[Paper] Evolutionary history and adaptation of a human pygmy population of Flores Island, Indonesia

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A new paper in Science examining the genomes of modern pygmies in the island of Flores found similarities with Neanderthal and Denisovan  sequences, but nothing else unexpected, which would suggest that the modern pygmies have no genetic link with the island’s most famous pygmy, Homo floresiensis.

Evolutionary history and adaptation of a human pygmy population of Flores Island, Indonesia
Tucci et al.
Science, doi: 10.1126/science.aar8486

Flores Island, Indonesia, was inhabited by the small-bodied hominin species Homo floresiensis, which has an unknown evolutionary relationship to modern humans. This island is also home to an extant human pygmy population. Here we describe genome-scale single-nucleotide polymorphism data and whole-genome sequences from a contemporary human pygmy population living on Flores near the cave where H. floresiensis was found. The genomes of Flores pygmies reveal a complex history of admixture with Denisovans and Neanderthals but no evidence for gene flow with other archaic hominins. Modern individuals bear the signatures of recent positive selection encompassing the FADS (fatty acid desaturase) gene cluster, likely related to diet, and polygenic selection acting on standing variation that contributed to their short-stature phenotype. Thus, multiple independent instances of hominin insular dwarfism occurred on Flores.

Source: Evolutionary history and adaptation of a human pygmy population of Flores Island, Indonesia | Science, 03 August 2018

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UO archaeologists cast doubt on controversial ‘hobbit’ theory

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I remember posting about the Palau hobbits 10 (!) years ago when the story came out, and how there was a lot of dispute about it (see here, here and here). Now a new paper in Antiquity disproves this claim of island dwarfism leading to a ‘hobbit’ population living in Palau.

Remains found on a Pacific island were just small humans, Scott Fitzpatrick contends

Source: UO archaeologists cast doubt on controversial ‘hobbit’ theory

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Possible Hobbit ancestors found in Flores, dating 700,000 years

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Mata Menge site. Source: Nature via ABC News 20160609

A new paper out in Nature last month detail the find of tiny hominid bones in Flores, home of H. floresiensis. The fossils from Mata Menge date to 700,000 years old, and suggest that the hobbit had been older and had a longer history on the island than previously thought.

Homo floresiensis-like fossils from the early Middle Pleistocene of Flores
Nature, 09 June 2006
doi:10.1038/nature17999

‘Hobbit’ relatives found after ten-year hunt
Nature, 08 June 2016

Homo floresiensis has been uncovered at the 700,000 year old site of Mata Menge, Flores, Indonesia
Human Evolution @ UCK, 08 June 2016

Flores fossil discovery provides clues to ‘hobbit’ ancestors
The Guardian, 08 June 2016

Flores fossil discovery gives new clue to ‘hobbit’ relatives
AFP, via Economic Times, 09 June 2016

Hobbit discovery: Hopes 700,000-year-old find could shed new light on evolution
ABC News, 09 June 2016

New fossils shed light on the origin of ‘hobbits’
Griffith University, via Popular Archaeology, 09 June 2016

Australian-led team unlocked new questions about human evolution and the history of the`Hobbit’
News.com.au, 10 June 2016

The evolutionary origin of Homo floresiensis, a diminutive hominin species previously known only by skeletal remains from Liang Bua in western Flores, Indonesia, has been intensively debated. It is a matter of controversy whether this primitive form, dated to the Late Pleistocene, evolved from early Asian Homo erectus and represents a unique and striking case of evolutionary reversal in hominin body and brain size within an insular environment1–4. The alternative hypothesis is that H. floresiensis derived from an older, smaller-brained member of our genus, such as Homo habilis, or perhaps even late Australopithecus, signalling a hitherto undocumented dispersal of hominins from Africa into eastern Asia by two million years ago (2 Ma)5,6. Here we describe hominin fossils excavated in 2014 from an early Middle Pleistocene site (Mata Menge) in the So’a Basin of central Flores. These specimens comprise a mandible fragment and six isolated teeth belonging to at least three small-jawed and small-toothed individuals. Dating to ~0.7 Ma, these fossils now constitute the oldest hominin remains from Flores7. The Mata Menge mandible and teeth are similar in dimensions and morphological characteristics to those of H. floresiensis from Liang Bua. The exception is the mandibular first molar, which retains a more primitive condition. Notably, the Mata Menge mandible and molar are even smaller in size than those of the two existing H. floresiensis individuals from Liang Bua. The Mata Menge fossils are derived compared with Australopithecus and H. habilis, and so tend to support the view that H. floresiensis is a dwarfed descendent of early Asian H. erectus. Our findings suggest that hominins on Flores had acquired extremely small body size and other morphological traits specific to H. floresiensis at an unexpectedly early time.

