You just knew this kind of thing was coming, didn't you?
Because if man is an endemic evil to the planet, why not man's best friend?
And since keeping even a medium-sized canine as a pet "damages" the environment as much as driving a gas-guzzling SUV (according to the authors of Time to Eat the Dog: The Real Guide to Sustainable Living), you've got to give up Fido and buy a goldfish or canary instead.
Chickens, rabbits and goats? Well, they're okay too say the authors...but only if you eat them.