if natural selection theory is correct, then why does species die by age?, i mean, there isn't ANY advantage for an species to be mortal; more years to live mean more oportunities to generate offspring and therefore, there is a much larger probability to survive in the future. a species that doesn't die because of age would dominate the world undoubtedly
Evolutionary advantages go as far as your chemical setup lets you. Sure natural instincts would dictate you to live longer but thats physically not possible
>>8017113
We've already fucked a lot by the time the things that makes us die kill us. It isn't selected against.
>>8017127
i've learning that death by aging is somehow programed in our DNA.
>>8017113
>i mean, there isn't ANY advantage for an species to be mortal;
Bullshit.
The old must make way for the new.
A species can't change and adapt without older individuals dying out.
>>8017138
What you've learned is popsci shit. Biological damage caused by aging might have roots in our DNA but we're not even close to knowing the exact mechanism.
>>8017138
not exactly. Our body oxidizes with each breathe we take. The oxygen slowly decays the organs and our body parts. DNA is actually programmed to re-new itself but it can keept it up for so long.
>>8017113
This is clearly b8 but I'll bite: dying of age isn't an *unfavorable* trait, since most organisms are able to pass on their genes before succumbing to aging or something else.
If immortality was favorable over mortality, the Hydra and other cnidarians would have taken over the biosphere by now.
>>8017142
if death is the result of all the damage we have received from the environment, how can you explain that there actually exist species that dont age such as the jellyfish "turrutropsis nutricula"(or something like that)?
>>8017150
> more years to live mean more oportunities to generate offspring
>>8017161
Natural selection weeds out unfavourable traits, it isn't a perfectionist working "towards" something. Also it's random. Maybe a live longer and still be able to produce spring didn't happen, or something.
>>8017161
>this is how creationists actually think natural selection works
>>8017167
yeah, i thought the same, even though it seems pretty weird to me that evolution created wings, lungs, eyes, even inteligence and consiousness before inmortal vertebrates...
>>8017176
it sounds pretty logical to me, is there any counter-argument you could have? thanks.
>>8017113
Your assumption that all species die by age is false. Prokaryotes do not die by old age, they replicate en masse and have a lovely time of it. What you are discounting is how difficult it is to make a complex multi cellular organism. As other posters have stated these creatures slowly gain genetic damage and their cells are unable to reproduce. Cancer is an easy way to observe such failure, aprox. 10 mutation pop up in one of the billions of cells you have that prevents cell death and increases growth rate. These cells can be considered functionally immortal but they are riddled with defects that propagate and eventually kill the very thing that they were made to support. Another point, every child you have must compete with every other child you have as well as yourself, if none of the parents died the children would rapidly die off as they are weaker then a full grown version of themselves, usually. Then a single plague comes through and kills the whole population as there was no opportunity for genetically unique children to propagate and evolve. The only reason sexual reproduction is even favored is due to the ability to shuffle genes and make unique combinations, an immortal parent would defeat that purpose.
You are right about the goals of life but you are currently lacking in the ground work needed to properly evaluate them.
>>8017186
woah, nice explanation! congratulations, thank you to give me new faith about darwinism.
>>8017210
Death is planned for in any multi cellular organism that isn't straddling the line between colony and true multicellularity. This is because of cancer, it will pop up eventually, you personally have had at least a couple cells become cancerous today and it is due to this mechanism that the cells did not become a tumor but instead induced apoptosis. Death comes in many forms and there is several possible reasons, the most notable being that this accumulated damage being gained is being propagated through the capabilities to give birth to new children as well as the fidelity of those gametes. So think of it less as an immortal creature gets more chances and more as an immortal creature would have progressively more aberrant offspring and increase the chance of death during said birthing process. It is also important to note that during this entire time these "imperfect" parents are consuming resources that more "perfect" children could be consuming reducing overall fitness of their population and family line.
>>8017150
Cnidarians will take over if environmental system which favor their proliferation arise.
See: jellyfish seas as a result of global warming.
>>8017218
Sorry "This is because of cancer" is not entirely accurate by any means, there is many points where cell death is very important. More so there are also times were organism death is also important such as an ant dying for a queen or a mother dying to feed her new born children. I unintentionally ascribed a teleological character to cancers role in life.
