Liang Bua

Liang Bua
Liang Bua
	Cave where the remains of Homo floresiensis were found
Location	Flores, East Nusa Tenggara, Indonesia
Length	50 meters
Discovery	1950s
Geology	Limestone
Entrances	1

Last updated January 05, 2024

Liang Bua is a limestone cave on the island of Flores, Indonesia, slightly north of the town of Ruteng in Manggarai Regency, East Nusa Tenggara. The cave demonstrated archaeological and paleontological potential in the 1950s and 1960s as described by the Dutch missionary and archaeologist Theodor L. Verhoeven.^[1]

In September 2003, an Indonesian field team and its coordinator of the excavation team, Thomas Sutikna, uncovered the first indications of a skull. Initially, the archeologists only analyzed the top of the cranium and due to the small size believed that the skull belonged to a small child. However, Sutikna and his colleagues soon discovered that its teeth were permanent and mature, revealing that it actually belonged to a fully grown adult.^[2] After a few weeks, the team had discovered most of this particular hominid's skeleton and later was coded LB1, LB2, etc., after the name of the cave.^[2] This skeleton later became the holotype specimen of Homo floresiensis, also known as the "hobbit."^[3] Despite the small stature and brain size, Homo floresiensis was capable of using stone tools, hunting animals such as small elephants and rodents, and dealing with many predators such as large komodo dragons.^[4] As of 2022, excavations are still being conducted and additional findings such as teeth are being discovered and analyzed.

There has been much debate whether the skeletal remains are actually Homo floresiensis due to the small nature of these specimens. As of 2022, further research and studies are still being conducted to confirm whether these discoveries are Homo floresiensis.

History of discoveries

Theodor L. Verhoeven, a Dutch missionary and archaeologist, was living in Flores in the 1950s and 60s. Verhoeven had been a keen student of archeology at the University of Utrecht. During this time, he worked at a Catholic seminary and in his free time would explore many archeological sites and perform many excavations in Flores. He discovered stone tools and suspected that Homo erectus from Java had made these.^[5] However, Verhoeven's work was not acknowledged by many paleoanthropologists at this time. After 30 years, an Indonesian-Dutch excavation team discovered new evidence that suggest that Verhoeven's predictions were correct.^[6]

In 2001, an Indonesian-Australian team began excavations in Liang Bua. Their goal was to excavate deeper into the cave hoping to see if modern or pre-modern humans were using Liang Bua.^[2] They were led by Indonesian field coordinator, Thomas Sutikna.^[2]

In 2003, Benyamin Tarus, a locally hired worker, was excavating a 2 by 2 meter square and found the first indication of a skull at a depth of 6 meters.^[2] At that point, many archeologists stepped in to help carefully remove sediment from the top of the skull. Rokus Due Awe, an Indonesian faunal expert, was called in to help inspect the excavated top portion of the skull.^[7] By looking at just the top of the skull, Awe believed it belonged to a small child due to the small size of the cranium. However, after several days of excavating, more of the cranium and mandible became exposed. This allowed Awe to further analyze the age and condition of the skull. They discovered that its teeth were permanent, revealing that this skull actually belonged to an adult.^[2] The team had discovered most of this particular hominid's skeleton and many stone tools that they may have created and used. They were later coded LB1, LB2, etc., after the name of the cave.

Peter Brown, an expert on cranial, mandibular, and dental anatomy of early and modern humans, was asked to help identify and analyze this new discovery. The skeletal evidence indicates that the adults of these species weighed around 66 to 86 pounds, had an average height of 106 cm (3'6") tall, and had very small brains (400 ml).^[8] Brown concluded that the proportions between the humerus and femur were very similar to the proportions in Australopithecus and Homo habilis.^[8] The characteristics of this skeleton appeared more similar to those of early hominins like Australopithecus afarensis than to those of modern humans.^[2] This skeleton later became the holotype specimen of Homo floresiensis.

