I have a new piece in the New Yorker’s Elements blog about our tendency to underestimate animals that are very different from us, such as sponges and ctenophores. Check it out.

Last month, in the journal Trends in Ecology & Evolution, a group of scientists published a tub-thumping defense of sponges and other supposedly simple animals. In their paper, Casey Dunn, Sally Leys, and Steve Haddock argue that humans have systematically underestimated these creatures, largely because of our innate bias against organisms outside our taxonomic clique. That clique, actually called a clade, includes all of the so-called bilaterians—animals with left-right symmetry that share a single ancestor. Tigers, hummingbirds, octopuses, scorpions, crocodiles, mantises, sharks, earthworms: all are bilaterians.

Dunn, Leys, and