Human Evolution Year 10 Human Biology 2014

Who are we? We are Primates! Kingdom: Animalia Phylum: Chordata Sub-phylum: Vertebrata Class: Mammalia Order: Primate Family: Hominidae Genus: Homo Species: sapiens

Primates? Really? Yup  To be a primate you have the following characteristics: Forward facing eyes (better 3D vision) Grasping hands (prehensile) Nails not claws Opposable first digit Large brain – relative to body size

So who is in our family then? We belong to the family Hominidae Gorillas Orangutans Chimpanzees Us! However we (Homo sapiens) do something that the other primates don’t do…

We can stand upright There are lots of adaptations to our skeleton that allow us to be bipedal (on 2 feet) These include Foramen magnum Vertebral column Pelvis Femur Knee Foot

So who are our ancestors? The Australopithecines This is a different genus to us, but contains at least 6 different species Lived in Africa from 6 to 2MYA Most interesting Australopithecine is Australopithecine afarensis

A. afarenis Lived from 3.7 to 2.5MYA in East Africa Cranial capacity of 400cc Height 1.3m Weight 30kg Walked habitually upright as seen by the Laetoli footprints, shape of the femur and the pelvis

What about our genus? Earliest Homo is the Homo habilis (handy man) Lived in East Africa from 2.4 to 1.4MYA He was a tool maker and scavenged carcasses for meat. This led to a larger brain size

Who came next? After Homo habilis there came Homo erectus (1.9MYA) – Fire man Homo ergaster (1.5MYA) – The wanderer Homo heidelbergensis (400 000 YA) Homo neanderthalensis (200 000 – 70 000YA) Homo sapiens (100 000YA)

Homo ergaster

Out of Africa 15 000 years ago all continental landmasses (except Antarctica) were colonised by Homo sapiens. How do we know this? Mitochondrial DNA analysis Allows us to track migration patterns by studying the mtDNA found in fossil remains.

Summary of evolution Things to look for in our ancestors over time Flatter face (reduced prognathism) Smaller mandible (jaw) Formation of a chin Vertical forehead (to encase a larger frontal lobe) Larger and rounder cranium (to encase a larger brain)