BlancanThe Blancan North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 4,750,000 to 1,806,000 years BP, a period of . It is usually considered to start in the early-mid Pliocene Epoch and end by the early Pleistocene. The Blancan is preceded by the Hemphillian and followed by the Irvingtonian NALMA stages. As usually defined, it corresponds to the mid-Zanclean through Piacenzian and Gelasian stages in Europe and Asia.
Quaternary extinction eventThe latter half of the Late Pleistocene to the beginning of the Holocene (~50,000-10,000 years Before Present) saw extinctions of numerous predominantly megafaunal species, which resulted in a collapse in faunal density and diversity across the globe. The extinctions during the Late Pleistocene are differentiated from previous extinctions by the widespread absence of ecological succession to replace these extinct megafaunal species, and the regime shift of previously established faunal relationships and habitats as a consequence.
GlyptotheriumAutomatic taxobox | fossil_range = Early Pliocene-Early Holocene (Blancan-Rancholabrean) (Ensenadan-Lujanian)~ | image = Glyptotherium.jpg | image_caption = G. texanum, National Museum of Natural History | taxon = Glyptotherium | authority = Osborn, 1903 | type_species = Glyptotherium texanum | type_species_authority = Osborn, 1903 | subdivision_ranks = Other Species | subdivision = * G. cylindricum (Brown, 1912) | range_map = Glyptodon and Glyptotherium Distribution Map2.
EremotheriumEremotherium (from Greek for "steppe" or "desert beast": ἔρημος "steppe or desert" and θηρίον "beast") is an extinct genus of giant ground sloth in the family Megatheriidae. Eremotherium lived in the southern North America, Central America, and northern South America from the Pliocene, around 5.3 million years ago, to the end of the Late Pleistocene, around 10,000 years ago. Eremotherium was widespread in tropical and subtropical lowlands and lived there in partly open and closed landscapes, while its close relative Megatherium lived in more temperate climes of South America.
Ground slothGround sloths are a diverse group of extinct sloths in the mammalian superorder Xenarthra. Ground sloths varied widely in size, with the largest genera Megatherium and Eremotherium being around the size of elephants. Ground sloths are a paraphyletic group, as living tree sloths are thought to have evolved from ground sloth ancestors. The early evolution of ground sloths took place during the late Paleogene and Neogene of South America, while the continent was isolated.
MegalonychidaeMegalonychidae is an extinct family of sloths including the extinct Megalonyx. Megalonychids first appeared in the early Oligocene, about 35 million years (Ma) ago, in southern Argentina (Patagonia). There is, however, one possible find dating to the Eocene, about 40 Ma ago, on Seymour Island in Antarctica (which was then still connected to South America). They first reached North America by island-hopping across the Central American Seaway, about 9 million years ago, prior to formation of the Isthmus of Panama about 2.
SlothSloths are a Neotropical group of xenarthran mammals constituting the suborder Folivora, including the extant arboreal tree sloths and extinct terrestrial ground sloths. Noted for their slowness of movement, tree sloths spend most of their lives hanging upside down in the trees of the tropical rainforests of South America and Central America. Sloths are considered to be most closely related to anteaters, together making up the xenarthran order Pilosa. There are six extant sloth species in two genera – Bradypus (three–toed sloths) and Choloepus (two–toed sloths).
Columbian mammothThe Columbian mammoth (Mammuthus columbi) is an extinct species of mammoth that inhabited the Americas as far north as the Northern United States and as far south as Costa Rica during the Pleistocene epoch. The Columbian mammoth descended from mammoths that colonised North America around 1.5 million years ago, that later hybridised with woolly mammoths during the Middle Pleistocene, prior to 420,000 years ago. The Columbian mammoth was among the last mammoth species, and the pygmy mammoths evolved from them on the Channel Islands of California.
MegalonyxMegalonyx (Greek, "great-claw") is an extinct genus of ground sloths of the family Megalonychidae, native to North America. It evolved during the Pliocene Epoch and became extinct during the Quaternary extinction event at the end of the Pleistocene-Early Holocene, living from ~5 million to ~13,000 years ago. The type species, M. jeffersonii (also called Jefferson's ground sloth), the youngest and largest known species, measured about in length and weighed up to .
Great American InterchangeThe Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which land and freshwater fauna migrated from North America via Central America to South America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor and bridged the formerly separated continents. Although earlier dispersals had occurred, probably over water, the migration accelerated dramatically about 2.
