Because Homo Floresiensis had Down Syndrome, doesn’t mean that Hobbits didn’t exist -Humans in the Making?

Explain this Darwin
Speak to me only with thine eyes…

Homo floresiensis

According to the Australian Museum, Homo Floresiensis (the species of very small humans often referred to as hobbits)

“…archaeological evidence suggests H. floresiensis lived at Liang Bua from at least 95,000 to 13,000 years ago. These dates make it the latest-surviving human apart from our species H. sapiens”.
– See more at: http://australianmuseum.net.au/Homo-floresiensis#sthash.nCcL6FH5.dpuf

 

They go on to say that these remains of humans are:

“One of the most controversial and surprising hominin finds in a century…

Conflicting interpretations and debates surround the remains of these tiny humans from Indonesia. H. floresiensis are not our ancestors but their unusual features and recent survival suggests our human family tree is more complex than once thought”
The key points in the above extract, apart from our evolution is certainly more complex than hitherto imagined (see other blogs on human evolution on this site) in my opinion, based upon more recent re-assignment of the entire species of Homo Floresiensis (hobbits) to a non-distinct human species (No Hobbits allowed) because a single representative of this population, turns out to possibly have had Down Syndrom according to a recent article published in a scientific journal a few days ago, essentially throwing out the entire species of Homo Floresiensis even though the rest of the population were  small, had distinctive primitive and more modern features and lived over the course of 80,000 years on this island. See article below entitled: Flores bones show features of Down syndrome, not a new ‘hobbit’ human.

http://phys.org/news/2014-08-flores-bones-features-syndrome-hobbit.html
The reason being, apparently, that LB1 (named after the site and the fact that it was the first and main find – a scull in particular, which a great deal of focus and fuss and controversy has surrounded concerning the distinct ‘new human’ label or NOT) is the one with DS (Down Syndrome).  However, a slightly earlier science paper dating to May 2014 has outlined another interpretation based upon the same evidence within the wider context of other remains and artefacts from the same site as LB1 and the rest of the region in their paper entitlted: Evolved developmental homeostasis disturbed in LB1 from Flores, Indonesia, denotes Down syndrome and not diagnostic traits o f the invalid species Homo floresiensis http://www.pnas.org/content/early/2014/07/31/1407382111.full.pdf+html

 

This more integrated examination of the facts demonstrates that the main skull LB1 which is the one with the proposed DS (Down Syndrome) and often represented (reconstructed) in popular science outlets as the sole representative of this deminuitive species, essentially, are pointing out that we can’t throw out the baby with the bath water as the rest of this  distinctive human (small) species are well represented at the site and span a vast period of time and obviously don’t all have the DS condition.

In other words, LB1 may have had Down Syndrome (common enough amongst ourselves, chimps and apes etc), but it doesn’t make all the other hobbits (Homo-floresiensis) disappear because it may turn out that one of the population had this condition. If anything, in my opinion, it shows how having DS still meant that (LB1) she survived until about 30 years old and presumably she was well cared for by her family and community.

Otherwise, this distinct human species found at Flores had fully-modern type jaws, but were missing chins which all modern humans have. They had very strange primitive features in their wrists and their arms were rather long for their bodies. (primitive and modern mix of features), yet, judging by their hunting habits, they were in the main brainy. They hunted with rather sophisticated tools and points and cooked big beasties (remember these are quite small and seemingly not quite fully modern human yet). They of course walked fairly well by all accounts – on both feet, even if their feet were quite large (I wonder were they hairy?).

see http://australianmuseum.net.au/Homo-floresiensis

Yes, it is amazing what you find out if you look at all the evidence from one archaeological site and not just a clincal study of an isolated case of a syndrome and a brain scull. I do tend to have a bias here as I am an archaeologist and know how important context is. Anyway, essentially what I’m saying is that many of those rejecting the new species status focus only on the remains of LB1, and ignore the rest of this population and their remains/artefacts of stone and the geology of the site showing occupation by this same group for over 80,000 years, if not more, that show many of the same characteristic features as LB1 which are irrelevant to her possible DS condition. – See more at: http://australianmuseum.net.au/Homo-floresiensis#sthash.nCcL6FH5.dpuf

 

All in all, far too much has been made of one scull from flores (LB1). Yes, it was exceptionally small, but tests and endocastes of the interior folds of the frontal lobes (impressions made when brain case was more maluable) and show obviously different folding (modern human type) rather than anything resembling a chimps soft-tissue arrangements. In otherwords, even with the DS condition, LB1 was more human-brained than chimp-brained.

 

 

Below are more archaeological points on the Homo-floresiensis population as a whole from Flores.

