Various aspects of floral morphology promote allogamy. In humans, the fertilization event is an instance of allogamy. This mechanism favours cross pollination (allogamy or xenogamy) in these plants. Thus post-pollination selection may occur in order to promote allogamy and avoid inbreeding depression. The dominant reproductive system is an allogamy (cross-pollinating) system. Monocots have mechanisms to promote or suppress cross-fertilization (allogamy) and self-fertilization (autogamy or geitonogamy). These two examples are not however typical of the genus, which commonly reproduces through allogamy.