Opening details

In 2004, anthropologists on the Indonesian island of Flores discovered the remains of a miniature hominin called Homo floresiensis, nicknamed “The Hobbit” for its resemblance to characters from The Lord of the Rings. Now, another team of researchers has discovered teeth and a fossilized forearm that they say belong to the smallest known human ever identified. Scientists have not yet named the new species, but the findings will help shed more light on the evolution of these tiny humans, and perhaps will do so in the future.

This very rare example supports our hypothesis that the ancestors of Homo floresiensis were extremely small in body size. However, when looking at the very small proportions of this limb bone, it is now clear that the early “hobbit” ancestors were much smaller than we previously thought.
“These are the most striking examples of the evolution of the fossils,” said archaeologist Adam Brumm, of the Australian Research Centre for Human Evolution at Griffith University in Brisbane.

The remains of H. floresiensis, found in 2004, were determined to be about 60,000 years old, about 10,000 years before the species went extinct. The researchers found that these tiny humans were grew to only 109 centimeters.

The new study details teeth, a jaw, and part of a humerus (the long bone of the forearm) belonging to at least four individuals of H. floresiensis. 700,000 years agoEach fossil was smaller than the remains found in 2004.

The large bone on the right belongs to H. floresiensis, the small bone on the left belongs to its smaller ancestor / Photo: Yousuke Kaifu

Although the newly discovered humerus has been partially destroyed over time, its characteristic shapes allow us to restore its proportions and thus determine its exact length. It is only 8.79 centimeters, allowing the team to conclude that it belongs to an adult human. 100 centimeters.

This 700,000-year-old adult arm bone is not only shorter than that of Homo floresiensis, but is also the smallest arm bone known from hominin fossils anywhere in the world.
Brumm adds.

People on the island of Flores existed until about 50,000 years ago, around the time modern humans appear in fossil remains in Southeast Asia. Perhaps these tiny hominins became what they are as a result of this island dwarfism —the process by which species with access to fewer resources shrink in size in proportion to the resources available to them. For example, H. floresiensis shared the island of Flores with Stegodon, a very small extinct species of elephant.

What do Homo floresiensis fossils mean for human evolution?

The prevailing theory today is that “hobbits” descended from Homo erectus, which came from Java. In their study, the team noted similarities between the teeth of older species and those of smaller humans, some 700,000 years old. The team also cited stone tools found in the Soa Basin as evidence that H. erectus was isolated on Flores about 1 million years ago and shrank in size over the next 300,000 years. But this is far from true.

The authors say the findings raise the possibility that floresiensis evolved from Homo erectus’ Indonesian ancestors, although it remains puzzling that the wrist bones of floresiensis are more similar to those of Afarian australopithecines and chimpanzees than to humans. Perhaps early erectus ancestors still had these wrist bones, or (which seems much less likely to me) floresiensis may have redeveloped this more primitive wrist anatomy.
said anthropologist Chris Stringer of the Natural History Museum in London, and he had no connection to this latest paper.

Stringer added that if the process of dwarfism occurred on Flores, it could also have occurred on other islands in the region, such as Sumbawa or Sulawesi, so we can check that. More fossils could help explain how short people appeared in our family tree and why they disappeared. For now, the 700,000-year-old arm bone appears to offer a new record for the smallest ancient human.