A fishy friend group

Whether it's aware or not, this whale shark is about to become these flanking fishes' very own commuter bus. While they bear the ominous nickname 'sharksucker,' they're actually not even an annoyance to the deep-sea juggernaut. In fact, the bond between remoras and larger fish like sharks is a classic example of symbiosis, either commensalism (where one animal benefits from the relationship, and the other is neither helped nor harmed) or mutualism (where both animals benefit). In this case, the remora reaps rewards by attaching to the larger animal via a suction cup on its underside, hitching a free ride to conserve energy. Research also suggests the friendship isn't one-sided, as the suction-cup action may help remove parasites and dead skin from the shark.