Remains of a long-extinct diminutive hominid species have been discovered on the Indonesian island of Flores. Pieces of jaw bone and several teeth were found and are believed to belong to at least one adult and two children from a species pre-dating all other known hominid species of that size.
According to the findings published in Science, the early species is believed to have inhabited flat grassland similar to other known early hominids:
[...] various lines of evidence suggest the hominins inhabited a savannah-like open grassland habitat with a wetland component. The hominin fossils occur alongside the remains of an insular fauna and a simple stone technology that is markedly similar to that associated with Late Pleistocene H. floresiensis.
This is the second time that a new species of early hominid has been discovered on the island following the 2004 discovery of Homo floresiensis, also known as the “hobbit” for its small size.
While Homo floresiensis is thought to have gone extinct around 50,000 years ago, scientists have dated volcanic ash and calcite that surrounded the new fossilized remains and estimate them to be between 100,000 and 60,000 years old. That would mean that this newly found species could have overlapped with the arrival of Homo sapiens.
The new specimens are believed to belong to an ancestor species of Homo floresiensis, although there still exists some debate about the exact classification of previously known hobbit specimens. According to the Science article describing the new find, some archeologists believe the hobbit remains could belong to a dwarf Homo erectus specimen:
It is a matter of controversy whether this primitive form, dated to the Late Pleistocene, evolved from early Asian Homo erectus and represents a unique and striking case of evolutionary reversal in hominin body and brain size within an insular environment.
It has been speculated that the hominids became smaller than other hominid species through a phenomenon known as insular dwarfism which can occur when populations are isolated and therefore have less genetic diversity. This potentially new hominid species could shed light on the mechanisms of human evolution, or at the very least, give a deeper understanding of the evolution of human ancestors which took off on separate branches on the tree of life.