Tiny ‘hobbit’ human fossils discovered in Indonesia date back 700,000 years

Two decades after researchers unearthed an ancient race of “hobbit” humans on the Indonesian island of Flores, a new team has discovered fossils that are even smaller and significantly older.

The original hobbit fossils, named after the fictional race from The Lord of the Rings, were dated to between 60,000 and 100,000 years ago. The species, known as Homo floresiensis, was named after the island of Flores where they were found. Scientists estimate these hobbits stood around 3.5 feet tall. To date, all known hobbit fossils have been discovered on Flores.

The newly discovered fossils were found at a site called Mata Menge, approximately 72 kilometres from the Liang Bua cave where the first hobbit bones were uncovered. These remains are astonishingly ancient, dating back an incredible 700,000 years.

An international team of scientists contributed to the analysis of the bones, with their findings published in Nature Communications on Tuesday. The study revealed that the bones represent the ancestors of Homo floresiensis, who were even shorter in stature.

From a partial jawbone, six teeth, and a meticulously reconstructed arm bone, researchers estimated that these hobbit ancestors were approximately 2.4 inches shorter than their descendants. This size difference could be attributed to natural variation within the species, similar to what is observed in modern humans. However, the findings clearly indicate that Homo floresiensis maintained its diminutive size over an extraordinarily long period of time.

This is significant because scientists are still uncertain as to why or how this human species evolved to be so small.

One theory posits that the hobbits may have evolved from an earlier, taller human species known as Homo erectus, which is believed to have been the first early human species to migrate out of Africa.

Fossils of Homo erectus have been discovered across Asia, including as far east as China and the Indonesian island of Java. Some researchers suggest that the hobbits descended from a group of Homo erectus who became isolated on the island of Flores. Over time, these isolated humans are thought to have undergone significant size reduction, a process known as insular dwarfism, according to the Smithsonian National Museum of Natural History.

This process is known as “island dwarfism,” which occurs due to long-term isolation on an island with limited food resources. Over time, evolution favours smaller members of a species who can survive on less food. A related example of this phenomenon is the now-extinct pygmy elephant of Flores, which underwent a similar shrinking process on the same island as the hobbits.

“Perhaps, there was no need to be large-bodied, which requires more food and takes longer to grow and breed,” explained lead study author Yousuke Kaifu, a professor at the University of Tokyo, to CNN. “The isolated island of Flores had no mammalian predators and other hominin species, so small body size was OK.”

However, another prominent theory suggests that the hobbit humans were already small when they first arrived on Flores. Advocates of this theory argue that Homo floresiensis may have descended from Homo habilis, a human species even older than Homo erectus.

Tuesday’s study seems to support this theory, as it indicates that the ancestors of the hobbits were shorter than their descendants and may have grown taller over time. If the Homo erectus theory were accurate, one would expect the ancestors of Homo floresiensis to be taller, with the fossil record showing them gradually shrinking over time.

The primary challenge with the Homo habilis theory is that fossils from this species have only been discovered in Africa, with no evidence to suggest they ever migrated to Asia.