Further fossil finds from Flores
Daniel E. Lieberman
New fossil discoveries on Flores, Indonesia, bolster the evidence that Homo floresiensis was a dwarfed human species that lived at the end of the last ice age. But the species’ evolutionary origins remain obscure

The new fossils
consist of the right humerus, radius and ulna
of the LB1 skeleton, the mandible of a second
individual (LB6), and assorted other remains
including two tibiae, a femur, two radii, an
ulna, a scapula, a vertebra, and various toe
and finger bones. The researchers think that
the sample includes the remains of at least
nine individuals.
The analysis focuses on the new mandible
(LB6), a new tibia (LB8) and the LB1 skeleton’s
reunited arm bones. Of the many details,
several merit special attention. First, the new
mandible is extraordinarily similar to the first
one. They almost certainly belong to the same
species. Both mandibles share distinctive
dental features, and they lack chins — a chin
being a unique feature of all Homo sapiens
regardless of their stature, including most
microcephalics (…).

In addition,
the new tibia and arm-bone fossils not only
confirm that the Liang Bua hominids were
short, about a metre tall, but also indicate that
they had relatively long arms…

Although the original LB1 skeleton is estimated to be 18,000 years old, a child’s
radius was found in deposits estimated to be 12,000 years old, and the new mandible is
estimated to be 15,000 years old; other finds may be as old as 95,000 years 2,3. The fossils also all seem to be similarly small, refuting the contention that the LB1 skeleton was simply an aberrantly dwarfed, pathological specimen. If they were pathological, then the Liang Bua fossils would have had to have come from a population of short,  microcephalic humans that survived for a long time, or one that was susceptible to high frequencies of microcephaly and dwarfism. Such possibilities strain credulity; moreover, a three-dimensional analysis of the LB1 braincast found the brain to be unlike a micro-cephalic’s, and more like that of H. erectus than H. sapiens
.

https://www.fas.harvard.edu/~skeleton/pdfs/2005d.pdf

And again from the Australian Museum website:

 

All remains come from the cave of Liang Bua on the island of Flores in Indonesia. Flores lies towards the eastern end of the Indonesian island chain.

Flores has always been separated from mainland Asia – even at low sea levels the water-crossing was at least 24 kilometres. It is known that other animals reached Flores by swimming or floating on debris. How or when H. floresiensis reached the island is unknown.

Jaws and teeth

  • lacks the bony point on the chin found in modern humans
  • relatively large jaw and teeth that resemble H. erectus but with more primitive features
  • premolar roots different from H. sapiens
  • small post-canine and canine teeth
  • parabolic or V-shaped dental arcade typical of Homo
  • bony shelf at the front of the lower jaw which is a primitive feature not seen in H. erectus

Limbs and pelvis

  • bones and joints of the arm, shoulder and the lower limbs suggest that H. floresiensis was more similar to early humans than modern humans
  • characteristic bipedal foot that includes a big toe aligned with other toes and a locking mechanism on the middle of the foot to help stiffen the arch after heel lift occurs
  • several primitive features include a relatively long foot for its body size (70% as long as the thigh bone, compared with 55% for modern humans), a flat arch lacking the spring-like mechanism used to store and release energy during running, and a short big toe. These features are similar to ancient hominins such as H. habilis (OH8) and australopithecines and suggest the gait was different from and less efficient than modern humans.
  • unusual low twist in the upper arm bone
  • wide leg bones compared to the length
  • relatively short and curved clavicle
  • shape of the shoulder blade resulted in the shoulder being moved forwards slightly as if hunched
  • wrist bones differ significantly from the those of modern humans and are more similar to African apes or australopithecines. They lack features that evolved with the ancestors of modern humans at least about 800,000 years ago. In particular, the trapezoid bone is pyramidal in form, whereas modern humans have a boot-shaped trapezoid.
  • primitive flared ilium blades in the pelvis, similar to australopithecines, and females have wider pelvises than H. sapiens females
  • relatively long arms

Lifestyle

Culture

Tools

Stone tools were found in a number of different layers dating from 90,000 to 13,000 years ago. Tools include simple flakes, points, perforators, blades and microblades which were possibly hafted as barbs. Some were found with the remains of LB1, but most came from the same location as the remains of the extinct pygmy elephant Stegodon. This suggests that H. floresiensis was hunting these small elephants. Stone tools produced by heavier percussion were also recovered from layers not associated with H. floresiensis occupation. These tools date to about 102,000 years ago. The makers are unidentified.

There has been some speculation that the stone tools associated with H. floresiensis were actually made by H. sapiens. The basis for this is purely the belief that humans with such small brains couldn’t make such sophisticated stone tools – there is no other evidence in support of this. However, those studying the tools claim they are not as sophisticated as they appear and regard them as ‘simple’.

