Researchers looked at 48 fossils of hooved animals from South America . The species - Toxodon plantensis and Macrauchenia patachonica - were first discovered by Charles Darwin inUruguay and Argentina 180 years ago . They are now found in Argentina, Brazil, Paraguay, Bolivia, Peru, Chile, Brazil, Venezuela, Colombia, Ecuador, Panama, Costa Rica, Nicaragua, Honduras, El Salvador, Guatemala, Mexico, Belize Scientists developed new technique for analysing proteins in bones that can reveal links between animals that have been dead for millions of years . The technique can reach further back in time than ancient DNA analysis . They found that the extinct South American animals were related to horses . The new technique - called proteomics - could revolutionise palaeontology .
Researchers looked at 48 fossils of hooved animals from South America . The species - Toxodon plantensis and Macrauchenia patachonica - were first discovered by Charles Darwin inUruguay and Argentina 180 years ago . Palaeontologists have struggled to decide whether the strange looking animals were more closely related to rodents , camels or elephants . Scientists developed new technique for analysing proteins in bones that can reveal links between animals that have been dead for millions of years . The technique can reach further back in time than ancient DNA analysis . They found that the extinct South American animals were related to horses . The new technique - called proteomics - could revolutionise palaeontology .