Archive for the physical anthropology Category

How a Hobbit is Reshaping Our Idea of Human

Posted in H floresiensis, H. erectus, human evolution, paleoarcheology, physical anthropology on February 22, 2010 by Savannah Logsdon-Breakstone

Man has repeatedly tried to define what makes man different from Animals. Physical/Biological Anthropology have latched on to any number of ideas, from tool making to society building in order to define what it means to be human. But Tool-making has since been observed in any number of species, ranging from birds to Octopus- making tool making not only non-exclusive to man, but non-exclusive to mammals. And Society building is actually not uncommon among primates.

Observational Learning isn’t restricted to man, either- in the wild, there is a species of monkeys that lived in two separate areas and had different preference in the type of food eaten. When one was relocated, at first he declined to eat the preferred fruit of his new population, to the point where there was worry that he might grow ill- that is, until he observed this population wash and then eat the new fruit. Afterwards, he mimicked the behavior he had observed, washing the fruit and then consuming it. Same goes with learning to Season food.

And so throughout the history of Anthropology, we have defined and redefined our idea of what makes man man, and our Ideas of how we came to be. Many details about early human history and Prehistory- as well as our pre-human ancestors- are still unknown.

In 2004, some scientists were studying a cave in Flores, Indonesia when they came across some skeletal remains. After studying them, several things stood out. First, that though the skull was the size of a small child, the teeth were those of an Adult. Second, that this individual would have stood at a mere 3 feet tall, but his feet, at about 8 inches, a 70% ratio to his thigh bone. (For comparison, the average adult human’s foot-to-thigh ratio is about 55%.) Third, that the cranial cavity (space in the skull where your brain sits) was only about the size of an orange, but the tools found with the body were relatively advanced.

In part because of the tools found with the Skeleton, some Anthropologists dismissed the Hobbit of Flores as a pathological oddity of either Homo Erectus or modern human origin. They were skeptical that species before H. Erectus would have had advanced enough cognitive abilities to create the tools, and the traditional models of migration seemed to back up that this had to be from H. Erectus or later. Therefore some thought that the Hobbit of Flores may have been from a group of individuals with a genetic predisposition towards a smaller stature or for a number of conditions that cause Dwarfism. Alternatively, that a process of devolution had resulted from H. Erectus, resulting the much smaller stature found in Flores.

However, further study of the bones brought several things to light- first, that the structure of the feet lacked an arch. This is one of the primary indicators of the modern foot. Second, that the wrists of the Hobbit were not consistent with how the modern wrist bones are shaped. Third, and perhaps most strikingly, is the similarities with both Lucy (Australopithicus afarensis) and Homo Habilis.

Previously, the migration charts had placed H. erectus as the first Hominid to leave Africa (There’s a chart showing range at the Hominid Fossil Sites link below). But these new developments regarding the Hobbit (known to scientists as H. floresiensis) suggest that H. habilis or their immediate descendants not only dispersed beyond Africa, but that they developed into a species of hominid that not only lived, but also thrived, in Indonesia until 17,000 years go. For perspective, the date usually used for the emergence of H. sapiens is 120,000 years ago, and the dispersal of H. erectus is about 1-2 Million years ago. The earliest finds related to H. floresiensis are 1.1 million years old, with evidence of tool making dating back to 2 million years, around Flores, suggesting that their ancestors could have left Africa even earlier than H. Erectus.

The Hobbit of Flores is completely reconfiguring our theories of Dispersal of Hominids. But he is also reshaping our ideas on early tool usage. While CTs of the skull found in Flores suggests that he had cognitive ability beyond that of an Ape, his brain was smaller than other species with similar tools to those found. Additionally, the structure and configuration of the wrists would have made the type of tool making used difficult and possibly more painful. The hows- and whys- of them fighting against the inherent physiological difficulties are intriguing, but also intriguing is what this could tell us about the development of cognitive ability as our studies of this species go on.

Resources
(Free/available online unless otherwise noted)

Tufted Capuchins and Macaques (Monkeys; Observational learning/Novel Foods/Deception):
Tool Use by Non-Humans
The Hobbit of Flores (and other early Hominids)
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