Death, why?

[Sayonara]

That my friend is a question best answered by Charles Darwin.

No it isn't. He didn't know genes existed - nobody did then.

 

 

it hasn't evolved because there is no niche to be exploited by evolving it.

you know' date=' grow wings for the air, grow lungs for the land...grow immortality for...????[/quote']

Do you know what niches actually are, and how selection works?

[JHAQ]

Death is the price we pay for being able to reproduce sexually . Only clones are immortal in a genetic sense . We are a genomesd way of making another genome & the genome has no 'interest ' in our longevity except that we survive long enough to transmit it .

[aguy2]

There has been a lot of excellent replies to this thread and I have been too busy to respond to them in a timely manner.

 

Coquina's post #22: I believe Muslim's do this.

 

Reverse's post #25: Neural cells are not normally replaced.

 

Sorcerer's post #30: I believe the 'relatively immortal' organisms would have an advantage as 'K' was reached. As the 'old cowboys' say, "Old age and cunning beats youth and skill every time." Experience and its associated 'wisdom' is a big advantage.

 

Mokele's post #32: The 'environmental insults' you speak of are a good point. Mabe we should talk in terms of 'relative immortality' vs. 'absolute internally programed mortality'?

 

I think they main point for this topic is that death hasn't evolved, imortality needs to evolve for things to be immortal, life can only work with what it has to evolve, and the chances of an immortal individual occuring is low, like any adaption I guess, but I doubt it would have happened, even if it has, my argument give reason as to why it wouldnt be advantageous.

 

I think the point here is more that 'relative immortality' should have been the 'norm', and it is 'absolute internally programed mortality' that had to evolve.

 

aguy2

[reverse]

No it isn't. He didn't know genes existed - nobody did then.

 

 

Do you know what niches actually are' date=' and how selection works?[/quote']

 

Yea right, I'm either very dumb or very smart.

depends on how clever you think you are.

 

just because I gave two physical examples, doesn’t mean that I think a niche has to be an actual environment.

and doesn’t mean it just applies to evolution, I like looking for marketing niches as well.

 

why would you dump all the complexities of a situation onto a person with a basic question?

 

 

edit

sorry shouldn’t have gotten grumpy.

just realised.

see, even two thoughts (yours and mine) struggle for a place to exist

[Glider]

Death is the price we pay for being able to reproduce sexually .

Ah, well worth it then.

[ed84c]

question.

 

are any of the cells that were alive in a person at two months old' date=' still there at sixty years.

or have they all been replaced?[/quote']

 

Brain Cells, Nerve Cells

[Sayonara]

As the 'old cowboys' say, "Old age and cunning beats youth and skill every time." Experience and its associated 'wisdom' is a big advantage.

Only if you happen to be in a higher genus.

 

 

 

Yea right' date=' I'm either very dumb or very smart.

depends on how clever you think you are.[/quote']

No it doesn't.

 

just because I gave two physical examples to a person who asked a very basic question, doesn’t mean that I think a niche has to be an actual environment.

Nobody said you did. In fact by asking you if you know what they are, I am deliberately avoiding saying that you think a niche is X. Do you see how that works?

 

and doesn’t mean it just applies to evolution, I like looking for marketing niches as well.

Ecological niches don't work in the same way as marketing niches, so try and avoid thinking about them in those terms.

 

sorry shouldn’t have gotten grumpy.

I only asked a simple question

[reverse]

 

 

I only asked a simple question

 

ah, a politician.

 

you think like my brother!

 

those blasted greeks, putting everything into boxes for logical contemplation.

 

how about this.

 

Energy comes from the sun.

it hits earth and is then re radiated.

life occurs in that small delay between absorption and re emission.

now start to construct your web of evolutionary events from that point.

all reasons can stem from that.

[Sayonara]

Where does chemotrophism fit into that model?

[aguy2]

Death is the price we pay for being able to reproduce sexually . Only clones are immortal in a genetic sense . We are a genomesd way of making another genome & the genome has no 'interest ' in our longevity except that we survive long enough to transmit it .

 

I think we seem to be reaching a consensus that there seems to be some sort of linkage between 'absolute mortality' and sexual reproduction. They both arose at about the same time in the same species, and the genetic mechanisms that insure 'absolute mortality' definitely don't 'kick in' until after the the organism has had a chance to bear and rear it's young.

 

aguy2

[reverse]

Where does chemotrophism fit into that model?

 

good point!

 

we seem to be wandering off the topic here.

 

will see if I can start another topic about how nature chases energy.

 

like the present focus around sex and death.

 

has all the makings of a great thriller.

 

lets see if we can find some examples from nature to support or erode the sex death link.

[Mokele]

Quote:

Originally Posted by aguy2

As the 'old cowboys' say, "Old age and cunning beats youth and skill every time." Experience and its associated 'wisdom' is a big advantage.

 

Only if you happen to be in a higher genus.

 

While that's true for experience, many "lower" animals can benefit from age.

 

For instance, many of the larger reptiles have disproportionately long lifespans (50 years max for some pythons, 30 for large monitors, over 100 for crocodiles), and chelonians, well, there's even questions about whether or not they do ever die of old age, versus just accumulated environmental insults.

