Good information, Sue. Thanks.
I'm getting anecdotal information that makes a lot of sense from the various postings and it seems 25 degrees could be modelled as the maximum slope for effortless (or "low friction") travel, then higher "friction" from there to the point beyond which the animals will simply choose another route (40 degrees?). This helps a lot.
Any other comments/offerings?
Cheers all,
Ariane
Ariane Burke, Prof. Titulaire
Dept. d'anthropologie
Université de Montréal
C.P. 6128, succursale Centre-Ville
Montréal, QC
Canada
H3C 3J7
Tel. (514) 343-6574
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From: Analysis of animal remains from archaeological sites on behalf of Sue Millard
Sent: Sat 8/12/2006 4:33 PM
To: [log in to unmask]
Subject: Re: [ZOOARCH] slope
I live in Cumbria where we have extensive commons on which ponies
graze. These ponies can run up to 2,600 feet on the slopes of the
Pennines. They tend not to try slopes steeper than 25% unless it is
easy to traverse (and so they can make the gradient less by zig-
zagging) AND they know there is somewhere ahead that is less steep
where they can turn round to come back or can take a less steep way
back down. They will go/graze up slopes of 25% but you don't often
see them coming down the same places!
Grass tends not to grow well on these higher slopes as on the the
steeper gradients the rocks/stones/screes/grits are unstable and
grass doesn't get a good permanent root hold. While ponies will eat
all kinds of herbage and will often go to some lengths to get to
unusual ones they like, they do prefer grass as their staple diet. So
for several reasons they tend not to attempt the steeper slopes.
Sue Millard MSc, BEd
Web minion for Fell Pony and Countryside Museums
http://www.fellpony.f9.co.uk/
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