The debate around the status of the homo floresiensis
Carlos A. Marmelada
carlosalbertomarmelda@yahoo.es
October 2007
-
The announcement of a
surprising news
-
The first finds of Morwood
-
The discovery of the Man of the
island of Flores
-
Why was the Homo floresiensis so
small?
-
The first criticisms
-
-
Microcephalia and
dwarfism
-
Too much advanced
technology
-
The bones of the discord
-
The analysis of the
computerized tomography (TC) of the skull of LB 1
-
Criticisms and
countercriticisms to the article of Falk and colleagues
-
The reply of Falk et. al.
-
The new criticisms
-
The reply of Falk and his
collaborators
-
The new discoveries
-
The lithic industry of Mata
Menge
-
The new criticisms
-
New facts about the cranium of
the LB 1
-
The shape of the brain in
microcephalic humans and in the Homo floresiensis
-
The study of the lithic
industry from the Asian Southeast
-
The structure of the shoulder
of the Homo floresiensis
-
The structure of the wrist of
the Homo floresiensis
-
The uncertainty regarding the
origin of the Homo floresiensis
On the 28th October, 2004 a news which shocked the world of
Science hit the headlines all over the world. In fact, that very
day the prestigious magazine Nature published two articles
1 which
astonished many specialists in human evolution. In these articles Peter
Brown and Michael J. Morwood (both professors at the New England
University in Armidale, Australia, and codirectors of a mixed group of
investigation formed by Australian and Indonesian scientists) announced
they had discovered the partial skeleton of an adult female human who had
died 18,000 years ago in a cave in the Indonesian island of Flores
2. It was no
more than a metre tall and had a brain of 380 cc., a brain volume
slightly smaller than that of more than three million of years ago
hominids, such as the Australopithecus afarensis, and similar to the one
of the chimpanzees (380 cc.). According to the discoverers it
corresponded to a healthy individual who, as a result, was assigned to a
new human species: Homo floresiensis 3.
Obviously the news was so shocking that it seemed even a joke. Juan Luis
Arsuaga said from it in ABC: “Until yesterday 4 I thought that to play a joke on
a paleoanthropologist colleague I would tell them that an australopitecus
had appeared in a place of La Mancha whose name from that moment onwards
will always be remembered all over the world. What the magazine
Nature tells us is much more surprising and however, we have to
admit it is true. At least for the moment” 5.
The final tag is precisely the key point. We are going to develop this
essay about it. The announcement of its discovery was so surprising that
soon many skeptical voices arouse. Nevertheless, not only its discoverers
but also a great number of scientists have refuted one by one all the
criticisms to the thesis that the Homo floresiensis is a human
species different to us or to any other, with the peculiarity of having a
very small height, a scarce metre (we repeat that we are dealing with
adult and healthy individuals) and a tiny brain around 400 cc.; and,
however, intelligent enough to make complex stone tools as the ones of
our direct ancestors the Homo sapiens 20,000 years ago; and more
important things as we will shortly see.
What we are going to analyse is, precisely, the historical development of
that controversy. That is to say, the analytical chronicle of the debate.
We will logically start by paying attention to what Brown and Morwood
stated in the before mentioned articles. Then we will focus on the
criticisms they received and analyse the first replies and so on and so
forth until we arrive to the last works published this year. But before
we will see the results of the first works of Morwood in Flores.
Mike Morwood, one of the codirectors of the team who discovered the
Homo floresiensis, was several years working on the island of
Flores. In fact, in 1998 announced the discovery of lithic industry close
to 800.000 years old 6. Though it was impressive the so old existence of
stone tools in that area, which it was really amazing of that discovery
was none of the two, because, in fact, samples of lithic industry were
already found with a similar or superior age in the Indonesian
archipelago. Where did the remarkable facts of this discovery lie? Not
surprisingly, in the very exact place of its discovery: the island of
Flores.
Why? For the simple reason that Flores was never united to the continent.
That is, it has always preserved the status of insularity independently
of weather variations of the planet which provoked that the water
concentrated on the poles when the temperatures were low, with the
consequent regression of the seas and the increase of the surfaced
continental platform, something which favoured that many of the current
islands which exist in the world and that are near to the coast were
united to it by an arm of land. This was never the case of Flores;
however there have been times when great parts of the Indonesian
archipelago (all its central and western part: Java, Sumatra, Bali,
etc…) were united to the current peninsula of Malaca (o Malaysia);
and, generally speaking, to all the Asian South East (Malaysia, Thailand,
Vietnam, Camboya or Kamphuchea and Laos), forming the geographic unity
known as the Peninsula of Sunda or Sonda. Flores was always separated
from this peninsula by a waterspout, the so called Strait of Komodo.
What does all this mean? Something quite obvious: that the makers of
these stone tools had no other way to arrive in Flores but by sea. That
supposes something quite unusual and unexpected.
Up to 1988 it was believed that the oldest proofs of navigation were
60,000 years old (60 kyr.) 7 and corresponded to the first crossing of the
northern Australia by members of our species, Homo sapiens, who
arrived in the area by sea.
Nowadays the space which separates Flores from Java is marked by a number
of islands, among whom Bali, Lombok, Sumbawa and other smaller ones such
as Comodo, which is just in the western strip of land of Flores, stand
out. From all these islands the ones situated more to the west were part
of the before mentioned Peninsula of Sonda. That was not the case of the
ones towards the east. However they could have an important role as they
allowed for “frog jumps”, which favoured the navigation to
Flores. In any case, the human presence in that island more 80,000 years
ago makes us think a lot.
However, at first, not everybody agreed on admitting that the origin of
those tools were anthropic. The skepticism came mainly from the fact
that Flores had never been united to the continent; which means that
those humans had to have arrived to Flores sailing through the dangerous
Strait of Comodo. If that was so, then the erectus should be
considered the first sailors in the history of humankind. Privilege given
up to that moment to the sapiens who, almost seven thousand years
alter, were able to arrive in Australia from some island of Indonesia.
Truly it was something rather shocking to be accepted as such.
Nevertheless the controversy was settled in the summer of 2006, with the
publishing by Morwood and collaborators of a work in which he announced
to have discovered 507 new tools dating between 840 kyr. and 700 kyr ago.
But we will be referring to them later because they have a very important
role in relation to the Homo floresiensis.
Let’s go back to the year 1999. In that moment Morwood decided to
undertake new excavations in other locations, so that he could confirm
that the humans had arrived in Flores in very early times. In order to do
so they were heading towards the cave of Liang Bua. In the campaign of
the summer of 2003 the researchers came up against a great surprise. In
fact, when they were working in the sector VII, they unearthed several
human remains including a human tiny brain: all the remains corresponded
to the same individual and were at a level 18,000 years old. By the
pelvis shape they concluded it corresponded to a female and by the wear
of the teeth deduced she had died when she was about 30 years old. Her
small height, around a metre, made them think for a moment she would be a
young girl. But when they noticed the wear of the teeth and the presence
of the wisdom tooth they had no other choice but to accept a really
surprising fact: it was an adult individual! With all the implications
that deriver from it. Her small height was therefore not a question
related to her age of death, but a specific feature.
