Mating

Ecology

Biology

Inclusive fitness

Hymenoptera

Kin recognition

Selection (genetic algorithm)

Computer science

Evolutionary biology

Eusociality

Mating system

Artificial intelligence

Kin selection

Zoology

Science

Close relatedness has long been considered crucial to the evolution of eusociality. However, it has recently been suggested that close relatedness may be a consequence, rather than a cause, of eusociality. We tested this idea with a comparative analysis of female mating frequencies in 267 species of eusocial bees, wasps, and ants. We found that mating with a single male, which maximizes relatedness, is ancestral for all eight independent eusocial lineages that we investigated. Mating with multiple males is always derived. Furthermore, we found that high polyandry (&gt;2 effective mates) occurs only in lineages whose workers have lost reproductive totipotency. These results provide the first evidence that monogamy was critical in the evolution of eusociality, strongly supporting the prediction of inclusive fitness theory.

Ancestral Monogamy Shows Kin Selection Is Key to the Evolution of Eusociality