Here is the number of amphibian on the planet:
There are 3,800 species of frogs. The tadpole begins to explore its environment at 15 days; it takes a month to become a frog. In winter, it breathes only through the skin, because it lives in the mud. It eats worms, centipedes, spiders. It takes 21 days to lay eggs after fertilization. The eggs take 3-4 months to hatch. A frog lives between 6 and 7 years.
In captivity, a toad can live up to 40 years.
There is a total of 2.3 billion of amphibians on Earth.