hello all,
Thanks very much to all those that aided me in tracking down Komodo
dragon and water monitor lizard skeletons.
Dale requested an explanation of the archaeological significance of the
Komodo Dragon. Sorry Dale, that this has taken a while, but i've been
busy. I sent this to everybody, in case there are others interested
other than Dale.
I'm currently employed studying a faunal assemblage from the Great Niah
Cave system, which is situated in a limestone outcrop, in Sarawak,
Malaysian Borneo. The site dates from between approx. 45,000 BP and 1100
- 1300 AD. During recent excavations, and associated with human refuse
(dating between 10,000 BP and 8,000BP) that includes several primate
taxa, chelonids, pig, snakes and various other interesting vertebrates,
we recovered several normal sized, and one extremely large varanid
vertebrae. In addition, investigations of another cave site in the
system produced a small assemblage of vertebrate remains (some of which
are calcined), probably of late Pleistocene or early Holocene date, that
included Orangutan, monkey, snake, pig and two very large varanid
vertebrae.
As part of my background reading i'd come across an interesting paper by
Hooijer, who had discovered within the middle/ late Pleistocene Dubois
collection from Java two extremely large varanid vertebrae that he
tentatively suggested were possibly the remains of V. komodoensis.
However, the main focus of the paper was on two varanid vertebrae (one
thoracic and one caudal) recovered from Timor. Hooijer also tentatively
suggested that these vertebrae could also be a sub-species of V.
komodoensis, or the remains of another extinct island species.
If correct, this would suggest that the Komodo dragon was not restricted
to the Islands of Flores, Komodo and Rinca during the Pleistocene, but
was much more widely distributed. In addition, Java makes up part of the
Sunda shelf, that during the Pleistocene was above sea level, and joined
Java to Sumatra, Borneo and mainland Malaysia (Sundaland).
So the intial question concerning the Niah material was, were the
vertebrae of late Pleistocene/ Early Holocene date from Niah, those of
the water monitor or something larger, either a now extinct species of
varanid, or the komodo dragon.
So myself, and a collaegue visited Naturalis, in Leiden as part of our
research, both to locate parts of the Niah cave assemblage (Hooijer had
also worked on) and to try and identify the three vertebrae from the two
cave sites at Niah.
As it turns out, the thoracic vertebrae from Niah are those, probably of
a large water monitor (V. salvator). However, during the visit, Dr Jon
de Vos (head curator of Paleontology) hinted that he was 'unconvinced'
by some of the identifications of reptile bones in the Dubois
collection, and could we confirm that those remains classified as
crocodile, were in fact crocodile. Interestingly, several vertebrae had
been mis-identified. They included one or two large Pythonid vertebrae,
but more significantly several thoracic and sacral vertebrae of an
extremely large varanid.
The caudal vertebra from Timor appeared to be considerably larger than
those of the modern comparative examples of the Komodo dragon. In
addition, Jon de Vos presented us with a third vertebra from Timor, that
Hooijer was unable to examine. It is an enormous varanid sacral
vertebra, that again appears to be considerably larger, certainly, than
any recently deceased Komodo dragon.
As a result, we are hoping to get in touch with some collaegues from
Australia and undertake some biometrical and morphological analyses of
remains of Megalania.
Thus, from what started out as a simple zooarchaeological question 'What
taxa are represented within this faunal assemblage', the study has moved
on to trying to differentiate morphological and biometrical variation in
the vertebrae of large varanid taxa in Southeast Asia and Australasia.
the results of suich studies are important for identifying the former
distributions of taxa, and this can have obvious implications for
biological conservation issues. For example, it has, in the past been
argued by ecologists that the Komodo dragon evolved gigantism as an
island species. Is this true? or was the Komodo dragon formerly much
more widely distributed (possibly across parts of Sundaland), and those
few individuals now inhabiting the Indonesian islands are but relict
populations. Did Timor have its own, now extinct population of giant
varanids, or did the distribution of megalania extend beyond the
Australian continent?
These are a couple of the questions that we hope to address. To do this
we are trying to collate as much data on varanid comparatives as
possible and build up a dataset that will be statistically large enough
to come up with some reliable results, and hopefully differentiate the
vertebrae of large varanid taxa. We cannot differentiate the varanids on
size alone, as they just increase in size as they age. thus, how do you
separate a small komodo vertebra from those of a large member of the
three extant montor lizard species that inhabit Borneo. The trouble is
finding enough large southeast Asian monitor lizard and komodo dragon
skeletons.
Future studies, might yet uncover further large varanid vertebrae in
Borneo, and as it appears that the former distributions of monitor
lizard taxa is still unclear, this study might just help to identify
analysts to identify the vertebrae of Southeast Asian monitor lizards.
Sorry about the length of this e-mail but it wasn't an easy question to
answer in a few words.
Phil
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