In one of our classes there was some talk about how a mantis' eyes looks like they're looking at you from whichever direction you look at the mantis. At this point I wondered why the mantis I caught had black eyes instead of pupils.
Googling wasn't that much of a help but I did find some sites that had possible answers. So the eyes can change color. But why?
Photo forum with a hypothesis that darkness effects mantis eyes. I don't recall how it looked when I caught it but it was in my backpack for an hour or two.
According to a reply here, it's caused by a lack of humidity. Probably doesn't apply to the one I had.
The eyes of my mantis are still black to this day.
In the freezer.