Tadpoles go through different stages of growth and development to become a frog. The tadpole life cycle is called metamorphosis.
Most species of frogs will lay their eggs in water usually in spring (some species lay eggs on land). A female frog will lay the eggs and the male frog will fertilise them as they are laid.
Once the eggs are fertilised, the female frog will cover them in a jelly like material which allows them to float to the surface. This jelly like mass of eggs is called frog spawn.
Fun fact: A female frogs can lay as many as 20,000 eggs!
As the eggs start to develop you can see the little tadpoles inside the eggs. Tadpoles can take anywhere from 6 to 21 days to hatch.
The first few days of the tadpole life cycle can be very dangerous. This is because they could be eaten by bigger creatures.
After 7 to 10 days (or more depending on the species) the tadpole will begin to swim around.
Tadpoles have fin-like appendages, or a dorsal fin and a small tail. The tail helps them to swim in water. So they can breathe underwater, tadpoles have gills.
The tadpole will start to eat small water plants, such as algae.
Teeth and Leg Development
The next stage of the tadpole life cycle will be the development of teeth. This happens at around 4 weeks, meaning they can start eating different types of plants and insects. Their internal organs also develop allowing them to digest more nutrients.
Legs can develop anywhere from 5 to 9 weeks. First the back legs, then the front legs. As well, the head and abdomen will start to get bigger too.
Their gills begin to gradually disappear and the tadpoles will start to eat bigger insects.
By the end of the 12th week, with just a tiny bit of a tail, the tadpole now looks more like a frog at last!
Now is the time for the tadpole to leave the water. Their lungs start to function completely, the tail disappears and the mouth widens. Skin and other parts of the body develop completely.
It takes between 13 to 16 weeks for a tadpole to become a frog depending on the environment, food and nutrition.
Most tadpoles complete their development in their first year. Though you may see them in the water later in the year, this is called over-wintering.
Credit: You Tube