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Re: CRANIAL-CAUDAL vs ANTERO-POSTERIOR



philidor11 wrote:
> 
> <On the related subject of metric vs. imperial, given that we all agree
> (don't we?) that metric _has_ to be The Right Thing...>
> 
> Well, no, I think it is A Choice.  There is no intrinsic superiority of a
> meter compared to a yard or a foot.  In fact, I'm wondering why hands as a
> measurement apply only to horses these days and why rods haven't stayed in
> use right along with acres.

It is a choice, but the metric system, as a whole, does have intrinsic
advantages over the Imperial (as it is known in the UK) or British (as
it is known in the US) system.  The two most obvious advantages are:

scaling - everything goes in factors of 10 or powers thereof:10
millimetres in a centimetre, 10 centimetres in a decimetre, 10
decimetres in a metre and so on;

relatedness - a tonne of water (1000 kilograms) occupies a cubic metre
(and given that most tetrapods have a density pretty close to 1, a tonne
of Apatosaurus would occupy a cubic metre); starting with the kilogram,
the metre and the second, you can get almost any other unit without
needing to do any multiplication (just keep track of the zeros) - try
that with foot-pounds, acres, miles, thous, ounces etc;

less obvious, and admittedly coincidental:

acceleration under gravity is close to 10 metres per second per second,
which makes it easy to calculate how long it would take for a branch
dropped by a greedy Brachiosaurus to land on its toes. 

cheers
Stephen