Homo floresiensis really captured my attention this week. I had never studied this species before and was very intrigued by how recently they lived in total isolation. The species was only recently discovered in 2004. H. floresiensis lived on an island called Flores, Indonesia approximately 100,000 to 500,000 years ago. The species was fairly small (only about three feet tall) and had small brains, in addition to other primitive features like long arms and unarched feet. This group is very important because they are descendants of Homo erectus and offer a lot of information on the variation within Homo groups during this period. Scientists suspect that Homo floresiensis were a direct descendent of the first group to leave the African savannah about three million years ago.
Although some scientists first thought that Homo floresiensis were small because they had shrunk from previous species, it is now thought to be more probable that they were small from the beginning. The species they evolved from was similarly sized and H. floresiensis just never got bigger. The discovery of this species is so important because now we know that this region of the planet was populated by ancient human species for much longer than previously thought. The discovery of this species on an island so far from Africa was surprising to anthropologists because of the small brain size of Homo floresiensis. It was not previously thought possible for ancient human species to have left Africa before they evolved bigger brain capacities. Now, in fact, it might be the other way around. Species might have left Africa and from there evolved and developed larger brains. This is a huge discovery and forces scientists to readjust their timelines and theories of how species evolved.
Stone tools dating back to 1.1 million years ago were also found at the site of Homo floresiensis. This was also a bit unexpected given the small brain capacities of the species. While the tools were of the Oldowan style and fairly simple, the formation of these tools still requires a great deal of skill that scientists might not have expected from a group like H. floresiensis. The species also is now holds the title for species that went through the longest period of isolation. They were most likely isolated on that Indonesian island until very close to the disappearance of the species. During all that time, the species did not evolve very much.
Another thing I found very intriguing about Homo floresiensis is that anthropologists have not agreed upon a theory of how the species became extinct. There are two popular theories currently. The first is that a volcano in the region erupted, coating everything with volcanic ash and consequently eliminating H. floresiensis. The second, and more widely agreed upon, theory is that the region was taken over by anatomically modern humans in some way. While the discovery of this species has shed a lot of light on how species evolved in this region, there are still many questions to be answered. I hope that with continued research and digs that anthropologists will be able to learn more about H. floresiensis in the coming years.