The fact she had a similar height to the ones of the
Australopithecus and the first humans (Homo habilis and
Homo rudolfensis) and a similar brain to the one of the
chimpanzees, but with an excellent talent to make very complex tools, as
well as the possession of other archaic anthropological features, led
their discoverers to include these specimen in a new human kind: Homo
floresiensis.
It could be possible to think they could have come up against an
individual of our kind but exceptionally short due to some anomaly of its
growth. However this hypothesis was ruled out by them, as the research
team had found previously, in other site of the island, a fragment of an
arm, from another individual of the same kind, but 38 kyr. old, which
suggested that the individual to whom it belonged was also around a metre
tall. Its discoverers rejected it belonged to our kind but rather it was
a pygmy, as the physical development of these sapiens stops at the
end of the adolescence, but then their brain has reached a size as big as
the one of any other sapiens, whereas “Hobbit”
9 died
being an adult woman.
In this sense and in an anecdotal way we may remember that Henry Gee,
director of the Nature magazine, warns that this discovery should
lead us to redefine the degree of veracity given to the legends explained
by the natives of the island to the Dutch sailors who landed there;
stories which referred to the existence of mysterious humans (the ebu
gogo) who were around a metre tall and lived inside the wood.
A form the herbivorous species have to defend from their predators is to
resort to the megadontia, that is: to develop an enormous growth of
their organism to avoid or make difficult to the carnivorous ones to eat
them. However in the absence of predators when a quite big population of
herbivorous is geographically isolated in a small area where there are
scarce food resources the only way to survive is to reduce their size
(so, for example, in the island of Sicily the elephants reduced their
size as much as only 250 kg.), so that after a time this population
evolves giving rise to a new species that, although heir or descendant,
it is already different to the mother species.
At first Brown thought this evolutionary mechanism was the one which
allowed the emergence of the Homo floresiensis. A primitive
population of Homo erectus may have arrived sailing (something by
itself impressive) up to the island of Flores; there it would remain
isolated and it would evolve to give rise to these tiny humans. If that
was the case, it would mean, according to Brown, that the hominids and,
therefore the humans were subject to the same evolutionary forces than to
the rest of the mammals. That interpretation is not only reasonable, but
it is even also obvious: as it is something logical from a biological
point of view, as it is from a physical perspective men is ruled by the
laws of gravity, as any other body. The scientific and philosophical
problem lies in determining to what extent the brain can reduce its size
preserving all the intellectual abilities common to the humans. At the
end of the article we will deal with the topic of the current hypotheses
about the origin of the H. floresiensis.
We have to bear in mind that in spite of their small size, they were able
to hunt animals such us tiny elephants already extinct (Stegodon), mainly
the breeding; giant lizards, the famous dragon of Comodo, still existing,
and other animals such as: snakes, turtles, frogs, rodents (also giants)
and bats. As the bones of some of these animals have appeared reduced to
ashes, it is believed that the floresiensis had to have dominated
the fire.
In Liang Bua thousands of lithic tools have also been found used to skin,
quarter, tan or make holes. Many of these tools appear in sediments 78
kyr. old. We know H. sapiens did not arrive in Flores until 12
kyr. ago, so he cannot have been the maker of these tools. So then
… who is the maker of those tools of Flores, so similar to the
ones made by the neanderthals in that time in Europe and the
sapiens in Africa and other places around the world? At first
there was no complete certainty, because it could not be dismissed that
the anatomically modern humans may have arrived in the island much before
the fossil testimonies that have come to us. But in the summer of 2007
the issue seemed to progress well with the publication of the works about
the tools of Mata Menge before mentioned, and that we will be dealing
with more thoroughly later.
It is logical that before a surprising and revolutionary discovery such
as this some critical voices arise which tried to give a more
conventional explanation. In that sense Maciej Henneberg (from the
Department of Anatomical Science s, Medical School, University of
Adelaida, Adelaida 5005, Australia; the same university in which Morwood
y Brown work) and Alan Thorne (from the Research School of Pacific and
Asian Studies, Australia National University, Canberra, ACT 0200
Australia) insisted from the beginning that what it was really found was,
according to them, individuals who belonged to the same species but who
presented pathologies. So the Homo floresiensis was, in fact, a
Homo sapiens with anomalies on their growth, as they announced in
a small communication entitled: Flores human may be pathological
Homo sapiens 10. According to these scientists the most
acceptable explanation for the small brain size was the microcephalia. So
we would be facing members of our kind who had suffered from some type of
pathology of the growth. In fact the two scientists mention one of the
finds of the research team of Liang Bua as a fact favouring them. It is
about a radius, a bone of the forearm, found in the cave and which has a
length of 210 mm, which according to Henneberg and Thorne will be
equivalent to an individual between 1,51 y 1, 62 meters tall; parameters
within the range of variability of the Homo sapiens. As other
fact reinforces in other cave of the island of Flores, Liang Toge, was
found another skeleton of a Homo sapiens who lived 3,500 years ago
and who was 1,48 metres tall, however having only a brain capacity of
1204 cc 11.
The text in which these two scientists express their criticism end by
appealing to prudence and warning that not until new reasonably complete
brains are found the hypothesis that states that a quite common
pathology, as it is the case of the microcephalia, cannot be discarded
and could be the cause of the morphology discovered in Liang Bua.
The reply of Brown and Morwood was conclusive, maybe too much, because it
even reached the argumentation ad hominem. What it was really
devastating was the content of the countercriticism. In fact, the
codirectors of the works of Liang Bua declare to own human remains
belonging to seven different individuals, all of them coming from the
same cave and all with the same body, dental and facial proportions as
the specimen LB1. The authors of the reply wonder, quite sensibly, if
there is any possibility that all these individuals are a group of
unhealthy types. The answer is that it is quite unlikely, above all if we
take into consideration they are a minimum number of individuals which
correspond to a chronological rank spanning several dozens of thousands
of years. To reinforce their position, Brown and Morwood refer to one of
the found jaw and remind us it has no chin 12, a distinctive feature of the
Homo sapiens, as it is an exclusive morphological feature of our
kind. In fact, no other human kind has chin. So, the individual to whom
that jaw corresponded should accumulate two abnormalities: lack chin and
suffer from dwarfism; likewise the female of Liang Bua had also two
pathologies: the microcephalia and the dwarfism. I n short, too many
coincidences together. Quite unlikely that each time an individual was
found in Liang Bua it was an unhealthy type who had arrived there, taking
also into account they were separated by thousands of years.
