It claims that the carbon footprint left by domesticated animals is out of proportion to the size of their paws.
A medium-sized dog has the same impact as a Toyota Land Cruiser driven 6,000 miles a year, while a cat is equivalent to a Volkswagen Golf.
At the same time a pair of hamsters do the same damage as running a plasma television, suggests the book Time to Eat the Dog: The Real Guide to Sustainable Living.