The key specimens that many researchers focus on are LB1 and LB6. LB1 was discovered unfossilized in September 2003 and consisted of an almost complete skull and partial skeleton. Scientists assume that LB1 was a female of about 30 years old, about one metre tall, had a brain volume of about 380 to 420 ml, and weighed approximately 55 pounds.^[9] On the other hand, LB6 consisted of a partial skeleton that appeared shorter than LB1 and its jaw was significantly different as it was more V- shaped. Scientists assume that LB6 was a child and was approximately five years old.^[9]

In 2004 Kira Westaway, a paleoanthropologist at the University of Wollongong, analyzed a thick blanket of sediment that the fossils were found in and discovered that these bones ranged from 18,000 to 38,000 years old.^[10] This suggests that these species at Liang Bua were alive during modern times and could have possibly shared this island with modern humans for approximately 30,000 years.^[10]

Further research and findings

In 2010 and 2011, archaeologists discovered two hominin teeth in the cave that did not come from Homo floresiensis. According to Sutikna, the teeth date to around 46,000 BP and Sutkina and his team speculate that the teeth are likely to have come from Homo sapiens .^[11] Sutikna proposed that Homo sapiens could have coexisted with the "hobbits" for thousands of years and he also proposed that Homo sapiens could have led to the extinction of Homo floresiensis. However, there is no evidence to indicate that and as of 2016 research was still being conducted to prove his hypothesis.^[11]

In 2013, a 3D model of the cave created via laser scanning was made available online by the Smithsonian Institution.^[12]

In 2016, scientists discovered a lower jaw and teeth from at least one adult and potentially two children in Mata Menge, about 70 km east of Liang Bua. These findings are dated to about 700,000 years BP and could possibly be an early form of Homo floresiensis.^[9] Additionally in 2016, Sutikna, Smithsonian researcher Matt Tocheri, and other researchers announced that they concluded that the skeletal remains at Liang Bua became extinct around 50,000 years ago, much earlier than many researchers had originally thought.^[13] In addition, archaeologists discovered stone tools in the cave that were used from 190,000 to 50,000 years BP.^[2]

Disagreement

There is continuing disagreement among scientists as to whether the discoveries represent a new and distinct hominid species.^[14] The disagreement stems from the abnormal size of the skeletal remains found in Liang Bua. At the time, many of the skeletal remains found before were significantly larger. As a result, many researchers doubted the skeletal remains found were actually a new hominid species.

There are many different theories that researchers have created when trying to explain that the skeletal remains found do not represent a new hominid species. Many believe that it is more likely that the bones of the most complete individual found in Liang Bua (individual LB1) are those of a local person who possibly had a medical condition or a developmental disorder (perhaps Down syndrome) rather than a unique species of Homo that lived in Flores.^[15] LB1 had a small cranial volume, reported as approximately only 380 ml, about one third less than the average modern human. LB1 has very distinct short thighbones, which is a characteristic seen in those with Down syndrome.^[16] Robert B Eckhardt, professor of developmental genetics and evolution at Penn State, and his team suggest that the small cranial volume and short thighbones are consistent with a Down syndrome diagnosis. These sizes fall within those for a modern human with Down syndrome from the same geographic region.^[16] These characteristics are only present in LB1 and not in the other skeletal remains found in Liang Bua. Dr. Eckhardt believes that this is only further evidence that LB1 had Down syndrome due to its abnormality.

Another theory that researchers in 2011 suggested was that the species found in Liang Bua actually had microcephaly,^[17] a condition where a baby's head is much smaller than expected. To test this, Ralph Holloway, an anthropologist at Columbia University, used MRI. Holloway and his team discovered that the skeletal remains found in Liang Bua did not fall within the range for microcephalic humans.^[18] They concluded that the skeletal remains found in Liang Bua most likely did not have microcephaly and the findings are most likely a new and distinct hominid species. Holloway believed the reason for their small brain was that this was organized differently and thus only needing a smaller volume. However, many researchers disagree with Holloway's conclusion believing that there were many confounding variables that were not taken into account when testing for microcephaly in these fossils.^[19] Dean Falk, an anthropologist at Florida State University in Tallahassee, critiques Holloway's conclusion believing that Holloway's endocast (a 3D representation of the space within a cavity) was mis-shaped by the cracks and chips present in the ancient fossil head. Falk previously conducted a computed tomography (CT) scan of the Homofloresiensis skull and found that the skeletal evidence found is likely to be a separate species.^[20]

