Animals

Crows recently demonstrated an understanding of the concept of zero. It’s only the latest evidence of animals’ talents for numerical abstraction — which may still differ from our own grasp of numbers.

Showy male competitions over mating privileges have grabbed scientists’ attention more often, but new work hints that sexual selection is also widespread among females.

Animals sculpt the optical properties of their tissues at the nanoscale to give themselves “structural colors.” New work is piecing together how they do it.

The discovery of a gene shared by two unrelated species of fish is the latest evidence that horizontal gene transfers occur surprisingly often in vertebrates.

Embryonic cells can self-assemble into new living forms that don’t resemble the bodies they usually generate, challenging old ideas of what defines an organism.

A glass sponge found deep in the Pacific shows a remarkable ability to withstand compression and bending, on top of the sponge’s other unusual properties.

Carpenter ants need endosymbiotic bacteria to guide the early development of their embryos. New work has reconstructed how this deep partnership evolved.

Recent major surveys show that reductions in genomic complexity — including the loss of key genes — have successfully shaped the evolution of life throughout history.

Emperor penguins display rigorously geometric spacing and mathematical efficiency when they huddle together for warmth, which may reveal secrets to their overall health.