Loss of altruism (and a body plan) without a loss of genes

The evolutionary loss of the ‘altruistic’ worker caste in ants is not accompanied by a loss of genes, an international team of researchers has found. The results reported in this new research add to a growing body of literature suggesting that many traits may evolve by tweaks in the regulation of pre-existing genes and networks. Phenotype gain and loss may be facilitated by changes in the environment within and outside of the organism, not necessarily requiring changes to protein coding genes, just changes to when and how they are used.