Two species of sea slugs can pop off their heads and regrow their entire bodies from the noggin down, scientists in Japan recently discovered. This incredible feat of regeneration can be achieved in just a couple of weeks and is absolutely mind-blowing.
Scientists want to know how they do it. A new analysis reveals genetic underpinnings of how the aquatic animals regrow their heads after decapitation. For a group of small aquatic animals known as hydra, decapitation is more an inconvenience than anything else.
The Hydractinia, which grows on the shells of snails and crabs, regrows its entire head if it gets bitten off by a predator. But they aren't the only animals capable of this seemingly amazing feat: Planaria can reproduce asexually and just make copies of themselves, including newly regrown heads.
The axolotl (say "ax-oh-lot-el") is a Mexican species of salamander. It's also known as a Mexican walking fish. It can regenerate, repair or replace its arms, legs, tail, lower jaw, brain and heart.
Axolotls are commonly used in translational research due to their impressive ability to regenerate limbs, tissue and multiple organs – including the brain.
Take kangaroos, for instance. If they lose their tails, they cannot regenerate them and have to learn how to live without their “third leg,” as some scientists call it.
It seemed to have been perfectly healthy, however. So, no, crocodylians are unable to regrow limbs, but are not affected much by it.
Contrary to humans and other mammals which have limited ability to regenerate new neurons in the brain, axolotls (Ambystoma mexicanum) can regenerate the front portion of their brain (telencephalon), making them a valuable model for studying brain regeneration.
The brain actually can't regenerate itself well because when the brain is damaged its cells find it harder to make new ones. This is because the brain has very few of the special cells, or stem cells.
Cockroaches are infamous for their tenacity, and are often cited as the most likely survivors of a nuclear war. Some even claim that they can live without their heads. It turns out that these armchair exterminators (and their professional brethren) are right. Headless roaches are capable of living for weeks.
In fact, severed snake heads can still bite up to an hour or maybe even longer after decapitation. People suffer bites from decapitated venomous snakes more often than you think.
Two-headed animals also have trouble getting enough nutrients to their brains. Their divided systems can't pump enough blood to their organs. For these reasons, few polycephalic animals survive to adulthood. There are some cases of double-headed animals who lived for at least a few days, however.
Damage to the retina is the leading cause of blindness in humans, affecting millions of people around the world. Unfortunately, the retina is one of the few tissues we humans can't grow back. Unlike us, other animals such as zebrafish are able to regenerate this tissue that's so crucial to our power of sight.
Unlike some of our invertebrate and vertebrate cousins with the capacity to regenerate limbs after traumatic loss, humans do not have the ability to regrow arms or legs lost to injury or disease.
Abstract. Leg loss is a common phenomenon in spiders, and according to the species 5% to 40% of the adults can present at least one missing leg. There is no possibility of regeneration after adult moult and the animal must manage with its missing appendages until its death.
(a and b) Planarians and Hydra have the highest regenerative capacity to regenerate the whole body. (c, d, and e) Lower or primitive vertebrates, such as newt, Xenopus, and zebrafish, can regrow lost parts, such as the limb, tail, fin, or heart.
Like a starfish, an octopus can regrow lost arms. Unlike a starfish, a severed octopus arm does not regrow another octopus. But the biological secrets inside their arm regeneration feat do hold the promise of learning more about how we might better regenerate our own diseased or lost tissue.
Answer and Explanation: The bonobo (pygmy chimpanzee) is the animal that is closest in intelligence to a human being. Humans are closely related to the bonobo.
It's well known that a comatose brain can be kept alive for at least decades. That is the case with brain-dead people whose families elect to keep them attached to ventilating machines. Less well explored are artificial means of maintaining a brain wholly separated from its body.
Can axolotls live on land? No! Axolotls are strictly aquatic animals that spend their entire lives in water. They can, however, spend a short time outside of water because they can breathe air, but won't survive without water for long.
Will humans ever be able to re-grow limbs or organs? Humans have the necessary genes to build limbs and organs. As embryos we develop and grow all the limbs and organs we need! However, we don't have the ability to re-activate these genes when injuries occur.
"Saltwater crocs have the strongest recorded bite force of any animal on the planet — [the] kind of force can easily crush a human skull," Frost said.
Unfortunately, a croc's jaw has so much power that once it's locked, no amount of struggling will get it back open. Trying to pry a croc's mouth open with your hands won't work.
Over time as a species, however, we evolved past the need for such an organ, which is why the majority of humans no longer grow them. Most humans grow a tail in the womb, which disappears by eight weeks. The embryonic tail usually grows into the coccyx or the tailbone.