While some may consider the ability to regrow limbs a superpower, there are animals that do regrow limbs regularly.
Some animals may choose to remove a limb themselves as a way to survive.
The world is inhabited by creatures with incredible capabilities.
25 Animals That Can Regrow Limbs
While some animals may use their extra limb as nutrient storage, others will use their limbs as a distraction for predators.
Not every limb removal is painful or out of fear.
Sometimes, it is simply just another natural process that animals go through.
All of these animals have their own tricks up their sleeves.
Axolotls are the adorable, aquatic salamander that lives exclusively in Lake Xochimilco near Mexico City.
Axolotls are being studied around the world for their extreme ability to regrow limbs.
According to Harvard University, they are also capable of regrowing their spinal cord, heart, and other organs.
The limb regrowth process starts with initial trauma or when the limb is removed.
The damaged limb quickly grows muscle and skin around the open wound to close it and cartilage grows on the end of any damaged bones.
Stem cells gather towards the end of the limb, extending it and allowing for the creation of more muscle, skin, and cartilage.
The cartilage will grow in a similar way to how the bone was as the stem cells extend out further.
When the stem cells quit growing outwardly and the cartilage has turned to bone, then the regrowth process is complete.
Although they may not be as extreme as the axolotl, deer have regenerative qualities.
Deer are capable of regrowing their antlers if they lose them.
Deer can lose their antlers by fighting their other deer, getting shot at, or even having them get too big.
Deer can regrow their antlers thanks to their nutritional diet, which is packed with calcium and phosphorus.
They eat grass, insects, berries, nuts, and whatever other foliage they find.
Studies have also found that genetics play a large role in how quickly a deer can regrow its antlers.
If the father has large antlers, then the offspring are going to be able to grow large antlers and regrow their antlers faster.
Starfish are well known for their ability to regrow limbs.
While most starfish need their center to remain intact, others can grow brand-new bodies from severed limbs.
All of the vital organs that starfish need in order to survive are located in each of their arms.
Another feature that starfish have that makes it much easier for them to survive being torn apart is the fact that starfish lack blood or a brain.
These brainless creatures can live for up to 35 years.
Starfish eat their prey by suctioning onto them and then having their stomachs exit through their mouth to digest food.
When they’re done eating, they put their stomachs back in their mouths.
4. Green Iguana
Green Iguanas will remove their tails whenever they are feeling threatened.
Those who own these green giants may have found their iguana’s tail twitching on the ground or even have them pop off in their hands.
If you are looking to avoid this happening, you will want to make your iguana as comfortable as possible.
When an iguana’s tail grows back, it is rarely ever the same color.
More often, the tail grows back a darker shade or even gray and black.
Younger iguanas are more capable of regrowing their tails.
Older iguanas may choose to not use the energy to regrow their tail, instead choosing to grow in size.
5. Sea Cucumber
Sea cucumbers may be one of the most simple-looking creatures in the ocean, but their ability to regrow organs is seen as some of the best regrowth in the animal kingdom.
It only takes four weeks for sea cucumber to heal from a three- to five-millimeter cut along the body wall.
Sea cucumbers use special cells called morula cells in order to patch up any holes they may have.
Over the course of the four weeks, these cells are replaced by muscle, nerves, and flesh.
Sea cucumbers are almost alien in their odd capabilities.
Their strangeness only begins at their limb and organ regrowth abilities.
Sea cucumbers have tentacles that surround their mouths in order to capture plankton.
Their mouths are only used for eating.
Breathing is done through their anus, which is also where small fish like to hide from larger prey.
Alligators are reptiles, and many reptiles are able to regrow their limbs.
Whether or not alligators could regrow their limbs was called into question by scientists.
Because of their massive size, alligators have a harder time growing their large limbs, but they are able to do it.
Alligators can’t regrow bone or skeletal muscle, but they can still regrow the cartilage, connective tissue, and skin.
Most alligators that lose their tails don’t ever grow their tails back out to their former glory.
They have been seen with small, deformed tails once they have grown back.
The tail’s tip is often elongated, and the scales are much smaller than usual.
7. Mexican Tetra
The Mexican tetra is a river fish from Northern Mexico that can regenerate heart tissue.
Scientists are currently studying how the Mexican tetra is able to self-heal its heart.
They want to apply their findings to help prevent heart failure.
There are two different types of Mexican tetra: river-dwelling and cave-dwelling.
Only the river-dwelling tetra can regenerate heart tissue.
The cave-dwelling Mexican tetras have lost their eyes due to generations of these fish living deep in water caves where there is no light.
