Homo floresiensis A recent study indicates that Liang Bua, the cave where this diminutive hominin species resided for approximately 140,000 years, was deserted during a significant drought between 61,000 and 55,000 years ago.
Reconstruction of Homo floresiensis. Image credit: Elizabeth Danes.
Homo floresiensis was first identified in 2003 in Liang Bua, Flores Island, Indonesia.
This species, often referred to as hobbits due to their small size, challenged prevailing theories regarding human evolution.
It vanished from the fossil record around 50,000 years ago, but the reasons for its disappearance are still unclear.
“In 2003, excavations in the Liangbua rock trench unveiled the skeletons of a previously unknown small hominid species, Homo floresiensis,” stated Emeritus Professor Mike Gagan and colleagues from the University of Wollongong.
“Originally, the period of occupation was estimated to be between 95,000 and 12,000 years ago, suggesting the possibility of interaction with early modern humans (Homo sapiens), who inhabited islands in Southeast Asia and were contributing to species extinctions.”
“However, following a revision of the stratigraphy and chronology at this site, all Homo floresiensis human bones are now believed to be approximately 100,000 to 60,000 years old.”
“Associated stone artifacts and megafaunal assemblages typically suggest that Homo floresiensis went extinct around 50,000 years ago.”
“The revised timeline indicates they disappeared from the record around 46,000 years ago, coinciding with the arrival of modern humans at Liang Bua, and there was a significant shift in the types of materials used for making stone tools.”
In the study, the authors integrated chemical records from cave stalagmites with isotope data from the fossilized teeth of a pygmy elephant species, Stegodon florensis insularis, which Homo floresiensis hunted.
The findings reveal a large-scale drying trend that commenced around 76,000 years ago and peaked in severe droughts between 61,000 and 55,000 years ago, near the time when the species went extinct.
Prolonged drought and heightened competition for resources may have led to their abandonment of Liang Bua and, ultimately, their extinction.
“At that time, the ecosystem surrounding Liang Bua experienced significant drying. Homo floresiensis vanished,” remarked the lead author of the study, Emeritus Professor Mike Gagan from the University of Wollongong.
“The summer rains caused the riverbed to become dry seasonally, placing stress on both the hobbits and their prey.”
The population of pygmy elephants saw a drastic decline around 61,000 years ago, signaling the loss of a crucial food source for the hobbits.
“Surface freshwater, along with Stegodon and Homo floresiensis, all diminished simultaneously, showcasing the compounded effects of ecological stress,” stated Dr. Gerd van den Bergh from the University of Wollongong.
“Competition for the scarce water and food likely forced the hobbits to vacate Liang Bua.”
“Meanwhile, the fossils of Homo floresiensis predate the earliest evidence of modern humans on Flores, Homo sapiens, who were traversing the Indonesian archipelago when the hobbits went extinct.”
“It’s possible that the hobbits encountered modern humans while migrating in search of water and food,” Professor Gagan noted.
“In that context, climate change may have set the stage for their eventual extinction.”
The study was published in the journal Communication Earth and Environment.
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MK Gagan et al. 2025. The onset of summer dryness and forest decline of Homo floresiensis at Liang Bua 61,000 years ago. Communication Earth and Environment 6,992; doi: 10.1038/s43247-025-02961-3
Source: www.sci.news