Marta Mirazón Lahr and Robert Foley, from the Leverhulme Center
for Evolutionary Studies, Department of Biological Anthropology,
Cambridge, also think it is impossible that the Homo floresiensis
is a pygmy Homo sapiens. According to these researchers, if we
compare the skull of the LB1 with the one of a current human person in
scale (that is, to a third of its normal size) both differ in shape,
robustness and a whole range of main features of the base of the skull.
To sum up, they do not have a specific similarity 13.
As far as the radius mentioned by Henneberg and Thorne is concerned,
Morwood and colleagues affirm it belonged to an individual no more than a
metre tall and that is why they assigned it provisionally to a Homo
floresiensis; though they admit as the postcranial remains assigned
to LB1 lack arms they cannot make a direct comparison between both
14,
something it could be corrected later, as we will be able to prove.
Other of the criticisms received is the one related to the statement of
the directors of Liang Bua regarding the lithic industry found there and
associated not only to a premolar of Homo floresiensis but also to
remains of Stegodon, was made by this species; which it would
show that in spite of the small brain size (let’s remember that
when its discovery was announced its endocranial capacity was estimated
in 380 cc.) they were very intelligent and quite skillful in the making
of complex tools, as much as the own Homo sapiens. However, among
the archaeological remains there is nothing comparable to pieces that
could be interpreted as art objects.
Tim Reynolds was one of the first ones in expressing his doubts regarding
the attribution of that technology to the Homo floresiensis
lacking more evident testimonies. Fair enough, for this researcher the
morphology of the lithic industry of Liang Bua is similar to the one
found in other places of the same geographical location and associated to
the Homo sapiens; so that, if the H. floresiensis were the
maker of the tools of Liang Bua we should postulate an evolution in
parallel with the technological development in that area, something quite
unlikely, so it is more convincing and conservative to think that the
artefacts of Liang Bua were made by members of our species 15.
The reply of Morwood and Brown is quite simple. The authors start by
admitting that, really, there is no unmistakable association of a rich
accumulation of lithic industry together with a big number of fossil
remains of Homo floresiensis, but rather the association in this
sense is quite weak, as it was stated before. That it is true, but there
is an interesting fact: Many of these tools appear in sediments that are
78 kyr. old. We know the oldest remains of H. sapiens found up to
now in Flores are 12 kyr. old. So it could not have been the maker of
those tools. Who was then the maker of them, tools so similar to the ones
made by the neanderthals in Europe and the sapiens in Africa in
that time? In that moment, there was no way to assure it.
Nevertheless the argument of Reynolds ends with very interesting words
that we wanted to emphasize apart from what it was said in the previous
paragraph. In fact, Reynolds reminds us that the oldest tools found in
Flores are the ones already mentioned before and that come from Mata
Menge, ranging from 880,000 to 800.000 years old; according to Reynolds
those tools do not bear any resemblance with the morphological standards
identified in Liang Bua and there is an enormous period of time between
both.
This is precisely what the team of Morwood has been able to clarify from
e Mata Menge. In fact, there Mark Moore, from the New England University,
and Adam Brumm, from the National University of Australia, have found
some tools 840,000 years old and bear a great resemblance (together with
certain differences) with the ones found in Liang Bua. The complexity of
these so old tools shows that the Homo floresiensis, much more
modern than the makers of those pieces, could very easily have been the
makers of the ones found in Liang Bua. If 800,000 years ago some humans
who lived in Flores (we do not know who, though we assumed they were some
population of Homo erectus) could make tools so similar to the
ones found in Liang Bua with a minimum of between 78 kys. or 18 kys. old.
Why could not the Homo floresiensis have been the maker of these
last ones? To assume that the reason is because the appearance is too
modern is not a reason enough to dismiss the H. floresiensis as a
plausible author. Such an argument could not be any other thing but a
form of ethnocentrism.
Leaving criticisms apart around the fossils found in Liang Bua there was
a real legal battle for its possession. At first Teuko Jacob was in
charge of them for an initial evaluation of the Bioanthropology and
Paleoanthropology Laboratory of the Gadjah Mada University of Indonesia.
He kept them on the first days of November thanks to the collaboration of
his friend Radien P. Soejono (from the Archaeological Centre of Indonesia
in Jakarta and who had also formed part of the team who worked in Liang
Bua) though with the condition that he should turn them back by the
1st January, 2005. However he was late for handing them in to
the team lead by the Australian researchers, so they started to feel very
nervous and Jacob was found suspicious of not letting their discoverers
examine them claiming they were property of the Indonesian government and
that their conservation and preservation demanded not moving them too
much. There was then a tough struggle for the right to study the original
fossils discovered in 16; which, besides, was even tougher from the
moment in which Teuko Jacob started to say in public that the remains
from Liang Bua were pygmies of our own kind, opinion shared by Soejono,
Henneberg, Thorne and Eckhardt 17.
At the end of March Jacob returned part of the fossils to the team of
Morwood and Brown. But then an unpleasant surprise was to come. Some of
the returned pieces were in very bad state, as some of the photographs
published by the newspaper USA Today 18 on the 22nd March, 2005 show. In
them the state of the pelvis and the jaw before being sent to the
Jacob’s Laboratory and in their return to Morwood and Brown’s
custody can be appreciated. The deterioration is quite evident in both
cases, though in the case of the pelvis the degradation is enormous, as
it was returned broken. The jaw did not have a better luck: in the
jawbone an incisor was missing; the inferior jawbone was broken into
several parts (the reconstruction has changed, necessarily, the features
of this jawbone zone); in the back upper part of the upper jawbone there
is a fragment of bone missing; besides an empty space has been created,
not existing before, between the canine tooth and the premolar one. To
sum up, something quite incomprehensible specially when we are dealing
with fossils of such a great value 19.
In the middle of all this controversy that very month (March, 2005) an
article by Dean Falk (from the Department of Anthropology of the Florida
State University) appeared and other ones 20 in which the conclusions of his
study about the skull of LB1 were exposed. The team directed by Falk had
analyzed the skull of the “Hobbit” female using the
computerized tomography. The conclusions to which they arrived were that
the three-dimensional analysis of the brain of the LB1 has revealed it
does not have the endocranial structure of a microcephalic individual,
but it shows a normal endocranial structure, though with very tiny
dimensions.
Regarding the endocranial volume there were also novelties. In fact, as
we mentioned before, when “Hobbit” was presented in society
in October, 2004 it was considered to have a brain volume 380 cc.; an
identical volume to the average one of the chimpanzees, and very far away
from the average 1350 cc. of the humans nowadays. The new volume
attributed to Falk team in that work was 417 cc. 21. This brain capacity is
included within the characteristic parameters of the graceful
Australopithecus of 3 million years ago, as it is case the of
Lucy.
However what called more the attention to the Falk’s team was the
structure of the brain. According to them they were dealing with a
specimen with a brain size common to the Austrolopithecus but with a
brain structure clearly human.
