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{{italictitle}}
{{italictitle}}{{Taxobox | name=''Homo floresiensis''
| fossil_range = Late [[Pleistocene]]
<!-- Please do not insert a taxobox here; use of a taxobox implies that we consider this a good taxon, which would be taking a position in the debate.-->
| image=Homo floresiensis.jpg
⚫
[[File:Homo floresiensis.jpg|thumb|Reconstruction of a ''Homo floresiensis'' skull, [[American Museum of Natural History]]]]
| image_alt=Skull with associated mandible.
⚫
| image_caption=A cast of a ''Homo floresiensis'' skull, [[American Museum of Natural History]]
| classification_status=disputed
| regnum = [[Animal]]ia
| phylum = [[Chordate|Chordata]]
| classis = [[Mammal]]ia
| ordo = [[Primate]]s
| familia = [[Hominidae]]
| tribus = [[Hominini]]
| genus = ''[[Homo (genus)|Homo]]''
| species = '''''H. floresiensis'''''
| binomial = †''Homo floresiensis''
| binomial_authority = Brown et al., 2004
}}


'''''Homo floresiensis''''' ("'''[[Flores]] Man'''") is a possible species of extinct [[Homo (genus)|human]] discovered in 2003 on the island of Flores in [[Indonesia]]. Partial skeletons of nine individuals have been recovered, including one complete [[cranium]] (skull).<ref name="Brown04">Brown ''et al.'' 2004</ref><ref name = "Morwood05">Morwood, Brown ''et al.'' 2005</ref> These remains have been the subject of intense research to determine whether they represent a [[species]] distinct from modern humans, and the progress of this scientific controversy has been closely followed by the news media at large. This hominid is remarkable for its small body and [[brain]] and for its survival until relatively recent times (possibly as recently as 12,000 years ago).<ref name="Morwood04">Morwood, Soejono ''et al.'' 2004</ref> Recovered alongside the skeletal remains were [[stone tool]]s from [[Horizon (archaeological)|archaeological horizons]] ranging from 94,000 to 13,000 years ago. The remains themselves have been dated to between 38,000 and 13,000 years ago.
'''''Homo floresiensis''''' ("'''[[Flores]] Man'''") is a possible species of extinct [[Homo (genus)|human]] discovered in 2003 on the island of Flores in [[Indonesia]]. Partial skeletons of nine individuals have been recovered, including one complete [[cranium]] (skull).<ref name="Brown04">Brown ''et al.'' 2004</ref><ref name = "Morwood05">Morwood, Brown ''et al.'' 2005</ref> These remains have been the subject of intense research to determine whether they represent a [[species]] distinct from modern humans, and the progress of this scientific controversy has been closely followed by the news media at large. This hominid is remarkable for its small body and [[brain]] and for its survival until relatively recent times (possibly as recently as 12,000 years ago).<ref name="Morwood04">Morwood, Soejono ''et al.'' 2004</ref> Recovered alongside the skeletal remains were [[stone tool]]s from [[Horizon (archaeological)|archaeological horizons]] ranging from 94,000 to 13,000 years ago. The remains themselves have been dated to between 38,000 and 13,000 years ago.

Revision as of 02:24, 6 December 2009

Homo floresiensis
Temporal range: Late Pleistocene
Skull with associated mandible.
A cast of a Homo floresiensis skull, American Museum of Natural History
Scientific classification
(disputed)
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Primates
Family:
Hominidae
Tribe:
Hominini
Genus:
Homo
Species:
H. floresiensis
Binomial name
†Homo floresiensis
Brown et al., 2004

Homo floresiensis ("Flores Man") is a possible species of extinct human discovered in 2003 on the island of Flores in Indonesia. Partial skeletons of nine individuals have been recovered, including one complete cranium (skull).[1][2] These remains have been the subject of intense research to determine whether they represent a species distinct from modern humans, and the progress of this scientific controversy has been closely followed by the news media at large. This hominid is remarkable for its small body and brain and for its survival until relatively recent times (possibly as recently as 12,000 years ago).[3] Recovered alongside the skeletal remains were stone tools from archaeological horizons ranging from 94,000 to 13,000 years ago. The remains themselves have been dated to between 38,000 and 13,000 years ago.

