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Chapter 12. The Earliest Dispersal of the Genus Homo : Homo Erectus and Contemporaries. Introduction . 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.
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Chapter 12 The Earliest Dispersal of the Genus Homo: Homo Erectus and Contemporaries
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.
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 sizedramatically 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.
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.
Olduvai Gorge • Location of a very robust skull discovered by Louis Leakey in 1960. • Dated at 1.4 mya, the cranial capacity is the largest of all the African H. erectus specimens. • The browridge is the largest known for any hominid, but the walls of the braincase are thin. • This differs from Asian H. erectus, in which cranial bones are thick.
The Dmanisi Hominids • The discovery of the Dmanisi materials began in the early 1990s. • The Dmanisi crania have similarities to H. erectus, while some characteristics are different from other hominid finds outside of Africa.
Dmanisi Crania • Dmanisi crania discovered in 1999 and 2001 and dated to 1.8–1.7 mya.Specimen 2282.
Dmanisi Crania • Dmanisi crania discovered in 1999 and 2001 and dated to 1.8–1.7 mya. • Specimen 2280.
Dmanisi Crania • Dmanisi crania discovered in 1999 and 2001 and dated to 1.8–1.7 mya. • Specimen 2700
Dmanisi Cranium • Most recently discovered cranium from Dmanisi, almost totally lacking in teeth (with both upper and lower jaws showing advanced bone resorption).
Questions Raised by the Dmansi Discoveries • Was Homo erectus the first hominid to leave Africa—or was it an earlier form of Homo? • Did hominids require a large brain and sophisticated stone tool culture to disperse out of Africa? • Was the large, robust body build of H. erectus a necessary adaptation for the initial occupation of Eurasia?
Discoveries in Java • Eugene Dubois • 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.
Discoveries in China • Zhoukoudian Cave • “Dragon bones” used as medicine and aphrodisiacs were ancient bones. • 40 male and female adults and children have been found • 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.
Reconstructed Cranium of Homo erectus • (a) Reconstructed cranium of Homo erectus from Lantian, China, dated to approximately 1.15 mya. (b) Hexian cranium.
Africa vs. Asia • East Africa • Thinner cranial bones • Less butressed crania • Homo ergaster? • Daka discovery
Later Homo erectus in Europe • Spain and Italy • Atapuerca • Gran Dolina • Ceprano
Ceprano Homo Erectus Cranium • From central Italy, provisionally dated to 800,000–900,000 ya. • This is the best evidence for Homo erectus in Europe.
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
Acheulian Biface • A basic tool of the Acheulian tradition.
Butchering • A Middle Pleistocene butchering site at Olorgesailie, Kenya, excavated by Louis and Mary Leakey who had the catwalk built for observers.
Acheulian Tools • Acheulian tools, mainly hand axes, found at Olorgesailie in Kenya. Thousands of similar tools were found at-this site.
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.