The way to determine the brain structure of the LB1cranium was from the
marks that the brain leaves in the internal face of the cranium. Though
the brain does not logically fossilizes what it really does is to leave
the marks of its external structure in the walls of the endocranium.
The study of the endocranium of the hominid of Liang Bua has revealed
several very important things. On the one hand it has allowed to know
that it had the temporal lobes very much developed, that is, the areas
that in our gender are associated to the language comprehension and in
which the area of Wernicke and the area of Broca are located, both
closely linked to the language abilities. the brain area which controls
the hearing is also situated in the temporal lobes.
On the other hand, the researchers could also verify that the frontal
lobe was very much developed, where the area 10 of Brodmann is located
which is the area associated to the control of the rational abilities and
to the planning of the future; this last feature seems to be essentially
and exclusively associated to the human kind.
These facts allowed Falk and colleagues to speculate with the possibility
that the Homo floresiensis was able to plan complex future actions
as well as dominate some form of spoken language.
The before mentioned study provoked a crossfire between various research
teams which lasted the autumn of that year and beginning of 2006. In
fact, the first criticisms came from Jochen Weber (from the Department of
Neurosurgery of the Hospital Leopoldina from Schweinfurt, Alemania),
Alfred Czarnetzki (from the Department of Paleoanthropology and Osteology
of the University of Tubinga, Alemania) and Castren M. Pusch (from the
Institute of Anthropology and Human Genetics also from the University of
Tubinga) when they published an article 22 in October, 2005, just a year from
the announcement of the discovery of these strange human, in which they
denied that the H. floresiensis were members of a species
different to our own one.
According to these researchers, after having analyzed 19 microcephalic
members of our own species, they proved that the average of their cranial
size was 404 cc., so the 417 cc. assigned to a LB1 by the Falk team was
within the level of variability characteristic of the microcephalic ones
of our species. Among the 19 specimen analyzed by Weber et al. there was
one who specially called their attention and towards which they focused
great amount of their time as it had a endocranial volume 415 cc.; very
similar to the one of the LB1. After studying six distinctive features
from it, they observe they were similar to the ones present in the
cranium of the LB1. They arrive to the conclusion that both the cranium
and the brain morphology of the 19 microcephalic individuals studied is
very similar to the shape of the cranium and to the brain structure of
the Homo floresiensis, so they refused to think it was a
different human kind to us and they chose the hypothesis which states
they were pathological individuals of our kind.
Regarding the commentary of the expectations that the drawing of the 10
area in the endocranium of the LB1 provoked, Weber et al. denied
it could be important as far as the speculations around the supposing
advanced cognitive abilities of the H. floresiensis were
concerned. According to Weber and his colleagues, a male microcephalic
individual studied by them had an endocranial volume of 485 cc. and well
developed area 10; however, though it was able to walk, it could not
talk. From it, they come to the conclusion that to extrapolate to a LB1
advanced cognitive abilities from the acceptable size of its area 10 was
too risky.
To start with the Falk team pointed out that Weber and colleagues made a
mistake in the relative calculations to the six features they studied in
a microcephalic brain of similar size to the one of the LB1, so they
calculations are invalid to establish extrapolations or comparisons with
the mentioned brain of the female of Liang Bua. They also observed that
the pictures offered by Weber and colleagues in their article are not
enlightening enough and even they may belong to different individuals.
They do not agree either with the reflections made around the area 10 of
Bordmann. In short, they find missing important facts in the Weber and
colleagues’ report, so their thesis are not conclusive regarding
the nullity of the hypothesis which states that the Homo
floresiensis is a different species to ours.
7 months after the appearance of these two articles in Nature,
the prestigious magazine Science published a new criticism to the
study made by the Falk team to the cranium LB1. However, it needs to be
said that the article had been received by the magazine on the 11th
October, 2005, that is, just a few days before the publishing of Weber
et al. Article in the same magazine as well as the reply of Dean
Falk et al. in Nature. This clarification is important
because at the same time as a number of crossing statements were being,
M. Morwood and his collaborators published an article in which new
discoveries were made public, so the publication of Science
regarding the commentary of Martin was a little obsolete considering the
new findings. But let’s not get ahead of events. We will first be
looking to the argument of Martin and his collaborators, as well as the
due reply of the Falk team and then we will study the new discoveries.
The criticism of Robert Martin and his collaborators 24 insisted on the idea
that the reduced dimensions of the brain of the female of Liang Bua were
not due to a tendency towards dwarfism suffered for a population of
Homo erectus in conditions of insularity giving rise to a new
human kind, but rather to an encephalopathy of some members of our
species.
In short, the habitual thesis which status that the specimen of Liang Bua
were ill Homo sapiens, more specifically suffering from
microcephalia. Disease to which we have to add the dwarfism and the
craniumfacial anomaly of the lacking of chin. In short: too many
pathologies in the same individual and the same sample of fossils.
Martin and collaborators warn that “european microcephalic”
25
specimen used in the study of the Falk team is in fact a plaster cast of
a cranium and not really an original fossil; adding that the calota did
not fit well with the rest of the plaster cast as it was varnished. In
fact, according to Martin and collaborators, the spectrometric study
confirmed that the calota belonged to a batch of plaster different to the
one of craniumfacial structure.
Martin and his colleagues also informed that Falk And his collaborators
had only in mind a kind of microcephalia and not the multiple variations
that this disease present, more than 400, which makes that the available
craniums of microcephalic individuals show a great variability, always
associated to genetic malformations. According to Martin and
collaborators, as there are more than a dozen diseases associated to
developmental delays syndromes and microcephalia, LB1 could be perfectly
be an individual born of humans of regular size.
Martin’s article finishes by stating that the found tools in Liang
Bua show a morphology more connected to the productions of the Homo
sapiens than to the Homo erectus ones.
To start with the Falk team refuses that the two craniums of
microcephalic individuals that Martin team possess, and that they state
are very much alike a LB1, are so in fact. According to Falk there are a
number of important features in which they do not coincide. Also they
warn there are many lacking facts (such as comparative measures, actual
pictures - in Martin’s articles there are only drawings -, and
identifying sketches of the most important features) to be able to
extract the most significant conclusions from the study of Martin and
collaborators.
Falk also denies that they do not bear in mind the great variety of
genetic syndromes associated with the primary microcephalia, contrasting
the opinion of the Martin’s team according to which the typical
pathology is the recessive autosomal inheritance, something that Falk
says is in conflict with what they have found in the specialized
literature.
Falk insists on the fact that the Martin’s statements related to
two endocraniums that would be similar to the one of Liang Bua lack
important facts to be able to determine the authentic grade of similarity
and so they cannot be taken into account to accept or refute one of the
hypothesis relative to the status of the Homo floresiensis.
