[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

The Mystery of the Jurassic



I just watched "The Mystery of the Jurassic" on the ABC here in
Australia on wednesday night. The mystery is why I bothered to watch it
all the way to the end. Prepare yourself for rampant sarcasm...

What a load of clap-trap! (Although I had another "c" word in mind). If
you took all the recycled WWD footage out of it, the one hour program
would have gone for all of 15-20 minutes. 

My favourite part was when the voice-over guy was waxing lyrical with
the usual hyperbole. He finally came to the end of his dramatic
statement, with the words "... the Late Jurassic", accompanied by a
crescendo in the equally dramatic music, and we are shown dramatic
footage of a pair of Tyrannosaurs fighting (in a dramatic fashion).

A dense layer of fish fossils in Middle Jurassic S.American layers shows
them in contorted positions. Proof that they died horrible agonising
deaths due to wide-spread volcanic fall-out? Or just an isolated
fish-kill event where the water hole dried up, causing the drying fish
carcasses to twist about? I immediately thought of the latter (remember
how contorted dinosaur fossils were once used as proof of poisoning - a
theory that has since been abandonded?). However the voice-over guy
pushed the first scenario for its full dramatic effect. What a surprise
when he then told us that the theory wasn't backed up by other evidence!

The whole premise of the program was whether or not dinosaurs became
more varied after the break-up of Pangaea. A palaeontologist shows us a
single partial theropod skeleton from before the break-up. It was
vaguely Allosaur-like. Proof that when S.America was still joined to
N.America, dinosaurs were more conservative across the globe!

Then a mammal specialist looks at a post-break-up mammal jaw from
S.America. It has a small groove in a certain part of the lower jaw that
a mammal jaw of equivalent age from N.America lacked. Wow! Post-Pangaea
mammals were completely different on the two continents! Rapid
evolutionary divergence at work!

Another palaeontologist shows us a sauropod femur from Post-Pangaea
S.America, and compares it with a sauropod femur from N.America of about
the same age. The S.American specimen has a slight bulge near the top of
the femur that the N.American animal lacked. Yet more evidence of the
explosion of variability that occured after the break-up of Pangaea!

Not once did anyone suggest that the apparent lack of variability in
dinosaur forms during Panagean times was due to a smaller sample size of
fossils. Isn't it amazing how, as fossil layers become younger, there
seem to be more dinosaurs? Surely it couldn't be that the older material
is destroyed by geological forces, or that younger deposits tend to be
closer to the surface...


Ouch! My sarcasm gland has swollen from over-use! And the finger I use
to type exclamation marks is sore!

-- 
________________________________________________________________

Dann Pigdon                   Australian Dinosaurs:
GIS / Archaeologist         http://www.geocities.com/dannsdinosaurs
Melbourne, Australia        http://www.alphalink.com.au/~dannj/
________________________________________________________________