Healing Factor / Real Life

• Salamanders are perhaps the most complex animals capable of regenerating limbs in adulthood. One example of this is the axolotl, a neotenous salamander that can regenerate limbs and organs that were damaged or lost. They can even regenerate parts of their brains. Although it doesn't give it Immortality, it does make it live much longer. It's used as a model in biomedicine.
• There are some species of starfish that not only grow new limbs, but the detached limb can grow a new starfish!
• Sponges can be put through a fine strainer and they will eventually coalesce.
• Flatworms can regenerate bits, including heads, although it's possible to mess with this in ways that result in two-headed flatworms.
• Some round and segmented worms also can do that, but with the two-tailed and two-headed mistakes as well. It generally depends on the location and extent of the injury.
• Most leafy plants are able to regenerate from practically any damage, as long as they can still acquire nutrients and the materials needed to synthesise sugars (in other words, their roots and/or leaves still need to be at least partially functional). Many plants can be propagated simply from cuttings. In fact, for a large number of domestic fruit trees, grafting a piece of an existing tree onto an existing rootstock is the only way that they are reproduced. Moreover, using special nutrition, leafy plants may be regrown From a Single Cell.
  • As a specific example, notable even among leafy plants, willows are extraordinarily regenerative plants which actually grow more lushly if some of their limbs are hacked off; they can even regrow from piles of wood-chips. Most plants are less enthusiastic about damage. But putting a cutting from a willow in the same basin of water as a cutting from another plant can encourage the other cutting to start sprouting roots — the hormones the willow puts into the water affect the other plant too.
• There is anecdotal evidence that toddlers can regenerate fingertips that have been severed for whatever reason (not the entire finger, just the top 1/8 inch or so).
  • Supposedly, a man was able to regrow a fingertip that was cut off by applying a special powder, given to him by a researcher, to the open wound. There was a report on The BBC a while back.
    • That sounds like dehydrated Extra Cellular matrix, it's a sort of universal animal cell growth medium, by applying dehydrated stuff to the wound it re-hydrates and triggers the growth of the surrounding tissue.
• The liver in humans is said to regrow from just a third of its normally functioning tissue. This is why living-donor liver transplants are possible (although hardly easy): the donor can lose 55-70% of his or her liver and expect to have it back to near 100% functioning within six weeks, and it will be fully up to normal size and structure within two to three months.
• Blood platelets. When flesh is cut, leading to bleeding, blood platelets are life-savers. They cause blood clots (better known as scabs) along the cut, stopping the release of blood until other body functions can fix up the blood flow. This makes them sort of a pre-Healing Factor Healing Factor.
• Humans do possess the genes to regenerate limbs, however, they are heavily mutated and are considered junk DNA: Anti Heat Shock Protein 60 and Fibroblast Growth Factor 20 are in both humans and certain types of zebrafish and salamanders. Those with the mutant variants of the gene only get scarring. For the animals with the functioning genes, the cells around the wound site revert to their embryonic state and reform the lost part.
• Even without the ability to regrow lost limbs, humans still have an amazing healing ability when compared to other species. Our ability to recover from injury and our resistance to shock is absurdly high compared with other animals, and coupled with our high endurance this allows us to recover from virtually any injury that is not immediately fatal. Humans also form scar tissue at a much higher rate than any other animal on Earth, meaning a wound that might take months to heal for an animal could be healed on a human in weeks.
  • A timeline of what happens with a smoker quits is one very good piece of evidence to show just how good the human healing factor is. To put it in perspective, it takes under a year for the body to return to more or less normal function. The risk of nasty diseases will drop significantly within years.
  • It's speculated that the reason humans are unable to regenerate limbs is that having this ability would drastically increase our chances of getting cancer. Another possible reason is that the long time and massive amount of nutrition that would be needed to regenerate limbs would leave us much more vulnerable to infection and starvation than quick scarring.
• Spiders can regrow lost limbs when they molt. However, their ability to heal injuries to the torso is poor, especially in tarantulas. Many other arthropods can replace appendages during a molt as well.
• MRL mice are capable of regenerating lost tail tips and repairing organ damage... something no other mice can do.
• Sharks can heal from physical trauma remarkably quick due to a large portion of their genome being dedicated to clotting and tissue growth factors.
  • To further top it off, high levels of heavy metals that would lethal to other organisms do not seem to harm them.
• A cat's purr is not only used as a sign of happiness and contentment: it is also a means by which they can heal. Scientists believe the vibrations created from purring help to heal bones and muscles. Better still, the benefits of a cat's purr can also apply to humans.
• In 2019, a then-71 year-old woman was discovered to have an exceedingly rare genetic mutation that allowed to heal faster than normal, unable to feel pain or anxiety, and she apparently never once questioned it or thought it was abnormal. This is NOT a joke.