Lobtail Feeding//
　　A long way away,/in the North Atlantic Ocean,/whales also exhibit a kind of culture.// Ed Yong,/a science journalist,/writes about social learning among whales://
　　In 1980,/a humpback whale in the Gulf of Maine/started doing something different.// All its neighbors would catch small fish/by swimming in circles below them,/blowing curtains of bubbles,/and then plunging straight up.// Then one individual,/out of the blue,/started smacking the water surface with its tail/before diving down/and blowing bubbles.//
　　This behavior is called “lobtail feeding,”/and no one knows why it works.// Whatever the benefit,/it went viral.// Just eight years/after the first innovative whale started doing it,/20 percent of the Maine humpbacks/had picked up the technique.// Now,/it’s more like 40 percent.// What began as one whale slapping the water/is now a tradition.// The obvious explanation/is that the whales were learning from each other.//
　　Skeptics will argue/that there could be other explanations.// The lobtail technique may have a genetic basis/and be passed down without social learning.// Maybe environmental changes are responsible.//
　　But a group of researchers used the whale data/to simulate the spread of lobtail feeding.// The results were so clear/that the leader of the research team concluded/that social learning was important in the spread of the behavior.//