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Re: Bakker lecture

>Robert Bakker was down here today in SF for a lecture and book signing.

I'll be hearing him in Toronto on the 28th, but I can see already why he
frustrates people!

 He spent a lot
>of time pointing out similarities with modern birds.  The following 
>are interesting tidbits from the lecture:
>       - Bakker insists that "Brontosaurus" is the correct name, and
>         that "Apatasaurus" is wrong.

I have seen his arguments on this - unfortunately, they seem to ignore the
ICZN.  Let him propose it as a "nomen conservandum" or whatever they call it
- or is this not possible?

>       - Presented lots of data showing that an animal's top speed
>         is 10x its walking/cruising speed:
>                               Cruise Speed    Top Speed
>                               ------------    ---------
>         Dimetrodon            1 mph           10 mph
>         Elephant              2 mph           20 mph
>         Polar Bear/Rhino      3 mph           30 mph
>         Based on footprints, T.rex walked at 4.5 mph --> ergo, top speed
>         is 45 mph (!)

Whoa there, folks.  (a) who has timed a Dimetrodon lately? (b) mammals ain't
dinos.  (c) elephant's, rhinos and polar bears ain't bipeds.  (c) can every
animal that walks at 3 mph run at 30 mph?

 T.rex also had several large bird-like air sacs --
>         implying that T.rex was specifically well adapted for high
>         respiration needed to run fast.  Not to mention that it could
>         probably have survived at 36,000 feet :-)

Shouldn't that be "T. rex MAY HAVE HAD air sacs"?  Did he really say
unequivocally that they had them?
>       - showed that most of the weight and strength of sauropods is near
>         the hind legs and the base of the tail.  The front part of the
>         body and neck were very light and filled with air sacs.  This
>         makes it *very* easy for it to rear up on the hind legs.

I buy the first part, which makes sense to me - but again, air sacs don't
fossilize, folks.  I am quite prepared to believe that dinos may have had
them and that bone pneumatization is suggestive of their presence, but is
there any reasonto go further?
>       - In arguing for colorful dinosaurs, he made the generalization that
>         animals that:
>               1. have color vision and,
>               2. have daytime courtship
>         are likely to be brightly colored.  I was going to point out
>         to him that humans meet both criteria and yet are rather drab
>         colored :-)

As are many birds.  I am more inclined to think, with no evidence
whatsoever, that dinos may have had colourful parts of their bodies (look at
a cassowary, for example, which seems to be the model for most Oviraptor
reconstructions these days).  A day-glo Ultrasaurus does seem like a
stretch, though...
>He actually covered a lot of ground in that lecture.  In the Q&A at the
>end someone asked the extinction question.  Bakker reiterated his disease
>theory, and pointed out that some very delicate land animals survived,
>so it could not have been the meteor that caused it.

Ronald I. Orenstein                           Phone: (905) 820-7886 (home)
International Wildlife Coalition              Fax/Modem: (905) 569-0116 (home)
Home: 1825 Shady Creek Court                  Messages: (416) 368-4661
Mississauga, Ontario, Canada L5L 3W2          Internet: ornstn@inforamp.net
Office: 130 Adelaide Street W., Suite 1940    
Toronto, Ontario Canada M5H 3P5