Study shows that the ancestors of Homo floresiensis were even shorter and lived 700,000 years ago.
Twenty years ago, scientists discovered fossils of an early human species measuring about 1.07 meters tall on the Indonesian island of Flores.
Now, a new study suggests that the ancestors of diminutive Homo floresiensis, nicknamed “Hobbits” after fictional characters in The Lord of the Rings, were even shorter.
“We did not expect to find smaller individuals in such an ancient site,” the study’s lead author, Yousuke Kaifu of the University of Tokyo, told The Associated Press in an email.
The latest discoveries, Published on Tuesday in the journal Nature Communications, follow the 2016 discovery of a small arm bone and teeth at a site called Mata Menge, about 72 km (45 miles) from the cave where the first fossils were unearthed.
Analysis of the 88 mm (3.5 inch) bone suggests that the ancestors of Hobbits were about 1 meter (3.3 feet) tall and lived about 700,000 years ago.
“They convincingly demonstrated that these were very small individuals,” Dean Falk, an evolutionary anthropologist at Florida State University who was not involved in the research, told the AP.
Scientists have debated the origins of Homo floresiensis since the species was discovered in 2003.
Similarities between the Mata Menge fossils and Homo erectus fossils from the island of Java in Indonesia provide strong evidence that Homo floresiensis descended from that species, the researchers said.
“This means that Homo floresiensis experienced a dramatic reduction in body size from the large-bodied Homo erectus, whose body size was similar to that of us modern humans,” Kaifu said, adding that the Flores fossils were more similar to fossils from Homo erectus dated from 1.1 million to 800,000. years ago from Sangiran in Java.
Homo erectus first appeared about 1.9 million years ago, possessing similar body proportions to modern humans, but with a smaller brain.
“The discovery lends support to the idea that an evolutionary process known as island dwarfism tinkered with the genetics of a group of large Homo erectus that somehow managed to move from the Asian landmass to the isolated island of Flores, perhaps a million from years ago. there is or more,” said archeology professor and study co-author Adam Brumm of the Australian Research Center for Human Evolution at Griffith University.
They drastically reduced their body size on Flores between about a million and 700,000 years ago, giving rise to Homo floresiensis, Brumm added.
“It is thought that the main reason for this reduction in size over many generations is that being small has more advantages than being large on an island. Periodic food shortages are probably the main selective force for smaller body size,” said Gerrit van den Bergh, professor of paleontology at the University of Wollongong and co-author of the study.
The fossilized bone discovered in Mata Menge was so small that at first the international team of researchers thought it must have belonged to a child. A microscopic examination of a sample of the bone, however, showed that it was from an adult.
Ten Homo floresiensis fossils, including some described in 2016, from at least four individuals – two adults and two children – were excavated from sandstone at Mata Menge, along with stone tools.
Homo floresiensis became extinct shortly after the arrival of Homo sapiens in the region.
“I think our species was most likely to blame,” Brumm said. “This isolated lineage of archaic hominids appears to have existed on Flores a long time ago and then disappeared shortly after it became known that Homo sapiens had established a presence in the region. This hardly seems like a coincidence.”
This story originally appeared on Aljazeera.com read the full story
