I have been thinking a lot about regeneration. While it is common knowledge, it still amazes me, that salamanders can regenerate body parts, including their tails, upper and lower jaws, eyes and hearts. Yet mammals including humans can’t. Salamanders are the highest order of animals capable of regeneration. Do mammals know something that salamanders don’t? Cosmetic surgery, implants, and promising regenerative medicine research aside we humans are stuck with the body parts we are dealt for now.
I wonder if our inability to regenerate at the biological scale also impedes our ability to regenerate at a social system scale. It seems obvious that our important social systems including education, healthcare, and public services need serious regeneration. These systems have evolved over a long period of time, were built to support an industrial era that is long gone, and have built up incredible mechanisms to resist and prevent needed change. It is not technology that is getting in the way of social system change. It is humans and the organizations we live in that are both stubbornly resistant to change. Why are humans so incapable of regeneration at both biological and social scales?
Maybe understanding the biology of regeneration can provide insight. Salamanders can regenerate injured body parts because evolution has enabled them to immediately unleash stem-like cells to a wound site when damage is detected. When salamanders are wounded skin, bone, muscle, and blood vessels at the site revert to their undifferentiated state. In essence they go back to an embryonic state and start all over again making regeneration possible. Humans took a different evolutionary path.
Turns out the human evolutionary pathway traded-off regeneration in favor of tumor suppression. In order to decrease the risk of cancer and increase longevity our mammalian ancestors selected against regeneration. The theory is that the rapid cell division required for regeneration looks to our bodies a lot like the unchecked growth of cancer. Because our longevity makes us vulnerable to accumulated DNA mutations we’ve evolved a kind of molecular brake to keep tumors at bay. I can’t speak for humankind but it seems like the right trade-off to me. Unlike salamanders, when mammals injure or lose a limb the body’s reaction is to release cells to the site…