TRACING BACK THE HOBBIT
AFRICA was heady place around 1.75 million years ago, with interspecies sex and a mystery species that has been fingered as the ancestor of one of man’s strangest relatives – 1metre-tall Hobbit.
Homo floresiensis, or the Hobbit as it is known, has been a controversial human relative, since it was discovered in 2003 on island of Flores in Indonesia.
They lived on Flores as recently as 54 000 years ago.
For a long time scientists believed that the species was a direct ancestor of Homo erectus.
Now a study by the Australian National University suggests that the Hobbit most likely evolved from a sister species of Homo habilis, an even earlier ancestor to humans.
The popular theory was that floresiensis evolved from erectus because the hominid was known to have lived on the Indonesian mainland of Java.
“The analyses show that on the family tree, Homo floresiensis was likely a sister species of Homo habilis.
“It means these two shared a common ancestor,” says study leader Dr Debbie Argue of the ANU School of Archaeology & Anthropology.
“It’s possible that Homo floresiensis evolved in Africa and migrated, or the common ancestor moved from Africa, then evolved into Homo floresiensis somewhere.”
Who this shadowy ancestor could be, is not yet clear, although there is a line-up of likely suspects, some with possible dubious sexual preferences.
“It is becoming very clear that there are ghost lineages out there and when you see something like Homo naledi, it is equally primitive to Homo habilis but different in so many ways,” says Professor Lee Berger of Wits University.
Homo naledi, the newest addition to the human tree, was only discovered in 2013.
Professor Francis Thackeray, also of Wits, has studied the Hobbit, homo habilis and homo erectus.
“I found that while the Hobbit was clearly different in size, there was a degree of similarity with specimens attributed to Homo ergaster, which is considered the African version of Homo erectus.
“There has been a debate whether ergaster and erectus are different species.”
He added that he felt there was no clear distinction between homo habilis and homo erectus.
“The work I am doing is that there was a degree of hybridisation of species and gene flow between homo habilis and erectus.”
However another paleoanthropologist, Professor Chris Stringer of the Natural Museum in London, believes that this ancestor might not have been African but still Asian. “There is another view which they may or may not have tested.
“S ma l l e r - b o d i e d , s ma l l - er-brained and more primitive erectus are known from the site of Dmanisi in Georgia at about 1.8 million years old.
“Deriving floresiensis from such an ancestor would require less size reduction and brain size reduction than starting with something like Javanese erectus.
“In addition, we know from other dwarfed mammals that primitive features can seemingly re-evolve, so some evolutionary reversals on the floresiensis lineage could well have occurred,” he says.
“Then there is also the possibility that the mystery species has yet to be discovered.
“A lot of experimentation happened back then, you must remember that there were a lot of alliances being made, there was a lot of hybridisation happening. Things can go away then come back in.
“But it is a complex and fascinating story that we are only at the beginning of,” says Berger.