Human origins (Homo)

Defining characteristics of genus homo

1. Hand morphology

2. Encephalization

3. Stone tool use

4. Tooth size reduction

Hand morphology

Increased manipulation, able to have more precise/powerful grip, ability to apply pressure at finger tips

Encephalization

Larger brain size relative to bodysize, increased motor units for manipulation/control in hands

encephalization is reflected in hand morpholgy/tool use

Stone tool use

Oldowan technology/Mode 1 (found at olduvai gorge)

tools can be used for primary tools/sources of flakes

the increased hand manipulation ability allows for use of tools

Tooth size reduction

Smaller molars/premolars, more similar to what we see in modern day humans.

*potentially a product of stone tool use

(eating different foods like meat instead of vegetation)

Homo habilis (pliestocene)

Discovered at olduvai gorge & turkana basin

Dates from east africa 2.8-1.4 mya

Introduction of the genus homo

Distinguishing features of homo habilis

robust face, more gracile than australopiths, large back teeth, parallel arcade, larger than australopiths

Cranial capacity of homo habilis

500-800 cubic centimeters

Morphology of homo habilis

Low frontal bone, supraorbital torus (brow-ridge)

Decreased molar/premolar, increased movement at thumb joint, obligate biped

No chin

Homo Erectus

Discovered – Indonesia, China, Europe, North Africa.

Found in 1891 by Eugene Dubois 

Skeletal elements recovered : Calotte, postcranial elements, teeth.

Cranial capacity/Weight of H.erectus

700-1250 cm3

80-150 lb

5'-6 ft tall

Why is H.erectus an important find?

• Earliest significant representation of homo 

• First to leave Africa – obligate bipeds 

• Cranial capacity is larger, but relative brain size is some of early homo 

• Preyed on by predators

Distinguishing features of H.erectus

Thick superorbital torus 

Thick cranial bones

Nuchal torus 

Sagittal Keel 

Wider cranial base 

Low frontal bone 

Large incisors relative to molars

Projecting nose (first hominin to have this)

Large incisors//canines (anterior teeth)

Oldowan stone tool industry

-oldest at 2.5 MYA, as old as 3.3

Olduvai gorge, Tanzania 

Types : Choppers for scraping 

Acheulean stone tool industry

1.6-200,000 ya

• Recovered and named after ST. Acheul on the Somme river in France, 1847

Bifaced hand axes

KNM-WT 1500 (Turkana/Nariokotome boy)

Skeletal elements recovered: Facial bones, vertebrae 

Stone tool industry: Acheulean

*Single most complete Homo erectus we have 

Found in the west 

KNM-WT body morphology

Cranial capacity: 880 cm3

Height: 5’9

Weight : 100lb+ 

Sex: Male 

Age: 8-12 yrs (9-10 in lecture)

Importance of KNM-WT

Most complete skeleton found in species

-Skeletal development 

-Modern human spine/ribcage 

Differences Homo erectus vs premodern/archaic

Increased brain size

Rounder brain case

Vertical nose

Less angled occipital

Homo Heidelbergensis

Transitional species from H.erectus to other premoderns

Discovered - Heidelberg,Germany

No DNA recovered

Dates- 850,000-200,000 ya

Kabwe “Broken hill”

Limestone cave, Kabwe Zambia

1,300 cranium capacity

Kabwe ancestoral features

Suborbital tori

Low cranial vault

Occipital torus

Kabwe derived traits

Occupital less angled

Thin cranial vault bones

Modern occipital

Bodo

600,000 ya

earliest find of H. Heidlbergenisis in africa

earliest conclusive evidence of canibalism

Sima de los Huesos “bone pit”

600,000-400,000 ya

Earliest evidence of Neanderthal lineage

Nuclear DNA places them closer to neaderthals than denisovans

Early premodern

Evidence of fire found in china/south africa

Stone tool industry: Acheulin with levaollis technique

Structures/living in caves

Schoningen spears

The old man of La chapelle

Cave in france

Recovered a skull/post-cranial elements

60,000 ya

Antemortem tooth loss/resorption

Arthritis