How many wild animals are there?

Abstract

This article attempts to estimate the number of wild animals on Earth. It provides estimates for various taxa, including wild mammals, birds, reptiles, amphibians, fish, earthworms, dust mites, coral polyps, terrestrial arthropods, rotifers, gastrotrichs, copepods, nematodes, protozoa, and bacteria. The paper discusses the methods used to derive these estimates and acknowledges their uncertainty. Overall, the author argues that wild invertebrates likely dominate the moral calculus of suffering on Earth, followed by fish and, perhaps, by wild mammals and birds. – AI-generated abstract.