Biology 201 Dr Edwin De Mont Evolution of

Biology 201 Dr. Edwin De. Mont Evolution of Man Linked to Ardi papers. St. Francis Xavier University

Primates Two suborders (1) Strepsirhini - Lemurs (2) Haplorhini Six Families…. 6. Hominidae Hominini -Gorillas, chimpanzees, orangutan and humans St. Francis Xavier University

Evolution of Hominins 5 -7 million years ago global temperature dropped. Tropical forests in Africa broken in mosaic of forests and vast savannah. African apes started to graze for food. Upright posture gave better view of predators and free hands for food gathering and bipedal locomotion evolved. St. Francis Xavier University

Bipedal locomotion Skeletal adaptations for bipedal locomotion -Spinous processes reduced. - Vertebral column curved. - Vertebrae larger at base. - Femur angled – puts feet under centre of mass. St. Francis Xavier University

Evolution of Hominins A. Gibbons Science 326, 36 -40 (2009) Published by AAAS Introductory Video St. Francis Xavier University

Ardipithecus ramidus 4. 4 million year old skeleton from Ethiopia “Facultative” biped Flexible hand Published by AAAS Opposable toe St. Francis Xavier University

Evolution of Hominins Video: The Analysis of Ardipithecus ramidus--One of the Earliest Known Hominids Published by AAAS St. Francis Xavier University

Evolution of Hominins Paleobiological Implications of the Dentition Used as a slicing weapon in social conflicts Social behavioural changes long before tools were used. Honing occurs in canine Published by AAAS Humans Ardi Chimp St. Francis Xavier University

Evolution of Hominins Paleobiological Implications of the Dentition Thick enamel – food abrasive from terrestrial feeding Thin enamel – ripe fruits Red : Thick Enamel Blue: Thin Enamel Published by AAAS Humans Ardi Chimp St. Francis Xavier University

Evolution of Hominins The Pelvis and Femur: The Emergence of Upright Walking Ilia different shape in chimps – won’t allow repositioning of hips during leg lift-off Ischial surfaces angled showing hamstrings undergone transformation Man Chimpanzee Lucy Ardi Published by AAAS St. Francis Xavier University

Evolution of Hominins A. Gibbons Science 326, 36 -40 (2009) Published by AAAS St. Francis Xavier University

Image source Evolution of Hominins There is general acceptance of five Homo species. Fossils of Homo habilis (2. 4 -1. 5 million years ago) demonstrate the presence of Broca's area (an area of the brain devoted to speech). St. Francis Xavier University

Image source Evolution of Hominins Homo erectus (1. 8 -300, 000 years ago) was the first member of the genus to migrate from Africa to Europe, China, and Indonesia. H. erectus used more sophisticated tools and was the first to utilize fire. St. Francis Xavier University

Image source Evolution of Hominins H. heidlebergeinsis appeared 500, 000 years ago. St. Francis Xavier University

Image source Evolution of Hominins H. neanderthalensis (230, 000 -30, 000 years ago). Neanderthal man was specialized for life in the cold climate of Europe and the Middle East. Neanderthals were the first known Homo species to bury their dead. St. Francis Xavier University

Evolution of Hominins H. sapiens arose in Africa 195, 000 years ago. H. sapiens produced fine works of art. Fully modern humans were present about 30, 000 years ago. St. Francis Xavier University