) and carpincho, it is a member of the genus "Hydrochoerus", of which the only other extant member is the lesser capybara ("Hydrochoerus isthmius"). Its close relatives include guinea pigs and rock cavies, and it is more distantly related to the agouti, the chinchilla, and the coypu. The capybara inhabits savannas and dense forests and lives near bodies of water. It is a highly social species and can be found in groups as large as 100 individuals, but usually lives in groups of 10–20 individuals. The capybara is not a threatened species but it is hunted for its meat and hide and also for grease from its thick fatty skin, which is used in the pharmaceutical trade.
White-footed rabbit-rat
The white-footed rabbit-rat ("Conilurus albipes") is an extinct species of rodent, which was originally found in woodlands from Adelaide to Sydney, but became restricted to south-eastern Australia. It was kitten-sized and was one of Australia's largest native rodents. It was nocturnal and lived among trees. It made nests filled with leaves and possibly grass in the limbs of hollow eucalyptus trees. The mother carried her young attached to her teats. John Gould said that he removed a baby from a teat of its dead mother. The baby clung tightly to Gould's glove.