Walking stick insect

Stick insects can reproduce parthenogenetically, without the need for males.
Stick insects are a nation of Amazons, able to reproduce almost entirely without males. Unmated females produce eggs that become more females. When a male does manage to mate with a female, there's a 50/50 chance their offspring will be male. A captive female stick insect can produce hundreds of all-female offspring without ever mating. There are species of stick insects for which scientists have never found any males.