A medium-sized dog has twice the carbon footprint as a Toyota Land Cruiser, according to a New Zealand study conducted by environmentalists. The comparison is in terms of land: how much it takes to feed the dog versus feeding the truck. I assume it is an alcohol-powered truck. I don’t know if the study considered the packaging the food came in. It did not concern the emissions of the truck, or, indeed, of the dog.

The truck has some points over the dog. The truck’s emissions have declined in the past 20 years. Dog emissions have held constant, though their public effects have been moderated by their owners following behind them with little plastic bags. People didn’t do that 25 years ago--at least, not in Seattle.

The study also pegged the environmental evil of cats. It found, through scientific calculation, that takes 0.84 hectares to feed an average dog, and 0.15 for a cat. That makes a dog worth between five and six cats—or about five Volkswagen Golfs. This is flattering to the dog, no doubt, but not likely to be accepted by the cat. And don’t try it on a VW dealer.