To the evolutionarily oriented clinical psychiatrist, the discipline of behavioural ecology is a fertile basic science. Human psychology discusses variation in terms of means, standard deviations, heritabilities, and so on, but behavioural ecology deals with mutually incompatible alternative behavioural strategies, the heritable variation being maintained by negative frequency-dependent selection. I suggest that behavioural ecology should be included in the interdisciplinary dialogue recommended by Keller & Miller (K&M).