Discovery of Ancient Hobbit Fossils in Indonesia Sheds Light on Human Evolution
Researchers excavating at the Mata Menge site on Flores Island, Indonesia, have unearthed fossilized fragments of a small humerus, originally thought to belong to a crocodile. These fragments, dating back around 700,000 years, belong to the diminutive extinct species Homo floresiensis, known as “The Hobbit.”
The Smallest Limb Bone in Human Evolutionary Lineage
The fossilized upper arm bone, or humerus, represents the smallest limb bone known for any member of the human evolutionary lineage. This bone, along with two fossilized teeth found at the site, provides new insights into the origin of Homo floresiensis. The humerus is the first Hobbit bone beyond the cranium identified at Mata Menge, a site previously known for its dental and jaw fossils.
Insights from the Fossils
Based on the bone’s size, researchers concluded that the individual stood about 3 feet 3 inches (one meter) tall. This height is about three inches (6 cm) shorter than the famous 60,000-year-old Homo floresiensis fossil discovered at the Liang Bua cave site, approximately 50 miles (75 km) away. The similarities between the Mata Menge fossils and Homo erectus fossils from Java suggest that Homo floresiensis descended from Homo erectus, a species that arose in Africa and spread to other parts of the world.
Evolutionary Significance and Island Dwarfism
The discovery supports the idea that Homo floresiensis experienced significant body size reduction due to an evolutionary process known as island dwarfism. This phenomenon occurs when larger-bodied mammals, like elephants that also resided on Flores, diminish in size over time due to factors such as periodic food shortages. University of Tokyo paleoanthropology professor Yousuke Kaifu, lead author of the study, notes that Homo floresiensis underwent dramatic body size reduction from the larger-bodied Homo erectus.
The Mata Menge humerus, originally 7.9-8.3 inches (200-211 mm) long, is shorter than the 9.6 inches (243 mm) of the Liang Bua Hobbit and significantly shorter than the average 11.8 inches (299 mm) for modern humans. The fossilized bone, dug up in 2013 and properly identified in 2015, reveals evidence of bone remodeling, indicating it came from an adult.
Homo Floresiensis’ Extinction
The excavation at Mata Menge has uncovered ten Homo floresiensis fossils, including those of two adults and two children, as well as stone tools. These findings suggest that the progenitors of Homo floresiensis were even smaller than the later Hobbits. Homo floresiensis went extinct not long after the arrival of our species, Homo sapiens, in the region.
Archaeology professor and study co-author Adam Brumm of Griffith University’s Australian Research Centre for Human Evolution suggests that our species might have played a role in their extinction. The disappearance of this isolated lineage of archaic hominins coincides with the presence of Homo sapiens in the region.