Tadpoles - Early Amphibian Life Cycle
July 27, 2022
Photographer: Michela Meda
Summary Author: Michela Meda
The photo above shows tadpoles of the common toad (Bufo bufo) found in Eurasia and in the north-west of Africa. These unique creatures are recognizable by their black color and tail that is relatively undeveloped compared to its body.
The tadpole is the larval stage of annular amphibians, such as frogs and toads. This early life stage more closely resembles a small fish than to an amphibian. During tadpole stage, the body is characterized by two distinct traits: a roundish form- including the head- that is paired with a long, flexible tail. In contrast to adult amphibians, tadpole breathes through gills and generally eats vegetables. Following the tadpole stage of life, an amphibian will have to undergo a process of metamorphosis that will lead it to the final adult form.
Some species of frogs that lay a gelatinous mass of eggs in the water will hatch within about two weeks. Following hatching, the tadpoles will gather in many nearby banks. This is a survival strategy since the coordinated movements of a large cluster of tadpoles can scare off a potential predator. In the time following hatching, the tadpole will grow, begin to develop hind limbs followed by front legs. In addition, the amphibians will change their physiology and diets shifting from vegetarian to carnivorous as well as develop rudimentary lungs during the time their gills begin to be absorbed.