快猫短视频

FISH play follow-the-leader to find food. If one fish knows what it鈥檚 doing,
the rest of the shoal will follow it, says a Canadian biologist.

St茅phan Reebs of Moncton University in New Brunswick trained shoals of
golden shiners to expect food at a certain place and time each day in their
tanks. Then he replaced some or all of the 12 fish in each shoal with untrained
counterparts.

Shoals containing a few experienced individuals spent much more time in the
feeding area than shoals with no trained fish. The effect was stronger when
there were more fish that knew about the food, but Reebs was surprised to find
that a single fish could persuade its shoal mates to follow and leave the shady
area of the tank where they would normally stay all day. 鈥淚 expected that the 11
fish would have too much inertia to be entrained by just one leader,鈥� he
says.

Reebs isn鈥檛 sure how the informed fish tell others to follow. He thinks that
perhaps they make particular movements to signal their intention or release
chemical cues in the anticipation of food.

鈥淩eebs has made the first step in showing that fish can communicate knowledge
about foraging opportunities and thereby influence the behaviour of the whole
group,鈥� says biologist Brian Wisenden of Moorhead State University in Minnesota.