Human Evolution

What makes us human?

Anthropology has examined evidence from millions of years to develop a theory of the evolution of humanityAnthropologists have studied human biological evolution- fossil evidence (paleontology) and cultural remains (archeology)Scientific advancements now include study of DNA

Theories of Evolution

Origin Myths/CosmologiesGreek – Prometheus

Genesis

Left: Prometheus and AthenaTop: God and Adam

Western examples

Species Classification

Age of Exploration 15th and 16th centuries

New species of plants and animals discovered

New information classified by Carolus Linnaeus (Sweden) during 18th century

Believed that animals and plants were fixed and could not change according to God's work

Later revised this thinking as a result of observation of cross-breeding plants = hybrids

Theories of Evolution

DarwinEvolution theory holds that existing species of plants and animals have emerged over millions of years from simple organisms.

Darwin, On the origin of species, 1859

Charles Darwinyoutube.com/watch?v=CKDSiNf_rLohttp://www. “Darwin's Theory of Evolution: A Brief History”

Theories of Evolution Darwin’s principle of natural selection

“Natural selection is the gradual process by which nature selects the forms most fit to survive and reproduce in a given environment.”

For natural selection to work on a given population, there must be variety within that population and competition for strategic resources.

Theories of Evolution Mendel’s principle of inheritance, 1856

The science of genetics explains the origin of the variety upon which natural selection operates.

By experimenting with successive generations of pea plants, Mendel came to the conclusion that heredity is determined by discrete particles, the effects of which may disappear in one generation, and reappear in the next.http://www.youtube.com/watch?v=7QwTEKhVEDk&feature=related

“How the Body Works: Eye Colour”

Early Primates

Prosimians (65mya)

Monkeys (35mya)

Apes (23mya)

Hominids (5mya)

Early Primates - TraitsCommon physical primate traits:

Dense hair or fur covering

Warm-blooded

Live young

Suckle

Infant dependence

Common social primate traits:

Social life

Play

Observation and imitation

Pecking orderCommon Primate Traits

Primate Family Tree

Crown lemurOrangutan

Pre-hominid Evolution

Reconstruction of Australopithecus

Hominid Evolution

Homo habilis (2.0 – 1.6mya)

H. rudolfensis (2.4-1.6mya)

H. erectus (1.9-27kyBP)

H. heidelbergensis (800-

100kyBP)

H. neanderthalensis (300-

30kyBP)

H. sapiens (130kyBP – present)

Sca

le:

Mill

ions

of

Years

BP

Hominid EvolutionMajor Homo advances:

Brain sizeBetter bipedalismHuntingFire (H. erectus)ToolsBuilt shelters (H. heidelbergensis)Clothing (H. neanderthalensis)Language (Neanderthals?)

Homo habilis

Artist’s representation of a Homo habilis band as it might have existed two million years ago.

612 cc brain

2.3 - 1.6 mya

first toolmaker

prognathic face, brow ridge

probable meat-eater

possibly arboreal

discovered in 1960 by Leakeys

no speech

Homo erectus1891 - Eugene Dubois discovers H. erectus in JavaDubois calls it Pithecanthropus erectus initially, also dubbed “Java Man”dates from 1.9 mya to 27,000 years B.P.994 cc brain size (compare to 612 for H. habilis)

Photograph of Nariokotome boy, an early Homo erectus found near Lake Turkana, Kenya.

Homo erectus – 1.9mya to 27k BPWhy was H. erectus so successful?

Less sexual dimorphism = possible pair bonds, marriageLess hair on body = wearing of furs, other clothingWearing of furs = ability to live further north

Culture is main reason H. erectus was so successful

• organization for hunting• ability to protect against

predators• control of fire?• possible campsites• tools

Distribution of H. erectus

Homo neanderthalensisdiscovered in the Neander Valley (Tal) near Dusseldorf, 1856massive brain--about 1,400cc on averagelarge torso, short limbs, broad nasal passageslater remains show decrease in robustness of the front teeth and face, suggesting use of tools replaced teeth

The skull of the classic Neandertal found in 1908 at La Chapelle-aux-Saints.

What happened to Neanderthals?

H. neanderthalensis coexisted with H. sapiens for at least 20,000 years, perhaps as long as 60,000 years

What happened?

Neanderthals interbred with H. sapiens

Neanderthals were killed off by H. sapiens

H. sapiens drove Neanderthals into extinction by

competition

Homo sapiens

Archaic – 100,000 to 35,000 years BP

Sometimes called Homo sapiens neanderthalensis

Modern – 35,000 years BP to present

Anatomically modern

Cro-Magnon ManCro-Magnon humans

35,000 years B.P. in western Europe to 17,000 years B.P.

1,600 cc cranial capacity

Name comes from a hotel in France

Not a different species, just old Homo sapiens from Europe

Artist’s reconstruction of a Cro-Magnon man