Prehistory History of South America

aerial view of amazon rainforest, near manaus




paleogeography of northern south america around 105 ma

in paleozoic , mesozoic eras, south america , africa connected in landmass called gondwana, part of supercontinent pangaea. in albian, around 110 ma, south america , africa began diverge along southern mid-atlantic ridge, giving rise landmass of antarctica , south america. during late eocene, around 35 ma, antarctica , south america separated , south america became massive, biologically rich island-continent. during approximately 30 million years, biodiversity of south america isolated rest of world, leading evolution of species within continent.

in last million years since late miocene, south america became connected continent of north america via panama block closed marine bolivar trough, leading great american interchange, interchange of biota both continents. first species discovered have made northward migration pliometanastes, fossil ground sloth species, size of modern black bear. several migrations southern hemisphere undertaken tougher, north american mammal carnivores; fewer species migrated in opposite direction south north. result of intrusion of north american fauna hundreds of south american species became extinct in relatively short time , 60% of present-day south american mammals have evolved north american species. however, species able adapt , spread north america. apart pliometanastes, during irvingtonian stage of mammal land stages, around 1.9 ma, species pampatherium, giant armadillo, ground sloth megatherium, giant anteater myrmecophaga, neogene capybara (hydrochoerus), meizonyx, opossum didelphis, , mixotoxodon followed route north. terror bird titanis discovered south american carnivore species made journey north america.