The twenty first century saw joint Australian-Indonesian archaeologists embark on an important historical assignment of finding evidence of the migration of the modern man to Australia from Asia. Unexpectedly, they ended up discovering another human species later named Homo floresiensis as it was found in the Flores islands.
Due to its uniqueness and similarities with the Homo, it generates controversy as to whether it’s a Homo sapiens that underwent biological mutations and adaptive alterations or it’s a totally new species within the Homo (Bromham and Cardillo, 2007:398). However, it does appear that Homo floresiensis is a totally new and separate species, which evolved separately in the Flores Island.
This paper seeks to give a succinct discussion of the Flores species on the skeletal morphology as used by some evolutionary anthropologists to hold up the suggestion that Flores hominids correspond to an exceptional species within the Homo. This view contradicts with a submission that an antique population of Homo sapiens went through difficult times in terms of their survival in their natural habitat.
To appreciate this thesis, the paper begins by covering Insular Dwarfism while paying attention to the brain and bone structure, and neurological reorganization. Other critical areas to be analyzed and reviewed are Phylogeny, Microcephaly, and Laro Syndrome respectively, which have been advanced by some scholars as to explain why Homo floresiensis are/are not an exclusive species within the homos.
The island rule that proposes that primates do undergo somewhat predictable changes in their body structure and size do not really explain the variation between the Homo sapiens and the Homo floresiensis (Gordon et al. 2008:4652). This is because there is no discernible scientific reason to support that assertion and is therefore left as mere a speculation. In fact, Lieberman (2009:41) contend that Homo floresiensis are a true and independent species of the hominid.
It is appreciated by all anthropologists and archaeologists that LB1 is characterized by extremely small internal skull capacity compared to modern humans and most other Homo ruins, pointing to a possibility that this connection may lack isometrics, especially bearing in mind that the size range for LB1 lies way outside that of ordinary Homo (Gordon et al.2008:4652).
In terms of the bone structure, studies by different archaeologists reveal that Homo floresiensis are characterized by arms, wrists, and shoulders that are distinct from those of ordinary modern day man but which apparently are closer in, comparison, to those of the Chimpanzees and perhaps the entire early man category.
This succeeds in reinforcing the assertion that Homo floresiensis is a new and isolated species of the Hominid and not a physically challenged/ incapacitated modern man (Wong, 2009:69). With a cranial capacity of only four hundred and seven cubic centimeters, the Homo floresiensis specimen is very small and cannot be said to evolve from any ordinary homo species of the nineteenth century.
But with its highly structured cerebral cortex, laced up with unoriginal characteristics that manifest higher mental capacities, the likelihood is that such floresiensis species actually evolved from a common ancestry with the modern man. That could have been achieved through neurological reorganization with limited or no concurrent brain size increment (Falk et al. 2009:3).
With respect to phylogeny, there are those who hold the view that formation of a new species was feasible, and believe that insular dwarfing was the best available answer to the current hobbit controversy (Bromham & Cardillo, 2007:398). They contend that Homo floresiensis is purely and entirely a result of Island dwarfing of the Homo erectus on the Flores and the surrounding areas.
They hold the view that the limited environmental space in the Flores Island had made food availability a problem and therefore, this meant that the Flores inhabitants had to cut short their consumption. This essentially meant adaptive alterations with the consequence that even the body size had to shrink, leading to an even greater speciation of the Homo erectus (Gordon et al. 4654).
The primitivism of Homo floresiensis is revealed by the hands, that are underdeveloped compared to modern day man (in humerus and the carpals), implying an evolution of floresiensis from Homo sapiens. Given that not the hands alone, but also the foot, exhibited primitive tendencies, the researchers would have had a relatively easier time concluding and convincing us that, in deed, homo floresiensis was just but a dwarfed kin of the Homo erectus (Wong, 2009:69).
But this would not be possible given the fact that throughout the specimen’s skeletons, primitive and barbaric tendencies were notable. Though available artefacts portray the Hobbits as if they were modern, they were essentially just as primitive as the Stone Age men were.
