Marine animals repeatedly evolve collective behaviours because their shared environment rewards coordinated responses to food scarcity, predation and physical conditions.
Researchers Kelly Benoit-Bird and William Oestreich reviewed collective behaviour throughout the ocean’s pelagic zone, examining organisms ranging from plankton to whales. Their analysis connects schooling, swarming, cooperative foraging and vertical migration with three recurring environmental pressures: patchily distributed food, exposure to predators and the movement of seawater. The review also considers how collective behaviour itself influences other organisms, producing feedback between groups and potentially creating multispecies collective structures.
