Models on WHY? Why we became bipedal (6 hypotheses) Efficient bipedalism as the primary form of locomotion is seen only in hominins.
Primate Evolution Where all the humans, australopithicines, monkeys, apes, homo habilis, tarsiers, lorises, bush babies, Neandertals, hobbit humans, etc. came from… Millions of years ago right after the dinosaurs died…
Paleocene 65 myaPlacental mammal radiation • Earliest primates
Eocene 55-35mya More than 200 recognized fossil primate species.
Eocene 55-35 mya Darwinius, from the Messel site in Germany, discovered in 2009 and dates to ~47 mya. More than 200 recognized fossil species.
Eocene Primates • Foramen magnum position = whether the body is habitually horizontal (like a horse) or vertical (like a monkey). • During the Eocene, the foramen magnum in some primate species was beginning to move from the back of the skull towards the center. • Suggesting…Holding their bodies erect while hopping and sitting, like modern lemurs, galagos, and tarsiers.
Oligocene “Rafting” Africa-> South America ~34 mya early in the Oligocene By this early point in the Oligocene, continental drift had separated the New World from the Old World. New and Old World monkeys branch off here, 35 million years ago.
Oligocene Approximate position of the continents during the beginning of the Oligocene
Oligocene Primates from Fayum Walking with the Beasts (BBC) “Whale Killer” • Apidium • Primitive dental arrangement suggests near or before evolutionary divergence of Old and New World anthropoids • Small, squirrel-like fruit and seed eating, adept at leaping and springing
Egypt’s Fayum • Today, it’s a ~550 square mile lush “oasis” basin in the desert south of Cairo • During the Eocene and Oligocene, the Faiyum was forrested • At the beginning of the Miocene, the Faiyum had become a dry hollow
Oligocene Primates from Fayum cont. • Aegyptopithecus (genus) • 35-33 mya • Largest of Fayum anthropoids, roughly the size of a modern howler monkey (13-18 lbs) • Short-limbed, slow-moving