ANTH 3512 Lecture Notes - Lecture 6: Lake Baringo, Sagittal Crest, Foramen Magnum
Document Summary
Sahelanthropus and chadensis: discovered in 2001 from the site of toros menalla in the djurab desert in chad, six specimens dated between 6-7 mya. Dentition: small incisors and molars, intermediate enamel thickness, no cp3 honing complex. Orrorin tugenesis: discovered in 2000 from lake baringo, kenya 6mya, upper/lower limb remains, jaw, isolated teeth. Vertical grove on mesial surface of canine (shared with miocene and living apes) Humorous and phalanges retain adaptations for climbing. Cortical and trabecular bone structure reveal forces induced by bipedal locomotion in humans. Poor ct scan means we cannot answer this question. Multivariate shape analysis= proves early hominin similarities bipedal. Known from a few teeth and fragmentary post cranial remains. A. ramidus (4. 4 mya)- first described in 1994. Ardi relatively complete female skeleton described in 2009: skull: Midfacial prognathism- inferior orbit to inferior nasal aperture- more prognathic than early hominins. Tooth enamel thickness intermediate between pan and austral. Less expensive chewing adaptations than austral: post-cranial.
