Why hasn't immortality evolved?

Question

Why in the grand experiment of evolution hasn't immortality evolved? Why has survival of the species taken priority over survival of the individual? Does the advantage of genetic diversity alone account for this bias for survival of the collective?

Answer 1

Evolution is all about trial and error. The best way nature has come up with to conduct such superiority experiments is via sexual reproduction. When sex happens, alleles get mixed up, in the hopes that the progeny will be more successful than the parents (assuming that at least one parent has a good allele at a locus). Since nature hasn't found the perfect combination, we're not immortal.
So what's the perfect combination? Something that would allow us to continue functioning AND enjoying life forever. Unfortunately for nature, there are increasing attacks against the human form as one ages. For example, telomeres get shortened. These are "capping" sequences at the end of chromosomes (repeating Ts) that prevent vital information from being cut off (the process of replication does not generally replicate every base at the end because polymerases need a base to start from). This means some proteins are not produced, or regulatory sequences get messed up, as one ages. This results in general breakdown of cells.
The answer above about species taking precedence over individuals is good. The chances that the particular alleles in an individual are present in the overall species population are high. So, if one individual dies, it's probably not a huge loss; in fact, it's probably better because there must have been some defect in his genes that prevented him from surviving (disregarding random stochastic events). Also, a population has a greater chance to evolve efficiently than does an individual, as there is greater diversity of alleles in a species than in a population. The population itself actually contributes to its own success over individual success, as individuals are more likely to survive if they work together. Consider animals that hunt in packs, or those that travel in herds in order to try and evade predators: in this case, it's about keeping the population alive, and the loss of a few individuals is a small price to pay for that assurance.
Genetic diversity is NOT the only factor for species preservation over individual preservation. Granted, it is a huge part, as it allows nature to tinker more with different combinations. However, stochastic events are important. These are events that have nothing to do with fitness, but rather are random, like being in the wrong place: getting shot by a human; being stuck in a tornado; falling in a crack during an earthquake, etc. Again, unless an entire pack throws itself over the edge of a cliff (as happens in lemmings with overpopulation problems, in order to avoid starving), then stochastic events negatively affect individuals, not species.
This question has to be considered in terms of humans and in terms of the rest of life. (You can argue which animals have a similar conscience; I'm going to assume that no species besides us are capable of moral judgment). The above reasoning applies well to animals. However, humans have more tools to help individuals survive. Basically, we are messing with the natural process of selection and evolution. Have you noticed that, although there are more people, more of them are ill? That's because we preserve people with bad genes and let them pass genes on to the next generation, whereas they would naturally die off and get this allele out of the gene pool. This is probably why humans won't achieve immortality in the near future - unless, of course, you count for the rapid boom in nanotechnology that may soon replace our biological components with computers.

Answer 2

Well, that was a lot of questions but:
1. Immortality hasn't developed because there have been no ndividuals in any species that have had that mutation happen to them. It's a random process.
2. Survival of the species does not actually take precedence over the survival of the individual. Only in instances of a mother/father protecting their babies does self-sacrifice to continue the species ever happen in nature. Even then, its easy to argue that it isn't necessarily a selfless protection of the species by giving up life, it's simply that the parent assumes both they and their child can survive a fight, whereas the child by themselves has no chance of survival. Ultimately, nature is all about self preservation. Mutations serve the whole species only in the long term: in the short term, the individuals with the best features will survive while the others do not. There is no precedence for the species over the individual.
3. I think i addressed that above. A species only survives if its individuals survive, and they don't sacrifice themselves for the collective.

Answer 3

Immortality may be physically, biologically, impossible. That may be the simplest reason nothing has evolved immortality yet.

But others have correctly stated the real reason. Evolution is *by definition* a process that occurs at the population level. It is a *statistical* process that requires many individuals (a population) to drive it. So survival of the individual is always secondary ... it is an advantage to the species only insofar as the individual produces more offspring. Once the individual stops producing more offspring, longevity has little purpose to evolution.

Answer 4

Death itself is an evolutionary advantage. Cell suicide is triggered by some cancer cells, for instance. Cell death on your arm buds as a foetus enabled you you have fingers.


The thing is, once you have reproduced, your genes have been passed on, they are preserved. What happens to you after that is immaterial. Many organisms die from the effort, and that is because the genes that cause this to happen also allow reproduction, and these genes will do it again, and again, and again. It is an evolutionary advantage.

All that matters is that the genes continue, that the genes are immortal. and that is what reproduction allows.

Evolution requires reproduction, if that stops, so will evolution, and that means extinction. If organisms were to stop dying, they would still reproduce, and pretty soon there will be overpopulation. Starvation and disease would finish off otherwise everlasting beings, as will competition and warfare. This is not an advantageous trait.

Even if they therefore lost the ability to reproduce, accidents, predation, disease and others would then pick off those who remain, and extinction occurs once again.

Things degrade. They run down, they cease to function, it's what happens to everything, and much of our bodies cannot be naturally replaced or maintained to the extent required. Even our very genomes degrade through our lives as the telomeres of our chromosomes shorten with each cell division. In the wild old age never gets us, it is the predators, competition and basic accidents that befall those whose bodies are no longer at peak performance.

But so long as they have already reproduced, then that's alright. The genes continue to do it again. The genes are self-perpetuating, it is their basic function, it is what drives life. The purpose of life is to keep it going, we are just protein vessels that the genes grow to enable their multiplication and preservation. This is a chemical property, not a conscious decision. Our consciousness evolved as a means to keep this up, but also allows for us to choose other goals as well, though they are often driven by the goal to reproduce.

Answer 5

Survival of the replicator takes priority. The death of the individual is nothing, when his genes are passed from generation to generation. Natural selection does nothing for the survival of species. Genetic diversity is what is selected as it stands out to be selected. The only true immortality is the immortality of the information encoded in genes. Successful genes.

Answer 6

Because there is probably no gene for immortality, whereas there are hundreds of imperfect genes which persist because they only cause death at an age where genetic material has already been passed on, and their offspring can survive without the protection of an adult.
So, anything which causes death in childhood would be selectively weeded out. Anything which causes death after about 40 years old, would probably not be weeded out. These include most cancers and heart disease.
To develop immortality, all these genes need to be eliminated in the one person. Highly unlikely when there is no selective pressure to do so.
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Answer 7

After you are done breeding (which includes raising your children to breeding age), evolution is finished with you. You're pointless after that.

Evolution consists of two processes--random mutations, and natural selection. If a mutation occurred providing immortality, what selective process would operate upon it? Immortals would have to continue having children forever for there to be an advantage. If they quit, like everyone else, there would be no selective advantage for an immortality gene. It would be as likely to disappear as anything else.

Answer 8

Another thing that hasn't been said yet...

Organic matter just doesn't last forever. Bones wear out, joints erode, skin thins. We can repair a lot, but even that process starts to lose power. Add to it natural mutations through life that make cancers more and more likely as life goes on.

Answer 9

because immortality is where god,...... jesus,......the magic donkeys,....... and the one eyed space chickens live.

Evolution is different,......... its real........