One theory during this time was that Homo erectus moved to Flores and over time their brains began to decrease in size due to island dwarfism, an evolutionary phenomenon whereby body size decreases significantly over time.^[21] However, opponents of this theory argue that Homo erectus's brain would not be able to shrink in relation to its body.^[22]

Even so, there are still many researchers that argue that the discoveries in Liang Bua represent a new distinct species that lived in relatively modern times. Sutikna, Smithsonian researcher Matt Tocheri, and other researchers announced that they conclude that the geological dating at Liang Bua became extinct around 50,000 years ago, which would be 10,000 years before Homo sapiens arrived in the region.^[13]

Palaeofauna

After^[23]^[24]

Homo floresiensis
Stegodon florensis insularis , dwarfed stegodontid proboscidean
Papagomys theodorverhoeveni , giant rat
Papagomys armandvillei , giant rat
Spelaeomys florensis, giant rat
Hooijeromysnusatenggara medium-sized rat
Komodomysrintjanus small rat
Rattus exulans (Polynesian rat)
Rattus hainaldi small rat
Varanus komodoensis , (Komodo dragon)
Varanus hooijeri frugivorous monitor lizard
Leptoptilos robustus , giant stork
Trigonoceps sp., vulture

Related Research Articles

Flores is one of the Lesser Sunda Islands, a group of islands in the eastern half of Indonesia. Including Komodo Island off its west coast, the land area is 15,530.58 km², and the population was 1,878,875 in the 2020 Census ; the official estimate as at mid 2022 was 1,919,395. The largest towns are Maumere and Ende. The name Flores is of Portuguese origin, meaning "Flowers".

Homininae, also called "African hominids" or "African apes", is a subfamily of Hominidae. It includes two tribes, with their extant as well as extinct species: 1) the tribe Hominini ―and 2) the tribe Gorillini (gorillas). Alternatively, the genus Pan is sometimes considered to belong to its own third tribe, Panini. Homininae comprises all hominids that arose after orangutans split from the line of great apes. The Homininae cladogram has three main branches, which lead to gorillas, and to humans and chimpanzees via the tribe Hominini and subtribes Hominina and Panina. There are two living species of Panina and two living species of gorillas, but only one extant human species. Traces of extinct Homo species, including Homo floresiensis have been found with dates as recent as 40,000 years ago. Organisms in this subfamily are described as hominine or hominines.

Homo floresiensis( also known as "Flores Man") is an extinct species of small archaic human that inhabited the island of Flores, Indonesia, until the arrival of modern humans about 50,000 years ago.

The Flores giant rat is a rodent of the family Muridae that occurs on the island of Flores in Indonesia. It has been recorded in Rutong Protection Forest. The species is found in primary, secondary and disturbed forest over a wide range of elevations. Its head and body length is 41–45 cm (16–17.5 in) and its tail length is 33–70 cm (13–27.5 in). These dimensions are about twice as large as those of a typical brown rat, which suggests about eight times the body mass.

Papagomys is a genus of very large rats in the tribe Rattini of the subfamily Murinae, with body masses of 600–2,500 grams (1.3–5.5 lb). It contains two species, which are known only from the Indonesian island of Flores:

<span class="mw-page-title-main">Verhoeven's giant rat</span> Species of rodent

Verhoeven's giant rat is an extinct rat of subfamily Murinae that lived on Flores in Indonesia. It was judged to be extinct in 1996. However, experts believe that it died out before 1500 AD. The species is known only from several subfossil fragments. It was named after Dutch priest Theodor Verhoeven. A 1974 report of a recent specimen has been judged to represent P. armandvillei instead. It was somewhat smaller than P. armandivillei, with an estimated body mass of around 0.6–1.6 kilograms (1.3–3.5 lb). It is assumed to have been terrestrial, and to have been an omnivore, consuming fruit and invertebrates.

