Montana Public Radio

Bug Bytes: Parthenogenesis – Walking Sticks

Feb 5, 2019

When it comes to finding a potential mate for female Australian walking sticks, they can afford to “swipe left” all day.

That’s because many species of walking sticks (or phasmids) are parthenogenic, meaning they can successfully produce offspring without needing to mate. This is a form of asexual reproduction where the growth and development of an embryo occurs without fertilization.

More accurately, female Australian walking sticks are facultative parthenogens -- meaning they have the ability to mate; it just depends on the availability of a male.

But it turns out that it may not just be the physical lack of a male mate. A study published in the journal Animal Behaviour in March 2015 found that female Australian walking sticks will mate with males when it suits them, having found ways to repel them so they can reproduce without any male interference.

If she chooses to swipe left and handle reproduction on her own, all of her eggs will produce female offspring; essentially genetic carbon copies of herself, or mini-mes. Only when a male is part of the reproductive equation will any of the eggs produce male offspring.

This unique reproductive route is not limited to just certain species of walking sticks. It occurs in other species of invertebrates like aphids, bees, ants, and some species of scorpions. While rare, it also occurs in some species of fish, snakes, birds, and lizards. In fact, whiptail lizards have evolved to a point where no males exist.

So for all the male Australian walking sticks out there hoping to pass their genes on to the next generation, get your act together. Because with or without you, life will go on.

BugBytes is made possible by the Missoula Butterfly House and Insectarium, and Montana Public Radio. This show is also supported by funding from the Greater Montana Foundation: Encouraging communication on issues, trends and values of importance to Montanans.