The discoverers (anthropologists Peter Brown, Michael Morwood, and their colleagues) proposed that a variety of features, both primitive and derived, identify these individuals as belonging to a new species, H. floresiensis, within the taxonomic tribe of Hominini. Hominini currently comprises the extant species human (genus Homo), bonobo (genus Pan), and chimpanzee (genus Pan); their ancestors; and the extinct lineages of their common ancestor.[1][3] The discoverers also proposed that H. floresiensis lived contemporaneously with modern humans (Homo sapiens) on Flores.

Doubts that the remains constitute a new species were soon voiced by the Indonesian anthropologist Teuku Jacob, who suggested that the skull of LB1 was a microcephalic modern human. Two studies by paleoneurologist Dean Falk and her colleagues (2005, 2007) dispute the possibility of microcephaly.[4][5][6] Falk et al. (2005) has been refuted by Martin et al. (2006) and Jacob et al. (2006) and defended by Morwood (2005) and Argue, Donlon et al. (2006).

Two orthopedic researches published in 2007 both reported evidence to support the species status for H. floresiensis. A study of three tokens of carpal (wrist) bones concluded there were similarities to the carpal bones of a chimpanzee or an early hominin such as Australopithecus and also differences from the bones of modern humans.[7][8] A study of the bones and joints of the arm, shoulder, and lower limbs also concluded that H. floresiensis was more similar to early humans and apes than modern humans.[9][10] In 2009, the publication of a cladistic analysis[11] and a study of comparative body measurements[12] provided further support for the hypothesis that H. floresiensis and Homo sapiens are separate species.

Critics of the claim for species status continue to suggest alternative explanations. One recent hypothesis is that the individuals were born without a functioning thyroid, resulting from a type of endemic cretinism (myxoedematous, ME).[13]

Discovery

Cave on Flores Island where the specimens were discovered.
Flores Island in Indonesia, shown highlighted in red

The first specimens were discovered by a joint Australian-Indonesian team of paleoanthropologists and archaeologists in 2003 looking for evidence of the original human migration of H. sapiens from Asia to Australia.[1][3] They were not expecting to find a new species, and were surprised at the recovery of a nearly complete skeleton of a hominid they dubbed LB1 from the Liang Bua limestone cave on Flores. Subsequent excavations recovered seven additional skeletons, dating from 38,000 to 13,000 years ago.[2] An arm bone, provisionally assigned to H. floresiensis, is about 74,000 years old. The specimens are not fossilized. They were described by Richard Roberts of the University of Wollongong, Australia as having "the consistency of wet blotting paper"; once exposed, the bones had to be left to dry before they could be dug up.[14]

Researchers hope to find preserved mitochondrial DNA to compare with samples from similarly unfossilised specimens of Homo neanderthalensis and H. sapiens.[14]

Sophisticated stone implements of a size considered appropriate to the 1 m tall human are also widely present in the cave. The implements are at horizons from 95,000 to 13,000 years ago and are associated with a juvenile dwarf elephant of the genus Stegodon (which was widespread throughout Asia during the Quaternary), presumably the prey of LB1.[2] They also shared the island with giant rats, Komodo dragons, and even larger species of lizards.[15] Homo sapiens reached the region by around 45,000 years ago.[16]

Anatomy

The most important and obvious identifying features of H. floresiensis are its small body and small cranial capacity. Brown and Morwood also identified a number of additional, less obvious features that might distinguish LB1 from modern H. sapiens, including the form of the teeth, the absence of a chin, and the unusually low twist in the forearm bones. Each of these putative distinguishing features has been heavily scrutinized by the scientific community, with different research groups reaching differing conclusions as to whether these features support the original designation of a new species,[17] or whether they identify LB1 as a severely pathological H. sapiens.[18] The discovery of additional partial skeletons[2] has verified the existence of some features found in LB1, such as the lack of a chin, but Jacob and other research teams argue that these features do not distinguish LB1 from local H. sapiens morphology.[18] Lyras et al. have asserted, based on 3D-morphometrics, that the skull of LB1 differs significantly from all H. sapiens skulls, including those of small-bodied individuals and microcephalics, and is similar only to the skull of Homo erectus.[19]

