These guys are jumping spiders, but they waggle their legs like antenna, and I guess the ants buy it. But then, people have gotten turkeys to try to mate with socks on sticks... and then again, there's porn. But yeah, spiders acting like ants, infiltrating their society, and then eating them. It's like a nature's social predator. Awesome!
As it turns out, ant mimicry isn't exactly a "new thing," other bugs have been doing it for quite some time. Take Macroxiphus, a katydid that mimics ants in its larval stage:
And what do you know, but flies do it, too:
But it's not just ants that get mimicked. Check out Macroglossum stellatarum, a moth that mimics a hummingbird:
And that's not all that moths mimic, either; there's a hornet moth, and a wasp moth, too!
And let's not forget the stick bug (which, I just learned today, actually makes a good pet!) and the leaf bug, the first two mimics I had ever learned about. But the top of the mimic heap, without a doubt, is the mimic octopus. This guy can mimic the shape, coloration, and behavior of over a dozen different animals! Check it out:Further reading:
World's Weirdest Moths (or: Why Moths are Way Cooler than Butterflies)
Wikipedia's mimicry page
All uncredited photos taken from Wikipedia.