It's easy for us humans to fish things out jars with narrow openings. We have things like utensils and opposable thumbs and if all else fails, the ability to turn the jar over. Then, presto! We have that last stubborn pickle.
It's not so easy for other animals that don't have our flatware or thumbs, but that doesn't stop some of them. A new study published in Nature has found that the Hawaiian crow (Corvus hawaiiensis) is a crafty tool-user. The crows will turn to sticks into skewers to draw out pieces of meat from logs, and they'll even go about seeking out the best stick for the job. If one stick is too short, it gets tossed aside. Too thick? The bird moves on.
Given the fact that the Hawaiian crow is extinct in the wild, it would be reasonable to think that the birds' tool use might be limited to a certain group of birds that live in their sanctuaries, but that's not the case. Not only did 93 percent of the birds observed use sticks as tools across the preserves, but researchers noted juvenile crows exhibiting tool-using behavior as well, and they did so without any social training from older crows.
As the video points out, the Hawaiian crow isn't the only the bird that turns to tool-based solutions. Another tropical crow, the New Caledonian crow (Corvus moneduloides), has impressed researchers with its excellent use of tools, but up until this study, no other crow had demonstrated such finesse. The two species grew up in similar environments, but they evolved independently of one another, meaning the crows weren't swapping tips on which stick is the best one for the job. Researchers think the birds' similar environments — including a lack of competition and predators — gave them ample time to experiment with tool use. The same way we figure out whether or not the salad fork works better than the dinner fork for spearing that last pickle.