16. Men can lactate too – Male mammals possess mammary glands and can produce milk, although this is rare. Certain disorders involving the pituitary gland, for example, cause it to produce prolactin, which stimulates milk production. The Dayak fruit bat is the only species in which male lactation is widespread. It’s unclear whether they actually breast feed or if milk production is a side-effect of a diet rich in phytoestrogens – plant molecules that mimic female hormones.
