Forty-five years of progress after a key paper about the evolution of cooperation

Ever since Charles Darwin, scientists studying evolution have grappled with how cooperative behaviours that are costly to an individual but beneficial to others can be consistent with maximal fitness. In 1981, writing in Science, Robert Axelrod and William D. Hamilton1 presented key findings on how such cooperation can evolve. They accomplished this by weaving together two emerging ideas of the time in this area of research.

Nature 651, 894-895 (2026)

doi: https://doi.org/10.1038/d41586-026-00802-7

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Competing Interests The authors declare no competing interests.

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