It's what's known as a bioluminescent burglar alarm, and just like the alarm on your car or your house, it's meant to cast unwanted attention onto the intruder, thereby either leading to his capture or scaring him away.
这可以理解为一种生物荧光的防盗警报器。 就想你车上或家里的那种警报器一样， 它是为了把一些多余注意力投射给入侵者， 从而或者误导它的注意力 或者吓走它。