You're stressing us out, man!

Remember when we learned that crustaceans actually feel pain here? In short, scientists offered crabs two shelters: one normal and one that delivered a shock. After being exposed to the electric shelter, the crabs had a learned response to avoid that sensation (presumably pain) and only choose the normal shelter.

it's electric!

Well, stemming from that research, scientists are now learning that crustaceans may feel anxiety too! I mean, it's not too shocking (I know...) that electrocuting  an animal would stress it out, in our human understanding of the phrase, but scientists are observing behaviors that can be attributed to a stressed response. To test for anxiety in crustaceans, scientists exposed some crayfish to an electric field then put them in the test environment. The environment itself had no secret shocks, but rather had different light treatments: light places and dark places. All animals that weren't shocked before placement wandered around in both the light and dark environments, as if they hadn't a care in the world! All animals who were electrocuted prior to placement chose to stay in the dark places - in the wild this would be like them finding cover and hiding. They had experienced something that stressed them, so they were staying away from a threatening, exposed place!

"man, you cray!" - 'stressed' crayfish

This, along with some physiological work the researchers did as well, means that instead of calling them "stressed", I can take away the air quotes that indicate I'm just anthropomorphizing their behavior and call them stressed!

Not anymore, Dr. Evil. Not anymore.