The life cycle of a frog is easy to understand if you can follow the basic morphological development of amphibians. Frogs and toads alike will mate in a position known as amplexus. In this position, the male can fertilize the eggs that the female lays. The eggs will hatch between six and twenty-one days after fertilization.
The eggs of a frog are considered to be a delicious delicacy for many predators that would use the frog’s eggs as their main source of food. Although many of the eggs will not hatch, some will begin to grow and elongate in the egg. At the right time, the young tadpole will be ready to be born.
The newly born tadpole is still too immature to eat algae. It will remain in very shallow water by plant life such as grass or weeds. The juvenile tadpole can survive on the yolk that is still present in its intestines for about a week’s time. The tadpole will then be able to eat algae and swim more easily.
After about a month, the tiny tadpole will begin to grow teeth and have more mature gills. Their intestines will begin to mature more, as will the ability to process more food. Their gills will begin to have skin grow over them. Over time, the gills will disappear altogether. Tadpoles are known to be social at this stage; they will gather in groups and even appear to school like fish.
Two months after the hatching of the tadpole, it begins to look more like a frog. It has begun to grow legs that will elongate over the next two weeks. The arms begin to protrude from their sides and then elbows. The tadpole now resembles a frog more closely. The only remnant of its past is the long tail, which remains for a while longer. The diet of the tadpole has improved; it can now eat larger insects and will continue to grow. It still prefers a totally aquatic habitat and will not migrate onto land for a couple of weeks.
Twelve weeks after its birth, the tadpole has only the tiny remnant of its tail. It now looks like a mature frog. It has nearly reached mature size, and will soon leave its aquatic home and test its new legs on land. As a mature frog, it will still enjoy the water, but it can now spend the majority of its time on land. The frog is ready to strike out and mate. It will soon mate and begin the cycle again.
