Ancient tiny people known as hobbits, a product of the so-called “island effect,” evolved from large-bodied Homo erectus hailing from Asia, as a pioneering review of their teeth recently showed.
The new study suggests that a look at the Homo floresiensis, whose remains were discovered in Indonesian island Flores, offers the possibility of a bit of hobbit in humans today. Early modern humans might have interbred with Homo erectus from Asia at a small scale.
The hobbit shrank because of the effects of “insular dwarfism,” where a population evolves given smaller isolated islands and fewer available resources in their limited-range surroundings.
The team, led by project leader Yousuke Kaifu of Tokyo’s National Museum of Nature and Science, compared the hobbits’ teeth with those of 490 Homo sapiens people along with different ancient and already extinct humans.
The toothy findings showed that these ancient humans’ pearly whites are both primitive and modern, and reflect hobbit-related human lineage – distinct from Africa’s, which had evolved in Asia and had spread to other areas.
The teeth and skull of the hobbit closely resembled those of Java Man, a member of Asian Homo erectus. This means that in a relatively short span of time, the hobbit shrank from around five feet to just over three feet. Their brains also turned smaller by more than half, from around 1.8 pounds to a little over 0.8 pound.
The hobbits were estimated to have been around for a while, as indicated by stone tools as old as a million years ago on the island, and to have gone extinct about 13,000 years past.
"I think it is quite possible that they met with early modern humans, who expanded from Africa into Australia around 50,000 years ago," speculated Kaifu.
From there on, the story of the hobbit is shrouded in mystery, whether they were wiped out by disease or mass killings or they were integrated in the Homo sapiens population.
The ancient humans’ teeth continue to puzzle experts, including anthropologist Dr. María Martinón-Torres from University College London. For instance, the molars appeared to have only four cusps compared to five cusps in most primitive humans. Martinón-Torres added that these ancient human species are entirely different from anything she has studied yet they cannot be considered merely as a scaled-down version of humans.
For Kaifu, the study will reverse the trend about the question of evolutionary origin of Homo floresiensis while the hobbit becomes an example of how island isolation could dramatically change the evolutionary process.
The research was published on Nov. 18 in the journal PLOS One.
Photo : Tim Evanson | Flickr