Paulamys is a genus of rat. Its only known member is Paulamys naso a species endemic to Flores Island, Indonesia. Paulamys naso was first described from subfossil fragments collected in the 1950s by Theodor Verhoeven and was named Floresomys naso by Guy Musser in 1981. Since Floresomys was preoccupied, Musser changed the name to Paulamys, after Verhoeven's life partner Paula Hamerlinck. A living specimen was reported from the montane forest of western Flores in 1989. It is recorded as common between 1,000 and 2,000 m above sea level on the volcanic mountain Gunung Ranakah, but is believed to be threatened by habitat destruction. It is thought to prefer closed habitats.

Spelaeomys florensis, is an extinct species of rat that was formerly endemic to the island of Flores, Indonesia. MacPhee and Flemming assessed this species to be extinct in 1996, but believed it probably died out before 1500. This specimen is only known from subfossil remains, including at Liang Bua cave. It is the only member of the genus Spelaeomys. It was large sized species with a body mass of around 0.6–1.6 kilograms (1.3–3.5 lb). It is suggested to have been arboreal animal that lived in closed forests, and to have been herbivorous, consuming leaves and flowers.

Post-canine megadontia is a relative enlargement of the molars and premolars compared to the size of the incisors and canines. This phenomenon is seen in some early hominid ancestors such as Paranthropus aethiopicus.

Dean Falk is an American academic neuroanthropologist who specializes in the evolution of the brain and cognition in higher primates. She is the Hale G. Smith Professor of Anthropology and a Distinguished Research Professor at Florida State University.

Theodorus (Theo) Lambertus Verhoeven, SVD, was a Dutch missionary and archaeologist who has become famous by his discovery of stone tools on the Indonesian island of Flores, in association with the c. 800,000-year-old fossils of stegodontids, or dwarf elephants, from which he concluded that islands in Wallacea had been reached by Homo erectus before modern humans appeared there.

The Komodo rat is a species of rodent in the family Muridae endemic to the surrounding islands of Flores in Indonesia, and formerly Flores itself. Its natural habitat is subtropical or tropical dry forests.It is threatened by habitat loss. It is thought to prefer open habitats. It has a body mass of around 100–200 grams (0.22–0.44 lb).

William L. Jungers was an American anthropologist, Distinguished Teaching Professor and the Chair of the Department of Anatomical Sciences at State University of New York at Stony Brook on Long Island, New York. He is best known for his work on the biomechanics of bipedal locomotion in hominids such as the 3.4-million-year-old Lucy, and the 6.1- to 5.8-million-year-old Millennium Man Orrorin tugenensis. He devoted much of his career to the study of the lemurs of Madagascar, especially giant extinct subfossil forms such as Megaladapis. More recently, Jungers has been a subject of media attention due to his analysis of the remains of Homo floresiensis, which he believed to be legitimate members of a newly discovered species based on remains of the shoulder, the wrist, and the feet.

Prehistoric Indonesia is a prehistoric period in the Indonesian archipelago that spanned from the Pleistocene period to about the 4th century CE when the Kutai people produced the earliest known stone inscriptions in Indonesia. Unlike the clear distinction between prehistoric and historical periods in Europe and the Middle East, the division is muddled in Indonesia. This is mostly because Indonesia's geographical conditions as a vast archipelago caused some parts — especially the interiors of distant islands — to be virtually isolated from the rest of the world. West Java and coastal Eastern Borneo, for example, began their historical periods in the early 4th century, but megalithic culture still flourished and script was unknown in the rest of Indonesia, including in Nias and Toraja. The Papuans on the Indonesian part of New Guinea island lived virtually in the Stone Age until their first contacts with modern world in the early 20th century. Even today living megalithic traditions still can be found on the island of Sumba and Nias.