Small bodies

The first set of remains to have been found, LB1, has been taken as the type specimen for the proposed species. LB1 is a fairly complete skeleton, including a nearly complete cranium (skull), determined to be a 30-year-old female. LB1 has been nicknamed the Little Lady of Flores or "Flo".[1]

LB1's height has been estimated at about 1.06 m (3 ft 6 in). The height of a second skeleton, LB8 has been estimated at 1.09 m (3 ft 7 in) based on measurements of its tibia.[2] These estimates are outside the range of normal modern human height and considerably shorter than the average adult height of even the smallest modern humans, such as the Pygmies (< 1.5 m, or 4 ft 11 in),[20] Twa, Semang (1.37 m, or 4 ft 6 in for adult women) of Africa,[21] or the Andamanese (1.37 m, or 4 ft 6 in for adult women).[22] Body mass is generally considered more biophysically significant than length,[citation needed] and by that measure, differences are even greater. LB1's body mass has been estimated at 25 kg (55 lb). This is smaller than not only modern H. sapiens, but also than H. erectus, which Brown and colleagues have suggested is the immediate ancestor of H. floresiensis. LB1 and LB8 are also somewhat smaller than the australopithecines, from three million years ago, not previously thought to have expanded beyond Africa. Thus, LB1 and LB8 may be the shortest and smallest members of the extended human family discovered thus far.

Aside from smaller body size, the specimens seem otherwise to resemble H. erectus, a species known to be living in Southeast Asia at times coincident with earlier finds purported to be of H. floresiensis.[2] These observed similarities form the basis for the suggested phylogenetic relationship. Controversially, the same team has reported finding material evidence on Flores (stone tools) of a H. erectus occupation dating back 840,000 years ago, but not remains of H. erectus itself, much less transitional forms.

To explain the small stature of H. floresiensis, Brown et al. have suggested that in the limited food environment on Flores H. erectus underwent strong insular dwarfism,[1] a form of speciation which has also been observed in other species on Flores, including a dwarf elephant, genus Stegodon. This hypothesis has been attacked by Teuku Jacob and colleagues[18] who argue that LB1 is similar to the midget humans who populate the village of Rampasasa on the island of Flores[23], and who point out that size can vary substantially in pygmy populations.

Small brains

Top view of a cast of the LB1 skull

In addition to a small body size, H. floresiensis had a remarkably small brain. The brain of the holotype, LB1 is estimated to have had a volume of 380 cm3 (23 cu in)), placing it at the lower range of chimpanzees or the extinct australopithecines.[1][4] LB1's brain size is half that of its presumed immediate ancestor H. erectus (980 cm3 (60 cu in)).[4] The brain to body mass ratio of LB1 lies between that of H. erectus and the great apes.[24] Insular dwarfism has been posited to explain the brain size reduction.[25]

An indicator of intelligence is the size of region 10 of the dorsomedial prefrontal cortex, which is associated with self-awareness and is about the same size as that of modern humans, despite the much smaller overall size of the brain.[4]

Notwithstanding its small brain, the discoverers have associated H. floresiensis with advanced behaviors. There is evidence of the use of fire for cooking in Liang Bua cave, and evidence of cut marks on the Stegodon bones associated with the finds.[2][3] The species has also been associated with stone tools of the sophisticated Upper Paleolithic tradition typically associated with modern humans, who at 1,310–1,475 cm3 (79.9–90.0 cu in) nearly quadruple the brain volume of H. floresiensis (with body mass increased by a factor of 2.6). Some of these tools were apparently used in the necessarily cooperative hunting of local dwarf Stegodon by this small human species.[2]

Additional features

Additional features used to argue that the finds come from a population of previously unidentified hominids include the absence of a chin, the relatively low twist of the arm bones, and the width of the leg bones relative to their length.[1][2][3] The presence of each of these features has been confirmed by independent investigators[18] but their significance has been disputed.

