testability

[Ralph Chapman <MNHAD002@SIVM.SI.EDU>]

I think the mimicry thing is indeed testable. You have to do an awful lot
of work to do it, but it can be done. We can most probably get a feel for
what the theropod visual system is capable of by doing a detailed analysis
of known visual systems and superimposing the patterns on reasonable
phylogenetic reconstructions (e.g., cladograms). There are whole series of
steps that can be followed to check if the club is a good mimic within this
context. Many discussions have occurred within the evolutionary literature
on Rudwickian paradigms and other approaches that allow researchers to
deduce whether a mimic explanation is reasonable as one or one of a combina-
tion of answers. It would include tail movement reconstructions, looking
into the developmental origin of the club itself (as best as we can). If
just a mimic, why isn't it hollow? The answer may be that it really is
(I think not), or it isn't because its developmentally easier to make
a solid club, even if it costs more energy to have it there, or it isn't
because it wasn't a mimic device. I cannot stress enough the potential
power available to the approaches available to scientists - making it
possible to do more than just tell stories. They are strong enough
that we can even do lots within our biased historical record.

The problem with Bakker's theories on disease et al. knocking off the
dinos is that he's never gotten around to doing what he needs to to
provide these clever testable hypotheses. It's a fun story, but even
the plague and the mass diseases on this continent never really came
that close to even killing off our one species, let alone a whole host
of genera. Bakker will just have to start doing science again and get
out of the publicity field if he ever is going to promote such a
hypothesis and get it considered all that seriously by other
paleontologists. I wish he would - he has a clever brain and lots of
dino knowledge which, IMHO is mostly going to waste compared to what
he could be doing. We have too many other clever paleontologists that
we need to pay attention to who are willing to go this extra step
toward quantification.

Sorry, I'll get off my soap box now.   Ralph Chapman, NMNH