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Chapter 12 The Earliest Dispersal of the Genus Homo: Homo Erectus and Contemporaries

Chapter 12 The Earliest Dispersal of the Genus Homo: Homo Erectus and Contemporaries

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Chapter 12

The Earliest Dispersal of the Genus Homo: Homo Erectus and

Contemporaries

Chapter Outline

• The Life and Times of Homo erectus• The Morphology of Homo erectus• Who Were the Earliest African

Emigrants?• Historical Overview of Homo erectus

Discoveries

Chapter Outline• Technological Trends in Homo erectus• Seeing the Big Picture: Interpretations of Homo

erectus• New Frontiers In Research: Ancient DNA

The Life and Times of Homo erectus• The oldest specimens of H. erectus have been

found in East Africa, they’re dated to approximately 1.8 mya.

• These new East African hominids used the same stone tools as their ancestors.

• They lived in lakeshores, riversides, forests, and grasslands.

• They scavenged and ate at least some meat, as evidenced by cut-marked bone.

The Life and Times of Homo erectus• Homo erectus left Africa about 1.8 mya.• From Kenya they headed north, where we find

them first in the Republic of Georgia, at a site named Dmanisi, in the Caucasus region.

• The next earliest fossil sites are found on the island of Java, Indonesia.

• About 1.6 mya H. erectus was living in three geographically divided regions: East Africa, eastern Europe, and Southeast Asia.

Grade

• A grouping of organisms sharing a similar adaptive pattern.

• Grade isn’t necessarily based on closeness of evolutionary relationship, but it does contrast organisms in a useful way (e.g., Homo erectus with Homo sapiens).

Major Homo Erectus Sites and Localities of Other Contemporaneous Hominids

Major Homo Erectus Sites and Localities of Other Contemporaneous Hominids

Morphology of Homo erectus

• Brain size is related to overall body size.• Body size dramatically increased

compared to earlier hominids. • Cranium had a distinctive shape with a

thick cranial bone and large brow ridges.• Shovel-shaped incisors suggest an

adaptation in hunter-gatherers.

Question

• Compared to earlier members of the genus Homo, Homo erectus was

a) smaller overall.

b) larger overall.

c) more or less the same size.

d) varied.

Answer: b

• Compared to earlier members of the genus Homo, Homo erectus was larger overall.

Dmanisi Crania

• Dmanisi crania discovered in 1999 and 2001 and dated to 1.8–1.7 mya. (a) Specimen 2282. (b) Specimen 2280. (c) Specimen 2700.

The Dmanisi Hominids• The discovery of the Dmanisi materials began

in the early 1990s.• The most informative specimens are four well-

preserved crania, with one recently discovered being almost complete.

• These remains are the best-preserved hominids of this age found anywhere outside of Africa

• They show a mixed pattern characteristics, some quite unexpected.

The Dmanisi Hominids• The Dmanisi crania have similarities to H.

erectus, while some characteristics are different from other hominid finds outside of Africa. The most complete specimen has a less

robust and thinner browridge, a projecting lower face, and a large upper canine.

All three Dmanisi crania have small cranial capacities.

A number of stone tools, similar to early ones from Africa, have been recovered at Dmanisi.

Questions Raised by the Dmansi Discoveries

1. Was Homo erectus the first hominid to leave Africa—or was it an earlier form of Homo?

2. Did hominids require a large brain and sophisticated stone tool culture to disperse out of Africa?

3. Was the large, robust body build of H. erectus a necessary adaptation for the initial occupation of Eurasia?

Discoveries in Java• Six sites in eastern Java have yielded all the H.

erectus fossils found on this island. • Dates range from 1.8 m.y.a. to 1.6 m.y.a.• The Ngandong individuals date from 50,000 to

25,000 y.a. If the Ngandong dates are correct it would

make Homo erectus and Homo sapiens contemporaries.

In Java, no artifacts have been found that can be associated with Homo erectus.

Trinil Skullcap

• The famous Trinil skullcap discovered by Eugene Dubois near the Solo River in Java.

• This is the first time a fossil human was found outside of Europe or Africa.

