Chacoan mara the capybara, and guinea pigs. Chacoan maras are closely related to the other member of the genus "Dolichotis", the Patagonian mara. Maras are the fourth largest rodent in the world after the capybaras, beavers and porcupines . Though the mara may look like a rabbit, the rabbit is not actually a rodent and therefore not as closely related to the mara as one might expect. Chacoan mara The Chacoan mara, Dolichotis salinicola, is a relatively large South American rodent of the cavy family. They are a close relative of the better known Patagonian mara. The Chacoan mara lives in the
Guinea pig that respiratory gas exchange is a combustion, similar to a candle burning. Guinea pigs played a major role in the establishment of germ theory in the late 19th century, through the experiments of Louis Pasteur, Émile Roux, and Robert Koch. Guinea pigs have been launched into orbital space flight several times, first by the USSR on the Sputnik 9 biosatellite of March 9, 1961 – with a successful recovery. China also launched and recovered a biosatellite in 1990 which included guinea pigs as passengers. In English, the term "guinea pig" is commonly used as a metaphor for a subject of