Dinosaur Dreaming 2006 Field Report

[Dann Pigdon <dannj@alphalink.com.au>]

DINOSAUR DREAMING 2006 FIELD REPORT
(EK, South-eastern Australia)

Map: http://www.alphalink.com.au/~dannj/vicsites.gif

This year a partial hypsilophodont skeleton - consisting of a left pes,
partial tibia and fibula, and most of the tail - was discovered by Mike
Cleeland and George Caspar at a site called Eric the Red (after a nearby
shipwreck) near Dinosaur Cove . It will be compared to two other partial
hypsie skeletons previously found at Dinosaur Cove itself (which I
believe include the specimen with the osteomyelitic tibia). It now seems
likely that the two from Dinosaur Cove are specimens of Leaellynasaura.
The new site will be investigated to see if it warrants more systematic
excavation.

Meanwhile, a few hundred kilometres to the east: This year was the 13th
excavation season at the Flat Rocks site, and new fossil deposits just
keep being discovered. Around 800 specimens were catalogued this year
(bringing the total to around 11,000), including four more mammal jaws,
and what might be some actual non-jaw-related mammalian cranial material
(gasp!). One of the mammal jaws is so tiny that it might be a contended
for the smallest mammal that ever lived. The teeth are not much more
than a millimetre in length. Other remains include the ever-present
Hypsie femora, and various dinosaur teeth (including another ankylosaur
tooth).

It's not just bones that are showing up now: the palaeo-ichnologist Dr
Anthony Martin (Emory University, Atlanta) visited the site and
identified various dinosaur footprints and crustacean burrows that had
gone unrecognised all this time. It's amazing what you can find once you
actually know what to look for. The Early Cretaceous crustacean burrows
are apparently the oldest known from Gondwana so far.

After the official field season ended, the ever intrepid Mike Cleeland
took his students to nearby Cape Paterson (where the first Australian
dinosaur bone was found and described 100 years ago) for a hands-on
geology lesson. He wound up finding a turtle skull that may turn out to
be the great-grandaddy of the giant horned Meiolaniids. It's currently
being studied by Dr Eugene Gaffney at the AMNH.

Road works during the 1960s lead to the discovery of the famous
Koonwarra deposits, so when recent road cuttings were dug near Bena in
South Gippsland, a Monash University student who lived in the area
decided to do a bit of exploring on his own. The results are the first
inland dinosaur fossils found in Gippsland (all of the other sites are
on the coast, and Koonwarra yielded 'only' fish, crustaceans, worms and
various insects - if you don't count the isolated feathers). Hopefully
good relationships between Vic Roads and palaeontologists will see more
material coming to light in the future.

The ?Multituberculate tooth found last year (approx. 5mm wide) has been
studied further, and was found to have at least three features not seen
on any other Multi tooth. It either represents a really weird Multi, or
an entirely new group of mammals. I wonder how it will compare to the
recent (but much younger) New Zealand material?

During 2006 Dr Tom Rich spent a month at the Smithsonian Institute,
attempting to identify about 100 mystery specimens from previous field
seasons. Around half were found to be from hypsies (no surprise there),
while the other half were from small theropods. Based on femora alone,
it had always been assumed that the hypsies far outnumbered the small
theropods.

One of the specimens identified by Dr Rich turned out to shatter a
well-loved hypothesis. None of the older Strzelecki deposits (which
include Flat Rocks) had ever yielded any croc remains, but lots of
labyrinthodonts. The slightly younger Otway Group (which includes
Dinosaur Cove) had lots of croc bits and pieces, but no laby's. The
theory went that the colder Strzelecki conditions kept crocs from
getting that far south, allowing the laby's to live in peace. Once the
climate warmed up a bit, crocs made it further south and the laby's went
bye-bye. With the discovery of a croc tooth from Flat Rocks, it turns
out that crocs and temnospondyls were living together at about the same
time - both of them it seems tolerating the cold conditions equally
well.

Finally, never let it be said that Australians can't improvise. When a
small fragile dinosaur toe bone was discovered, it was feared that
cutting around it with the rock saw to extract it might damage the
specimen. Several mouthfulls of chewing gum (provided by eager
volunteers) and the lid of a film canister proved to do the trick
though, protecting the fossil while the rock saw did its gruesome
business.

http://www.earth.monash.edu.au/dinodream/

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Dann Pigdon
GIS / Archaeologist         http://www.geocities.com/dannsdinosaurs
Melbourne, Australia        http://heretichides.soffiles.com
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