🦕Intro to Paleoanthropology Unit 6 – Homo erectus and Acheulean Tools

Who Were Homo erectus?

• Early human ancestors that lived during the Pleistocene epoch
• First hominins to leave Africa and spread throughout the Old World (Asia, Europe)
• Considered a direct ancestor of modern humans (Homo sapiens)
• Exhibited a combination of primitive and derived traits compared to earlier hominins
• Had a larger brain size than earlier hominins but smaller than modern humans
• Showed evidence of increased intelligence and complex behavior
• Utilized more advanced stone tools (Acheulean) compared to earlier hominins

When and Where Did They Live?

• Existed between approximately 1.9 million to 110,000 years ago
• Originated in Africa and later spread to Asia and Europe
  • Earliest fossils found in East Africa (Kenya, Tanzania, Ethiopia)
  • Later fossils discovered in Indonesia (Java), China, and the Caucasus region
• Adapted to various environments, including savannas, woodlands, and temperate regions
• Lived during a period of fluctuating climate, including glacial and interglacial periods
• Coexisted with other hominin species, such as Homo habilis and Homo heidelbergensis
• Occupied a wide geographic range, indicating successful adaptations and dispersal capabilities

Physical Characteristics

• Taller and more robust than earlier hominins, with an average height of 5'6" to 5'10" (168-178 cm)
• Had a larger cranial capacity than earlier hominins, ranging from 900 to 1,100 cm³
• Possessed a flatter, less prognathic face compared to earlier hominins
• Exhibited reduced sexual dimorphism compared to earlier hominins
  • Males and females had more similar body sizes and facial features
• Had a more modern postcranial skeleton, with longer legs relative to arms
• Showed evidence of increased brain complexity, such as expanded frontal and parietal lobes
• Possessed a more human-like gait and locomotion, with efficient bipedalism

Behavioral Adaptations

• Utilized more advanced stone tools (Acheulean) for various tasks
  • Hunting, butchering, and processing animal carcasses
  • Woodworking and plant processing
• Showed evidence of increased social complexity and cooperation
  • Possible division of labor based on age and sex
  • Potential for extended family groups and social networks
• Exhibited signs of increased cognitive abilities and problem-solving skills
• May have used fire for various purposes (cooking, warmth, protection)
  • Controversial evidence from some sites (Zhoukoudian, China)
• Engaged in hunting of large mammals, such as elephants and bovids
• Possibly had a more diverse diet, including a greater reliance on meat

Acheulean Tools: What Are They?

• Stone tool industry associated with Homo erectus and other early hominins
• Named after the type site of Saint-Acheul in France
• Characterized by the presence of large, bifacially worked tools
  • Handaxes: Teardrop or oval-shaped tools with sharp edges
  • Cleavers: Large, broad tools with a straight cutting edge
• Also included smaller tools, such as flakes, scrapers, and cores
• Represented a significant advancement in tool-making compared to earlier industries (Oldowan)
• Showed greater standardization and symmetry in tool shape and size
• Required more advanced cognitive abilities and planning to manufacture

Tool-Making Techniques

• Bifacial shaping: Removing flakes from both sides of a stone to create a symmetrical tool
• Soft-hammer percussion: Using a softer material (bone, antler) to strike the stone and remove flakes
  • Allowed for greater control and precision in shaping the tool
• Prepared core technique: Shaping a stone core before removing flakes to create a desired tool shape
• Selection of high-quality raw materials, such as flint, chert, and quartzite
• Use of anvil stones to support the core during flaking
• Possible use of fire to heat-treat stones, making them easier to flake
• Evidence of tool maintenance and resharpening, indicating long-term use and curation

Significance of Acheulean Technology

• Reflected increased cognitive abilities and planning skills of Homo erectus
• Allowed for more efficient acquisition and processing of food resources
  • Hunting of larger animals and processing of carcasses
  • Extraction of bone marrow and other nutrients
• Facilitated the spread of Homo erectus across various environments
  • Adaptability to different ecological niches and food sources
• Served as a basis for the development of later, more advanced stone tool industries
• Provided insights into the social and cultural aspects of early human behavior
  • Potential for social learning and transmission of tool-making skills
  • Possible symbolic or aesthetic significance of some tools (symmetry, craftsmanship)

Legacy and Extinction

• Homo erectus was a successful hominin species that persisted for over 1.5 million years
• Contributed to the evolutionary lineage leading to modern humans (Homo sapiens)
• Acheulean technology influenced later stone tool industries, such as the Middle Paleolithic
• Eventual extinction of Homo erectus may have been due to various factors:
  • Competition with other hominin species, such as Homo sapiens and Neanderthals
  • Climate change and environmental pressures during the late Pleistocene
  • Gradual replacement by descendant species with more advanced adaptations
• Last known fossils of Homo erectus date to around 110,000 years ago in Indonesia
• Legacy of Homo erectus includes the first hominin expansion out of Africa and the development of more advanced stone tool technologies