It's for singing. There is a bulging thing on the frog's mouth that can make a sound. It likes to sing loudly on rainy days in summer. In hot summer, frogs usually hide in the grass and occasionally make short calls.

If there is a cry, the people next to them will scream a few times, as if singing to each other. Frogs are happiest after the heavy rain. At this time, there will be dozens or even hundreds of frogs croaking endlessly, and the sound can be heard for miles away. ?

Extended data

Frog Habits: Vocal cords are the vocal organs of frogs. Located above hilar cartilage. On both sides of some male frogs' squabbles, there are external sound sacs that can expand and vibrate, and the sound sacs produce * * * sounds, which make the frogs' songs magnificent and loud. After the rain, when you stroll to the pond, you will hear the cries of male frogs echoing each other, one after another, gathering into a chorus.

Frog shape: the body length can reach 10 cm, and the skin is rough and covered with warts. The back is yellow-green, brown and irregularly striped. The ventral surface is white, and there are transverse spots on the front and rear limbs. Toes are pointed and round, all over webbed toes. The forelimbs are thick, the finger pads are developed and gray.

The male frog has a pair of external sound sacs. Living near Shan Ye, paddy fields and ponds. Predating insects, earthworms, spiders and other small frogs. Produced in East China, Central China, South China and Southwest China. It belongs to the national second-class protected animals.

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