With regard to microcephaly, Falk et al. (2009:6) have come out strongly to contend that the hypothesis does not hold especially that the brainpan had no malformed skull and brain. Appreciating that the LB1 cranial shape is significantly distinct from that of the Homo sapiens and Neanderthals fossils, and significantly alike, in morphology with non-Asian Homo erectus and Homo habilis specimens, microcephaly does not explain the variation.
This is because if it did, Falk et al. (2009:4) posit, it would not have sought to advance reasons that are essentially similar to those that were canvassed as to explain the distinction between the original Homo species and the modern Homos. In fact, a virtual interior cast of the skull belonging to Homo floresiensis electronically produced and analyzed by researchers, confirmed that any malformation was not the cause of such speciation.
Some researchers, like Falk et al.(2009:4), and Bromham and Cardillo (2007), in their studies contend that the Flores man’s skull was similar in terms of shape to the ordinary human brain – despite showing peculiar characteristics which were in tandem, anyway, with the general expectation with any emerging species. This was proof enough that microcephaly cannot be relied upon to explain the peculiarity of Homo floresiensis.
However, it should be noted that such a discredited microcephaly hypothesis appear to explain such variation to some extent. Some researchers, particularly Weber et al. (Falk et al. 2009:4654), while carrying out a survey involving both micro cephalic and ordinary humans, concludes that because the microcephalic’s skull size appeared to lie within the expected range of other ordinary humans, the microcephaly hypothesis assertion was not inconsistent. It therefore follows that the discovery was in deed a new species.
It is usually said figures do not lie. In spite of the relevant statistics, generated and applied in the study, unflatteringly pointing to the conclusion that the Homo floresiensis was in deed not micro cephalic, many still argue that it was abnormal. Instead of proving their assertions, they have decided to leave it as mere objections and speculations (Falk et al. 2009:3).
As to whether such a species was a result of a disease (endemic cretinism) generating from congenital hypothyroidism, those who propose such a school of thought believe that it was responsible for dwarfism.
While this could be true, critics argue that scans through computer tomography revealed no malformations of the pituitary as was suggested (Falk et al. 2009:3-4). It follows, therefore, that nothing was to be found in LB1’s internal skull to suggest pathology, even if it was to be proven that LB1 was deficient in the genetic syndromes that are characteristic of the small brain sizes in Homo sapiens.
This means that the endemic cretinism hypothesis does not explain the emergence of Homo floresiensis per se, but it does surely explain dwarfism. While sceptics of the proposition that Homo floresiensis was an independent species advance the view that it was a disease that stunted their growth, their arguments have been watered down by the intelligent proponents because what these sceptics are proposing is not valid, at least to the extent that it fails to go beyond mere speculation.
In concluding, the onus is now with those of the view that the Homo floresiensis is just not a new species to justify and convince us as the burden of proof lies almost entirely on them (Bromham and Cardillo, 2007:400). They have to prove beyond reasonable doubt that Homo floresiensis, in deed, did suffer from some form of pathology (microcephaly) that rendered them inferior to other Hominids.
However, this will certainly be possible if a sample is taken from the micro cephalic (H. floresiensis) and Homo sapiens with some form of pathology that is known in order to compare. So it can be said now that Homo floresiensis is nothing short of a new species in the human kingdom. But future scientific findings that might contradict this position are highly encouraged.
Reference List
Bromham, Lindell and Cardillo, Marcel 2007 Primates follow the ‘island rule’: Implications for Interpreting Homo Floresiensis. Biology Letters 2007(3):398-400.
Falk, Dean and others 2009 LB1’s Virtual Endocast, Eicrocephaly, and Hominin Brain Evolution. Journal of Human Evolution 2009:1-11.
Falk, Dean and others 2009 The Type Specimen (LB1) of Homo floresiensis did not have Laron Syndrome. American Journal of Physical Anthropology 2009: 1-12.
Gordon D. Adam, Nevell Lisa, and Wood Bernard 2008 The Homo Floresiensis Cranium (LB1): Size, Scaling, and early Homo affinities. The National Academy of Sciences of the USA 105(12):4650-4655.
Lieberman E. Daniel 2009 Palaeoanthropology: Homo Floresiensis from Head to Toe. Nature 459(7): 41-42.
Wong, Kate 2009 Rethinking the Hobbits of Indonesia. Human Evolution: 2009:66-73.