To stop global warming, eat some grubs. Researchers compared big livestock with bugs to determine environmental impact:

To quantify the animals’ greenhouse gas footprints, the team measured the five insects’ growth rates and their production of the greenhouse gases and ammonia — also a pollutant but not a greenhouse gas. They compared these to data already available on the cattle and pigs’ growth rate and the rates at which they emitted the same pollutants.

Cattle produced the least carbon dioxide per unit of body mass. However, the picture changed once growth rate was considered. The data indicated that insects grow more rapidly, and they emit less carbon dioxide per unit of weight gained than do cattle and pigs. The cockroach was the clear winner in this latter category; meanwhile, cattle produced the most carbon dioxide per pound (or kilogram) gained. [The Truth about Cockroaches]

Interesting question to all you vegans and vegetarians out there: if we replaced livestock with bugs (insects, arachnids, other arthropods, etc.) as our primary source of protein, would you eat it? I get that uber-vegans won’t, but for those of you who just don’t like the idea of eating higher order critters.