The forearm and pectoral girdle of H. floresiensis have been examined by Larson et al. (2007).[9] Modern humans have the top of the bone twisted between 145 to 165 degrees, which makes the inner part of the elbow face slightly forward. For LB1, Larson originally measured the twist at only 110 degrees,[26] but later made a new measurement and reported 120 degrees. This could be an advantage when arm-swinging, but it complicates activities associated with modern people, such as tool-making. As for the pectoral girdle of H. floresiensis, they studied a broken clavicle of LB1 and a shoulder blade of LB6. The clavicle was relatively short, which in combination with the shape of the shoulder blade and the low twist of the arm bone resulted in the shoulder being moved slightly forward, as if it was shrugged. Thus H. floresiensis could bend the elbow in the way modern people do and Larson concluded that it may have been able to make tools.

Tocheri et al. (2007) examined three carpal bones believed to belong to LB1. The shapes of these bones were claimed to differ significantly from the bones of the modern human wrist and to resemble the wrist of great African apes or Australopithecus.[7]

The feet of H. floresiensis’ feet were unusually flat and large in comparison with the rest of the body.[27] As a result, when walking, it would have to bend its knees further back than modern people do. This forced the gait to be high stepped and the creature was not able to walk very fast. The toes had an unusual shape and the big toe was very short.[28]

Recent survival

The species is thought to have survived on Flores at least until 12,000 years before present, making it the longest lasting non-modern human, surviving long past the Neanderthals (H. neanderthalensis), which became extinct about 24,000 years ago.[2]

Because of a deep neighboring strait, Flores remained isolated during the Wisconsin glaciation (the most recent glacial period), despite the low sea levels that united much of the rest of Sundaland. This has led the discoverers of H. floresiensis to conclude that the species, or its ancestors, could only have reached the isolated island by water transport, perhaps arriving in bamboo rafts around 100,000 years ago (or, if they are H. erectus, then about 1 million years ago). This idea of H. floresiensis using advanced technology and cooperation on a modern human level has prompted the discoverers to hypothesize that H. floresiensis almost certainly had language.[29] This suggestion has been one of the most controversial of the discoverers' findings.

Local geology suggests that a volcanic eruption on Flores approximately 12,000 years ago was responsible for the demise of H. floresiensis, along with other local fauna, including the dwarf elephant Stegodon.[3] Gregory Forth hypothesized that H. floresiensis may have survived longer in other parts of Flores to become the source of the Ebu Gogo stories told among the local people. The Ebu Gogo are said to have been small, hairy, language-poor cave dwellers on the scale of this species.[30] Believed to be present at the time of the arrival of the first Portuguese ships during the 16th century, these creatures are claimed to have existed as recently as the late 19th century.[31] Gerd van den Bergh, a paleontologist working with the fossils, reported hearing of the Ebu Gogo a decade before the fossil discovery.[32] On the island of Sumatra, there are reports of a 1–1.5 m tall humanoid, the Orang Pendek which might be related to H. floresiensis.[33]

Whether the specimens represent a new species is a controversial issue within the scientific community. Professor Teuku Jacob, chief paleontologist of the Indonesian Gadjah Mada University, and other scientists disagree with the placement of the new finds into a new species of Homo. Instead, Jacob proposed that they were members of "... a sub-species of Homo sapiens classified under the Austrolomelanesid race".[34] He contended that the LB1 find is from a 25–30 year-old omnivorous subspecies of H. sapiens, probably a Pygmy, and that the small skull is due to the genetic disorder microcephaly, which produces a small brain and skull.

Scandal of Jacob's investigation

In early December 2004, Jacob removed most of the remains from Soejono's institution, Jakarta's National Research Centre of Archaeology, for his own research without the permission of the Centre's directors.[35][36][37] Some expressed fears that, like the Dead Sea Scrolls, important scientific evidence would be sequestered by a small group of scientists who neither allowed access by other scientists nor published their own research. Jacob eventually returned the remains with portions severely damaged[38] and missing two leg bones on February 23, 2005[39] to the worldwide consternation of his peers. Reports noted the condition of the returned remains; "[including] long, deep cuts marking the lower edge of the Hobbit's jaw on both sides, said to be caused by a knife used to cut away the rubber mould"; "the chin of a second Hobbit jaw was snapped off and glued back together. Whoever was responsible misaligned the pieces and put them at an incorrect angle"; and, "The pelvis was smashed, destroying details that reveal body shape, gait and evolutionary history"[40] and causing the discovery team leader Morwood to remark "It's sickening, Jacob was greedy and acted totally irresponsibly".[38] Jacob, however, denied any wrongdoing. He stated that such damages occurred during transport from Yogyakarta back to Jakarta[40] despite the physical evidence to the contrary that the jawbone had been broken while making a mold of bones.[38]