Regarding the statement of Martin’s team about the tools of Liang
Bua, the works of Moore y Brumm about the found tools in Mata Menge
leave, as we will see later, that argumentation invalid.
At the same time as all these crossed declarations were being made in
October, 2005, though some were published in May, 2006, Mike
Morwood’s team announced they had found more remains of Homo
floresiensis, publishing a work about the study of some fossils
which were still unknown 27.
The new described material ranges from fossils of a three year old boy 50
cm. tall, to an adult who was even shorter than the species of 1 in Liang
Bua. Among these fossils there is a new jaw belonging to an adult
individual, and postcranium remains corresponding to several specimen, as
well as the arms of LB1, which were not originally found in 2003, and
which, consequently, allowed to make comparisons with other arm bones of
other individuals. In fact Morwood declares that the new material can
reconstruct the body proportions of the H. floresiensis with a
high degree of certainty, so we can affirm the morphology of these
specimen was a specific feature and not an abnormal shape produced by
some kind of pathology of individual character.
Their discoverers considered the found fossils had a chronological level
ranging from the twelve thousand years (date calculated according to
their extinction before the first humans of our species arrived in the
island, or at least this is what it is supposed for the moment) to the
ninety thousand years old for the oldest specimen.
The conclusions of Morwood and Brown from the new findings were clear.
The proofs were accumulating in favour of the thesis which states we are
in front of a new human kind who was able to survive 12,000 years ago.
The Flores’ men were humans who did not belong to our species. The
fact that all the found bones had dimensions proportionally small would
show that the partial skeleton of a female found in Liang Bua was not a
dwarf woman, but rather we would be in front of a human kind really
different to ours; and which has, as the most outstanding feature, a tiny
height.
Logically speaking, the duplication of fossil bones reinforces the idea
that the H. floresiensis corresponds to a population of tiny
humans specifically different from any other human type; ruling out the
possibility of the skeleton of LB1 would represent an individual affected
by a pathology (or several at the same time, as the opposite thesis
requires) or that it was some anatomically abnormal form of
sapiens.
Among the new announced discoveries there is a tibia whose size suggests
that the individual to whom it belonged was no more than 106 cm. tall,
who, for the moment, would be the tallest specimen of Homo
floresiensis found.
The article ends by placing on record that the origin of the Homo
floresiensis is still uncertain, but it states it cannot be said it
was a simple alometric version of Homo erectus; that is, that the
H. floresiensis do not descend from a population of H.
erectus who arrived in the island and were reducing their size.
We have referred in several occasions to the publication of a work about
the find of some stone tools in the site of Mata Menge, 50 km. away from
Liang Bua, with a maximum age between 800,000 and 880,000 years. The
collection covers about 500 small pieces and comparing them with the ones
found in Liang Bua, and whose age ranges from a chronological level
between 95,000 and 12,000 years, it can be seen a remarkable
morphological and functional similarity in most of them.
One of the arguments which supported the idea that the Homo
floresiensis was not the author of the lithic industry found in the
cave of Liang Bua was that their appearance was too much modern, so that
it seemed to be more the product of the Homo sapiens rather than
the result of the making of the tiny humans who had a brain as big as a
grapefruit.
The supporters of the Homo floresiensis as the maker of those
tools had against the fact there were very few fossils of that species
near the lithic industry. But the ones who stated that the responsibility
was of the Homo sapiens did not offer any more convincing
reasonings, as the oldest human remains anatomically modern found in
Flores were less than 12 kyr. old whereas there are tools morphologically
modern in Liang Bua found 95 kyr. ago.
The fact a collection of tools made 800 kyr. ago had been discovered in
Mata Menge with a so modern appearance as most of the ones found in Liang
Bua, means the Homo floresiensis may have been the maker of them.
However, this does not mean automatically it was, but only that it cannot
be denied they made them as their appearance is too modern and only
Homo sapiens could carve tools with so complex morphology. It was
not only that the Homo sapiens 8had not arrived in Flores 800,000
years ago but also he did not exist as a species. However, as there were
no human remains associated to the collection of Mata Menge we cannot
state either who was its maker, but the best candidate is the Homo
erectus as it was the only known taxon in the area at the time.
Nevertheless, as we will see later, other possible authors still not
discovered cannot be dismissed.
Brumm and Moore end up their article by reminding us the Homo
floresiensis disappeared 12 kyr. ago whereas the oldest burials of
Homo sapiens found in Flores were 10,500 years old and showed a
radical behavioural change regarding all previously mentioned including
the archaeological register related to the lithic industry. Finally, and
in the absence of evidences which state the opposite Brumm and Moore
affirm the most logical interpretation comes from supposing the group of
tools found in Mata Menge and Liang Bua represented a technological
continuity made by the same hominid lineage. To state the Homo
floresiensis lacked the brain size to make the mentioned tools was
based more in prejudices than in real evidences
When the summer of 2006 was ending, new criticisms appeared regarding the
status of the Homo floresiensis as a human kind with own entity.
Teuko Jacob, Radien P. Soejono, Maciej Henneberg, Allan Thorne, R. B.
Eckhardt et al. Were the ones who signed an article 29 in which they
defended again that the human remains found in Liang Bua were from some
Homo sapiens who had suffered from several pathologies.
According to these authors the found specimen found in Liang Bua came
from a population of pygmy Homo sapiens predecessors of the
Rampasasa who live now in the area. The found individuals in the before
mentioned cave of Flores would show, according to these researchers, own
individual signs of an abnormal development, including the
microcephalia.
It could be claimed it would be something quite unlikely as it would
imply these individuals should have been dwarf and microcephalic pygmies,
which it would mean they had suffered from too many pathologies at the
same time. However, the authors reply that the microcephalia goes
together, commonly, with a number of abnormalities 30.
We mentioned before the jaw of the LB1 lacked chin 31, something contrasted with
the own morphology of a Homo sapiens. However Teuko and his
colleagues supported that the 93,4% of the present pygmy Rampasasa have a
neutral and negative chin, that is, it is either too soft or they
directly lack it and the jaw turns to be evasive (that is, with a light
inclined plane backwards) in that area.
This month of September a new article of the Homo floresiensis was
published in the Journal of Human Evolution 32. In it its authors sustained that
the cranium of LB1 was not the one from a microcephalic individual, but
rather the one from a healthy individual of tiny height. This was in
support of the ones who consider the Homo floresiensis as a human
species different to ours. The authors come to this conclusion after
having studied the cranium of LB1 and having compared it with the one of
the first humans, two craniums of microcephalic individuals, a cranium of
a pygmy taken from another cave in Flores, several craniums of Homo
sapiens (which included the ones from some African pygmies and the
one from individuals from the Andaman islands – in the Indic Ocean,
in front of the coast of Thailand) Australopithecus and
Paranthropus, concluding it is very unlikely that the LB1 is
neither a microcephalic human, nor any other known species, so it is
reasonable to assign it to a new human species: Homo floresiensis.