Analysis of the residues and polish on some of the tools revealed they were used for working wood and fibrous materials, perhaps to make spear shafts or items such as traps. Cut marks on the Stegodon bones also suggest some of the tools were used to process meat.

Precursors to this tool kit may come from earlier sites on Flores. Tools excavated from Mata Menge (about 50km from Liang Bua) in 2004-5 are at least 700,000 years old, and those from the Soa Basin date to about 880,000 years old. Tool kits from both sites show some similarities and technological continuity with those found in Liang Bua cave. The identity of the makers is unknown, but they could possibly be ancestral to H. floresiensis.

Fire

There is evidence of the use of fire in Liang Bua cave. The remains of numerous juvenile Stegodon have charred bones, possibly indicating that H. floresiensis was able to control fire for cooking.

Other

There are no traces of pigments, ornaments or deliberate burials in the layers associated with H. floresiensis – all of which characterise the modern human levels from the upper parts of the cave.

Environment and diet

Flores is a heavily forested tropical island with mountain peaks reaching over 2000 metres. The environment during H. floresiensis time would have been similar. The nature of their environment and the limited food sources typical of such islands provides strong clues to the evolution of H. floresiensis. When a small population becomes separated, changes can occur very quickly. This particular environment favours reduced energy requirements with dwarfing a response to this. Several dwarf species, including Stegodon, have been recovered on Flores and other small islands.

This species shared the island with pygmy elephants Stegodon, giant rats and large lizards like Komodo dragons. Evidence of cut marks on the Stegodon bones from Liang Bua cave show that H. floresiensis was at least hunting and eating this animal.

– See more at: http://australianmuseum.net.au/Homo-floresiensis#sthash.nCcL6FH5.dpuf

Relationships with other species

Ancestry

When first discovered, it was suggested that H. floresiensis was possibly descended from Javanese H. erectus. However, more detailed analysis of skeletal remains has uncovered traits more archaic than Asian H. erectus and more similar to australopithecines, H. habilis or the hominins from Dmanisi in Georgia (classified as Homo ergaster or Homo georgicus). Most scientists that accept H. floresiensis as a legitimate species now think its ancestor may have come from an early African dispersal by a primitive Homo species similar in appearance to H. habilis or the Dmanisi hominins. This means that it shared a common ancestor with Asian H. erectus but was not descended from it….

Unfortunately, no transitional forms, or the actual remains of H. erectus itself, have been found in Flores. However, stone tools that may have been made by H. erectus (or a similar species) were discovered on Flores. These date to 840,000 years ago, so indicate that a hominin species was probably living on the island at that time. – See more at: http://australianmuseum.net.au/Homo-floresiensis#sthash.nCcL6FH5.dpuf

– See more at: http://australianmuseum.net.au/Homo-floresiensis#sthash.nCcL6FH5.dpuf

…All remains come from the cave of Liang Bua on the island of Flores in Indonesia. Flores lies towards the eastern end of the Indonesian island chain.

Flores has always been separated from mainland Asia – even at low sea levels the water-crossing was at least 24 kilometres. It is known that other animals reached Flores by swimming or floating on debris. How or when H. floresiensis reached the island is unknown.

– See more at: http://australianmuseum.net.au/Homo-floresiensis#sthash.nCcL6FH5.dpuf

Could a more archaic less specialised population of Homo Flores arrived (swam over – see aquatic ape theory & past posts on the hobbit species on  this site) to the island longer than our current model of evolution allows us to suggest?

A Generic Human on the way to being more specialised & you don’t even need transitional fossils to prove it? (see series on how humans evolved and how related are we to chimps really? etc on this site)

http://neuroscience.gmu.edu/people/abbutler.
Evolution of Vertebrate Brains
… reptiles did not give rise to mammals any more than mammals gave rise to reptiles. In regard to embryological development, it likewise generally proceeds from the general (common ancestral features) to the specific (specializations of the taxon) […]. What is clearly established is that all taxa have their own specializations. Each taxon has a mix of primitive features. http://brain.phgy.queensu.ca/pare/assets/Evolution2.pdf

 

The conclusion in this brain vertebrate study clearly indicates that the simplistic common descent model may be flawed. Indeed, increasing evidence suggests that all complex animals have evolved from their essential primitive form towards increased specialisation within their ecological niche.

