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Re: Novas, Age of Dinos in S.A., pg 203 figure D

Impact sounds are produced not by force (weight) but by energy -- the
sudden deceleration of the foot hitting the ground hard, with kinetic
energy transformed to (in part) sound energy.  Animals just don't do
that when they're walking (though obviously when running it's a
different matter).  Next time you see a herd of cattle walking along a
dirt track, listen for the hooves.  They're not loud.

2009/10/13 Jaime Headden <qi_leong@hotmail.com>:
>  <958fcd230910130636l1b3c5d22n96e325fb76a126b9@mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
> Content-Transfer-Encoding: quoted-printable
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> Mike Taylor wrote:
> <Common misconception=2C enshrined in names like Seismosaurus ("Earth-shake=
> r lizard") and indeed Sauroposeidon and Xenoposeidon (Poseidon being the Gr=
> eek god of. among other things=2C earthquakes). I don't know of ANY animal =
> that makes a loud noise in normal locomotion -- elephants=2C for example=2C=
>  walk very quietly -- and I can't think of any reason to expect that saurop=
> ods would have been any different. A loud noise means a strong and sudden i=
> mpact=2C which is NOT what you want to do to your feet if you weigh 50 tonn=
> es.>
> Mike=2C
> =A0 I'm mildly interested in this line of thinking. Would you care to specu=
> late on why or how a multi-tonne animal can move quietly despite the potent=
> ial force it can generate with its movement?=A0 I have never been clear on =
> the mitigating properties of the organism (presumably=2C the fleshy pads he=
> lp=2C but we are talking about animals with limbs [much less the whole anim=
> al] much closer to the weight of elephants here).=A0 As an analogue=2C the =
> movement of a multi-tonne bus (around 30=2C I beleive) right outside my apa=
> rtment (second storey) causes the building to quaver=2C although I also ass=
> ume this is part of its disruptive airflow pulling behind it=3B this would =
> also be analogous to not just a step impact but also a movement causing air=
>  disruption and wake.
> =A0 Cheers=2C
> Jaime A. Headden
> "Innocent=2C unbiased observation is a myth." --- P.B. Medawar (1969)
> "Human beings=2C who are almost unique in having the ability to learn from =
> the experience of others=2C are also remarkable for their apparent disincli=
> nation to do so." --- Douglas Adams (Last Chance to See)
> "Ever since man first left his cave and met a stranger with a different lan=
> guage and a new way of looking at things=2C the human race has had a dream:=
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>                                          =0A=
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