Nell,
 
You may want to rethink the "how high do ferrets jump" idea.  A study was
done on ferret intelligence and it was found that they have the same
intelligence as a small primate... which makes them very smart.  I have
seen our ferrets work together to get something done.  They've dragged
things over to stand on.  They have used each other as ladders to get
over things or used each other as spring boards.  They have tricked us
in to doing things to "help their cause", whatever that may be at the
time.  A few ferrets have distracted us while the rest grabbed the treats
and ran, then they all meet up to split up the booty.  When you think
you've figured a way to keep them in or off something you've only given
them a new and momentary challenge to learn from.  My husband and I are
continuing to work to stay one step ahead of them in their cleverness.
These are truly amazing little guys.  If you want to stay active and keep
your mind sharp--be a ferret owner.
 
Nancy
[Posted in FML issue 4888]