Do you like frogs? Many kids love to see these tiny creatures hopping around the backyard or a local pond. They’re even fun to catch and keep as a pet. One of the most interesting things about frogs, though, is how they begin their lives.
A mother frog doesn’t give birth to a live baby frog that looks like a miniature version of a regular frog. Instead, she lays eggs that — if they’re lucky — may one day turn into a frog.
Like caterpillars that become beautiful butterflies, frog eggs undergo a similar metamorphosis. Eggs that hatch in the water transform from aquatic tadpoles into air-breathing frogs that can live on land.
Tadpoles are sometimes known by other names, such as pollywogs, porwigles or pinkwinks. The word “tadpole” comes from the Middle English word taddepol, which is made up of the words tadde (“toad”) and pol (“head”).
After hatching from their eggs, tadpoles stay hidden for a while until their gills and muscles begin to grow. Early on, they’re very fragile creatures.
Over time, tadpoles learn to swim and breathe through their gills. Their chubby bodies and long tails don’t look anything like the frogs they will eventually become, though.
As youngsters, tadpoles scrape algae from plants and rocks. As they grow and get older, their gills start to recede into their bodies. Legs develop first, followed by arms. Their tails also begin to shrink and they start to eat dead insects and plants in addition to algae.
When their lungs develop fully, tadpoles can leave the water and live on land as a new frog. New frogs — sometimes called froglets — may have a stubby tail for a little while, but it eventually disappears.
So how long does this process take? Scientists estimate the total transformation from tadpole to frog takes approximately 12-16 weeks most of the time. However, in cold places or at high altitudes, the tadpole to frog metamorphosis can take an entire winter.