The article ends up by dealing with the topic of the origin of these
amazing humans, something we will be discussing later.
In the year 2007 new works about the Homo floresiensis appear. In
February the Falk team published an article in Proceedings of the
National Academy of Science s (PNAS) 33 in which they reiterate from new
studies of the specimen no. 1 of Liang Bua, this could not be a
mirocephalic Homo sapiens. For that they have reconstructed in
three dimensions the endocraniums of 9 microcephalic individuals and 10
normal humans, using the computerized tomography. These virtual
reconstructions collect the marks left by the brain in the internal walls
of the endocranium, so that the external morphology of the brain is
reflected; they also allow to calculate the cranial capacity.
As the cranial capacity of the Homo floresiensis is only of 417
cc., some researchers have suggested we are rather dealing with a
microcephalic Homo sapiens than with an individual of a new human
species. This hypothesis is difficult to be valued without a clear
understanding of how the shape of the brain of the microcephalic
individuals is in comparison to the normal humans. The team led by Dean
Falk and Mike Morwood, using the computerized tomography, has made the
reconstruction in three dimensions of three endocraniums.
From the observations made in these casts, the researchers have been able
to identify two variables which allow to classify the brain in either a
normal or microcephalic one with a 100% guarantee of correct answer. From
these facts, the Falk team and his colleagues have been able to conclude
that the resemblance of the LB1 looks more like the one of a normal than
a microcephalic brain. According to these authors, the investigations
that have been carried out do not only allow to classify the brain of a
LB1 as normal, instead of microcephalic one, but also provide facts about
the genetic substratum of the evolution of the human brain and can be
very useful in order to make clinic diagnoses.
However, in spite of the fact that the brain of the LB1 shows features
that makes it very much more alike a normal human one than a
microcephalic one, there are as well a number of characteristics such as
its small brain size which are consistent with the fact of assigning it
to a own human species, that is, different to ours.
The microcephalia, that is: the possession of a sickly small brain, is a
condition according to which the adult ones reach a 400-500 g of brain
mass; which causes mental delays ranging from moderate to severe. Certain
works of investigation of cases of microcephalic individuals all over the
world have been spread. Quite commonly we are talking about a disease
result of blood unions.
Due to the controversy emerged around the status of the LB1, the authors
of the investigation have decided to study the endocranium of a
microcephalic woman with a brain volume similar to the tiny female of the
island of Flores. They have also studied the cranium of an adult
microcephalic woman who also had approximately the same height as the
female of Flores.
The virtual endocraniums were measured electronically to obtain the
cranial capacities used traditionally to express the brain mass. The
difference in size between the brain of the immature microcephalic
individuals and the normal humans was even inferior to the assigned
values given to the mature microcephalic individuals. This is so because
in these pathological individuals their maximum brain development is
reached sooner than in normal humans. From this point, the brain of the
mocrocephalic reduces its size.
The conclusion of the study is that the cranium of LB1 shows a bigger
number of similar features as the ones of a normal person (with the
exception of its size) than those of a microcephalic individual.
In another work by Mark Moore and Adam Bruma, they examine again the
present compression of the collections of lithical artefacts of the
Pleistocene in the Asian Southeast 34. Obviously, in spite of such an aseptic
title, this work needs to be framed within the controversial debate which
arose around the hominid status of the Homo floresiensis. The
mentioned discovery in Mata Menge of 800 kyr. old stone tools, with a
similar morphology to the one of the lithic industry associated to the
H. floresiensis, destroys the preconceived idea that only humans
of our species could be the authors of lithical instruments of so
advanced typology. In this new article, Moore and Brumm deepen in the
topics dealt in the published article in Nature in June, 2006.
According to the authors there is a difference made for a long time
between the collections of lithic industry of great size (groups of
tools) and small size industry (chips). The former is normally associated
with H. erectus, whereas the latter is connected with H.
sapiens. The authors affirm this traditional way to interpret the
Asian Southeast archaeological register in relation with the lithic
industry assumes the recovered artefacts in a site reflect a complete
technological sequence. After the analysis of the collections of the
artefacts from the Pleistocene found in Flores, the authors maintain the
thesis that the big groups of pebbles and the small chips are aspects of
a unique reduced sequence.
Moore and Brumm suggest to apply the model observed in Flores to the
artefacts from the Pleistocene of other islands of that geographical
area. The article ends by debating the implications of that form of
analysis of the archaeological register of the Asian Southeast
establishing associations between collections of lithical artefacts and
human species in the islands of that area.
So far, the last of the main articles published around the Homo
floresiensis, is one from Susan G. Larson’s team related to
the structure of its shoulder 35 and which appeared in August.
The authors of the study suggest that the articulation of the shoulder of
the Homo floresiensis had no similar structure to the anatomically
modern humans; that is, us. In their opinion, the collarbone is
relatively short in comparison with ours (taking into account its minor
absolute size) and the scapula was longer, which made movements more
frontal than lateral ones. As a whole, the shoulder’s morphology is
quite similar to the one of the Child of Nariokotome, or Turkana Boy, a
specimen of Homo ergaster or African Homo erectus,
technically known as KNM-WT 15000, found by the Richard Leakey and Allan
Walker’s team in Kenya in 1984. After comparing the equivalent
bones of LB1 with the right collarbone of the Child of Nariokotome
(KNM-WT 15000 D), the scapula (KNM-WT 15000 E) and the humerus (KNM-WT
15000 F) the authors of the study conclude the configuration of the
shoulder of the Homo floresiensis could suppose the transition
between the shown by the morpho represented by the Turkana Boy and the
Homo sapiens, so, whereas our shoulder is more prone to lateral
movements than that of the H. floresiensis, it would be more
adapted to frontal than lateral movements
Despite the clear differences between the features of the Homo
erectus represented by the Child of Nariokotome and the ones of the
H. floresiensis, shown by the partial skeleton of Liang Bua, we
have to recognize the group of bones which make up the shoulder are
closely related (collarbone relatively short, short degree of torsion
Huaraz, etc…). Because of that Susan G. Larson and colleagues
consider these similarities are not due to casual morphological
coincidences, but rather they are part of the expression of a functional
complex which had characterized the early Homo erectus and that it
was preserved by the Homo floresiensis. It would be, then, an
evolutionary development that had remained unknown until now. Finally the
authors focus on Dmanisi (Republic of Georgia) and warn that the new
discoveries of postcranial remains made in this Caucasian site (which,
strangely enough, they do not assign to a Homo georgicus, but to
an early Homo erectus from the Caucasus) could throw some light on
the topic.
A month after the publication of the article about the shoulder of the
Homo floresiensis, the magazine Science published a new
study about other element of the postcranial skeleton of this human
species. In this particular case, it was a research study about the wrist
of the LB1 skeleton made by the team led by Matthew W. Tocheri (from the
Department of Anthropology of the National Museum of Natural History of
the Smithsonian Institute of Washington) 36.
