New research raise questions about the identity of Homo floresiensis, or does it?
Anyone who has read or seen the Lord of the Rings trilogy knows that the noble creatures called hobbits played a pivotal role. Recently, a team of anatomists have suggested that real-life hobbits were not the hobbits of Tolkien fame, but cretins known as Homo floresiensis, nick-named hobbits because of their small stature.
In the fall of 2004, Australian and Indonesian paleoanthropologists stunned the archeological world when they published evidence for hobbit-sized hominids that co-existed for a time with modern humans. Fossils recovered on the Flores Island of Indonesia indicate that these hominids stood just over three feet tall with a chimpanzee-like brain size (380 cm3). Their cranial and facial features appear to bear resemblance to Homo erectus and their post-cranial skeleton seems to combine characteristics of theaustralopithecines (like “Lucy”) and H. erectus. The paleoanthropologists who recovered these remains classified them as a new species, Homo floresiensis.
The most remarkable specimen recovered was a nearly complete skeleton of a female that dates to about 18,000 years in age. Other fossil and archeological evidence indicates that H. floresiensisexisted on Flores Island from about 95,000 to 12,000 years ago, when they became extinct. It appears that H. floresiensis, co-existed with modern humans. Still, paleoanthropologists are not sure if the hominids had any contact with human beings.
Archeological evidence and animal remains indicate that H. floresiensis hunted and scavenged the dwarf elephants on the island, as well as rats, fish, snakes, frogs, birds, and tortoises.
The coexistence of H. floresiensis with modern humans and their remarkable behavior—given their small brains—has prompted a minority of paleoanthropologists to argue that these creatures are microcephalic human beings. This interpretation of H. floresiensis has been met by skepticism from many paleoanthropologists.
Recently a team of scientists proposed that the hobbits were modern humans suffering from congenital hypothyroidism. This condition severely limits growth and results in a small brain. Researchers reached this conclusion after analyzing a cast of the only skull of H. floresiensis that has been recovered to date. They point to an enlarged pituitary fossa at the base of the skull behind the nasal cavity. This feature is a diagnostic for endemic cretinism that results from hypothyroidism.
Other paleoanthropologists are unconvinced. They claim that the cast the researchers used in their analysis was a poor replica because the research team did not have access to the actual fossil. This is not uncommon in paleoanthropology. More often than not, researchers have to rely on replicas of the actual fossil specimen. If the replica is poorly made, analyses based on it will be flawed by definition. It appears as if this is the case for the replica that led the team of anatomists to conclude that the hobbits were cretins. The casts of the H. floresiensis skull that are part of the collections of Dean Falk and Ralph Holloway don’t show any evidence for an enlarged pituitary gland.
Peter Brown, who was among the paleoanthropologists who discovered H. floresiensis, also disagrees with the cretin interpretation. He maintains that the actual specimen has a poorly preserved pituitary fossa that doesn’t permit the measurements needed to support the notion that this hominid suffered from hypothyroidism. Brown is one of the few scientists who have seen and handled the actual H. floresiensis skull fossil.
At this juncture, it appears that the original interpretation of the Flores fossils stands. The hobbits aren’t cretins, but remarkable creatures that had close kinship to H. erectus. For a discussion of why it’s unlikely that H. floresiensis were microcephalic humans and of how these hominids fit into RTB’s human origins model, see the article I wrote for our free minimagazine Connections.