Conjoined Twin Butterflies!
So, my 6-year old son calls me out to the passion flower vine, telling me that there are two butterflies lying on the ground, one on top of another. I explain that they are likely mating, and tried to go back to my work, but he INSISTED that I come out to see them. Imagine my surprise to find that they are, in fact, *conjoined twin* gulf fritillary butterflies, sharing a single abdomen! I think the picture 042 shows the join the best, albeit a bit out of focus. The other pictures are much clearer, but not as good of a view of the join. Amazing! Didn’t find anything about this anomaly online, so I thought I’d see if you were interested in having a look-see…. My question – Would they have come from conjoined caterpillars, or would they possibly have been a single caterpillar prior to the cocoon? Thanks for any insight!
San Marcos, CA
Your letter gave us a good chuckle. These actually are mating Gulf Fritillaries. Taking a good look at our numerous Bug Love pages will reveal that many insects interlock during mating to ensure the fertilization process. Interestingly, the disection of butterfly genitalia is the only sure way to distinguis species sometimes. We are not certain if the cellular structure of an insect egg would even permit conjoined twins, but if it did, the immature insect would surely not survive since the mutation would not be an advantageous one. Since most insects don’t care for their young, exceptions being the social ants, bees, wasps, and termites, and some oddities like Bess Beeetles, a mutated larva that couldn’t survive on its own would die.