Instructions
Determining Sex
Notice the moth's activity level. Males are much more active than females, and may even fly a little bit. Females predominately stay close to their hatching area.
Look at the antennae. Male antennae are much "fuzzier" than females. The olfactory hairs on the male's antennae allow him to follow the pheromones the female produces to find a mate.
Compare the sizes. Female adults are much bigger than their male counterparts. Females may also extrude a visible, scent-producing gland from the rear, while males have a flap. In the larval stage (caterpillars), larger caterpillars become females and smaller ones develop into males. Caterpillars in between the largest and smallest specimens may turn into either, according to SueKayton.com.
How to Distinguish Female Silkworms From Male Silkworms
Silkworms are one of the few species not found in the wild. They have mostly lost their ability to fly, although they still form wings. They also eat only one food as larvae (adults do not eat): Mulberry leaves. While it is unclear how to positively determine the sex of the larvae (silkworms), adults can more easily be sexed due to distinct differences.