A Very Rare Creature Comes to Life in a Museum: A Half-Male, Half-Female Butterfly

During a museum exhibit at Drexel University called Butterflies!, Chris Johnson was working as a volunteer for the university's Academy of Natural Sciences. One autumn day during October, a butterfly that was just coming out of its cocoon (more specifically its "chrysalis"), caught his attention.

When the tiny creature opened its wings slowly, Johnson saw something so rare that he couldn't believe it. The butterfly had two brown wings with white and yellow spots on its right side and two darker wings with blue and purple marks on its lefts side. Johnson said, "The wings were so dramatically different, it was immediately apparent what it was." He knew that he had just stumbled upon a a half-female, half-male butterfly. "I thought somebody was fooling with me. It is just too perfect," he added, according to Discovery.

The condition that made the butterfly half-male and half-female is called bilateral gynandromorphy. Experts classified the specimen as a member of the Lexias pardalis species,

Jason Weintraub, an Entomology Collection Manager and a lepidopterist, said, "Gynandromorphism is most frequently noticed in bird and butterfly species where the two sexes have very different coloration."

Weintraub when asked about how this phenomenon occurred explained to Discovery, "It can result from non-disjunction of sex chromosomes, an error that sometimes occurs during the division of chromosomes at a very early stage of development."

Even though it is known to scientists that this phenomenon is quite rare, it is not easy to tell how rare it is mainly due to the fact that gynandromorphism can easily be overlooked in species with similar-looking males and females.

For people who are interested in seeing this rare creature, the half-and-half butterflies will be displayed at Drexel University's Academy of Natural Sciences in Philadelphia from January 17 through February 16.