Leptoptilos robustus is an extinct species of large-bodied stork belonging to the genus Leptoptilos that lived on the island of Flores in Indonesia during the Pleistocene epoch. It stood at about 1.8 metres (5.9 ft) tall and weighed up to an estimated 16 kilograms (35 lb). The majority of the discoveries are concentrated in Liang Bua cave located slightly north of Ruteng in the East Nusa Tenggara province.

Professor Michael John Morwood was a New Zealand archaeologist best known for discovering Homo floresiensis. In 2012, he received the Rhys Jones Medal by the Australian Archaeological Association.

Homo naledi is an extinct hominin species discovered in 2013 in the Rising Star Cave system, Gauteng province, South Africa, dating to the Middle Pleistocene 335,000–236,000 years ago. The initial discovery comprises 1,550 specimens of bone, representing 737 different skeletal elements, and at least 15 different individuals. Despite this exceptionally high number of specimens, their classification with other Homo species remains unclear.

Mata Menge is an early Middle Pleistocene paleoanthropological site located in the Ola Bula Formation in the So'a Basin on the island of Flores, Indonesia. Lithic artefacts and hominin remains have been discovered at the site. The level of sophistication of the Mata Menge lithic artefacts is described as being 'simple'.

The region of Southeast Asia is considered a possible place for the evidence of archaic human remains that could be found due to the pathway between Australia and mainland Southeast Asia, where the migration of multiple early humans has occurred out of Africa. One of many pieces of evidence is of the early human found in central Java of Indonesia in the late 19th century by Eugene Dubois, and later in 1937 at Sangiran site by G.H.R. van Koenigswald. These skull and fossil materials are Homo erectus, named Pithecanthropus erectus by Dubois and Meganthropus palaeojavanicus by van Koenigswald. They were dated to c. 1.88 and 1.66 Ma, as suggested by Swisher et al. by analysis of volcanic rocks.

Varanus hooijeri is an extinct species of medium-sized monitor lizard found in Liang Bua on Flores and possibly also Sumba, dating to the Late Pleistocene and Holocene.