For some unknown reason, cave-dwelling tetras have also lost the ability to self-heal their hearts.
The two different types of Mexican tetra will often interbreed, but the ones that are born in caves will not have eyes.
Despite their eyeless look, the cave-dwelling tetras aren’t blind.
Instead, they use their pineal gland to detect light.
8. Five-Lined Skink
Similar to the green iguana, the five-lined skink will drop its tail to use it as a distraction for predators that are pursuing them.
There is a certain point in their vertebrae called a fracture plane.
The surrounding muscles seal the hole quickly to prevent the skink from bleeding out.
Skinks that have too small of a tail when winter arrives won’t make it until spring because all the fats that are stored in their tail are lost when they drop their tail.
If a skink’s tail doesn’t grow back properly or is big enough, then they may have a difficult time finding a mate.
Skinks can only regrow their tails once in their life.
Just like the Mexican tetra, the zebrafish is able to regenerate its heart, even after having serious heart injuries or amputations.
The zebrafish is able to heal its own heart without much scarring thanks to all of the collagen and collagenolytic growth that happens during the healing process.
Scientists are also using zebrafish for genetic and developmental studies.
Zebrafish have transparent eggs that are easy to study and manipulate.
Zebrafish are able to model Alzheimer’s disease, congenital heart disease, polycystic kidney disease, and even some types of cancer.
These fish have been extremely beneficial for testing treatments for influenza and have helped scientists understand the mechanisms of tuberculosis.
Zebrafish have even been sent to space in the name of research.
Crayfish are tiny yet mighty arthropods that are able to regrow their claws.
It takes one molt in order for crayfish to fully regrow their claws.
Crayfish are also able to regenerate the neurons necessary for brain activity.
Scientists are hoping to apply what they have learned from crayfish to the human medical field.
Crayfish are found all over the world, with 540 different species.
They can be found in any body of freshwater, like rivers, ponds, lakes, and even small streams.
Crayfish are so interesting and so diverse that they have their own field of scientific study, astacology.
While conches are best known for the way their empty shells mimic the sounds of the ocean waves hitting the shore, conches are able to do some interesting things while they’re still inside their shells as well.
Conches are able to regenerate their eyes in a matter of weeks.
The conch is also capable of producing pearls that come in shades of white, brown, orange, and pink.
Queen conches live for about seven years, but other species have lived as long as 20 to 30 years.
The older a conch is, the thicker its shell will be.
Flatworms are interesting creatures that can multiply by being split up into pieces.
Flatworms have incredibly powerful stem cells that allow them to regrow entire bodies from a single part of their body.
Each body part that regrows into an entire worm is a clone of the original worm.
Flatworms have a special kind of stem cell called pluripotent stem cells, which take up one-fifth of their bodies.
This is why they are able to regrow from any body part.
Humans have pluripotent stem cells, but they only appear in the embryonic stage.
We lose all pluripotent stem cells before we’re born.
13. Sea Squirt
Sea squirts, also known as tunicates, are able to regrow their entire body from just blood vessel fragments.
It only takes a week for a tunicate to regrow its body.
The majority of blood vessel fragments that are left behind from an attack on a sea squirt will regrow into an adult sea squirt within one to three weeks.
Sea squirts use the water that flows through them to get all the oxygen and nutrients that they need.
Their diet consists of plankton and small remains of dead sea creatures.
Tunicates act as vacuums for the ocean floor.
Jellyfish are able to rebirth themselves after they die thanks to their regenerative properties.
When a jellyfish dies and begins to decay, the jellyfish regenerates into polyps that attach to the decaying body.
Once the polyps are ready, new jellyfish burst from them and the cycle begins anew.
Normally, jellyfish start as larvae, and those larvae attach themselves to rocks and ships to become polyps.
By regenerating from a decaying jellyfish, the future jellyfish skip the larval stage.
Both the immortal jellyfish and the moon jellyfish are able to rise from their ashes like a phoenix.
Cockroaches could live through just about any dangerous situation, even losing their heads.
Although cockroaches can’t regrow their heads, they are capable of regrowing limbs.
The younger the cockroach is, the better it will be able to regrow its limbs.
Without their heads, both the head and the body can survive for weeks, but eventually, the lack of a body or head will kill the cockroach.
Cockroaches will shed their legs out of fear or in order to escape.
Chameleons have a few unique talents.
While chameleons are best known for their ability to change colors, they are also able to regrow their limbs.
Chameleons can grow back their tails, limbs, and even jaws.
Chameleons use pluripotent stem cells to grow the complex tissues and muscular structures that make up their body parts.
