Giant hutia
The giant hutias are an extinct group of large rodents known from fossil and subfossil material in the West Indies. One species, "Amblyrhiza inundata", is estimated to have weighed between , big specimens being as large as an American black bear. This is twice as large as the capybara, the largest rodent living today, but still much smaller than "Josephoartigasia monesi", the largest rodent known. These animals were probably used as a food source by aboriginal humans. All giant hutias are in a single family, Heptaxodontidae, which contains no living species; this grouping seems to be paraphyletic and artificial, however.
Rodent
Order Rodentia (from Latin, "rodere", to gnaw)While rodents are not the most seriously threatened order of mammals, there are 168 species in 126 genera that are said to warrant conservation attention in the face of limited appreciation by the public. Since 76 percent of rodent genera contain only one species, much phylogenetic diversity could be lost with a comparatively small number of extinctions. In the absence of more detailed knowledge of species at risk and accurate taxonomy, conservation must be based mainly on higher taxa (such as families rather than species) and geographical hot spots. Several species of rice rat have become extinct since the 19th century, probably through habitat loss and the introduction of alien species. In Colombia, the brown hairy dwarf porcupine was recorded from only two mountain localities in the 1920s, while the red crested soft-furred spiny rat is known only from its type locality on the Caribbean coast, so these species are considered vulnerable. The IUCN Species Survival Commission writes "We can safely conclude that many South American rodents are seriously threatened, mainly by environmental disturbance and intensive hunting".