Discovering one reason why swarming evolved offers tantalizing clues on how intelligence developed
by PhysOrg staff
Many animals – from locusts to fish – live in groups and swarm, but scientists aren’t sure why or how this behavior evolved. Now a multidisciplinary team of Michigan State University scientists has used a model system to show for the first time that predator confusion can make prey evolve swarming behavior.
Swarming allows groups of animals to accomplish tasks that they can’t do alone, such as defending themselves from a much larger predator.
"There are both costs and benefits to swarming and all other behaviors," said Christoph Adami, MSU professor of microbiology and molecular genetics. "The benefits are discussed all the time. But the litmus test is whether a behavior evolves because of those benefits. If it doesn’t evolve, it doesn’t mean it’s not beneficial, but if it does evolve, it’s proof that the behavior has benefits that outweigh its costs. Our model system shows that predator confusion was enough of a selection pressure to evolve swarming behavior in prey."…