With so many fascinating metamorphic changes, amphibians flaunt a wide range of physical features throughout their lives. This has led to plenty of confusion surrounding their development, and many animal lovers wonder if frogs have tails.
Frogs have tails as tadpoles, as they are fully aquatic and need tails to swim during this time. However, frogs lose their tail which is absorbed into their body as they metamorph into froglets and prepare for life on land. Juvenile frogs grow legs and have no tail by the time they reach maturity.
Frogs do not have tails as adults, which is one of the main reasons why these frogs are classified as Anura. The term ‘Anura’ can be translated to ‘without tail’ or ‘no tail’. However, while frogs generally do not have tails, they are not tailless throughout their entire lives.
Although frogs do not have tails as adults, they still need tails to survive in their habitats when they are young. Join me as I discuss the necessity for frogs to have tails as tadpoles, and how their physical structure develops into what we know as adult frogs.
Are Frogs Born With Tails?
Frogs are not born with a tail since many frogs are born in water in jelly-like eggs. However, the eggs typically develop into young tadpoles with tails after 2 to 3 days. Tadpoles generally develop into young frogs that then absorb the tail into their bodies over a 16 week period.
The thyroid hormone triggers the metamorphic change from frog egg to tadpole, typically taking around 3 to 25 days, depending on the species and climate. Once zygotes begin to transform into tadpoles, otherwise known as polliwogs, various interesting physical adaptations begin to take place.
Also referred to as the frog larval phase, tadpoles usually measure at around 40 to 45mm on average. The developmental process typically takes 14 to 16 weeks, depending on the environment and frog species. Tadpoles generally have internal and external gills, bodies, and tails (CTNF).
|Tadpole Phase||Physical Development|
|Early||Breathe through the skin while tails and gills are developing|
|Middle||Short oval bodies, tiny mouths, gills, and long wide tails|
|End||Beginning of apoptosis, where the tail begins to disappear|
The hind and front legs start forming
In addition to lungs and other classic frog features
Tadpoles need their tail because fogs typically lay their fertilized eggs in water, meaning that the zygotes will transform into tadpoles that will need to survive in aquatic spaces. This sort of lifestyle means that tails are incredibly essential for tadpoles, allowing them to swim around like schools of fish as they feed on nearby aquatic vegetation such as algae.
As the tadpole phase draws to a close, they begin to grow hind and front legs to be able to live on land. Their tails become shorter as they disappear due to a process called apoptosis, otherwise known as cell death. After this point, the tadpoles will begin forming other features for life on land, such as lungs.
When Do Frogs Lose Their Tails?
Frogs generally lose their tails 22 to 25 weeks after being born, depending on the species and environment. Froglets generally still have short tails or stumps, as they will continue to lose more of their tail by apoptosis as time progresses.
|Metamorphic Phase||Common Name||Tail Development Status||Average Duration|
|Zygote||Frog Egg||Physical features are still developing.||3 to 25 days|
|Tadpole||Polliwog||Tadpoles have long tails.||14 to 16 weeks|
|Juvenile Frog||Froglet||The tail becomes shorter over time.||6 to 9 weeks|
|Mature Frog||Frog||The tail disappears entirely.||2 to 4 years|
Since froglets are not yet ready to live on land, they still need the necessary features to survive in aquatic areas. During this phase, they develop lungs and legs, but they cannot remain on land for lengthened timeframes.
Froglets generally return to water frequently, and a steady transition from using their tails to using their legs helps them adjust as they age. They still need some time to practice using their legs to swim and evade predators as opposed to using their tails.
The journey from froglet to frog typically takes approximately 6 to 9 weeks, depending on the species, climate, and overall environment. After this point, they are classified as frogs, and they would have generally lost their tails entirely once they become adults. That being said, it still takes around 2 to 4 years for frogs to reach full maturity.
Why Do Frogs Lose Their Tails?
Since most frogs do not live a fully aquatic life, they do not need to keep their tails as they age. In addition, frogs would not be able to survive on land only equipped with a tail.
Although frogs will still need to swim and roam aquatic spaces into adulthood, they can also use their legs for these purposes. Aquatic frog species and many other types of frogs generally develop webbed feet to assist their semi-aquatic lifestyles, defeating the initial purpose of tails.
All frogs lose their tail and develop legs and lungs during metamorphosis. Some mature-appearing froglets may take slightly longer to lose their tails entirely, which can cause some confusion. These froglets may still have short tail stumps. But, this is still natural and healthy, and the froglet tail will be absorbed into their body over time.
Contrary to popular belief, frogs’ tails do not simply fall off. Instead, it is absorbed into the body, allowing other functions and processes to take place.
Tailed Frogs Do Not Have Tails
The ‘Tailed Frog’ often causes perplexion in animal lovers and amphibian enthusiasts, as these creatures appear to have tails, as the name suggests. Tailed Frogs belong to the Ascaphidae family, under the Ascaphus genus, and comprise two species (Ascaphus Montanus and Ascaphus Truei).
However, these Tailed Frogs are not tailed at all, as the body part that resembles a tail is actually an extension of the male cloaca. The purpose of this extension is to minimize sperm loss during breeding, as the species often inhabits fast-flowing streams. Therefore, this physical feature is only found in males, while females flaunt a physical structure similar to most other frog species (CTNF).
Although one may observe a frog that appears to have a tail, it is more likely due to varying physical features or delayed apoptosis. All frogs lose their tails over time, as they adapt to living on land and in water using their legs and new bodily components.
More About The Frog Life Cycle
Find out more about the frog life cycle on our blog in the following articles:
- Frog Anatomy
- Frog Reproduction
- Frog Longevity
- How Do Frogs Mate?
- When Do Frogs Mate?
- Why do Frogs Release Large Numbers of Eggs?
- Frog Eggs: Everything There is to Know
- Do Frogs Lay Eggs?
Common Questions About Frog Tails
Does a tadpole’s tail fall off? Contrary to popular belief, a tadpole’s tail does not fall off. Instead, it is absorbed into the body due to a process called apoptosis allowing for the frog to live on land.
What is a frog with a tail called? Frogs do not have tails and are classified under the order of Anura (without a tail). Therefore, a frog with a tail may be at the tadpole stage and can be referred to as a tadpole or young frog. It may also be a salamander or caecilian.
Why do frogs lose their tail? Frogs lose their tail to be able to live on land as adults. Most frogs do not remain fully aquatic after they grow past the tadpole stage, and they therefore do not need to keep their tail as they age.