They can heal their nerves and skin when regrowing back amputated limbs.
Chameleons use their color-changing ability for more than just camouflage.
They also use it to communicate with other chameleons and to help regulate their body temperature.
Thanks to spiders’ exoskeletons, they are able to regrow their limbs should they need to.
Unlike many lizards, spiders can’t regrow their limbs right away, and it isn’t always possible.
Spiders have one molt to regrow lost limbs.
Spiders can regrow their legs, mouthpieces, pedipalps, and silk spinners.
Although spiders can regrow these parts of their bodies, newer limbs are often much smaller or thinner than the rest of their body.
Spiders that are done molting will not be able to regrow the limbs they’ve lost.
In a spider’s life, it will only molt 20 times before it is fully mature.
Each shedding of a spider’s exoskeleton is known as an “instar”.
Similar to the mythical creature, hydras are tiny creatures that are capable of splitting their two heads into clones of the original hydra.
Hydras replace every single one of their cells every 20 days, making them seem ageless.
The hydra’s ability to regenerate so quickly comes from the fact that half of their bodies are stem cells.
Through these stem cells, hydras have unlocked non-senescence, which is essentially biological immortality.
Hydras are best known as pests that are incredibly difficult to get rid of.
They are especially a nuisance for fish breeders and outdoor aquarium owners.
They are prone to killing off baby fish who are fresh out of their eggs.
19. Sea Slug
Sea slugs are able to regenerate their entire bodies from just their heads.
Their heads are even able to live independently of their bodies thanks to their plant-like ability to photosynthesize.
There are occasions when the sea slug will simply decide to detach its head from its body.
Sea slugs are able to photosynthesize thanks to all of the algae they eat.
Their bodies can live for months without their head.
In three weeks, a sea slug can regenerate 80% of its body.
The bodies that they regenerate are identical to their previous bodies.
Tadpoles may lose their tails when they grow into adult frogs, but if a tadpole loses its tail before it loses the ability to have a tail, it can regrow it.
Younger creatures will always have more stem cells than older ones, and the same is true of frogs and tadpoles.
During a frog’s early life as a tadpole, it will go through many changes.
All of the stem cells in its body rapidly change the shape and abilities of the tadpole.
They have special stem cells in their skin called Regeneration-Organizing cells.
Tadpoles show just how powerful stem cells can be and how massive of a change they can make in a creature’s body.
Octopuses are some of the smartest animals on the planet.
They aren’t just intelligent and resourceful, but they can also grow back limbs.
Their limbs are active for an hour after they have been amputated from the host.
They’ll even try to pick food off the ground and attempt to feed the area where the octopus’s mouth should be.
It takes an octopus a much longer to regrow its limbs than most lizards.
A fully functional tentacle takes about 100 days to regrow.
While reptiles will regrow lesser versions of their previous limbs, an octopus will regrow its tentacle back better than whatever it was before.
In the same way that zebrafish can regenerate their hearts, catfish can regenerate their barbels, or more commonly known as their whiskers.
These two fish share similar collagenolytic growth.
Although the barbels may look like whiskers, they are actually appendages that help catfish detect food.
There are more than 2,900 different species of catfish that range from sizes of a couple of feet to more than eight feet long.
Unlike most fish, catfish don’t have scales.
Instead, they have bony plates.
Geckos can grow their tails faster than any other lizards, taking only 30 days to regrow their new tails.
Not only are geckos able to regrow the tissue and skin of their old tail, but they are also able to reform their spinal cord that goes all the way down their tail.
However, scarring happens after the new tail is formed, preventing the gecko from regrowing another tail.
In the wild, this leaves geckos extremely vulnerable.
Newts, like axolotls, are able to regenerate their limbs with ease.
They use skeletal muscle fiber cells and muscle stem progenitor cells to regenerate their limbs.
Newts are also able to regenerate their spinal cords, hearts, eyes, intestines, and jaws.
Newts are also able to release toxins from their bodies as a self-defense mechanism.
While baby newts are often eaten by fish, adult newts have to hide from foxes and herons.
25. Kemp’s Spiny Mouse
While lizards may shed their tails in order to distract predators, the Kemp’s spiny mouse will shed its skin in an attempt to run away.
The spiny mouse can grow its skin with fur and without any scarring.
They form clumps of cells called blastema all over their exposed flesh to grow new skin.
When scientists would attempt to grab spiny mice, they were often left with just a clump of skin in their hands.
The spiny mouse uses its skin like a banana peel and is the only mammal known to do so.