"Rat terrier" isn't considered a breed but a "type" by the AKC because the bloodline contains damn near everything but stegosaurus, but they can be wonderful little dogs. Mine is a middle-aged rescue dog that adopted me two years ago at our animal control shelter. Like most terriers he's hardheaded and very strong for his fourteen-pound weight--they were bred to go into holes in the ground and pull out ******-off animals backward.
Moose has two speeds, Fast Forward and Off. He hunts primarily by scent, and his nose is always working, but he loves to chase squirrels. If I had gotten him as a pup, when I was still able to hunt, I think he might have made a good squirrel dog and maybe heavy-cover rabbit dog.
He's a very loving, happy little guy. Just has a mind of his own when he's on a scent.
"Don't let macho be your epitaph."