The word ‘amphibian’ means ‘double life’. It describes an animal that spends part of its time on land, and part of it in water. It can breathe through its skin.
Frogs are one of the most well-known amphibians. They start life as eggs and become tadpoles with gills living exclusively in water. Then they undergo metamorphosis, develop lungs and can survive both on land and in water.
On rainy nights, you will hear frogs making loud mating calls. Once mated, the female lays many eggs into the water. For instance, a female bullfrog can lay more than 20,000 eggs at times. Most, however, become food for other predatory animals.
Frogs are amazing bio-indicators because they are very sensitive to their surroundings. Their populations can fluctuate drastically, and their abundance often indicates a healthy environment.