Go Figure! The Mathematics of Dietary Death

Computing the cost of plant vs. flesh food production in animals’ lives

Anyone who’s been vegan for any length of time has heard the dizzying array of specious arguments for why people are supposedly meant to eat meat, dairy and eggs. These reasons range from the nutritional (“we need animal protein to live”) to the Biblical (“God gave humanity dominion over all the Earth’s creatures”) to the ethical. Yep, that’s right: some omnivores have the cajones to claim that vegans are responsible for killing more animals than flesh eaters!

Oregon State University professor of animal science Steven Davis, for one, contends that people who eat beef from cattle fed on grazing pasture spare more animals’ lives than vegans because of all the death supposedly caused by harvesting crops. While Davis’ research has appeared in such prestigious periodicals as TIME magazine and the Journal of Agricultural and Environmental Ethics, apparently no one bothered to peer-review or fact-check his methodology before publication. That is, a new analysis of the professor’s claim reveals that (surprise, surprise!) his numbers don’t quite add up.

Artist and graphic designer Mark Middleton recently calculated the true impact of food production on two categories of animals: domestic species specifically slaughtered for human consumption, and wild species killed as a consequence of agricultural harvesting. What’s more, he translated his findings into an easy-to-read graph* that enables comparison of how different diets (i.e., plant vs. flesh foods) impact animals’ lives — both by the numbers and as an interactive (filterable) visual representation of these otherwise abstract values:



Extrapolating from this diagram, we find that:

• Eating chicken flesh takes about 100 times the number of animals’ lives as eating the equivalent caloric content of vegetables.

• Subsisting on only grains for an entire year would likely cost fewer than two animals (e.g., field mice) their lives.

• Contrary to Davis’ central assertion, the number of wild animals who die as a result of beef production is much greater than occurs in the harvesting of all plant food varieties combined.

Middleton arrived at his revised conclusion by incorporating into his formula some criticisms of Davis’ work by researchers Gaverick Matheny and Andy Larney which, upon even cursory consideration, seem so basic that it’s amazing they even had to bring them up. I mean, it doesn’t take a mathematician to know that we can feed more people per acre by using land to raise crops rather than cattle, as Matheny opined, or to understand Larner’s contention that counting animals killed by predators (in addition to, say, chemical pesticides and mechanical threshers) skews the end results. So Middleton’s new presentation begs an obvious question: why did Davis’ claims go so completely unchallenged by the mainstream media and the scientific establishment when he made them?

Opinion makers’ unquestioning acceptance and promotion of Professor Davis’ flawed theory says more about meat eaters’ desperate psychological need to justify their violent destructiveness than anything else: apparently, people want to continue eating animal flesh so badly that they will even unconsciously create and cite conspicuously inaccurate data to make the case that omnivores are ethically superior to vegans. Once again, we vegans have the truth on our side, but there remain some lingering doubts about its persuasive value, because people basically believe what they want to believe. If history is any guide, many omnivores will continue to invent and propagate ways of salving their guilt by convincing themselves that meat is not murder but mercy — no matter how much incontrovertible evidence we vegans present to the contrary.

Related AnimalRightings:

- My 8-page VegNews magazine feature article “The Road to Vegetopia: (Re)Imagining the Future of Food” (illustrated by Mark Middleton)

- My blog post about Middleton’s “Virtual Battery Cage”

* For interested techies, Middleton built this interactive graphic in Adobe Flash using a data visualization library called Flare. Click here for a full explanation of the analysis and mathematical proofs.

San Francisco Protects Wild Parrots' Habitat

Board of Supervisors passes ordinance to preserve and replace vital cypress trees

Back in December 2005, IDA joined the effort to help save a grove of Monterey cypress trees in San Francisco's North Beach neighborhood because they are a favorite perch of the world-famous wild parrots of Telegraph Hill. Readers of IDA's eNews will recall that IDA started a second petition recently to support legislation proposed by Supervisor Bevan Dufty to preserve this habitat and ensure that the parrots will have a home on the Greenwich Steps for years to come.

Well over one year later, after a long campaign by many dedicated private citizens, city officials and the Northeast San Francisco Conservancy, we are proud to announce that yesterday the San Francisco Board of Supervisors voted to pass the ordinance protecting the trees! Mark Bittner, the parrots' longtime caretaker who lives next to the cypresses, noted that "the parrots were sitting in those trees squawking at the very moment the legislation passed." Thank you to everyone who signed IDA's petition and asked their family and friends to do the same. More than 1,900 caring people from every corner of the globe showed their support for the parrots by signing on.

IDA presented the results of this petition and the one we started in December 2005 at the Land Use Committee hearing in City Hall on Monday, March 5th. Committee members were impressed that IDA had gathered more than 4,500 signatures in support of protecting the parrots' habitat. The hearing chamber was packed with parrot advocates, many of whom made public statements about how the parrots benefit the people of San Francisco and add to the city's uniqueness. These included Judy Irving (the producer/director of "The Wild Parrots of Telegraph Hill") and Mark Bittner (the movie's co-star), Richard Schulke and Christine Garcia (chair and vice-chair of the Commission of Animal Control and Welfare), and IDA spokesperson Mat Thomas (i.e., me), who was also quoted in an ABC7 News story about the parrots. "A key element in this success," said Judy Irving, "was the very visible outpouring of support from all over the globe. We couldn't have done it without IDA."

With Arbor Day coming up on Saturday, March 10th, it's especially fitting that San Francisco has passed this unique ordinance to mandate the pruning and maintenance of the two older cypress trees, plant up to six new parrot-friendly trees, and protect the property owner from legal liability should the dying trees happen to fall before being replaced. Wild parrot flocks now live in such diverse urban environments as Orange County, Calif.; Brooklyn, N.Y.; Fort Lauderdale, Fla. and Chicago, Ill.; as well as numerous cities in Great Britain and elsewhere. San Francisco's innovative solution will show other cities faced with similar issues that living harmoniously with urban wildlife benefits everyone -- human and animal alike.





Watch the broadcast television premiere of "The Wild Parrots of Telegraph Hill" on Tuesday, May 29th at 9:00 pm when it airs on PBS' Independent Lens series. For more information, check local listings for your area.

Or purchase a copy of the film on DVD or VHS, as well as Mark Bittner's best-selling book "The Wild Parrots of Telegraph Hill: A Love Story...With Wings."