By Susan Milius
The giant thing swam closer to the sergeant damselfish’s nest on the coral reef, but the paterfamilias guarding the eggs didn’t back down one bit. He darted and nipped threateningly at the huge, intruding shape, that is, to the extent that a 13-centimeter fish can threaten something that’s more than 10 times its length.
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“He bit my finger,” remembers the looming menace, aka Andrea Manica of the University of Cambridge in England. “It was not even a particularly painful pinch. He didn’t have any chance of hurting me in any way except for becoming rather a nuisance. It’s quite difficult when trying to take accurate measurements when the [tape measure] gets continually grabbed and pulled.”