[QUOTE=Chronos]
Dogs being considered “male” is easy. The first domesticated dogs were used for hunting, a male-dominated activity, and even the non-hunting jobs dogs get tend to be male-associated activities.
[/QUOTE]
This is an excellent point, and probably goes a long way to answering the question.
I’ve wondered about this for a long time. In fact, I have a distant, perhaps imagined, memory of being in pre-school and whatever the equivalent of the old Dick-and-Jane was that we used had a picture of a boy with a dog and a girl with a cat. Being, at the time, of an age when gender roles first become noticed, I remember feeling vaguely uneasy that my own preference, cats, was associated with the girl.
In fact, in the actual Dick and Jane books, Dick had Spot, the dog, for a pet. Didn’t Jane have a cat?
Despite the fact that I remember wondering about this as a small child, I don’t think I’ve ever put the question into words, or even been sure I was observing a real phenomenon. When I saw the question posted, I immediately knew what was meant, but I was a bit surprised to see that someone else had noticed it.
BTW, it is perhaps worth noting that although dogs are almost always presumed male, there is one exception: the poodle. Not only are poodles seen as female, depicting a dog as a poodle is shorthand in almost every animal comic-strip or cartoon for showing a female dog.
Also, although cats are presumed to be female in many contexts, “tomcatting” is used to describe prototypically male behavior. And although men are often called “dogs” (either negatively or positively) it is far more common to hear a woman called “bitch” (always negatively).