A single bird bone from Liang Bua—the Indonesian cave famous for Homo floresiensis, the “hobbit”—has turned out to belong to a new species of giant chicken relative. Researchers named it Megapodius rokusi, an extinct megapode estimated to have weighed about 3.9 kilograms, or 8.6 pounds.
The fossil is only the lower portion of a right tarsometatarsus, a long bone in the lower leg and foot. Yet its size and anatomy were distinctive enough to separate it from every known living and extinct member of the genus Megapodius. It is also the first fossil megapode described from Wallacea, the island region between continental Asia and Australia.
One bone carried an unexpected amount of information
The specimen, cataloged as LB-Av-1542, was excavated at Liang Bua in 2009. It came from sediments dated to roughly 190,000 to 120,000 years ago. The new description was published online in the journal Alcheringa on October 22, 2026.
Researchers compared the fossil with lower-leg bones from living and extinct megapodes. The positions and shapes of its toe joints, along with other features on the preserved bone, did not match another species. Its dimensions also placed it beyond all other known members of Megapodius.
Body mass cannot be placed on a prehistoric scale, of course. The team estimated 3.9 kilograms from the relationship between leg-bone measurements and body size in related birds. That makes M. rokusi comparable to large extinct megapodes from Australia and several times heavier than the orange-footed megapode that lives on Flores today.
Megapodes hatch eggs without sitting on them
Megapodes are sometimes called incubator birds or mound-builders. Instead of warming eggs with their bodies, members of the family bury them and use environmental heat. Depending on the species, that warmth can come from sun-heated sand, volcanic ground, or decaying vegetation piled into a nest mound.
Their chicks emerge unusually independent. A newly hatched megapode can dig its way out and begin moving without the long period of parental feeding familiar from many other birds. It is a life strategy that sounds as if someone tried to design a bird using survival-game settings.
Not every species in the group builds the same kind of mound or burrow, so the fossil does not reveal exactly how M. rokusi incubated its eggs. Its family ties establish the broader reproductive strategy; the details remain unavailable in a single leg bone.
The hobbit cave was a crowded biological archive
Liang Bua is best known as the discovery site of Homo floresiensis, the small-bodied human relative formally described in 2004. The cave’s deposits also preserve dwarf Stegodon, Komodo dragons, a giant stork, rats, bats, and more than 40 bird taxa.
That makes the new megapode part of a much larger picture of Flores during the Pleistocene. Island ecosystems repeatedly produce strange shifts in body size: large animals may become smaller, while smaller lineages can grow into giants when competition and predators differ from those on a continent.
The fossil’s presence in the same cave as the hobbit does not prove the bird and Homo floresiensis met, hunted one another, or shared a particular meal. The bone comes from a specific dated layer, and the paper does not establish a direct interaction. “Same cave” is the accurate connection; “prehistoric roommates” would be doing far too much work.
The name honors a scientist behind the hobbit discovery
The species name rokusi honors the late Indonesian zooarchaeologist Rokus Due Awe. The researchers credit him with a major role in studying the cave’s animal remains. He was also the first person to correctly recognize that unusual bones and teeth from Liang Bua belonged to the hominin later named Homo floresiensis.
Current reporting on the study notes that he also recognized the newly described specimen as a bird bone. Naming the first fossil megapode known from Wallacea after him ties the discovery to the careful identification work that made Liang Bua scientifically famous in the first place.
What scientists still cannot know
The discovery leaves several large blanks. No shoulder or wing bones have been found, so researchers cannot tell whether M. rokusi could fly. The team does not know when the species disappeared or why it went extinct. A reconstruction published with the paper uses the general Megapodius body plan to show the estimated size difference, not a complete set of fossil evidence for the bird’s feathers, colors, or silhouette.
More bones could test the mass estimate, reveal its flight ability, and show how the animal fits among its relatives. For now, the honest picture is both smaller and stranger: one partial foot bone identifies the largest known member of its genus and adds an entirely new bird to a cave already famous for rewriting the story of human evolution.
Sources
The primary study is “A new species of megapode from the Pleistocene of Liang Bua, Flores”. Current reporting and figure descriptions are available from Phys.org. The featured-image source and licensing record are preserved on Wikimedia Commons.
Featured image: Liang Bua cave on Flores, Indonesia, the site where the fossil was excavated. Photo by Rosino, via Wikimedia Commons, licensed under CC BY-SA 2.0. The image is used unchanged; no endorsement is implied.
