Human Evolution

Biology

Mr. Young

Paleoanthropologist

• Scientist that studies human evolution from fossils

Hominids

• A group referring to humans and their early ancestors

• Classified on the ability to walk on 2 legs - bipedal

Similar characteristics of humans & other closely related organisms

• Front facing eyes for 3-D vision

Similar characteristics of humans & other closely related organisms

• Opposable thumb or big toe in other primates

Similar characteristics of humans & other closely related organisms

• Dental formula – or number and arrangement of teeth

Similar characteristics of humans & other closely related organisms

• Large cranial capacities relative to body size and complex brain structure

Similar characteristics of humans & other closely related organisms

• DNA that indicates a common ancestry between humans and chimpanzees less than 6 million years ago

• (recent history)

Characteristics of Humans

• Bipedalism – the ability to walk primarily on two legs as a result of “S” shaped pelvis and aligned toes

• Quadrapedal – four limbs to walk

Tim White 1995

• Found remains from 4.4 million years ago (?)

• Ardipithecus ramidus

• Unsure if bipedal hominid

Meave Leakey 1995

• Found remains of hominid dating back 4.2 million years ago

• Australopithecus anamensis

• Head and neck similar to chimpanzee, bipedal

Donald Johanson 1974

• Found remains of hominid dating to 3.2 million years ago

• Australopithecus afarensis – southern ape of Afar Valley

• “LUCY”

• Bipedal, small cranium,

about 3-4 feet tall

Hominids

• Australopithecus Africans – hominid fro 2.3-3 million years ago

• Taller, heavier, and larger cranium

• Australopithecus robustus

• Australopithecus boisei – 1-2.6 million years ago

• Not human ancestors

• Slightly larger cranium than Africans

Homo habilis – handy man

• Hominid from 1.6-2.5 million years ago

• Remains found with stone tools

• Believed to eat meat, enlarged brain for speech

Homo erectus – upright human

• Hominid from 1.8 million -50,000 years ago

• Evidence of homo erectus found first in the Pacific Islands, named Turkana boy

• Later in china, Europe and Africa• Thick skull, large brow ridge, small

forehead, large protruding teeth ,large brain, tall, hunter, used fire to cook meat, lived in caves

Homo neanderthals

• Coexisted with Homo erectus & Homo sapiens

Heavy bones, thick brow ridge, protruding teeth, larger brain than modern humans, average 5 feet tall, lived in caves, stone tools, clothing

• Not human ancestors

• Killed off quickly maybe by disease

Cro-Magnons

• Early modern humans 35,000 years old

• Same sized brain, high forehead, now brow ridge, modern teeth about 6 feet tall