The researchers found that when two swarms of crabs collide, they merge and continue in a direction that is the sum of their velocities

I see this being incorporated into a maths lesson about vector addition.

That gives me some 3 Body Problem vibes.

Here’s the summary for the wikipedia article you mentioned in your comment:

Mictyris guinotae is a species of soldier crab of genus Mictyris, endemic to the Ryukyu Islands of Japan. They were named after Danièle Guinot, a professor at the Muséum national d’histoire naturelle in France, and were first treated as a separate species in a tribute volume to Guinot.

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