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Our closest worm kin regrow body parts, raising hopes of regeneration in humans

washington.edu

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Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#131

Post by aquadrop »

coldtea wrote: post #104
toasterlovin wrote: post #90

Earlier quoted context omitted.

Living for a long time after you have children is incredibly useful from the standpoint of genetic fitness. After all, grandparents play an important role in pretty much every human culture. And a grandparent with all their body parts is a whole lot more useful than one without.

> Living for a long time after you have children is incredibly useful from the standpoint of genetic fitness. After all, grandparents play an important role in pretty much every human culture. In the time scale that matters to evolution, grandparents played absolutely no role for the Homo Sapiens, and neither did culture.

In many historic cultures, 'elders' were the ones who controlled the tribe.

Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#132

Post by nostoc »

xux wrote: post #74

A lot of people are focusing on the mechanics, but it seems like humans don't generate body parts just like cells don't generate organelles. The entity is not _meant_ to exist by itself, but form a cohesive living group. A cell doesn't need to repair itself, it can simply clone itself and then die. A human being doesn't need to regenerate itself because it can reproduce and be cleared away. Evolution evolved to ensur…

The specie as the unit of selection is an idea that is very unpopular in the biological community. A lot of people believe instead that evolution works first and foremost at the gene level, and that gene selection is the driving factor for evolution.

https://en.m.wikipedia.org/wiki/Unit_of_selection

Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#133

Post by skriticos2 »

ogrisel wrote: post #122
haywirez wrote: post #102

Earlier quoted context omitted.

> Evolution evolved to ensure the survival of the species, not the individual. Depending on which view you take, evolution can be seen optimized for the survival of individual genes, not species[0]. In Dawkins' book, bodies are portrayed as mere useful survival vehicles for various genes. (I'm ignorant on this, would love to read counterarguments from someone better versed!) [0] https://en.wikipedia.org/wiki/Gene-cen…

Indeed virii are part of the evolutionary process and can insert genes into hosts from various species. Such genes can be successful from an evolutionary standpoint even if some of the host species disappear.

Not contradicting your core argument (though I'm sceptical about the significance in impact of this process), but you are certainly apt at mutating grammar: the plural of virus is viruses - not virii.

http://english.stackexchange.com/questions/3838/viruses-or-v...

ps: this is like kerning, you can't unsee it..

http://xkcd.com/1015/

Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#134

Post by csomar »

xux wrote: post #74

A lot of people are focusing on the mechanics, but it seems like humans don't generate body parts just like cells don't generate organelles. The entity is not _meant_ to exist by itself, but form a cohesive living group. A cell doesn't need to repair itself, it can simply clone itself and then die. A human being doesn't need to regenerate itself because it can reproduce and be cleared away. Evolution evolved to ensur…

I think the difference in the 21 century is increased awareness of consciousness. Unconscious animals don't care about survival of their own self. They just reproduce.

Humans, since getting a bit of self-awareness have been fantasizing with the idea. Religion, and self-rebirth after death is an example.

Now they are getting more real and more practical. If you think about it, it makes more sense to increase your lifetime than make another person to carry-on your dreams.

Your emotions tell you otherwise, because you were made to reproduce. The brain is working something else. It's evolving and thinks that it can solve this problem and instead re-make the body.

Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#135

Post by aninhumer »

Turing_Machine wrote: post #70
avodonosov wrote: post #35

It would be good to regenerate at least teeth.

Teeth might also be a good area to look at in terms of figuring out how it works. Since most people already grow two full sets of teeth, and I believe there are numerous cases on record of people who have grown more than that, perhaps the regeneration genes are already partially activated in that region of the body.

I'm not a dentist, but I get the impression that milk teeth and adult teeth are different things, not a regeneration cycle?

Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#136

Post by michaelscott »

JumpCrisscross wrote: post #72
marvy wrote: post #68

Earlier quoted context omitted.

The same way you police it in a dictatorship, or any other form of government. Just do what China does for its one child policy, except that it would be a zero child policy. I doubt this is a good idea though.

> I doubt this is a good idea though I agree. Overpopulation is an overstated problem [1]. Rich societies reproduce at below their replacement levels. Pursuing higher quality of life by expanding capability (including by tapping extraterrestrial potential) is more sustainable than by constraining population. [1] http://www.nytimes.com/2013/09/14/opinion/overpopulation-is-...

But this happens because we don't live very long currently. So we prioritise using the time we have to build material resources so that when (if) we have a child we can maintain standard of living.

If you were assured to live even 100 years you could spend the first 50 creating a high standard of living and the next 50 raising children within that standard.

Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#137

Post by lordnacho »

dharma1 wrote: post #125
mattnewton wrote: post #27

Earlier quoted context omitted.

Maybe that's the ticket? The cancer resistance is something that allows the axolotl to also keep regrowing limbs around in the genome?

There are also many animals who are long living, and immune to cancer (to varying degrees). Naked mole rats live up to 30 years and almost never get cancer (only one case formally verified so far). Elephants have many more cells than us, and live to almost the same age, but only have a 5% chance of getting cancer, vs 10%-25% in humans. Lions have a 2% chance of getting cancer.

Out of curiosity, how do we know the cancer rates of various animals?

Someone would have had to examine a lot dead animals of various species to figure this out.

Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#138

Post by anshou- »

PeterisP wrote: post #2

Well, a plausible answer is that if we (or random mutations) re-enable those genes then the end result is simply a lot of cancer. A reasonable default assumption is that each switch in our "genetic configuration" is set to a quite good value. The only exception is if we see a feature that is beneficial at a high calorie cost - those features have been (reasonably) optimized away during our evolution, but would be use…

Maybe. The elephants being born without tusks due to ivory hunting pressures changing reproduction dynamics are likely at a disadvantage overall, but in the short term they will survive. Having tusks may be objectively better, but right now it'll get you killed.

Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#139

Post by bradyd »

Ygg2 wrote: post #11
awqrre wrote: post #5

Earlier quoted context omitted.

if you got cancer, just cut that piece off and eat more?

Yeah, just regrow that brain, liver, thyroid gland. It could be those genes raise chance of cancer everywhere. Not just limbs.

The liver can regenerate. As little of 25% of the original liver mass can regenerate back to full size after either surgical removal or chemical injury.[1]

[1] https://en.wikipedia.org/wiki/Liver_regeneration

Re: Our closest worm kin regrow body parts, raising hopes of regeneration in humans

#140

Post by Asooka »

aninhumer wrote: post #135
Turing_Machine wrote: post #70

Earlier quoted context omitted.

Teeth might also be a good area to look at in terms of figuring out how it works. Since most people already grow two full sets of teeth, and I believe there are numerous cases on record of people who have grown more than that, perhaps the regeneration genes are already partially activated in that region of the body.

I'm not a dentist, but I get the impression that milk teeth and adult teeth are different things, not a regeneration cycle?

Yep. If you're morbidly curious, you can google "baby skulls" (unsettling on so many levels, to be honest) to see how we're all born with TWO sets of teeth in our jaws. One just falls off as the ones above them push them out.
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