Article link here.

Hobbits older than expected

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A new paper in Nature has revised the dates of the Hobbit, once thought to be 12,000 years old, to be an older 50,000 years old. This period roughly coincides with the time modern humans started appearing in the region, and while it’s tempting to think the two events are related it’s still too early to tell.

Revised stratigraphy and chronology for Homo floresiensis at Liang Bua in Indonesia
Sutikna et al.
Nature, doi:10.1038/nature17179

Suspicious: Hobbits Vanish When Modern Humans Appear
Discovery News, 30 March 2016

Indonesian ‘Hobbits’ may have died out sooner than thought
Griffith University, 30 March 2016

A decade ago, researchers reported that evolutionary cousins of modern humans, nicknamed hobbits, lived until fairly recently in an Indonesian cave
AP, via US News, 30 March 2016

The ‘hobbit’ was a separate species of human, new dating reveals
Science, 30 March 2016

Scientists: New evidence Indonesian ‘Hobbits’ disappeared 50K years ago
KVAL, 31 March 2016

Diminutive ‘Hobbit’ people vanished earlier than previously known, scientists say
Reuters, via Malay Mail, 31 May 2016

Homo Floresiensis: A Profile Of The Extinct ‘Hobbits’ Of Indonesia
Tech Times, 31 May 2016

New Homo Floresiensis Dates May Quash Cryptozoology Theories About ‘Hobbits’
Forbes, 31 May 2016

The ‘hobbits’ were extinct much earlier than first thought
The Conversation AU, 31 March 2016

‘Hobbits’ extinct much earlier than first thought
Australian Geographic, 31 March 2016

Forget Tolkien, the scientific tale of real-life “hobbits” is even more complex
Ars Technica, 01 April 2016

‘Hobbit’ people were no match for the unstoppable juggernaut of modern man
Tech Insider, 04 April 2016

The Hobbit gets a little older, and science a little wiser
The Conversation AU, 05 April 2016

Homo floresiensis, a primitive hominin species discovered in Late Pleistocene sediments at Liang Bua (Flores, Indonesia), has generated wide interest and scientific debate. A major reason this taxon is controversial is because the H. floresiensis-bearing deposits, which include associated stone artefacts and remains of other extinct endemic fauna, were dated to between about 95 and 12 thousand calendar years (kyr) ago. These ages suggested that H. floresiensis survived until long after modern humans reached Australia by ~50 kyr ago. Here we report new stratigraphic and chronological evidence from Liang Bua that does not support the ages inferred previously for the H. floresiensis holotype (LB1), ~18 thousand calibrated radiocarbon years before present (kyr cal. BP), or the time of last appearance of this species (about 17 or 13–11 kyr cal. BP). Instead, the skeletal remains of H. floresiensis and the deposits containing them are dated to between about 100 and 60 kyr ago, whereas stone artefacts attributable to this species range from about 190 to 50 kyr in age. Whether H. floresiensis survived after 50 kyr ago—potentially encountering modern humans on Flores or other hominins dispersing through southeast Asia, such as Denisovans12, 13—is an open question.

Nature paper here.

Teeth study of H. floresiensis unlike any other, suggests new species

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A new study on the tooth morphology of Homo floresiensis suggests that they may be not be a group deformed modern humans, and may also support the theory that the hobbits were derived from Homo erectus undergoing island dwarfism.

Teeth of Homo floresiensis. Source: PLOS One DOI: 10.1371/journal.pone.0141614

Teeth of Homo floresiensis. Source: PLOS One DOI: 10.1371/journal.pone.0141614

Hobbits Were a Separate Species, Ancient Chompers Show
Live Science, 18 November 2015

Fossils Reveal That Ancient Hobbits Were A Separate Species
IFL Science, 19 November 2015

“Hobbit” Teeth Analyzed
Archaeology, 20 November 015

Unique Dental Morphology of Homo floresiensis and Its Evolutionary Implications
Kaifu et al, PLOS One
DOI: 10.1371/journal.pone.0141614

