Anthro 7: Week 6

• -reduced sexual dimorphism
• -more dependence on learning
• -larger brain
• -longer juvenile period
• -longer life span
• -extensive male investment 
• -male-female pair bonds

• -bipedal apes
• -Includes
• ? Early: S. tchadensis; O. tugenensis; A. ramidus
• ? All Australopiths
• ? All Paranthropines
• ? Kenyanthropus

• -Genus Homo
• -Includes
• ? H. ergaster
• ? H. erectus
• ? H. heidelbergensis
• ? H. neanderthalensis

about1.8 mya

• ? Slightly larger brain (but may be proportional to an increase inbody size – this is uncertain)
• ? Teeth are smaller with thinner enamel
• ? Dental arcade is more parabolic (less subnasal prognathism)
• ? Smaller face
• ? Skulls more rounded

• • Creatures appear in Africa with
• ? Large, robust bodies
• ? Long legs and short arms
• ? Slower growth rate
• ? Reduced sexual dimorphism

• -receding forehead
• -no chin
• -narrowing behind eyes

• -horizontal ridge on back skull
• -larger brow ridges
• -smaller, less protruding face
• -higher skull
• -smaller teeth

• • The adults were quite tall (male 6’)
• • Long legs, narrow hips, narrow shoulders
• • Committed bipedality
• • Robust & heavily muscled
• • Shorter arms than earlier 
• • Sexual dimorphism reduced

biting and tearing food(like raw meat)

• • At Swartkrans, burned animal bones found with H.ergaster fossils
• -camp fires made

• -about 1.6 mya
• -called H.erectus

• -thicker skull
• -larger brow ridges
• -sides of skull slope more steeply
• -point at back of skull more pronounced 
• -sagittal keel

Stone tools and bones found in Olduvai. Study of formation of kill sites. Tool marks on bones

Cut marks on a variety of bones. Cut marks on top of carnivore tooth marks.

• Primitive
• -Narrowing of braincase,
• -receding forehead
• -no chin.
• Derived
• -Shorter nose,
• -flatter face,
• -taller skull,
• -smaller jaws and molars,
• -large browridge.
• -Larger brain than earlier humans.
• -Fully adapted for terrestrial life (no trees). -Slower juvenile development.
• -No evidence of spoken language.

• 1.6-1.4 mya ergaster improved upon Oldowan tools.
• -Added stone biface (Mode 2 innovation).
• -Could likely control fire.

Lack of Mode 2 tools related to different cognitive abilities than H. ergaster or to differences in materials available for toolmaking

800-500 kya. Evidence comes from areas as diverse as Spain and Zambia. Possibly coexisted with H. erectus.

• Derived:
• -Larger brains (1200-1300)
• -Higher forehead
• -more rounded skull
• -sides of skull more vertical 
• Ancestral
• -Large brow ridges
• -thick cranial bones
• -large, prognathic face
• -no chin
• -robust bodies

• 35-12 kya.
• -Only 3 feet tall.
• -Very small brains.
• -Isolated on Indonesian island. dwarfism.

• -Big game
• -bones of mammoths and wooly rhino found at base
• -bones have been sorted by body parts

• -300 kya
• -flake tools
• -striking large, symmetrical flakes from core 
• -sharp edge
• -Levallois technique (mode 3)

• 127-30 kya.
• -Europe and western Asia.
• -Mode 3 tools (mousterian).
• -Big-game hunters.
• -Purposeful burial of the dead.
• -shelter in natural rock caves
• -"cave men" of popular culture

• -Bulging faces.
• -Double arched brow ridges.
• -Large cranial capacity (1400).
• -Robust, heavily muscled bodies.

• • H. ergaster originates inAfrica
• • H. ergaster ---->H. erectus inAsia
• • H. ergaster ---> H.heidelbergensis in Africa
• • H. heidelbergensis moves intoAsia & Eurasia
• • H. heidelbergensis----> H.neanderthalensis in Eurasia
• • H. heidelbergensis ----> H.sapiens in Africa
• • H. sapiens moves out of Africaand replaces all

• -dates to 6 mya
• -hominin with a mix of chimpanzee and human traits.
• -the tooth enamel is thick, like that of humans
• -shape and size of their teeth are more chimpanzee-like

• -the oldest hominin ever found, dating from about 7 to 6 million years ago
• -large browridge  
• -relatively flat face,

• -5- 6 milion years ago
• -brain and body size similar to modern chimps
• -large canines compared to humans

• -large sagittal crest
• -flaring zygomatic arches (cheekbones)

• -wide ilium of pelvis
• -Femur - long femoral neck and slant
• -placement of foramen magnum
• -arched foot

Laetoli footprints

• 1. Reduce heat
• -less surface area
• 2. Freeing hands to do things or carry things

• -pronounced sexual dimorphism,
• -postcranial features that are adaptations to arboreality,
• -robust skulls,
• -and small brain sizes (with the exception of A. rudolfensis)

• -The paranthropines are similar to the australopithecines from the neck down, but they had
• -massive cheek teeth and jaws for chewing tough plant materials
• - a skull modified to carry the enormous muscles needed for this type of chewing.