The extinct archaic human species Homo floresiensis, formerly of Indonesia, left behind fully-grown adult skeletons that famously measure at a diminutive height of three and a half feet tall, which compelled scientists to naturally nickname them “hobbits,” after the iconically pint-sized “Lord of the Rings” creatures.
These hobbits mysteriously disappeared from their primary habitat — not the Shire, but the Liang Bua cave on the island of Flores — about 50,000 years ago. Now, an international team of researchers have published a new paper in the Nature science journal Communications Earth & Environment with a new theory of what led to their demise: an extreme drought that lasted for years, they say, that most likely forced them to flee and possibly led to their extinction.
“The ecosystem around Liang Bua became dramatically drier around the time Homo floresiensis vanished,” said Michael Gagan — paleoclimatologist, the study’s lead author, and a professor at the University of Wollongong in Australia — in a statement about the study. “Summer rainfall fell and river-beds became seasonally dry, placing stress on both hobbits and their prey.”
Researchers first encountered evidence of Homo floresiensis back in 2003 when the skeleton of this short stack humanoid was found in the wide-mouth limestone Liang Bua cavern, which is festooned with large stalagmites and stalactites. About a dozen more skeletal remains were later found, further cementing the discovery.
The hobbits lived about 100,000 to 60,000 years ago on the island, according to researchers. The remains of pygmy elephants, their primary prey, were also found in the caves.
Upon their discovery, scientists debated whether these hobbits were the result of island-induced dwarfism or if they arrived at the island already short in height. Researchers also debated why they disappeared. Did they vanish due to increased competition from modern humans who arrived on the island around the same time they disappeared?
Regardless of any possible impact from our arrival, the current study argues that a drying climate on the island made life more difficult. The scientists determined this by studying the chemical composition of stalagmites, which grow droplet by mineralized water droplet at a time. Analyzing chemicals within these limestone formations enabled researchers to reconstruct past rainfall and climate conditions around the Liang Bua cave. In addition, they also studied oxygen isotopes levels within the teeth of elephants, who relied on fresh river water for hydration.
Analysis from the cave formations and animal teeth revealed that the decline of ready freshwater and the elephant population dwindling happened around the same time when Homo floresiensis vanished from the archaeological record (though a few people still think they exist, like the mythological Big Foot.) Drier conditions started about 76,000 years ago, and reached their worst point around 61,000 to 55,000 years ago — around the same period when modern humans started coming to the island.
“It’s possible that as the hobbits moved in search of water and prey, they encountered modern humans,” said Gagan in the statement. “In that sense, climate change may have set the stage for their final disappearance.”
More on Homo floresiensis: Scientist Says There May Be a Species of Hobbit-Like Humanoids Hiding on an Island