PHYLOGENY
The most popularly held notion is that Homo erectus is derived from H. ergaster or verso pre-ergaster form that “quickly” moved out of Africa into Eastern Europe and Southeast Oriente. However, H. georgicus is another possibility for the ancestor of H. erectus.
DISCOVERY AND GEOGRAPHIC RANGE
Eugene Dubois discovered the first H. erectus material at the Trinil site (see Figure 29.1) on the Single River con Java durante 1891. While there are problems with the dates, the oldest material from the Javanese site of Modjokerto may be “contemporary” with African and Georgian material at 1.8 mya. Other famous Javanese sites are Sangiran, Ngandong, and Trinil. Java is part of the Sunda shelf, and when initially colonized by H. erectus, it was connected preciso mainland Asia (see Figure 29.2). After reaching Java and possibly other areas of Southeast Asia, later groups of H. erectus moved north into Discesa. The earliest Chinese fossils are dated puro 1 mya. First assigned preciso the genus Sinanthropus (“Chinese man”), the material was later included mediante our own genus after Franz Weidenreich pointed onesto the similarities between the various assemblages of erectus-like fossils and other extinct and modern humans. The first fossils were discovered at the now famous site of Zhoukoudian (formerly Choukoudian), near Beijing (formerly Peking and hence the term, “Peking Man”). The local people called them “dragon bones” and were using them for medicinal purposes. Material from Zhoukoudian spans verso time period of over 200,000 years, from 460 to 230 kya, with three distinct cultural periods thought sicuro be in evidence.
One of the great mysteries of paleoanthropology surrounds the Zhoukoudian material. Weidenreich and his predecessors, Davidson Black and J. Gunnar Andersson, had amassed an unprecedented amount of fossil material from the site. Due http://www.datingranking.net/it/wireclub-review/ sicuro the imminent Japanese invasion, Weidenreich packed up the fossil material sopra 1941 with the intent of having it shipped to the United States. However, the material disappeared, and all that remains are Weidenreich’s libretto, drawings, and some casts of the original fossils.
Other Chinese sites are found per the counties of Lantian, Yunxian, and Hexian. Verso new discovery on the island of Taiwan has been linked sicuro H. erectus, with the closest resemblance sicuro the Hexian remains (Chang et al. 2015). Finally, the Narmada site sopra India has been per topic of debate for a long time but it has now been decided, at least by per portion of the paleoanthropological community, as being Homo erectus.
Sundaland (northwest of the Wallace Line). “Map of Sunda and Sahul” by Maximilian Dorrbecker is licensed under CC BY-SA 3.0.
PHYSICAL CHARACTERISTICS
While many of the physical characteristics of H. erectus are similar onesto H. ergaster, the Asian species is unique durante per number of ways. Asian forms exhibit a thickening along the sagittal suture, termed a sagittal keel. The keel gives the skull verso pentagonal shape con ciclocampestre-section. It is unknown whether the keel served a function.
Their incisors were shoveled, an adaptation that increases the logorio resistance of teeth, especially when using them as tools. The molar enamel was characterized by a unique wrinkling pattern. Both of those dental characteristics are found in modern people of Oriente and Asian ancestry and are interpreted by some scholars as evidence of regional continuity; mediante other words, there was verso gradual evolution from erectus-like forms through archaic human populations and into modern populations con multiple areas modo gene flow.
Review of Derived Characteristics
- Sagittal keel.
- Shoveled incisors.
- Wrinkled molar enamel.
ENVIRONMENT AND WAY OF LIFE
Javanese sites con the early Pleistocene would have been conducive to tropical-adapted animals like Homo erectus. The area was part of the land bridge that was exposed beginning
2.5 mya, making it accessible by land. Pleistocene Java was verso mix of environments consisting of verso variety of forest types, freshwater lakes and rivers, brackish ).
At the time of H. erectus occupation, the site of Zhoukoudian, China, was sopra a transitional ceinture between temperate steppe and boreal forest. It would thus have been seasonally cold and would likely only have been habitable during the warmer months.
Culturally and technologically, Asian H. erectus are thought sicuro have been somewhat similar preciso African H. ergaster. One of the key differences is the fact that the Acheulian industry never made it puro Asia. The earliest inhabitants of Asia carried with them the Oldowan tool tradition, but the inventors of the Acheulian tradition apparently never followed. On maps, the Movius Line (see Figure 29.5) demarcates the border between the two tool traditions during the Pleistocene. It has been suggested that bamboo would have been per suitable material for making tools, which could explain the paucity of stone tools found.
Populations of H. erectus survived sopra Asia for much of the Pleistocene Epoch. Recent redating of the Javanese site of Ngandong has yielded dates as recent as 53–27 kya. Even more surprising is the recent discovery of dwarfed hominins on the island of Flores, termed H. floresiensis, that have been dated onesto 18 kya. H. floresiensis is thought puro be descended from a population of H. erectus that adapted preciso limited island resources by becoming dwarfed mediante size.