>>8017219
~circumstances
>>8017210
DNA doesn't plan anything beyond mRNA. Currently the main theory of the cause of aging is our DNA gets damaged over long timeframes which leads to senescence. It's a complicated process, especially when you throw in other environmental factors. So I recommend to stop thinking of DNA as having a will of its own, in the same sense a cup of water doesn't have a will of its own. A species can remain viable even if they die in ~80 years (or even a day or so if you look at certain bugs)
If you want an interesting read, google/wikipedia calorie restriction
>>8017219
Right, but that's due to an environmental pressure rather than since some cnidarians are biologically immortal
>>8017145
But he's right. You can't have survival of the fittest when all species survive.
>>8017230
I'm proponent of evolution but you are just wrong. There are many things that contribute to the whole survival of the fittest thing. You can't possibly have all species survive as creatures eat creatures because they are an easy source of nutrition. Also there is only X amount of sunlight that hits the earth and only X-a amount of light that is used by life to produce sugar and food. There is never enough food or resources to stop survival of the fittest, even us humans are subject to this.
>species is immortal
>continues to reproduce
>population grows geometrically
>wastes all resources in its natural environment
>without food, it dies off
>>8017228
Not necessarily, current conditions prevent them proliferating out of step with predation.
Environmental stress keeps their numbers in check. When conditions no longer do, however, they'll go off the rails in spite of predation.
>>8017234
There are any many mechanisms. The "popsci bullshit" he refers to is when someone says there is only this specific thing that causes death and therefore we need to fix this to become immortal.
Telomers are actually part of this, sometimes, because they allow for rapidly, and inappropriately, reproducing cells to essentially age themselves out. It was calculated that if we avoided disease and accident our entire life span humans can theoretically live to upwards of several hundred years. We only use telemorase to restore the caps in germ line cells and the like because frankly after the age of 60ish we are useless as a vector to pass genetic information and in the case of men subpar genetic material is passed. There is no reason to restore this end capping as it won't magically restore the health of the cells they are in.
Telomers are a cap on the end of DNA because we don't have circular DNA so when it is being transcribed and the polymerase reaches the end it cannot replicate the last little bit and snips it off. It also prevents our chromosomes from fusing which would be really really bad. Telomeres are a way to measure the age of a cell but by no means are anywhere close to the end all catch all for age related deaths.
Perhaps this will make it easier, imagine you get one noticeable mutation once every 10k replications. There are about 15 trillion cells in an adult body and they completely replenish. That means, pretending that you got no mutations from birth to your 18th birthday, you get 1500000000 mutations every seven years. Now imagine if that happened to your brain cells, your heart, your stomach, your kidneys, your pancreas, or even your skin. So instead of fighting this losing battle your selfish genes just take what they can get and bail before shit gets too weird.
>>8017240
Ever done any ecology? When a prey species explodes within a year or two the predator species explode as well and out pace the prey until they kill off too much prey and the rapid decline begins. You don't know nearly enough about cnidarians anyways to imply that they will explode soon, despite the fact they have existed for millions of years through mass extinctions that would be perfect for them to take over in the wake of.
>>8017253
you just explained it perfectly well, it conveinced me. thanks
>>8017262
Glad I could help.
>>8017197
skimmed through this thread and was happy to see your comment, OP.
>>8017256
Have you? Almost all jellyfish predators are other jellyfish species. Not only this, but the non-jellyfish predators will suffer badly in ocean conditions which increasingly favor jellyfish proliferation.
They will explode if environmental conditions which favor them disproportionately arise. You cite the past as though we have record of their numbers over past millennia. They may well have bloomed in the past, as they may in the future, there numbers can always decline or equalize again given another change in ecosystem conditions.
>>8017186
This is interesting, the bit about competition within the same species. I learned with frogs and their lifecycle the adults and the tadpoles require different foods to survive, ensuring no competition between the old and young ( the old clearly have the advantage.)
If organisms in a species never died, how would they adapt to a changing environment? There needs to be a death and reproduction cycle so that mutations can occur and the population can change over time.
