HUMAN EVOLUTION

Key Vocabulary Anthropoids – subgroup of primates Hominin (Hominid) – Paleoanthropology – Bipedal Brachiate

What does it mean to be human? Bipedal Larger brain (capable of language and symbolic thought) Also: Reduced jawbones Shorter digestive tract

How determine Bipedalism? Study of skulls  position of foramen magnum

How determine Bipedalism? 1.Study of vertebral column: have arched rather than straight spines 2.Study of pelvic bones Note: Teeth and jaws - rounded rather than rectangular jaws

How determine symbolic thought? Artifacts  ex: tools, and …..….

Ideas to forget! Our biases include: Thinking that complex brain arose before bipedalism That “we’re it” with respect to humanity Facts: Bipedalism appeared first Several species of humans have existed; many co-existed (Note: Greek Mytholgy!)

More Ideas to forget! Common Misconceptions: Humans evolved from chimps Human evolution has been a linear process

The Human Family!

II. Our Heritage: Read about primate characteristics

a. New World monkeys – prehensile tails; nostrils on sides 3. Anthropoids – monkeys and apes b. Old world monkeys – lack a prehensile tail; nostrils point downward

c. Extant non-human groups of apes gibbon gorilla orangutan chimpanzee

III. Early Hominins A. Earliest known hominin (???) – 7 – 6 mya 1. Sahelanthropus tchandensis 2. Found in central africa in 2002

B. Advent of bipedalism What “triggered” bipedalism?

2. Australopithecines (genus Australopithecus) Lived in Africa mya ~ 3 feet (1m) tall Fully bipedal! Some finds……

a. Australopithecus afarensis (Lucy!) mya (1) Discovered by Donald Johanson in Ethiopia (1974) (2) 40% complete!

b. A. afarensis footprints found in Tanzania by Mary Leakey (1978)

4. Another lineage of australopiths - robust australopiths (Genus Paranthropus)

Olduvai Gorge (Tanzania) – site of the discovery of Paranthropus boisei by Richard Leakey

IV. Genus Homo – the human line A. Homo habilis (handy man) 2.4 – 1.6 mya 1. Had a large brain 2. Used stone tools

B. Homo ergaster – mya 1. Substantially larger brain than H. habilis 2. Sexual dimorphism was significantly reduced

C. Homo erectus (upright man) 1. Used stone tools, wore clothes, may have built fires 2. First hominins to migrate out of Africa – 1.8 mya

D. Neanderthals (Homo neaderthalensis) 1. Large thick-browed hominids 2.Lived in Europe, Middle East, and Asia - 200,000 – 30,000 years ago

E. Homo sapiens 1. Appeared in Africa at least 160,000 years ago 2. Analysis of mitochondrial DNA and Y chromosomes suggest that all living humans are descended from common Homo sapiens ancestors who lived in Africa 200,000 – 150,000 years ago

F. Homo floresiensis “The Hobbits”!! 1. Indonesian island of Flores (discovered 2004) 2. Probably co-existed with modern humans – 95,000 – 13,000 years ago

Trend: ↑ Brain Size Selected For! Adult cranial capacity (in cm 3 ) chimpanzees australopithecines early transitional humans modern humans

Uniquely Human Features? ?

V. Cultural Evolution 2. Culture – the accumulated knowledge, beliefs, arts, etc. that are transmitted over generations A. Unique human attributes 1. Language - is controlled by FOXP2 gene B. Three major stages in human cultural evolution (FYI: Enrichment!)

1. Scavenging, hunting, gathering - 2,000,000 years ago

Hadzapi tribe - Tanzania

2. Development of agriculture – 15,000 – 10,000 years ago With agriculture, came permanent settlements and the first cities. Why was agriculture a major factor contributing to the growth of cities?

3. Industrial revolution – 18 th century How did the development of technology lead to an explosive growth of the human population?