Homo floresiensis abandoned Liang Bua — a cave this small-bodied human species had occupied for around 140,000 years — during severe drought between 61,000 and 55,000 years ago, according to new research.
Reconstruction of Homo floresiensis. Image credit: Elisabeth Daynes.
Homo floresiensis was first discovered in 2003 in Liang Bua on the Indonesian island of Flores.
Dubbed the hobbit due to its tiny stature, the species challenged prevailing theories of human evolution.
It disappeared from the fossil record around 50,000 years ago, but its fate has remained an enigma.
“In 2003, excavations at the Liang Bua rock shelter uncovered the skeletal remains of a previously unknown small-bodied hominin species, Homo floresiensis,” said University of Wollongong’s Honorary Professor Mike Gagan and his colleagues.
“The Homo floresiensis occupation interval was initially dated to 95,000-12,000 years ago, raising the possibility of interaction with early modern humans (Homo sapiens) in Island Southeast Asia, with implications for the extinction of the species.”
“Following revisions to the site’s stratigraphy and chronology, however, all Homo floresiensis skeletal remains now date to about 100,000-60,000 years ago.”
“The associated stone artifact record and assemblage of large fauna typically found with Homo floresiensis end at about 50,000 years ago.”
“The revisions indicate that their disappearance from the record preceded modern human arrival at Liang Bua around 46,000 years ago, marked by a notable shift in the assemblage of raw materials for stone tool making.”
In the study, the authors combined chemical records from cave stalagmites with isotopic data from fossil teeth from a pygmy elephant species (Stegodon florensis insularis) that Homo floresiensis hunted.
The results reveal an extensive drying trend beginning around 76,000 years ago, culminating in severe drought between 61,000 and 55,000 years ago, around the time the hominin species disappeared.
Prolonged drought and competition for resources may have driven their departure from Liang Bua and, ultimately, their extinction.
“The ecosystem around Liang Bua became dramatically drier around the time Homo floresiensis vanished,” said University of Wollongong’s Honorary Professor Mike Gagan, the lead author of the study.
“Summer rainfall fell and river-beds became seasonally dry, placing stress on both hobbits and their prey.”
The pygmy elephant population fell steeply around 61,000 years ago, meaning that an important food source for the hobbits was disappearing.
“Surface freshwater, Stegodon and Homo floresiensis all decline at the same time, showing the compounding effects of ecological stress,” said University of Wollongong’s Dr. Gert van den Berg.
“Competition for dwindling water and food probably forced the hobbits to abandon Liang Bua.”
“While Homo floresiensis fossils pre-date the earliest evidence of modern humans on Flores, Homo sapiens were traversing the Indonesian archipelago around the time the hobbits disappeared.”
“It’s possible that as the hobbits moved in search of water and prey, they encountered modern humans,” Professor Gagan said.
“In that sense, climate change may have set the stage for their final disappearance.”
The study was published in the journal Communications Earth & Environment.
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M.K. Gagan et al. 2025. Onset of summer aridification and the decline of Homo floresiensis at Liang Bua 61,000 years ago. Commun Earth Environ 6, 992; doi: 10.1038/s43247-025-02961-3