Sangiran Dome• The Sangiran Dome Team,

composed of researchers from the University of Iowa and the Bandung Institute of Technology, shown here doing a paleoecological analysis of the ancient strata of the Dome.

Discoveries in Peking

• “Dragon bones” used as medicine and aphrodisiacs were ancient bones.

• 40 male and female adults and children have been found near Zhoukoudian. The site was occupied for 250,000 years. 40% of the bones were from individuals less

than 14 years old, 2.6% were from individuals between 50-60 years.

Zhoukoudian

• Composite cranium of Zhoukoudian Homo erectus, reconstructed by Ian Tattersall and Gary Sawyer of the American Museum of Natural History in New York.

Zhoukoudian Cave

Question

• Of the fossil remains at Zhoukoudian,a) 40% belonged to individuals under

14 years old.b) 20% belonged to individuals 50-60

years old.c) nuclear families were clearly

represented.d) all of these choices

Answer: a

• Of the fossil remains at Zhoukoudian, 40% belonged to individuals under 14 years old.

Question

• Discoveries in Dmanisi in the Republic of Georgia have pushed back the time frame for hominids in Europe.

a) True

b) False

Answer: True

• Discoveries in Dmanisi in the Republic of Georgia have pushed back the time frame for hominids in Europe.

Chinese Tools From Middle Pleistocene Sites

Reconstructed Cranium of Homo erectus

• (a) Reconstructed cranium of Homo erectus from Lantian, China, dated to approximately 1.15 mya. (b) Hexian cranium.

Key Homo erectus Discoveries from Asia

Site Dates (y.a.) Human Remains

Ngandong 50–25ky 11 crania

Zhoukoudian 670–410 ky40 individuals; 14 skullcaps, very few postcranial remains

Lantian 1.15 my 2 crania

Sangiran 1.6 myAt least 5 individuals; crania and a few postcranial remains

Discoveries in East Africa• Louis Leakey unearthed a fossil skull at

Olduvai.• An almost complete skull was discovered in

east Turkana.• The most complete H. erectus skeleton ever

found was uncovered in west Turkana.• In Ethiopia, an abundance of Acheulian tools

have been found as well as a robust mandible dating to 1.3 m.y.a.

East African Homo erectus

• East African specimens have thinner cranial bones than those found in Asia.

• Some scientists argue that the African and Asian erectus finds should be classified as separate species.

• The African and Asian populations are separated by more than one million years.

East Lake Turkana, Kenya

• Nearly complete skull of Homo erectus from East Lake Turkana, Kenya; dated to approximately 1.8 mya.

Nariokotome, Kenya

• WT 15000 from Nariokotome, Kenya: the most complete H. erectus specimen yet found.

Key Homo erectus Discoveries from Africa

Site Dates (y.a.) Human Remains

Bouri 1.0 my Well-preserved cranium

Olduvai 1.4 myPartial cranium and a few

postcranial pieces

Nariokotome 1.6 myMostly complete adolescent

Skeleton

E. Lake Turkana

1.8 myOne nearly complete cranium and a few postcranial pieces

Key Homo erectus Discoveries from Europe

Site Dates (y.a.) Human Remains

Ceprano 900–800 ky Well-preserved cranium

Gran Dolina 850–780 ky Fragmentary remains

Dmanisi 1.75my4 crania plus a few postcranial

remains

Time Line for Homo Erectus Discoveries and Contemporary Hominids

Technological Trends in Homo erectus

• Expansion of the brain enabled H. erectus to develop sophisticated tools: Biface - stone that was worked on both sides

and used to cut, scrape, pound, and dig. Thousands of Acheulian hand axes have

been found with remains of large animals.• Homo erectus is seen as a potential hunter and

scavenger.

Small Tools ofthe Acheulian Industry

• (a) Side scraper• (b) Point• (c) End scraper• (d) Burin

Trends in Homo erectus

• Homo erectus liked to travel. • Stone tools found on the island of Flores,

suggest that H. erectus constructed ocean-going vessels.

• Homo erectus embraced culture as a strategy of adaptation.