Homo floresiensis is an extinct, diminutive hominin species discovered in the Late Pleistocene deposits of Liang Bua cave, Flores, eastern Indonesia. The nature and evolutionary origins of H. floresiensis’ unique physical characters have been intensively debated. Based on extensive comparisons using linear metric analyses, crown contour analyses, and other trait-by-trait morphological comparisons, we report here that the dental remains from multiple individuals indicate that H. floresiensis had primitive canine-premolar and advanced molar morphologies, a combination of dental traits unknown in any other hominin species. The primitive aspects are comparable to H. erectus from the Early Pleistocene, whereas some of the molar morphologies are more progressive even compared to those of modern humans. This evidence contradicts the earlier claim of an entirely modern human-like dental morphology of H. floresiensis, while at the same time does not support the hypothesis that H. floresiensis originated from a much older H. habilis or Australopithecus-like small-brained hominin species currently unknown in the Asian fossil record. These results are however consistent with the alternative hypothesis that H. floresiensis derived from an earlier Asian Homo erectus population and experienced substantial body and brain size dwarfism in an isolated insular setting. The dentition of H. floresiensis is not a simple, scaled-down version of earlier hominins.

The full paper can be downloaded on PLOS One.

Liang Bua popular with tourists seeking the ‘hobbit’

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Liang Bua. Source: Pos Kupang 20150510

The Liang Bua site in Flores has seen a jump in popularity by foreign tourists due to the discovery of Homo floresiensis, but the site itself is not set up to receive tourists.

Liang Bua. Source: Pos Kupang 20150510

Liang Bua. Source: Pos Kupang 20150510

Turis Asing Dominasi ke Liangbua
Pos Kupang, 10 May 2015
Article is in Bahasa Indonesia

Regency to boost hobbit tourism
Jakarta Post, 11 May 2015

Situs Liang Bua, lokasi ditemukankan tulang manusia purba Flores (Homo Floresiensis) oleh tim penggali dari Arkelogi Indonesia dan asing tanggal 6 September 2003 menyedot perhatian wisatawan asing dari Eropa.

Kunjungan turis asing dari Benua Eropa dari kaum peneliti atau peminat khusus mendominasi kedatangan ke situs yang mendadak terkenal pasca penemuan manusia purba Flores.

Full story here.

New paper argues against claims of Hobbit Down Syndrome theory

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Skull of LB1. Source: The Conversation 20150210

A new paper in PNAS tears down the arguments made last year in the same journal about the Hobbit being a human with Down Syndrome. The arguments centre around the attributes of LB1 and LB6’s chins. The Conversation piece by the same authors breaks it down nicely.

Skull of LB1. Source: The Conversation 20150210

Skull of LB1. Source: The Conversation 20150210

Down syndrome theory on Hobbit species doesn’t hold to scrutiny
The Conversation, 10 February 2015

Mandibular evidence supports Homo floresiensis as a distinct species
Proceedings of the National Academy of Science, doi: 10.1073/pnas.1418997112

Henneberg et al. (1) and Eckhardt et al. (2) present another pathology-based alternative to the hypothesis that the “hobbit” fossils from Liang Bua, Indonesia, represent a distinct hominin species, Homo floresiensis. They contend that the Liang Bua specimens are the remains of small-bodied humans and that the noteworthy features of the most complete specimen, LB1, are a consequence of Down syndrome (DS). Here, we show that the available mandibular evidence does not support these claims.

Absence of chins in the two mandibles recovered at Liang Bua, LB1 and LB6, is a key issue (1, 3). That these specimens lack chins has been argued to preclude their attribution to Homo sapiens, because a chin is widely accepted to be a defining characteristic of our species (3). Henneberg et al. reject this argument on the grounds that a chin is often absent in living Australo-Melanesians. However, the evidence they present does not support their assertion regarding Australo-Melanesian mandibular morphology. One of two studies they cite has not been peer reviewed (the publication is just a conference abstract), whereas the other one has been severely criticized (4). Henneberg et al. also imply that a mandible from Roonka, Australia, supports their claim, but a CT scan of this specimen shows that it has a positive chin (Fig. 1). Thus, there is no reason to believe that living Australo-Melanesians often lack chins and therefore no reason to overturn Brown and Tomoko’s (3) assessment that the absence of chins in LB1 and LB6 precludes their attribution to H. sapiens.

The link to the paper here.

Criticisms over the hobbit-Down Syndrome paper

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There seems to be more than meets the eye with the latest paper in PNAS on the ‘hobbit’ as a person with Down syndrome. The Guardian has a story on the criticism and reactions to this paper.

Homo floresiensis

Homo floresiensis: scientists clash over claims ‘hobbit man’ was modern human with Down’s syndrome
The Guardian, 17 August 2014
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