by Katie Bowell, Curator of Cultural Interpretation
Recently, our male African millipede, Leopold, shed his exoskeleton. Charlotte, our female African millipede, must have thought Leopold was looking snazzy in his new exoskeleton because, not long after, they mated.
Please excuse the blurriness of the photo – it’s hard to take pictures through the terrarium wall, and we wanted to give those two a little privacy.
None of us had ever seen millipedes mating before, and to be honest, when we first saw the millipedes acting “funny,” we weren’t sure what was going on. It almost looked like the millipedes were trying to hug each other – raising the fronts of the bodies up off the dirt and pushing them against one another. Well, it turns out that’s what mating millipedes look like.
Adult millipedes attract mates by emitting pheromones to locate others of the same species. Some males rub their legs together to attract females. The way to tell male and female millipedes apart is to look for gonopods. Gonopods are modified legs on the seventh segment of the male millipedes’ bodies that are used to transfer spermatophores (packages of sperm and other nutrients) to a female. When the millipedes looking like they’re hugging (or beginning to waltz), that’s the male transferring a spermatophore to the female.
Females don’t need to use the sperm they’re given right away; they store it and use it to fertilize their eggs as they lay them. An African millipede like Charlotte can lay up to 2,000 eggs in a chamber she constructs under the dirt, and the babies, or neonates, will hatch 3 weeks later. When they first hatch, the neonates will be very small, white (because their exoskeletons haven’t hardened and darkened yet) and will only have three segments. As the neonates continue to grow, they’ll add new segments and more legs each time they molt.
Will we have any neonate millipedes joining us in the future? We’ll have to wait and see.
Mating millipede photo by Michelle Brannon, Animal Caretaker