The life of a frog is a rather long one. From the time it becomes an egg, to when it sheds its skin and changes into an adult frog, there are many stages that the frog goes through. In this blog post, we will be taking a look at those three major stages in the lifecycle of a frog – from tadpole to adult.
Frogs have been around for millions of years and they’ve changed very little. They are a good indicator to see how the environment is changing because they’re sensitive creatures who live in natural habitats, so changes can be easily seen.
What are frogs?
Frogs are classified as amphibians in the animal world. The term “amphibian” refers to a creature that lives in two places at once. Frogs are found all over the world and are one of the most diverse animals on the planet, with over 6,000 different species.
Frogs require water to procreate, yet they can be found on every continent except Antarctica and in practically any climate. Amphibians are fascinating animals that live part of their lives in the water and part of their lives on land.
The majority of frogs are carnivores with sticky tongues that help them catch their food. They swallow it fully after that. Insects are one of the preferred foods of frogs.
Colors of frogs
Frogs and toads exist in over 3,000 different species, and they exist in every hue of the rainbow. Frogs are most commonly found in hues of green and murky brown, which help them blend in with their environment.
Some frogs, like reptiles, can change their color in response to light, temperature, humidity, or even mood. Many frogs and toads turn pale in fear or excitement, but others, such as the African clawed frog, get darker when startled.
Chromophores, a type of pigment cell, are responsible for such color shifts. Color variations are caused by pigment granules altering their distribution inside these cells. The frog is light-colored when the grains are packed together in the center of each cell. The frog’s color darkens and strengthens as the pigment grains spread out throughout each cell.
Lifecycle of a frog
The life of a frog is one that is full of adventure and discovery.
The Egg is the first stage of a frog’s life cycle. A frog’s existence begins with a fertilized egg. A female frog lays a large number of eggs (thousands at once) in or near water.
Frogs lay their eggs on water surfaces in huge, spherical clusters, but toads attach their eggs to grass or plants along water borders in long parallel threads that resemble strands of black beads.
Frog embryos appear as black specks in the center of clear gel-like blobs. This jelly layer serves to increase their size (so they won’t be eaten as easily), protect them from germs, and attract and activate sperm.
Frog eggs can take anywhere from three to 25 days to hatch after being laid.
A tadpole is a phase of the lifecycle of frogs and other amphibians. The tadpole is the “larval stage” and this phase lasts about 14 weeks.
Larvae, or larvas, are a stage in the development of many animals that occurs after birth or hatching but before they reach adulthood. A tadpole spends virtually all of its time in the water.
Tadpoles are herbivores that eat planktonic material in the water. They enjoy feasting on sediment and scraping material from underwater surfaces like stones or plants.
Tadpole predators include raccoons, water snakes, tiny alligators, and crocodiles, as well as predatory birds such as herons and fish.
When faced with the possibility of attack, tadpoles will restrict their foraging activity; there is a balance between the competing needs to grow as quickly as possible and avoid being eaten by predators. Some species may use schooling behavior to maximize food intake while minimizing predation.
Later in the tadpole cycle, the tadpole develops two hind legs as well as a lengthy body and head. Instead of swimming, it can effortlessly bounce around with the help of its two rear legs.
The tadpole is virtually fully grown when it reaches the froglet stage. The tadpole’s gills have vanished, and its lungs have grown larger at this point. This indicates that it is prepared to move from the water and dwell on land. It will become an adult frog once its tail has vanished.
Frogs can survive on damp ground or in shallow still water, and they can quickly switch between the two during the transition from froglet to fully grown adult frog.
During the winter, adult frogs hibernate. The frog’s essential organs have a high quantity of glucose, which prevents them from freezing. A half-frozen frog’s heart will stop beating and its respiration will halt. It will look lifeless. The frog’s frozen sections will thaw as its shelter warms above freezing, and its heart and lungs will resume normal function.
Predators abound for frogs; birds, fish, and reptiles all prey on frogs. Most rainforest frogs have sticky hair pads on their fingers and toes, as well as loose sticky skin on their bellies, which make them excellent climbers.
Frogs love to dine on any of the following creepy crawlers:
- brine shrimp
Surprisingly, frogs may also eat waste and debris floating in the water, but only when the occasion arises. Frogs, lizards, and even tiny mammals like mice are eaten by larger species of frogs.
Frogs have a variety of defenses, including the secretion of poisonous substances.
Poison frogs, also known as poison arrow frogs and poison dart frogs are the world’s most colorful frogs. They inhabit Central and South America’s moist, tropical jungles, where their food contributes to the poisons they produce via their skin. In fact, the average wild golden poison frog produces enough poison to kill ten humans.
Other frog defenses include:
- Playing dead
- Jumping away
- Making sounds
- Puffing up or appearing larger
- Using camouflage
- Urinating while jumping away
- Screaming to scare away potential predators
The Goliath frog is the largest, measuring 13.5 inches (30 cm) in length and weighing 6.6 pounds (3 kilograms).
Frogs are known for their incredible jumping abilities, but the African frog is the finest of them all. According to the San Diego Zoo, it can leap 14 feet (4.2 meters) in a single bound.
Climbing atop the female’s back, the male clasps his forelegs around her midsection in the act of sexual reproduction.
The male and female adopt a mating posture known as amplexus to ensure that the sperm reach the eggs. Amplexus aims to align the cloacae in general. The cloaca is the hole through which males and females release sperm and eggs, and the closer they are, the more successful fertilization becomes.
Frogs can continue in amplexus for hours or even days, depending on whether the female releases one or hundreds of eggs.
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Ovulation and sperm maturation are seasonal. Frogs produce sperm over the summer, and by the time they hibernate in the fall, they have all of the sperm they’ll need for the next spring’s breeding season.
Frogs can reproduce sexually, but only externally. The female deposits eggs, which the male fertilizes externally by squirting sperm into the water.
Frogs reach sexual maturity around the age of four. From February through March, they emerge from hibernation to look for nesting areas.
Tadpoles require roughly 40 days to hatch from their eggs and the life cycle journey of tadpole to frog begins all over again!