The study comes to very similar conclusions to the ones established after
analyzing the shoulder of this same skeleton and comparing in it with the
one from the Nariokotome child. The archaic morphology of the three bones
of the wrist analyzed confirm they are, by no means, similar to ours, but
rather they seem to represent a morphology dating back 800,000 years
which means that the anatomy of the wrist of the Homo floresiensis
was not present neither in the Homo sapiens, nor in the Homo
neanderthalensis nor, even, in the last ancestor common to both of
them.
The morphology of the wrist of the H. sapiens and the neandertals
present some derived features that are not present in the one from the
LB1. From these studies the authors came to the conclusion that the
Homo floresiensis is not a pathological Homo sapiens, but
rather a specific human species, different to anything which could be
present in the fossil register of the human species. According to
Tochieri and his colleagues, Homo floresiensis was ramified making
its own evolutionary path before the lineage which derived in the
sapiens and the neandertals from their last common ancestor.
The authors recognized, however, more fossils are hended, above all from
the Homo erectus in broad sense, that is to say, African examples
between 1,8 and Ma. They mainly miss carpian bones 37 of that size. If they could be
found, they would help notoriously either to validate or refute the
hypotheses that the authors have suggested.
Which is the origin of the Homo floresiensis ? The topic is too
open, as it implies many uncertainties. At first its discoverers were
strongly in favour of the H. floresiensis as descendants of the
Homo erectus, which had arrived in what it is nowadays Java and
Sumatra 1,8 million of years ago (as the finds in Modjokerto, Trinil or
Solo show, and according to the datings of the geochronologist Carl
Shiwcher). We have already mentioned Flores was never united to the
continent because it was always isolated by an inlet which acted
(relatively) as a biological barrier. That separation is known as
“Line of Wallace”. The human presence in Flores goes back to
at least more than 800,000 years ago, as Morwood points out, alleging
that is what supports the fact of having found lithic tools in the island
that old. However there are people who question this arguing their
morphology is not from anthropic origin, but due to the action of natural
agents. Though the truth is most of the scientific community tends to
believe the testimony of Morwood and Brown. The question would be then:
How was it possible some humans could navigate through so dangerous
waters 800,000 years ago? Were they able to arrive in Flores by chance?
Anyhow, this fact is part of many mysteries still to be solved in
relation with the human presence in Flores.
Nowadays there are three big hypotheses are considered to explain the
origin of the Homo floresiensis. On the one hand, there is the
possibility they are the descendants of some supposed erectus who
had arrived in Flores at least 800,000 years ago (being then the possible
authors of the tools found in the Depression of Soa), and who had reduced
their body dimensions as a way of adaptation to the scarce resources of
the island. This is the hypothesis the authors of the discovery opted for
the most. Another possibility is that the H. floresiensis already
arrived in the island with a size significantly tiny, maybe due to a
process of dwarfism undertaken in other islands. Nowadays the directors
of the team working in Liang Bua consider this as the most valid
hypothesis. Although, in this case, it is still a mystery the specimen
from which the H. floresiensis had evolved. However, it cannot be
rejected these humans already arrived in the Asian Southeast with body
dimensions extremely tiny before occupying some island. In that case, the
possibility they descended directly from the Homo habilis, or the
Homo georgicus, seems to be quite plausible. Not in vain from the
finds of Dmanisi, in the Caucasus, it has been proved the first humans to
abandon Africa were not the Homo ergaster (that is: the so called
African Homo erectus; or, to be more precise, the African
ancestors of the Asian Homo erectus) but a more archaic human
species and possibly derived from the Homo habilis: los Homo
georgicus 38. More surprising was Milford Wolpof’s
proposal, who suggests the H. floresiensis could descend from the
Australopithecus and that even they could have leave Africa, being
the promoters of an early exodus towards the Asian Southeast. A risky
proposal such as this should be based on empirical proofs with a minimum
of soundness (some fossils which suggest something like this) to be able
to have certain degree of credibility. However, nothing of this has been
found, though Wolpof maintains that it has happens so, but we do not know
how to see it, so fossils assigned up to now first to Meganthropus
and then to a H. erectus should be re-examined considering the new
finds to see if it was possible to assign them to an
Australopithecus. A far too much heterodox proposal and that
before acquiring certain credibility has to see how the possible more
plausible and less revolutionary hypotheses become exhausted.
Nowadays the team who directs the excavation works in Liang Bua consider
the Homo florsiensis as descendant from some kind of hominid
similar to the Homo habilis who had arrived in the Asian
Southeast. Although the fossil remains of African Homo habilis and
Homo floresiensis are separated for more than 9,000 km and by more
than two million of years, the truth is that the cranium of LB1 and of
some H. habilis are very much alike 39.
Anyhow, the truth is the mystery of the origin of H. floresiensis
continues and we cannot even imagine the surprises this question may
bring.
Notes
(1) Cf. P. Brown, M.J.
Morwood, et. al.: A new small-bodied hominin from the late
Pleistocene of Flores, Indonesia; Nature, 431,
28th October, 2004, pp. 1055-1061; y M.J. Morwood, R.G.
Roberts, et. al.: Archaeology and age of a new hominin from
Flores in eastern Indonesia; Nature 431, 28th
October,2005, pp. 1087-1091.
(2) A very small island of
the Indonesian archipelago situated between Java (to the West) and Timor
(to the East), with Australia towards the South and the Celebes and the
Molucas to the North.
(3) There is someone who
has reminded us, not without humour, we should not forget that despite
being called Homo floresiensis the holotype (or paradigmatic
specimen of the clado) is a female; technically known as LB1.
(4) It refers to the 28th
October, 2004.
(5) http://www.portalciencia.net/antroevoflor.html
(6) M.J. Morwood et
al.: Fission-track ages of stone tools and fossils of the east
Indonesian islands of Flores; Nature 392, pp. 173-176, 1998.
And M. J. Morwood et al.: Archaeological and paleontological
research in central Flores, East Indonesia: results of fieldwork,
1997-98; Antiquity 73, 273-286 (1999).
(7) Kyr. means kylia years;
that is: thousands of years.
(8) For a thorough analysis
of the most important aspects related to the discovery of the Homo
floresiensis see Carlos A. Marmelada: Homo floresiensis. El
pequeño gran misterio de la evolución humana; en http://www.unav.es/cryf/homofloresiensis.html,
which is the extract of a conference given on the 19th April, 2005 in
the University Cardenal Herrera of Valencia; also in the web page of the
Consejería de Educación y Cultura del Gobierno de la
Región Autónoma de Murcia (Portal educativo de la Región de Murcia).
See also Carlos A. Marmelada: El pequeño gran hombre de Flores;
Aceprensa service 144/04, 10-11-2004.
