Can't speak for ferrets - as I have had just a few, total 4 (albaio,
silver, chocolate, sable), but two professional dog trainers have told me
that the black labs are the easiest to train and are smarter, the chocolate
ones are the stupid ones and the yellow labs are stubborn and question what
you ask of them.
 
Cats - my small black cat was really sweet, smart and the ambassador (she
died in '97 as the age of 20, and her half sister, Geneive died the same
year), her half sister, a tortie (calico with black background, calico has
white background) was a fat, fraidy cat.... my calicos - Dixie and Sweetie
were really nice cats, most yellow (marmalade) cats are just plumb CRAZY!
Brown tabbies are usually nice lap cats.  Current cats are two grays, they
hate each other!  They both try to play boss cat and Gray boy knows he is
the boss, Ruby cat thinks she is the boss... you get the idea.
 
Nan and SuperSnooper
[Posted in FML issue 3465]