A Tiny Killing Machine | Explorer
So how can this animal with such a minute brain have stereo vision, and how would you even test this? Vivic decided that the best way was to take the insect to a 3D action movie. Really, in order to see the movie, Vivic needs to make some very, very tiny 3D glasses for the pr mantis.
We came up with the idea of 3D glasses with these two different glasses on each eye. Each eye could be shown a different stimulus. So after various attempts at getting this done, the one approach that seemed to work was to use colored filters. It's a quick procedure using beeswax to attach the 3D glasses, and also a device that holds the Mantis in the stand for the experiment.
So I think we've got the green filter on the left eye and the blue filter on the right eye. So I'm just going to put it on the stand. How can they make sure the Mantis is really seeing 3D? Pray mantises will only strike at prey if they are close enough to their target. Jenny and Vivic make sure that the computer screen is out of the mantis's strike range, but the 3D target is within it.
If the Mantis actually sees stereoscopically, it will strike at the 3D target thinking it is close enough to go in for the kill. Okay, should we go? Yep, and let's [Music] go! Wait for it, wait for it... and strike!
The obvious reason why pr mantises would have evolved 3D vision is for predation. If a prey comes within range, they'll reach out and grab it very quickly with a strike. The strike's very all or nothing; you have to get it right. There isn't going to be a second chance, so it's very important for the Mantis to know exactly how far away the prey item is before it releases its strike.
Yes, we got a strike! Yeah, fantastic! Yeah, it definitely works, and uh, yeah, brilliant! Jenny and Vivic have a lot more experimentation to do to figure out the algorithm that defines a pr mantis's stereo vision.
It could be that it's a different type of stereo vision than ours. One possibility that I see is that mantises have kind of evolved a quick and dirty stereo vision. Maybe it's not as good as ours; it doesn't work in as wide a variety of images. It does the job for them, and I think that will be really interesting, not just from an evolutionary point of view, but perhaps it's something we could use. [Music]