In 2005 Indonesian officials forbade access to the cave and thus no other excavations in the place were possible. Some media, such as the BBC, expressed the opinion that the reason for the restriction was to protect Jacob, who was considered "Indonesia's king of palaeoanthropology", from being proven to be wrong. Scientists were allowed to return to the cave in 2007, the same year that Jacob died from liver disease.[40]

Research on the microcephaly argument

Prior to Jacob's removal of the fossils, a CT scan was taken of the skull and a virtual endocast of the skull (i.e., a computer-generated model of the skull's interior) of H. floresiensis was produced and analysed by Dean Falk et al.. This team claimed (Falk et al. (2005)) that the brainpan was not that of a pygmy nor an individual with a malformed skull and brain, supporting the view that it is a new species.[4]

In response, Weber et al. conducted a survey the same year comparing the computer model of LB1's skull with a sample of microcephalic human skulls, concluding that the skull size of LB1 falls in the middle of the size range of the human samples and is not inconsistent with microcephaly.[41][42] The findings of Falk et al. (2005) were disputed next by Martin et al. (2006), who objected to the failure to compare the model of LB1's skull with a typical example of adult microcephaly. Martin and his coauthors concluded that the skull was probably microcephalic, arguing that the brain is far too small to be a separate dwarf species; if it were, the 400-cubic-centimeter brain would indicate a creature only one foot in height, one-third the size of the discovered skeleton.[43] Shortly thereafter, a group of scientists from Indonesia, Australia, and the United States came to the same conclusion by examining bone and skull structure (Jacob (2006))[18]

A cast of LB1 (left) was compared to several microcephalic skulls, amongst which that of the microcephalic (right) used by Henneman in his attempt to present LB1 as a microcephalic. Argue (2006) and Lyras (2008) contend the opposite.

Brown and Morwood countered by claiming that the skeptics had drawn incorrect conclusions about bone and skull structure and mistakenly attributed the height of H. floresiensis to microcephaly.[44] Falk's team replied to the critics of their study (Falk et al. (2006)).[24] Morphologist Jungers examined the skull and concluded that the skeleton displays "no trace of disease". Argue, Donlon, et al. (2006) rejects microcephaly and concludes that the finds are indeed a new species.[17][45]

Falk et al. (2007) offered further evidence that the claims of a microcephalic H. sapiens were not credible.[5] virtual endocasts of an additional nine microcephalic brains and ten normal human brains were examined, and it was found that the floresiensis skulls are similar in shape to normal human brains, yet have unique features which are consistent with what one would expect in a new species. The frontal and temporal lobes of the floresiensis brain were found to be highly developed, completely unlike the microcephalic brain, and advanced in ways different from modern human brains. This finding also answered past criticisms that the floresiensis brain was simply too small to be capable of the intelligence required for the members of H. floresiensis to create the tools found in their proximity. Falk et al. (2007) conclude that the onus is now upon the critics that continue to claim microcephaly to produce a brain of a microcephalic that bears resemblance to the floresiensis brain.

Falk's argument was supported by Lyras et al. (2008) in that 3D-morphometric features of the skulls of microcephalic H. sapiens indeed fall within the range of normal H. sapiens and that the LB1 skull falls well outside this range. This was interpreted as proving that LB1 cannot, on the basis of either brain or skull morphology, be classified as a microcephalic H. sapiens.[19]

In 2009, a study by Jungers et al. presented a statistical analysis of skull shapes of healthy modern humans, microcephalic humans, and several ancient human species, as well as H. floresiensis. They showed that the three grouped separately, with H. floresiensis among the ancient humans, providing evidence that H. floresiensis is a separate species instead of a diseased modern human.[12]

Laron syndrome argument

The anatomist Gary D. Richards raised the argument in June 2006 that the skeletons from Flores might be the remains of people who suffered from Laron syndrome, a genetic disorder first reported in 1966. The next year, a team including Laron himself published a paper arguing that the morphological features of H. floresiensis are essentially indistinguishable from those of Laron syndrome.[46] The team said that to determine whether the H. floresiensis individuals had Laron syndrome would require testing their DNA for the presence of the defective genes, if samples of that DNA ever become available.[47]

Bone structure

Cast of the entire LB1 specimen

The bone structure of H. floresiensis’ shoulders, arms[9] and wrists[7] have been described as very different from modern humans, much closer to the bone structure of chimpanzees or an early hominin. This adds support to the idea that H. floresiensis is a separate species of early human rather than a modern human with a physical disorder.

