The 10% rule

Abstract

It has been estimated that the human species constitutes about 5% of the total animal biomass of the world (ants do better, at 20%), a value which is matched by only one other mammal ? our own domesticated cattle (McNeill 2000). There has been some worry about the methane produced by so many cows, because of their contribution to greenhouse gases ? a concern that led to the so-called fart tax proposed in New Zealand in relation to Kyoto commitments. While it might be difficult to agree on the biggest problem facing the planet, it is unlikely that farting cows would make the short-list, and it is not surprising that the fart tax foundered on political realities.