The weight of responsibility: Biomass of livestock dwarfs that of wild mammals

I saw metrics like this a while ago but it’s still hard to wrap my head around. We rarely see this enormous portion of the animals that outnumber us so much.

I grew up on a farm in the rural western US, and our few cattle lived in nice little fields like you’d imagine, but I’d occasionally go by intensive farms and you can see how they pack so many animals into such a small space that they spend their whole lives in. It’s so near but so far from all of us. And the reactions from people I know varies widely to this information or these sights.

The new report shows that the biomass of wild mammals on land and at sea is dwarfed by the combined weight of cattle, pigs, sheep and other domesticated mammals. A team headed by Prof. Ron Milo found that the biomass of livestock has reached about 630 million tons—30 times the weight of all wild terrestrial mammals (approximately 20 million tons) and 15 times that of wild marine mammals (40 million tons).