Susan G. Larson et al. analyzed the upper limb of LB1. They found that LB1’s arm torsion is unusually low, much lower than that of modern people. This had been previously studied by G. D. Richards et al., who declared that it is a sign of modern pygmy populations, and T. Jacob et al., who pointed out that muscle attachments on the bone suggest LB1 had weak muscles which resulted in little development of humeral torsion. Larson et al. opposed Richards’ conclusion, arguing that the arm bone twist of pygmy populations is usually similar to that of peoples of average stature. They argued that Richards et al. cited a 1972 paper which had studied a sample of six female Eastern Central African pygmies and this sample was too small to represent the whole population. Larson et al. also looked for some signs of microcephaly on the studied bones, but failed to find any.[9]

Larson et al. also studied a relatively short clavicle and unusual formation of the pectoral girdle. They compared their finding with a H. erectus skeleton, KNM-WT 15000, known as Nariokotome Boy, and suggested that the pectoral girdle of H. floresiensis was a transitional stage in human shoulder evolution.[9]

While some specialists, including paleoanthropologist Russell Ciochon of the University of Iowa, supported the conclusion, others, including Eric Delson of Lehman College, City University of New York, pointed out that the recent sample of H. floresiensis individuals is too small and that Larson’s research was based just on one shoulder bone.[26]

Tocheri et al. (2007) (including Morwood, Larson, and Jungers), compared three carpal bones believed to belong to LB1 with carpal bones of modern humans, some earlier hominids and African apes. They concluded that the carpals from the Liang Bua cave resembled ape carpal bones and were significantly different from the bones of H. sapiens, Homo neanderthalensis or even Homo antecessor, and that they were comparable to carpal bones of Australopithecus. The carpal bones of H. floresiensis were found to lack features that evolved with ancestors of modern humans at least about 800,000 years ago. These features are already formed during embryogenesis and therefore Tocheri et al. argue that it is improbable that the shape of H. floresiensis wrist bones could be a result of a developmental disease.[7]

This conclusion was challenged by Robert Martin, the leading living proponent of the microcephaly explanation, and Alan Thorne. Martin noted that no research has been done on wrists of microcephalic people.[8] Thorne maintained that the differences were small and that similar variation could occur with living modern humans. He also pointed out that the carpal bones had been found scattered in the cave and it was not certain that they all belonged to the same individual.[48] Michael Morwood of the University of Wollongong in Australia, a coauthor of the study, countered that there were also other features, such as the stature, body proportions, brain size, shoulder, pelvis, jaw and teeth which suggested that H. floresiensis is a separate species that evolved in isolation on the island.

The new species theory was also supported by a study of the lower limbs by a team which included most of the same scientists who had authored the upper limbs study.[27] One of the most notable differences found was that the feet were unusually flat, and large in comparison with the rest of the body. The big toe was described as unusually short, similar to earlier hominids, including Australopithecus.[28][28]

Endemic cretinism hypothesis

In 2008 Australian researchers Peter J. Obendorf, Charles E. Oxnard, and Ben J. Kefford suggested that LB1 and LB6 suffered from myxoedematous (ME) endemic cretinism resulting from congenital hypothyroidism and that they were part of an affected population of H. sapiens on the island.[13] This disease, caused by various environmental factors including iodine deficiency, is a form of dwarfism which can still be found among the local Indonesian population. Affected people, who were born without a functioning thyroid, have both small bodies and reduced brain size but their mental retardation and motor disability is not as severe as with neurological endemic cretins. According to the authors of the study, the critical environment could have been present on Flores approximately 18,000 years ago, the period to which the LB fossils are dated. They wrote that various features found on the fossils, such as enlarged pituitary fossa,[13] unusually straight and untwisted tops of the upper arm bone and relatively thick limbs, are a sign of this diagnosis. The double rooted lower premolar and primitive wrist morphology can be explained in this way as well. The oral stories about strange human-like creatures may also be a record of cretinism.

