Why do frogs croak?

1. 1

   Lue says

   After rain, ponds can fill with frog songs. Almost always, it's the boy frogs doing the singing. Each kind of frog has its own song, and the girl frogs listen for the song of their own kind. So a croak is a boy frog calling out, here I am!

   For ages 4–7
   Hear Lue

   Checked against Why do frogs call? (Australian Museum)

2. 2

   Why is a frog's croak so loud?

   Under a calling frog's chin is a baggy pouch of skin called a vocal sac. When the frog calls, the pouch fills with air and puffs up like a balloon. The puffed-up pouch makes the call much louder, so it carries right across the pond.

   For ages 6–9
   Hear Lue

   Checked against How can you tell a male from a female frog? (Australian Museum)

In Lil' Phil, reaching the bottom of this wonder earns a sticker for Lue's collection.

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