I’m so out of touch I didn’t even know that some people are claiming that driving an SUV is better for the environment than having a dog. Thanks to Tyler Cowen, now I do. (And those people aren’t even named Levitt and Dubner!) Thanks to Cowen and Clark Williams-Derry, I also know that the claim is nonsense based on wildly wrong assumptions.
One of the many sub-issues is how to account for the meat that dogs eat. One of the original claims (summarized here) is that dogs’ diets require a large amount of land to grow all the corn to feed all the cows who presumably end up in pet food. Williams-Derry points out that the meat in pet food is generally meat that humans do not eat, and hence demand from pets only has a small impact on the market-clearing quantity in the market for cows. Williams-Derry and Cowen both point out that this impact is not zero, since the existence of pet food suppliers as buyers of meat scraps increases the short-term profits from cows, and hence more cows will be supplied. But it’s a lot smaller than if you were growing entirely different cows for pet consumption than for human consumption.
I’ve been curious about this sort of thing because I am more or less a vegetarian (with one significant loophole) who continues to wear leather belts and shoes, which presents a similar issue. However, I’ve never claimed that being a vegetarian is necessarily logically consistent.
But there’s another sub-issue I’m interested in, which is what your alternatives are. For most people who drive SUVs, there is a reasonable alternative that gets higher gas mileage. What’s the reasonable alternative to a dog? A goldfish? Giving up a dog means having nothing. Giving up an Escalade means having a Subaru wagon or a Honda CR-V, which gets significantly higher gas mileage.
One of Cowen’s commenters points out that pets probably have environmentally-friendly externalities. I’m a great example of that; I am (largely) a vegetarian because of my dog, and the lifetime reduction in my meat consumption would pay for the ecological footprints of many dogs. (Especially if they were like my dog, who primarily ate vegetarian dog food.)
Finally, if you’re getting a dog from a shelter (which you should), the dog was already there; it’s not like you created a new energy-hogging mouth to feed. Should we simply be killing dogs because of their ecological footprints, or should we be adopting them? Unless you’re in favor of killing them, your decision to adopt a dog does not have any impact on the environment. Demand to adopt dogs from shelters does not affect supply of new puppies by breeders in any way that I can see. (I don’t think demand for puppies goes up because buyers know they can unload their dogs on the secondary “shelter market” when they tire of them.) The same cannot be said of buying a new SUV.
By James Kwak