 

Anyone reading other blogs on this site will recognise this theme. Basically, the most up-to-date scientific data not only strongly reputes our traditional simplistic common descent model of evolution, but also points to a new revolution in evolutionary thinking, where the complexity of life and speciation (change from one species to another) has unfolded according to continuous genetic exchange across distinct domains of life, a lot more hybridization between general and primitive classes of species than we have hitherto realised, in other words genetic exchange between both distinct forms of life (HGT – horizontal gene transfer) and via (vertical gene transfer – inheritance) between  and within a broad spectrum of life which would best be described as GENERIC blue-prints with flexible genomes that can be rearranged/reprogrammed and adapt an organism without changing the actual genetic code – life-forms of vertebrate/mammal/primate/great ape/human for example) leading to novel genetic diversity and therefore, an ever-increasing specialisation towards specific speciation.

 

Furthermore, highly sophisticated natural genetic engineering (See Shapiro throughout these blogs) has in effect sculpted genomes (and therefore the diversity of species) as adaptive mechanisms have themselves evolved which are driven ultimately by developmental/environmental factors (see articles on epigenetics and EVO-DEVO embryonic development etc), then populations adapting to inceasingly specialised niches until their genome become relatively stable and all variations on the specialised them of say a distinct human species could be continuously fine-tuned (micro-evoltuion at an epigenetic level) until these Hobbits became the living ancestors of many modern Indonesians and particularly those from Flores? Heresy, for some I know. But, truely this is the type of scenario unfolding as we apply the more recent data, particularly the molecular data, to what we find in the fossil record.

 

Take for example the fact that it doesn’t matter how big your brain is – it is how you use it. The article below deals with the non-gene difference between humans and chimps and it is to do with Transcription factors – how genes are expressed, which is ultimately controlled by epigenetic processes/natural genetic rearrangements of genome and these are orchestrated according environmental cues.

Transcription factors guide differences in human and chimp brain function

Summary:1
Humans share at least 97 percent of their genes with chimpanzees, but, as a new study of transcription factors makes clear, what you have in your genome may be less important than how you use it. Gene regulatory networks differ between human and chimp brains, the researchers found. Humans share at least 97 percent of their genes with chimpanzees, but, as a new study of transcription factors makes clear, what you have in your genome may be less important than how you use it.
The study, in Proceedings of the National Academy of Sciences, found that broad differences in the gene activity of humans and of chimpanzees, affecting nearly 1,000 genes, appear to be linked to the action of about 90 transcription factors. Transcription factors are proteins that bind to specific regions of the DNA to promote or repress the activity of many genes. …”Our very strong bias is to believe that these transcription factors are involved in speciation and traits that make species unique,” she said.
[…]
“The chimp network looks very much like the human one except there are a few transcription factors in different positions and with different connectivity,” Stubbs said. “Those are of interest from the point of view that they signal a major gene regulatory shift between species, and this shift may help us explain some of the biological differences.”
The new findings indicate that certain transcription factors are working together in a coordinated way to regulate the changes in seen in gene expression between humans and chimps, the researchers said.
“Once this network of transcription factors is established, changes in the network can be amplified because transcription factors control other genes,” Nowick said. “Even a small change in transcription factor expression can therefore produce a large effect on overall gene expression differences between chimpanzees and humans.”
http://www.sciencedaily.com/releases/2009/12/091207151220.htm

 

So, although I’m not saying that the Hobbits of Flores were anything to do with chimps, I am saying that when chimps weren’t chimps and humans weren’t fully human, they may have been generic apes on their way to becoming rather rapidly by all accounts, distinct from each other and it may have been something as simple as their interbreeding habits and how genes and proteins are regulated (expressed) via transcription factors and natural genetic engineering processes that are ultimately driven by environmental factors that may have made the difference in the end.

 

Therefore, in the light of newer ways of seeing the fossil record and our own evolution and its application to to the Hobbits of Flores, another way of interpreting all this evidence is to see this long-established variation of the generic ape/human template according to a very specific island niche, where hybridization, which was more common than previously understood between all sorts of archaic and more modern humans, when combined with isolation within this region and interbreeding within their own kind thereafter, problably did lead to the creation of the more modern populations around the island of Flores as the indiginous people themselves claim.

 

Just a thought!

 

 

Cheers

Maria Brigit (P.S. in the video – The Hobbit of Flores Island: Body and Soul, she dismisses the association and validity of tools found at the site as belonging to the hobbits of Flores. Just remember she is not a stone-tool specialist, although she is an endocast specialist, I’ll have to pull rank on this one. My phD specialism is prehistoric stone tools and I can safely say she doesn’t know what she’s talking about regarding the associated stone tools)

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2 thoughts on “Because Homo Floresiensis had Down Syndrome, doesn’t mean that Hobbits didn’t exist -Humans in the Making?

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