(9) In a popular way they
are also called that way in honour of J.R.R. Tolkien and his race of tiny
humans in the Saga of The Lord of the Rings.
(10) Article included in
Larry Barham: Some initial informal reactions to publication of the
discovery of Homo floresiensis and replies from Brown & Morwood;
in Before Farming 2004/4 article 1, pp. 2 and 3. The reply of Brown and
Morwood is in p. 6.
(11) This skeleton was
described by Teuko Jacob in: Some problems pertaining to the racial
History of the Indonesian Region; Utrecht: Drukkerij, Neerlandia,
1967.
(12) We will come back
about it later. See the further note 31.
(13) M. Mirazón
Lahr and R. Foley: Human evolution writ small; Nature,
vol. 431, 28th October, 2004, p. 1043.
(14) M.J. Morwood et
al.: Archaeology and age of a new hominin from Flores in eastern
Indonesia; op. cit., p. 1089.
(15) Opinion given by
Tim Reynolds in Larry Barham: Some initial informal reactions to
publication of the discovery of Homo floresiensis and replies from Brown
& Morwood; in Before Farming 2004/4 article 1, pp. 4 y 5. The
reply is in p. 6.
(16) For more
information regarding the subject see Elizabeth Culotta: Battle erupts
over the ’Hobbit’ bones; Science, Vol. 307, 25th
February, 2005, p. 1179.
(17) See Rex Dalton:
Fossil finders in tug of war over analysis of hobbit bones;
Nature, Vol. 434,
3rd of March, 2005.
(18) We have to thank M.
J. Morwood for his great kindness in providing us with a copy of the
pages of the mentioned diary.
(19) For an analysis of
the state in which the fossils of H. floresiensis were returned to
M. Morwood and colleagues you can see Elizabeth Culotta: Discoverers
charge damage to ’Hobbit’ specimens, Science,
25th of March.
(20) Dean Falk, Charles
Hildebolt, Kira Smith, Mike Morwood, Peter Brown, et al.: The brain of
LB1, Homo floresiensis; Science Express, and Science,
Vol. 308, pp. 242 y ss. Cf. also, Michael Balter: Small but smart?
Flores hominid shows signs of advanced brain; Science 307,
4th March, 2005, pp. 1386-1389. And also Carlos A. Marmelada:
El Hombre de Flores asombra a los científicos, Aceprensa,
Servicio 27/05, 09-03-2005. You can also consult Rex Dalton: Looking
for the ancestors; Nature, Vol 434, 24th March,
2005, pp. 432-434.
(21) Fact calculated
from a virtual reconstruction of the brain using technics of computerized
tomography (TC).
(22) J. Weber, A.
Czarnetzki y C. M. Pusch: Comment on “The brian of LB 1,
Homo floresiensis; Science, Vol 310, 14th October, 2005, p. 236b.
(23) D. Falk et al.:
Response to Comment on “The Brian of LB 1, Homo floresiensis
”; Nature, Vol. 310, 14 October, 2005, p. 236c.
(24) Robert D. Martin
et al.: Comment on “The Brian of LB 1, Homo
floresiensis ”; Science, Vol. 312, 19th
May, 2006, p. 999b.
(25) Known technically
as AMNH 2792ª and which corresponds to a child called Jacob Moegele,
who died at the age of 10 years old in Plattenhardt, Germany. His cranium
capacity was really tiny: 272 cc. The acronym AMNH means American Museum
of Natural History.
(26) Dean Falk et al.:
Response to Comment on “The Brian of LB 1, Homo floresiensis
”; Science, Vol. 312, 19th May, 2006, p. 999b.
(27) M. J. Morwood et
al.: Further evidence for small-bodied hominins from the Late
Pleistocene of Flores, Indonesia; Nature, Vol. 437,
13th October, 2005, pp. 1012-1017. Other articles related with
this issue that may be consulted are Daniel Lieberman: Further fossils
finds from Flores; Nature, Vol 437, 13th October,
2005, pp. 957-958 and Rex Dalton: More evidence for hobbit unearthed
as diggers are refused access to cave; Nature, Vol. 437,
13th October, 2005, pp. 934-935; as well as Elizabeth Culotta:
New ’Hobbits’ bolster species, but origins still a
mystery; Science, Vol. 310, 14th October, pp.
208-209.
(28) Adam Brumm, Mark
Moore, Fachroel Aziz, Michael Morwood, et al.: Early stone technology on
Flores and its implicatios for Homo floresiensis; Nature, Vol. 441, 1st
June, 2006, pp. 624-628. See also Elizabeth Culotta: Tools links
indonesian ’Hobbits’ to earlier Homo ancestor; Science,
Vol. 312, 2nd June, 2006, p. 1239.You could also consult Michael Hopking:
Old tools shed Light on hobbit origins; Nature, Vol. 441, 1st June,
2006, p. 559.
(29) Teuko Jacob, Rodien
P. Soejono, Maciej Henneberg, Allan Thorne, R. B. Eckhardt et al.:
Pygmoid australomelanesian Homo sapiens skeletal remains from
Liang Bua, Flores: Population affinities and pathological
abnormalities; PNAS, Vol. 113, nº 36, 5th September,
2006, 13421-13426.
(30) Jacob et al.:
Pygmoid australomelanesian Homo sapiens skeletal remains from
Liang Bua, Flores: Population affinities and pathological
abnormalities; op. cit., p. 13.422.
(31) See former note 12.
(32) Debbie Argue, Dense
Donlon, Colin Groves, Richard Wright: Homo floresiensis:
Microcephalic, pygmoid, Australopithecus , or Homo ?;
Journal of Human Evolution, 51, 2006, pp. 360-374.
(33) D. Falk, et
al.: Brian shape in human microcephalics and Homo
floresiensis; PNAS, Vol. 107, nº 7, 13th February, 2007,
pp. 2513-2518.
(34) M. Moore and A.
Brumm: Stone artefacts and hominins in island Southeast Asia: New
insights from Flores, eastern Indonesia; Journal of Human Evolution,
Vol. 52, 2007, pp. 85-102.
(35) S. G. Larson: Homo
floresiensis and the evolution of hominin shoulder; Journal of
Human Evolution, 2007, pp. 1-14.
(36) Matthew W. Tocheri,
et al.: The Primitive Wrist of Homo floresiensis and Its
Implications for Hominin Evolution; Science, Vol. 317,
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(37) Scaphoid,
trapezium, trapezoid, etc…
(38) For more
information about the Homo georgicus cif.: Unos fósiles
hallados en el Cáucaso se asignan a una nueva especie humana;
by Carlos A. Marmelada, in Aceprensa service 154/02, 20-11-2002.
(39) Ver al respecto
Mike Morwood y Penny Van Oosterzee: The discovery of the Hobbit. The
scientific breakthrough that changed the face of human history;
Random House, Australia 2007.
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