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Re: Pick one - massive or agile



Wouldn't greater inertia have more of an affect on acceleration than maximum 
speed? 

Jason


--- On Tue, 7/6/10, Heinrich Mallison <heinrich.mallison@googlemail.com> wrote:

> From: Heinrich Mallison <heinrich.mallison@googlemail.com>
> Subject: Re: Pick one - massive or agile
> To: "Erik Boehm" <erikboehm07@yahoo.com>
> Cc: dinosaur@usc.edu
> Date: Tuesday, July 6, 2010, 10:11 AM
> That is true - but not what I was
> talking about. I was referring to
> this paragraph
> 
> >>Large animals may cope with these relatively long
> delays by simply moving slowly,
> >>explaining at least in part the low maximum speeds
> of large mammals (Garland 1983;
> >>Hutchinson et al. 2006) and providing further
> evidence for the idea that dinosaurs could
> >>not be both massive and agile (Hutchinson &
> Garcia 2002).
> 
> this is, as I said, utter BS! Reaction times are not that
> much larger
> that large dinosaurs could not run at 60 mph! Clearly,
> locomotion is
> much more influenced by inertia. Slow maximum speeds are,
> I'd guess,
> 99% force/inertia and 1% reaction time limited.
> 
> So whatever the finding on reaction times is, actually
> suggesting they
> have a profound influence on locomotion is nothing but
> palaeofantasy.
> 
> Regards,
> Heinrich
> 
> 
> On Tue, Jul 6, 2010 at 3:45 PM, Erik Boehm <erikboehm07@yahoo.com>
> wrote:
> > Inertia has nothing to do with reaction times.
> > It can explain slow movement speeds, but not response
> delays
> >
> >> It takes an elephant much longer to notice a fly
> >
> >
> >
> > --- On Mon, 7/5/10, Heinrich Mallison <heinrich.mallison@googlemail.com>
> wrote:
> >
> >> From: Heinrich Mallison <heinrich.mallison@googlemail.com>
> >> Subject: Re: Pick one - massive or agile
> >> To: dinosaur@usc.edu
> >> Date: Monday, July 5, 2010, 11:22 PM
> >> Bah, nonsense! The travel time
> >> increase for nervous signals is utterly
> >> irrelevant compared to the increase in inertia.
> That's
> >> what's slowing
> >> huge animals down!
> >>
> >> Heinrich
> >>
> >> On Tue, Jul 6, 2010 at 4:54 AM, Richard W. Travsky
> <rtravsky@uwyo.edu>
> >> wrote:
> >> >
> >> > http://www.nytimes.com/2010/07/06/science/06obelephan.html
> >> >
> >> > It takes an elephant much longer to notice a
> fly and
> >> flick it away than it
> >> > takes a shrew, and the reason is not that
> the
> >> elephants great brain is too
> >> > busy with philosophy, or that it simply does
> not
> >> concern itself with flies.
> >> >
> >> > Its a matter of round-trip travel time - in
> the
> >> nervous system. The trip
> >> > from the elephants skin to the brain and back
> again to
> >> the muscles to flick
> >> > the tail is 100 times as long as the same
> trip in a
> >> shrew, according to a
> >> > new study published in the Proceedings of the
> Royal
> >> Society B.
> >> >
> >> > The nervous system acts like an information
> >> superhighway, sending messages
> >> > back and forth from the brain throughout the
> body. The
> >> bigger the animal,
> >> > the greater the distance traveled.
> >> >
> >> > Nerves have a maximum speed limit of about
> 180 feet
> >> per second, said Maxwell
> >> > Donelan, the studys lead author.
> >> >
> >> > It makes sense that in a large animal, like
> an
> >> elephant, messages have a
> >> > longer way to travel, he said.
> >> > ...
> >> >
> >> >
> >> > http://rspb.royalsocietypublishing.org/content/early/2010/06/24/rspb.2010.0898.full
> >> > ...
> >> > As a consequence, larger animals are burdened
> with
> >> relatively long
> >> > physiological delays, which may have broad
> >> implications for their behaviour,
> >> > ecology and evolution, including constraining
> agility
> >> and requiring
> >> > prediction to help control movements. ...
> >> > Large animals may cope with these relatively
> long
> >> delays by simply moving
> >> > slowly, explaining at least in part the low
> maximum
> >> speeds of large mammals
> >> > (Garland 1983; Hutchinson et al. 2006) and
> providing
> >> further evidence for
> >> > the idea that dinosaurs could not be both
> massive and
> >> agile (Hutchinson &
> >> > Garcia 2002).
> >> > ...
> >> >
> >>
> >
> >
> >
> >
>