Homo Erectus: An Evolutionary Journey
Homo Erectus
Homo erectus, an extinct hominid, lived between 1.8 million and 300,000 years ago during the Lower and Middle Pleistocene epochs. The classic H. erectus resided in East Asia (China, Indonesia). Fossils discovered in Africa are often classified as a separate species, Homo ergaster. Several European fossils have also been classified as H. erectus, although the current trend is to reserve this name for Asian fossils.[1]
Physical Characteristics and Tools
H. erectus was robust, averaging about 1.80 meters tall. Cranial volume varied between 800 and 1200 cc, showing a steady increase throughout its existence. Distinguishing features included strong brow ridges, a robust jaw lacking a chin, and relatively small teeth. Sexual dimorphism was more pronounced than in modern humans.
Their primary lithic industry was Acheulean, and they likely used fire.
Key Discoveries
Java Man
Between 1891 and 1892, Dutch anatomist Eugène Dubois believed he had found the “missing link” when he unearthed teeth, a skullcap, and a femur resembling a modern human’s near the Solo River in Java, Indonesia. Dubois named his discovery Pithecanthropus erectus[2] (meaning “upright ape-man”) in 1894, but it became known as “Java Man” or “Trinil Man.” In 1940, these remains were finally attributed to the genus Homo (Homo erectus erectus).
Peking Man
In 1921, Swedish geologist Gunnar Anderson discovered a human molar and premolar in Zhoukoudian, China. From 1926, Canadian anatomist Davidson Black led excavations, finding a lower molar in 1927, which he classified as Sinanthropus pekinensis. Two skulls discovered in 1928 led Black to link Sinanthropus with Java’s Pithecanthropus. In the 1930s, German anatomist Franz Weidenreich and others unearthed a significant collection of H. erectus fossils near Beijing, collectively known as “Peking Man.” Weidenreich reclassified these remains as Homo erectus pekinensis in 1940.
The Zhoukoudian cave yielded remains of over 30 individuals who lived between 500,000 and 250,000 years ago. These fossils (14 skulls, 14 lower jaws, 148 teeth, and skeletal fragments) were lost in 1941 during World War II, but Weidenreich had created replicas.
Later excavations at Zhoukoudian uncovered more H. erectus remains, including a complete jawbone in 1959 and skull fragments in 1966. Excavations continued after 1972.
Tools and Fire
Thousands of stone tools were found with Peking Man fossils: choppers, scrapers, knives, hammers, anvils, and points. Bone tools were also found, including shovels, basins, knives, and spikes. Evidence suggests Peking Man used fire for cooking, as ash, charcoal, burnt animal bones, and seeds were found in the cave. However, it’s unclear whether they controlled naturally occurring fire or created it themselves. Construction tools like hammers were also discovered.
Further Discoveries and Evolutionary Path
Other important H. erectus fossils were found in China at sites like Lantian, Yuanmou, Yunxian, and Hexian. Numerous tools were also found at Nihewan and Bose, both in China and other locations of similar age (at least 1 million to 250,000 years old).
The discovery of Homo ergaster in Kenya (considered the African H. erectus and likely the original species) and Homo georgicus in Dmanisi, Georgia (an early H. erectus related to Homo habilis and possibly H. ergaster) helped trace the hominid migration route out of Africa and into Asia.
These findings suggest that Homo erectus evolved in Africa from Homo habilis (or possibly H. ergaster) around 1.7 million years ago and then spread throughout Asia.
The Fate of Homo Erectus
The most recent H. erectus fossils, from Java’s Solo River, date to approximately 130,000 to 50,000 years ago (a potentially debatable dating). H. erectus was a successful species, with a wide distribution and long lifespan.
Scientists debate whether H. erectus was a direct ancestor of Homo sapiens. Late H. erectus populations, like those from the Solo River, may have coexisted with H. sapiens as recently as 50,000 years ago, ruling out their evolution into H. sapiens. While earlier Asian H. erectus populations could have given rise to H. sapiens, it’s now thought that H. sapiens evolved in Africa from African H. erectus populations. H. sapiens then migrated from Northeast Africa to Asia less than 100,000 years ago, potentially encountering the last H. erectus populations.
One species potentially descended from late Homo erectus is the small Homo floresiensis.