by Matthew Cobb
Over at Myrmecos, Alex Wild has published this picture by William Piel and Antonia Monteiro of this amazing moth, Macrocilix maia, which lives in Malaysia and Borneo. This is a kind of Rorschach test. What do you see?
On his Flickr stream, Allan Lee published another photo and writes: “The pattern looks like 2 flies approaching some bird dung. As my friend have highlighted, we notice that there’s a bad smell emitted by this moth. This is really an interesting moth trying to fool it’s predators by both sight and smell.”
You can find other Flickr pictures of M. maia here.
On Twitter, Alex (@Myrmecos) and Ed Yong (@edyong209) had a discussion about whether this pattern is indeed ‘meant’ to show a pair of flies. Ed wondered whether Alex was reading too much into it, to which Alex replied “The full flickr collection of this species won me over”.
It certainly looks to me like a fly – what species?! 😉 – and presumably there are a pair of flies here because the genetics of butterfly wings makes it very difficult not to be symmetrical.
However, there is a much bigger issue here. What is the adaptive value of looking like something else that could be eaten, like a fly? Or even worse, a pair of flies? OK, if the “flies” were attacked, then the moth might only get its wings damaged, rather than its body. But that would still be a substantial cost. And surely the added smell would attract either real flies, or predators on flies… It’s an odd story. As Alex says, this is a PhD project just crying out for funding, a bold supervisor and an intrepid student.
[EDIT: Try walking away from your computer screen (not yet, you ninny) and looking at the image from a few metres away. Now it most definitely looks like flies (especially the left hand one). But why?]
[EDIT 2: Antonia Monteiro mailed me, giving me permission to reproduce the photo and saying: “Yes, this moth is quite extraordinary. Bill and I also wrote a small note in a Yale internal magazine about it. It contains precise coordinates as well as the names of the people that helped us identify this moth.”]