- a breeding mechanism developed by some insects, most notably tsetse flies. The single egg of the tsetse develops into a larva inside the uterus where it is fed by a milky substance secreted by a milk gland inside the uterus. The cockroach species Diploptera punctata is also known to feed their offspring by milky secretions. Toxeus magnus, an ant-mimicking jumping spider species of Southeast Asia, also lactates. It nurses its offspring for about 38 days, although they are able to forage on their own after 21 days. Blocking nursing immediately after birth resulted in complete mortality of the offspring, whereas blocking it 20 days after birth resulted in increased foraging and reduced survival. This form of lactation may have evolved from production of trophic eggs. See also Lactation room Galactogogue Milk line Male lactation Udder Breastfeeding Lactation failure Lactation suppression Erotic lactation Hypothalamic–pituitary–prolactin axis Roman charity Pregnancy References External links How mammals lost their egg yolks—Did mammals develop nutritional milk before or after they abandoned yolky eggs? (New Scientist, 18 March 2008) Animal physiology Breastfeeding Exocrine system Glands Reproduction in mammals Milk Secondary sexual characteristics Breast milk Human female endocrine system