The "sea slug" is a nudibranch that glows ... When it felt threatened, it lit up with a bioluminescent glow. The scientists say the glow seems to be a defence mechanism, along with something ...

Sea slugs!” We are almost at the car when he approaches ... under which the nudibranchs glow in even weirder ways. Toward the end of the dive, I turn a rock over and find a large slug-like ...