References

↑ For Verhoeven, see: Knepper, Gert M. (2019): Floresmens - Het leven van Theo Verhoeven, missionaris en archeoloog, ISBN 978-9-46-3892476 (Boekscout, Soest, Netherlands) (i.e. Verhoeven's biography, in Dutch)
1 2 3 4 5 6 7 8 "'Hobbits' on Flores, Indonesia". The Smithsonian Institution's Human Origins Program. Retrieved 2022-04-28.
↑ Morwood, M. J.; Brown, P.; Jatmiko; Sutikna, T.; Wahyu Saptomo, E.; Westaway, K. E.; Awe Due, Rokus; Roberts, R. G.; Maeda, T.; Wasisto, S.; Djubiantono, T. (October 2005). "Further evidence for small-bodied hominins from the Late Pleistocene of Flores, Indonesia". Nature. 437 (7061): 1012–1017. Bibcode:2005Natur.437.1012M. doi:10.1038/nature04022. ISSN 1476-4687. PMID 16229067. S2CID 4302539.
↑ "Homo floresiensis". The Smithsonian Institution's Human Origins Program. Retrieved 2022-05-18.
↑ "The long search for the earliest inhabitants of Flores". the Guardian. 2016-06-09. Retrieved 2022-05-18.
↑ Collins, Richard (2016-06-27). "New evidence on human evolution on the Indonesian island of Flores". Irish Examiner. Retrieved 2022-05-18.
↑ Callaway, Ewen (2014-10-01). "The discovery of Homo floresiensis: Tales of the hobbit". Nature. 514 (7523): 422–426. doi: 10.1038/514422a . ISSN 1476-4687. PMID 25341771.
1 2 Brown, Peter; Maeda, Tomoko (2009-11-01). "Liang Bua Homo floresiensis mandibles and mandibular teeth: a contribution to the comparative morphology of a new hominin species". Journal of Human Evolution. Paleoanthropological Research at Liang Bua, Flores, Indonesia. 57 (5): 571–596. doi:10.1016/j.jhevol.2009.06.002. ISSN 0047-2484. PMID 19589559.
1 2 3 "Homo floresiensis". The Australian Museum. Retrieved 2022-05-18.
1 2 "The woman who dates Hobbits and giant apes". cosmosmagazine.com. 2017-10-13. Retrieved 2022-06-02.
1 2 Callaway, Ewen (2016-09-21). "Human remains found in hobbit cave". Nature. doi:10.1038/nature.2016.20656. ISSN 1476-4687. S2CID 89272546.
↑ "Liang Bua | 3D Digitization". 3d.si.edu. Retrieved 2022-05-18.
1 2 "The 'hobbit' was a separate species of human, new dating reveals". www.science.org. Retrieved 2022-05-18.
↑ Roberts, Richard 'Bert'; Sutikna, Thomas. "A decade on and the Hobbit still holds secrets". The Conversation. Retrieved 2022-05-18.
↑ Henneberg, Maciej; Eckhardt, Robert. "'Hobbit' more likely had Down Syndrome than a new species". The Conversation. Retrieved 2022-05-18.
1 2 "Flores bones show features of Down syndrome, not a new 'hobbit' human | Penn State University". www.psu.edu. Retrieved 2022-06-02.
↑ CDC (2020-02-18). "Facts about Microcephaly | Birth Defects | NCBDDD". Centers for Disease Control and Prevention. Retrieved 2022-05-18.
↑ Vannucci, Robert C.; Barron, Todd F.; Holloway, Ralph L. (2011-08-23). "Craniometric ratios of microcephaly and LB1, Homo floresiensis, using MRI and endocasts". Proceedings of the National Academy of Sciences. 108 (34): 14043–14048. doi: 10.1073/pnas.1105585108 . ISSN 0027-8424. PMC 3161571 . PMID 21825126.
↑ Kaplan, Matt (2011-08-08). "'Hobbit' just a deformed human?". Nature. doi: 10.1038/news.2011.466 . ISSN 1476-4687.
↑ Falk, Dean; Hildebolt, Charles; Smith, Kirk; Morwood, M. J.; Sutikna, Thomas; Jatmiko; Saptomo, E. Wayhu; Imhof, Herwig; Seidler, Horst; Prior, Fred (2007-02-13). "Brain shape in human microcephalics and Homo floresiensis". Proceedings of the National Academy of Sciences. 104 (7): 2513–2518. doi: 10.1073/pnas.0609185104 . ISSN 0027-8424. PMC 1892980 . PMID 17277082.
↑ Schrein, Caitlin. "Why Dwarfism?". SAPIENS. Retrieved 2022-05-27.
↑ "Study backs 'hobbit' island dwarfism theory". BBC News. 2013-04-17. Retrieved 2022-05-27.
↑ van den Bergh, Gerrit D.; Alloway, Brent V.; Storey, Michael; Setiawan, Ruly; Yurnaldi, Dida; Kurniawan, Iwan; Moore, Mark W.; Jatmiko; Brumm, Adam; Flude, Stephanie; Sutikna, Thomas; Setiyabudi, Erick; Prasetyo, Unggul W.; Puspaningrum, Mika R.; Yoga, Ifan (October 2022). "An integrative geochronological framework for the Pleistocene So'a basin (Flores, Indonesia), and its implications for faunal turnover and hominin arrival". Quaternary Science Reviews. 294: 107721. Bibcode:2022QSRv..29407721V. doi:10.1016/j.quascirev.2022.107721. hdl: 10072/418777 . S2CID 252290750.
↑ Veatch, E. Grace; Tocheri, Matthew W.; Sutikna, Thomas; McGrath, Kate; Wahyu Saptomo, E.; Jatmiko; Helgen, Kristofer M. (May 2019). "Temporal shifts in the distribution of murine rodent body size classes at Liang Bua (Flores, Indonesia) reveal new insights into the paleoecology of Homo floresiensis and associated fauna". Journal of Human Evolution. 130: 45–60. doi: 10.1016/j.jhevol.2019.02.002 . hdl: 2440/121139 .