FOH 2

A possible scenario for human evolution

FOH 2 initially addresses biological evolution. WHY?

FOH 2 initially addresses biological evolution. WHY?

Because especially in the early history of human beings, slow changes in the physical characteristics of humans were the basis for cultural and technological evolution.

5 key characteristics of humans

(key because they distinguish human beings from related species of living things)

- Name them.- Explain WHY each one matters.

• Binocular and color vision• Upright posture• Hands with opposable thumbs• Brain large enough and complex enough to

use hands, tools and language• Language (broader than “speech”) = the

capacity to use symbolic systems to communicate in complex and limitless ways

Hominids?

hominids = the biological FAMILY that includesmodern human beings,their most direct ancestors (related species) or their cousins

Biological classification

KP

CO

FG

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Biological classification

KingdomPhylum

ClassOrder

FamilyGenus

Species

Biological classification

Kingdom: AnimalPhylum: Vertebrates

Class: MammalsOrder: Primates

Family: HOMINIDSGenus: Homo Species: sapiens

Subspecies…

Who’s who in hominids?

Australopithecus afarensis

• “southern ape from Afar region”• Posture, vision, hands, brain more advanced

than other apes• Brain was too small for speech (450 cc)• Used objects it found as tools (to get food)

Who’s who in hominids?

Homo habilis

• “handy man”• Was able to make simple tools• Had larger brain (650 cc), but still not enough

for language

Who’s who in hominids?

Homo erectus

• “upright man”• First to be fully upright• First to have a brain large enough for basic

language ability (750 cc)• Could use fire and had a larger range of tools• First to live in cooler climates

Who’s who in hominids?

Homo neanderthalensis

• “man from the Neander Valley”• Short, muscular, stocky build• Larger brain (1500 cc), skull had heavy brow

ridge, large jaw (quintessential “caveman”)• First to leave evidence of care for the sick and

elderly and deliberate burial of the dead• Used flakes and not just cores of flint for tools

Who’s who in hominids?

Homo sapiens

• “wise man” (modern human beings)• “just right” brain size (1300-1400 cc) – large

enough for language, but easier for childbirth• smaller jaw, teeth, brow, facial features (less

“rugged” in appearance than Homo neander.)• fully mastered fire, had sophisticated tool kit,

created art, left evidence of spiritual beliefs…

For more info, visit website of Human Origins Institute at the Smithsonian Institution: http://humanorigins.si.edu/exhibit/early-human-reconstructionshttp://humanorigins.si.edu/evidence/human-fossils/species

biological technological and cultural evolution

• What was the significance of changes over time in the use of two key technologies?– Flint tools– Fire

Flint tools?

Flint tools?

• Over time, greater efficiency in human use of flint (inches of blade per pound)

• Better tools better hunting and gathering better nutrition and brain development

further improvement of tools

Fire?

Fire?

• Protection from cold, prey wider habitat, power over other animals

• Extends “productive” time past dark• Cooked food: – safer to eat– higher protein– easier to eat (young, old, sick)

Ice Ages

• ~ 200,000 years ago• a period of time when glacial sheets of ice

moved south, covering much of the northern hemisphere and bringing a substantial chilling of temperatures to areas where early humans lived

• significance?

significance of Ice Ages?

Cooler climates forced early humans to adapt to new conditions, esp. through development and use of new tools, search for new sources of food, importance of warmth, shelter, etc.

Cultural evolution?

What practices, beliefs, ways of living, interacting, etc. developed over time make early humans seem more “like us?”