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 found both in peri-urban environments as well as in rural regions, for example, in South Kivu. They are also frequently held in rural households in Iringa Region of southwestern Tanzania. The use of guinea pigs in scientific experimentation dates back at least to the 17th century, when the Italian biologists Marcello Malpighi and Carlo Fracassati conducted vivisections of guinea pigs in their examinations of anatomic structures. In 1780, Antoine Lavoisier used a guinea pig in his experiments with the calorimeter, a device used to measure heat production. The heat from the guinea pig's respiration melted snow surrounding the calorimeter, showing