Falk challenged the premise of the Australian team's results. Studying computer tomography scans of LB1's pituitary fossa, she came to the conclusion that it is not larger than usual. Peter Brown, the discoverer of the fossils, declared that the remains of the pituitary fossa were very poorly preserved and no meaningful measurement was possible.

Cladistic analysis

A study published in July 2009 in the journal of human evolution, by a team led by Debbie Argue, used cladistic analysis to suggest that the remains are from a separate species of Homo.[11] The study describes two equally possible phylogenetic trees; one indicates H. floresiensis emerged between H. rudolfensis (1.86 Ma) and H. habilis (1.66–1.9 Ma), with the second tree indicating that H. floresiensis emerged after H. habilis.

See also

Notes

  1. ^ a b c d e f g Brown et al. 2004
  2. ^ a b c d e f g h i j Morwood, Brown et al. 2005
  3. ^ a b c d e f Morwood, Soejono et al. 2004
  4. ^ a b c d e Falk et al. 2005
  5. ^ a b Falk et al. 2007
  6. ^ FSU News 2007
  7. ^ a b c d Tocheri et al. 2007
  8. ^ a b New Scientist 2007-09-20
  9. ^ a b c d e Larson et al. 2007 (preprint online)
  10. ^ Guardian 2007-09-21
  11. ^ a b Argue, Morwood et al. 2009
  12. ^ a b Jungers and Baab 2009
  13. ^ a b c Obendorf et al. 2008
  14. ^ a b Nature 2004
  15. ^ The Age 2004-10-27
  16. ^ Smithsonian July 2008
  17. ^ a b Argue, Donlon et al. 2006
  18. ^ a b c d e Jacob et al. 2006
  19. ^ a b Lyras et al. 2008
  20. ^ Encyclopaedia Brittanica Online. Pygmy.
  21. ^ Fix 1995
  22. ^ Weber ch. 5
  23. ^ TIME 2005-04-30
  24. ^ a b Falk et al. 2006
  25. ^ Weston et al. 2009
  26. ^ a b Science 2006-05-19
  27. ^ a b Jungers et al. 2008
  28. ^ a b c New Scientist 2008
  29. ^ Science Daily 2004-10-28
  30. ^ Forth 2005
  31. ^ Telegraph 2004-11-02
  32. ^ Sereno, M.I. (2005). "Language Origins Without the Semantic Urge" (PDF). Cognitive Science Online. 3.1: 1–12.
  33. ^ Nature 2004-10-27
  34. ^ Agence France-Presse 2004
  35. ^ New Zealand Herald 2004-11-30
  36. ^ New Scientist 2004-12-11
  37. ^ Times Online 2004-12-03
  38. ^ a b c Sydney Morning Herald 2005-03-05
  39. ^ Scientist 2005-02-28
  40. ^ a b c BBC News 2007-01-25
  41. ^ Weber et al. 2005-10-14
  42. ^ Spiegel 2006-09-01
  43. ^ Los Angeles Times 2006-05-20
  44. ^ New York Times 2006-08-21
  45. ^ USA Today 2006-07-16
  46. ^ Hershkovitz et al. 2007
  47. ^ Science News 2006
  48. ^ ABC Science Online 2007-09-21

References

Further reading

  • Penny Van Oosterzee; Mike Morwood (2007). A New Human: The Startling Discovery and Strange Story of the "Hobbits" of Flores, Indonesia. London: Collins. ISBN 0-06-089908-5.{{cite book}}: CS1 maint: multiple names: authors list (link)
  • Linda Goldenberg (2007). Little People and a Lost World: An Anthropological Mystery. Minneapolis, MN: Twenty-First Century Books. p. 112. ISBN 978-0-8225-5983-2. OCLC 62330789.
  • Maciej Henneberg; John Schofield (2008). The Hobbit Trap:Money, Fame, Science and the Discovery of a 'New Species'. Kent Town: Wakefield Press. p. 159. ISBN 9781862547919.{{cite book}}: CS1 maint: multiple names: authors list (link)
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