Studies have shown that the ancestors of Homo floresiensis were much smaller and lived 700,000 years ago.
Twenty years ago, scientists discovered the fossils of an early human species measuring about 3.5 feet (1.07 meters) tall on the Indonesian island of Flores.
Now, a new study suggests that the ancestors of the tiny Homo floresiensis, nicknamed the “hobbit” after the fictional character in The Lord of the Rings, may have been even smaller.
“We did not expect to find smaller specimens at such an ancient site,” Yusuke Kaifu, the study’s lead author and a researcher at the University of Tokyo, told The Associated Press in an email.
According to the latest research, Posted On Tuesday, the journal Nature Communications reported on a 2016 discovery of a small arm bone and teeth at a site called Mata Menge, about 72 kilometers (45 miles) from the cave.
Analysis of the 88-millimeter (3.5-inch) bone suggests the hobbit’s ancestor was about 1 metre (3.3 feet) tall and lived about 700,000 years ago.
“It makes a compelling case that these were very small individuals,” Dean Falke, an evolutionary anthropologist at Florida State University who was not involved in the study, told the AP.
Scientists have debated how Homo floresiensis originated since its discovery in 2003.
Researchers say the similarities between the Matamenge fossils and Homo erectus fossils from the Indonesian island of Java provide strong evidence that Homo floresiensis descended from that species.
“This means that Homo floresiensis was drastically smaller in size than Homo erectus, which was similar in size to modern humans,” Kai Fu said, adding that the Flores fossils most closely resemble Homo erectus fossils found in Sangiran, Java, dating from 1.1 to 800,000 years ago.
Homo erectus first appeared about 1.9 million years ago and had similar body proportions to modern humans, but a smaller brain.
“The discovery supports the idea that an evolutionary process known as insular dwarfism may have altered the genetics of a large-bodied group of Homo erectus, forcing them to migrate from mainland Asia to the isolated island of Flores about a million years ago or more,” said study co-author Adam Blum, professor of archaeology at Griffith University’s Australian Centre for the Study of Evolutionary Humanity.
Blum added that there was a dramatic decrease in body size on Flores between about 1 million and 700,000 years ago, which gave rise to Homo floresiensis.
“We think the main reason for the size reduction over several generations is that on an island, it is more advantageous to be small than big. Periodic food shortages are likely to be the main selection factor for smaller bodies,” said study co-author Gerrit van den Berg, professor of palaeontology at the University of Wollongong.
The fossil bones found at Mata Menge were so small that the international team initially thought they belonged to a child. However, microscopic examination of the bone samples revealed that they belonged to an adult.
Ten fossils of Homo floresiensis, including those described in 2016, belonging to at least four individuals (two adults and two children), were excavated from the sandstone of Mata Menge, together with stone tools.
Homo floresiensis became extinct shortly after Homo sapiens arrived in the area.
“I think it’s very likely that our species is the culprit,” Brum said. “This isolated lineage of ancient hominins appears to have existed on Flores for a very long time, and disappeared shortly after Homo sapiens established a presence there. That doesn’t seem to be a coincidence.”
