According to legend, from the Norwegian deep-sea fishing sardine is difficult to live ashore, if the fish is still alive when arriving, the price will be much higher, so the fishermen trying to keep the fish alive in Hong kong. But all efforts fail. Later, an old fisherman discovered a secret of success: catfish effect. The original is the sardines catfish predators, appropriate to put some catfish in sardines, can artificially create a tense atmosphere, saw it, sardines catfish convulsed with fear to flee, and greatly enhance the vitality, greatly improved the survival rate. As a result, a sardine was shipped back to the fishing port alive and kicking. Later, people called this the "catfish effect".
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