According to the main researcher, "difference does not indicate uniqueness. The characteristics in the original report are not so rare that they would require the invention of a new species of man."
In October 2004, the remains of a human skeleton (probably a woman) were discovered in excavations from the island of Flores in Indonesia, which was announced as the most important find of the last century in everything related to human evolution. His discoverers called him - Homo fulrasensis, a name that they say indicates that he belongs to a hitherto unknown species of man, perhaps as close and distant as the Neanderthal man.
However, a detailed re-analysis by an international team of researchers shows that this individual on which the classification of the species depends and which is known as LB1 does not represent a new species at all. Instead, it is the skeleton of an unusual person, and according to the researchers contains novel features consistent with a diagnosis of Down syndrome. The researchers published their findings in the August 4, 2014 issue of the journal PNAS of the American Academy of Sciences.
"The skeletal samples from Liang Boa Cave contain the broken remains of several humans," said Robert Erckhardt of Pennsylvania State University. According to him, only a skull and femur survived from LB1. All the other remains belong to other people, and all of them except him - have normal characteristics. Since the discovery of LB1, the cave has been explored repeatedly but no other finds have been found.
The initial definition of the species Homo fluorescensis focused on the abnormal characteristics of LB1: a skull volume of 380 cm1.06, which indicates a brain the size of about a third of a modern human brain, and the fact that the height of the individual was 1 m. Although LB15 lived XNUMX years ago, the comparison has been made with earlier hominins including Homo erectus and Australopithecus. Other characteristics were unique to it and therefore caused it to be defined as a new species.
A thorough examination of the findings again in a clinical setting allowed the researchers to propose another explanation.
First, they determined that the estimates regarding his brain volume and height were biased downwards, and that his brain volume is about 430 cc and that his height may also be higher because people with Down syndrome have a smaller femur compared to healthy people of similar height.
According to Eckhard, "difference does not indicate uniqueness. The characteristics in the original report are not so rare that they would require the invention of a new species of man," he said.
"When we first saw the bones, several of us immediately recognized the developmental abnormalities," Eckhart said. "However, we could not provide a complete diagnosis because the bones were broken. Over the years, several lines of evidence have converged into the understanding that it is Down syndrome."
The first evidence was the asymmetry of the skull typical of people with Down syndrome and other syndromes. Eckhart and his colleagues commented on this asymmetry as early as 2006, but the assessment was not included in the excavation team's report and was later dismissed as a result of the skull being buried for a long time.
A previously unpublished measurement of the forehead allowed the researchers to compare LB1 to clinical data routinely collected from patients with developmental disorders. Here too, the brain size is within the expected range for Down syndrome patients, who are born in Australia and Indonesia.
The short femur of LB1 not only considering the reduction in height that we see in Down syndrome patients, Kahrt said, but also statistically correct even with normal growth, indicates a height of 1.26 meters, a figure similar to that of humans living today in Flores and the surrounding areas.
According to the researchers, these and other characteristics of Down syndrome are found only in LB1 and not in the remains of other skeletons from the cave, indicating that LB1 is abnormal.
"We not only told a story but also tested the hypothesis of whether the skeletons from Liang Boa Cave are so unusual that they require the invention of a new human species?" Eckhardt asked. "The reanalysis shows that they are not unusual, so the developmental problem should be looked for. The signs we discovered are clearly compatible with Down syndrome, from which one in a thousand newborns suffer."
- For news from 2004 - A dwarf human race has been discovered that lived in Indonesia until 12 thousand years ago
- Just because you have a head the size of a grapefruit doesn't mean you're not human
- And skeptical news from 2005: neither a Hobbit nor a plasterer - just a woman who suffered from a rare bone disease
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Father, PNAS is the journal of the US National Academy of Sciences, not the American Association of Sciences.
Father, PNAS is the journal of the US National Academy of Sciences, not the American Association of Sciences.
The title is indeed as inflated as the Hobbit theory. For the attention of the editors.
All the researchers are saying here is that there is not enough data to justify a major change in the conclusions built on the basis of the previous data. This is the well-remembered "Ockham's Razor" principle.
If the data can be explained on the basis of differences in the known human races, there is no justification for deciding that a new human race will be discovered. But the researchers do not say that the findings are of ordinary Homo sapiens that received an imaginary interpretation. This is definitely a unique individual and also its human environment, the remains of the other individuals found, are not quite average.
If we look carefully for dwarf human populations all over the planet today, we can surely find individuals who, due to a genetic defect, are even much more dwarf than the general population. It is possible that this is what the excavators found in Flores, and if it is possible then there is no justification for an explanation based on a change in the definitions of the human species.
And it is still possible that this explanation is correct, and it will be possible to confirm the hobbit theory if more findings are discovered.
The archeology is not over yet...
All the tools on the site are typical for Homo Sapins. This was one of the mysteries, how it was possible that the new species created tools identical to the Sapins tools. Associating the skeleton with a Sapins individual with Down syndrome also solves the problem of the tools, now they fit the population.
The article itself is a good example of skepticism. A true scientific investigation should try to question everything, and the onus of proof is on the one who innovates something.
Only this is what distinguishes science from all pseudo-sciences of all kinds.
The problem is that the data is confused with the interpretation.
A human skull and dwarf bones were found. This is a given.
The statement that this is a new species of man is an interpretation. is a theory. She doesn't have enough credentials.
Equally, the conclusion that this is a person with Down syndrome, as described in the article, rests on very weak evidence.
According to them, they found that the sizes of the bones correspond to the size range of people with Down syndrome. Does this necessarily mean that this is the reason for the small bone size? This is only supporting evidence, but it is not sufficient to establish a definite conclusion.
There is no need to blow up balloons nor inflate them in the first place.
To get closer to the truth you have to stay with the data. Today the data is: small human bones were discovered and a group of researchers claims to have found them to be in the appropriate range for Down syndrome.
I would change the title of the article as follows:
The end of the Hobbit legend? It is possible that the "new species" is a person (probably a woman) with Down syndrome.
But then maybe there will be less ratings?... Basa.
A rare breed of researchers has been discovered…..
It's good that there are decent researchers who have the courage to blow up balloons. Who knows how many additional findings from which erroneous conclusions were drawn did not undergo a thorough and fair enough examination.