The Rampasasa live on Flores where hobbit fossils were found, but don’t share a genetic history
Achmad Ibrahim/AP Photo
Hobbits took a separate evolutionary path to becoming small than did short, modern-day humans living on the same Indonesian island, a new DNA analysis suggests.
Rampasasa pygmies residing near a cave on Flores that previously yielded small-bodied hobbit fossils inherited DNA from Neandertals and Denisovans but not from any other now-extinct hominid, scientists say, an international team reports in the Aug. 3 Science. The finding provides genetic backup for a fossil-based argument portraying these controversial Stone Age hominids as a separate species, Homo floresiensis, not small-bodied Homo sapiens that could have represented ancestors of Rampasasa people.
Diminutive hobbits, standing roughly a meter tall, lived on Flores from at least 100,000 to 60,000 years ago, with possible ancestors on the island dating to about 700,000 years ago (SN: 7/9/16, p. 6). Some scientists contend that hobbits were actually short humans, not an ancient hominid species (SN: 11/18/06, p. 330). So far, researchers have been unable to extract DNA from hobbit fossils. Comparing hobbit and present-day human DNA would go a long way toward clarifying the evolutionary ID of the half-size Flores hominids.
In the new study, evolutionary geneticist Serena Tucci of Princeton University and colleagues compared DNA from 32 Rampasasa individuals with that of Neandertals, Denisovans and present-day humans around the world. The Flores pygmies got smaller due in part to alterations to genes linked to height and the breakdown of fatty acids in foods, the researchers found.
Still, without hobbit DNA, it’s impossible to say with certainty that Rampasasa pygmies — on average more than 30 centimeters taller than hobbits — inherited no genes from H. floresiensis, says evolutionary geneticist and coauthor Richard Green of the University of California, Santa Cruz. “But we looked hard for [H.] floresiensis ancestry in Rampasasa people and could not find it.”
S. Tucci et al. Evolutionary history and adaptation of a human pygmy population of Flores Island, Indonesia. Science. Vol. 361, August 3, 2018, p. 511. doi:10.1126/science.aar8486.