A few weeks ago my family went to the National Zoo in DC, to see the baby panda at least once before it was all grown up, and to say hi to the octopus and check on the naked mole rats and such. (The bat house, which has long been my favorite, was sadly closed for some reason.)
It's pretty typical that the only good animal picture I got was of something on the same side of the fences as us.
Google tells me that this bright little guy is a differential grasshopper, Melanopus differentialis. (It also tells me that he's a he, based on the shape of his back end - isn't Google great?) He's also apparently at an extreme edge of his range -
this map shows the species following the fall line right up the middle of DC, and cutting off my part of Maryland entirely; and they're most common between the Mississippi and the Rockies. Which explains why I've never seen those pretty black-and-yellow chevrons before!
(I'm afraid I have no idea what he's sitting on - I'm not good with grassy types.)