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First off, can I suggest that people stop hypothesising about imaginary
dinosaurs. This list is supposed to be for dinosaur science, not science
fiction. Please keep in mind how painful it can be when wading
through 200-odd emails all on the same subject, especially when
several of the list-members involved insist on repeating substantial text
from previous list emails and then add little text of their own.
For those interested, some of my thoughts on hypothetical dinosaurs
The first one is pretty dated (it was 1995!).
On early stegosaur evolution and the evolution of their feet, George
> I'm not talking about what stegosaurs >became<, I'm talking about
> their Triassic to Early Jurassic forms, as yet undiscovered, which
> (even if they were early thyreophorans, which I am not convinced that
> they were) were still good cursors somewhat resembling Scutellosaurus.
> Otherwise, explain why graviportal forms would lose digit >and<
> metatarsal I in the hind foot. Didn't happen in any other graviportal
> dinosaur group, why in stegosaurs?
One _Stegosaurus_ specimen retains a vestige of a fourth metatarsal.
George has argued that reappearance of a lost digit is effectively
impossible so.. does this indicate that metatarsal I was retained within
Stegosauria right up to the ancestor of _Stegosaurus_? I suppose the
alternative is that this individual was teratological.
It is also worth noting that Le Loeuff et al. (1999) described a possible
stegosaur track from the Hettangian of France. The hindfoot track had
three main digits and an indistinct impression of a first. However, the
phalanges appear to have been very short in this specimen: thus,
phalangeal shortening (indicative of graviportality) appears to have
preceded digit reduction (indicative of cursoriality). *IF* this track
does belong to an early stegosaur, it suggests that the animals became
heavyweights >before< they evolved the fully reduced tridactyl foot of
advanced stegosaurs (rather than vice versa as per George: reduced
foot first for cursoriality, then graviportal foot as advanced stegosaurs
Le Loeuff, J., Lockley, M., Meyer, C. and Petit, J-P. 1999. Discovery
of a thyreophoran trackway in the Hettangian of central France. _C. R.
Acad. Sci. Paris_ 328: 215-9.
As someone who thinks the evidence for a monophyletic Thyreophora
is pretty good, I would suggest that a quadrupedal ancestry for
stegosaurs is more likely than a bipedal, cursorial ancestry.
SOME THOUGHTS ON PALAEONTOLOGY IN THE MEDIA
Finally, WRT the treatment in the media of palaeontological issues, it
is an artefact of western culture that science seemingly has to be
presented in a, for example, WWD 'mock nature show' format. There is
plenty of scope for showing real bones, the people that work on them,
reconstructions, animatronics etc without dissolving into fantastic
speculation and antiscience: it's just that TV production people aren't
as turned on by this, often because they themselves come from a very
A similar problem is afflicting documentaries on live animals: more
and more series of the so-called 'extreme natural history' genre are
appearing. While some of the characters involved are qualified
zoologists who do technical research and emphasise the importance of
conservation, they frequently abuse the animals they are handling
(Mark O'Shea, for example, is often shown holding live animals in his
mouth). There was never anything wrong with natural history TV
programmes in the past: they got good ratings and people liked
watching them. But now that a new element of sex and rock'n'roll has
been added, TV people are adopting this as the template they MUST
I've worked with satellite TV stations, Channel 4, BBC and other
companies within recent years: let me say that it's been the satellite
channels (whose biggest audiences are in India and SE Asia) that have
been most willing to portray science in an honest way without a climb-
down to present things in the most sensationalistic manner possible.
I think it was Albert Einstein who said "Everything should be made as
simple as possible, but no simpler".
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