Evidence that Homo floresiensis survived until just 50,000 years ago. Meaning our ancestors may have met this tiny human species with brains the size of grapefruits.
Rosino, CC BY-SA 2.0, via Wikimedia Commons
The discovery at Liang Bua
In 2003, a joint Indonesian-Australian archaeological team was excavating in Liang Bua, a large limestone cave on the island of Flores. The researchers, including Mike Morwood and Raden Soejono, were initially searching for evidence of the migration of modern humans from Asia to Australia. Instead, they found the partial skeleton of a hominin that was shockingly small. Coded LB1, the specimen belonged to a 30-year-old female who stood only about 1.06 meters (3 ft 6 in) tall.
Initially, the team suspected they had found the remains of a child. The discovery that the bones belonged to a fully grown adult revealed something entirely unexpected. Further analysis showed LB1 had a brain volume of about 400 cubic centimeters, comparable to that of a chimpanzee and much smaller than a modern human's average of 1300 cm³. The unique combination of primitive and derived traits led the scientists to classify it as a new species: Homo floresiensis. The team gave their discovery the nickname "Hobbit," after the small characters from J.R.R. Tolkien's books. Since that first find, parts of at least 11 other H. floresiensis individuals have been recovered from the cave.
A world of tiny elephants and giant storks
The initial dating of the LB1 skeleton suggested it was only 18,000 years old, which would have meant this archaic human species co-existed with Homo sapiens for tens of thousands of years. Extensive geological analysis in 2016 revised the timeline. The skeletal remains of Homo floresiensis are now dated to a window between 100,000 and 60,000 years ago. Stone tools made by the species show they were present in the area from about 190,000 until 50,000 years ago. This later date means an overlap with the arrival of modern humans in the region is still possible.
The layers of sediment in Liang Bua cave also contained the fossils of other unique species. These finds show an isolated island ecosystem. There were pygmy elephants called Stegodon, giant marabou storks (Leptoptilos robustus), vultures, and Komodo dragons. The small size of H. floresiensis and the local Stegodon is likely from insular dwarfism, an evolutionary process where species shrink over time on islands with limited resources. Despite their small brains, H. floresiensis created and used simple stone tools, including flakes, points, and perforators, to hunt these animals. Charred bones suggest they also controlled fire.
💡Fun Facts
The species' nickname, "Hobbit," was coined by the discoverers in reference to their small stature and relatively large feet.
Some scientists initially argued that the LB1 skeleton was a modern human with a growth disorder like microcephaly, but detailed analysis of the skull and wrist bones showed features distinct from *Homo sapiens*.
The disappearance of *Homo floresiensis* from the fossil record around 50,000 years ago coincides with the disappearance of the island's pygmy elephants and giant storks.
Stone tools found elsewhere on Flores, dated to as old as 1 million years, suggest the ancestors of *H. floresiensis* arrived on the island long before modern humans evolved.
