London, May 7 (ANI): In a new research, the fossils of so-called 'hobbits' that date back to between 17,000 and 95,000 years ago, have been analyzed by scientists as belonging to a distinct species of dwarfs who had large feet.
Discovered on the Indonesian island of Flores in 2003 and dubbed 'the Hobbit', the species triggered a worldwide debate about its origins.
In particular, a hard-core cadre of critics said that the skeleton was that of a human who was suffering from microcephaly - a disorder in which the head is much smaller than normal - limiting its brain to 417 cm3, a third the size of the average human brain.
The team, hailing from Indonesia and Australia that discovered the bones argued that the species' brain had probably shrunk owing to its isolation on an island with sparse resources, a phenomenon experienced by other insular animals.
Now, according to a report in Nature News, Eleanor Weston and Adrian Lister of London's Natural History Museum have used brain-scaling data from extinct species of dwarf Madagascan hippopotamuses to show how the Hobbit's brain could easily have reached its proportions.
William Jungers of Stony Brook University in New York and his colleagues report that analysis of the near-complete left foot and parts of the right foot indicate that the animal derives from a more primitive species than was previously believed.
Daniel Lieberman, a Harvard University biological anthropologist, called the results "considerable evidence" that H. floresiensis is a bona fide species.
In the case of H. floresiensis, Jungers said, "It is a real mosaic of primitive and derived features".
The foot was long in relation to lower limb length, he says. The big toe was in line with the other toes, but it was short, whereas the other toes were long.
According to Jungers, "No human on Earth has proportions like that."
He added that the features suggest that H. floresiensis derived from either the earliest Homo erectus, which reached Southeast Asia by about 1.6 million years ago, or the more primitive Homo habilis, thought to have arrived about 1.8 million years ago.
To address the brain-size debate, mammal palaeontologists Weston and Lister examined about 50 skulls of two types of dwarf hippo, some of which lived as recently as about 1,200 years ago.
The researchers scaled brain mass to body mass in these species.
By applying a model of this scaling, they determined that H. floresiensis' brain could have shrunk to about the size known from the lone skull.
"Whatever the explanation for the tiny brain of H. floresiensis relative to its body size, the evidence presented here suggests that the phenomenon of insular dwarfism could have played a part in its evolution," said the researchers. (ANI)