 

The benefit is indirect: Reptiles never stop growing, though the growth rate slows considerably after maturity. Thus, while a Saltwater croc is sexually mature at 10 feet, an 80 year old male can be as much as 18 feet long. This massive size increase brings advantages to both sexes. In territorial species (where the male is larger), the old, big males can defend more territory and mate with more females.

 

For females, though, advanced age, and it's consequent massively increased size, brings another advantage, of the sort most favored by evolution: more offspring. A just-mature, 10 foot female burmese python might lay a clutch of 20-30 eggs, while a 20 year old, 17 foot female can lay a clutch of over 100 eggs. Extremely large females can even double-clutch, effectively doubling their already huge per-annum reproduction.

 

So age can have more benefits than just experience.

 

Mokele

[reverse]

While that's true for experience' date=' many "lower" animals can benefit from age.

 

the old, big males can defend more territory and mate with more females.

 

Extremely large females can even double-clutch, effectively doubling their already huge per-annum reproduction.

 

So age can have more benefits than just experience.

 

Mokele[/quote']

 

yes size, it takes time to fatten up.

 

I'm thinking , someone once told me that evolution happens in spurts, not in a gradual even pace.

 

Suggests that sudden rapid external forces come in to play.

 

so maybe your fat old crock is no better prepared than a small crock to survive a primary culling event, something like a drought say.

[Sayonara]

While that's true for experience, many "lower" animals can benefit from age.

I agree, but by higher genus I meant 'things that can learn' (in a general "it's got a brain" sense).

 

I.e. not beetles, moths, nematodes, sea cucumbers... and so on.

[aguy2]

In doing some web research on possible linkage between sexual reproduction and 'programed mortality' I've run into a neat site called "Palaeos: The Trace of Life on Earth". http://www.palaeos.com/Default.htm#MainMenu On one of its pages called "The Diversity of Life" I couldn't help but notice the following statement: "Finally, its important to remember that this site, like life, was not planned. It grew and evolved. It began and, one day, we will become bored and it will die. It may be useful, but it has no overriding mission other than the fun of creating it."

 

Even considering that we are investigating 'uncharted territory' this may be quite a 'stretch', but could it be possible that after the excitement and stimulation of surviving to relative maturity and the thrill of sexual reproduction the organism loses interest in life? After all, "Jack and Diane" are right, in that, "Life goes on, long after the thrill is gone."

 

aguy2

[Sorcerer]

Ok, Ive been thinking about mokeles point as to why would immortal organisms suffer from long term consquences when mortal ones don't. This is what I've come up with so far:

 

Let's assume we have 1 mortal and 1 immortal organism. They both produce 2 offspring but asexual means and the mortal organism is dead before its grandchildren are born.

 

Now we can see that the immortals population swamps the mortals rapidly, with 2+1^2 at the second generation, this leads to K being reached far sooner. Now the mortal organism has MORE generations before it reaches K, this allows more chances of mutation and adaption to other niches, while the immortal organism is effectively still producing 2nd generation offspring at K, these will probably differ the least and hence have the worst chance of adaption.

 

So, the long term consequence of being immortal is a lower ability to adapt, when K is reached, not being able to adapt to new niches is a disadvantage, thus the immortal organism is at a long term disadvantage when compared to the mortal one.

[Sayonara]

Surely that's only a valid comparison of adaptive success if K is the same for both species?

[Sorcerer]

Ok, say the immortal is a mutant of the original mortal, so they occupy similar niches but keep them in different ecosystems to keep competition out of the equation.

 

Also, I just thought perhaps it would level out since selective pressure would be far higher earlier for the immortal, so adaption rates could be balanced.

[Sayonara]

Here is a graph comparing two populations, where the only difference between the two species is that one is mortal, the other not.

 

Assumptions:

 

Two offspring per breeding pair per generation.

 

Parent generation of mortal species dies when grandchildren born (i.e. mortals only have two sets of offspring.)

 

 

Formulae:

 

Mortal - Population = Parents*2 - grandparents

 

(The population rise on generation n+1 is the population of generation n, plus that number again (divide by two for breeding pairs, multiply by two for two offspring per pair), minus the population of generation n-1 (grandparents mate then die).)

 

Immortal - Population = parents*2

 

(Immortals produce two offspring per breeding pair per generation, for their entire lives.)

 

 

 

No matter where you set the K boundary, the immortals hit it first.

 

Interpretations?

[Sorcerer]

Hmmm I was gonna do that but my maths sux and can never be bothered cracking out. So basically its an exponential series vs a geometric series....... now lets' set a limit for K and make an assumption that the pop/n crashes to 75% K and see what thats looks like..... by lets' I mean you sayo I cant be naffed.

[reverse]

After all' date=' "Jack and Diane" are right, in that, "Life goes on, long after the thrill is gone."

 

aguy2[/quote']

 

Maybe, but then again, how old was Abe Lincoln when he started to get his life on track.

[aguy2]

Maybe, but then again, how old was Abe Lincoln when he started to get his life on track.

 

I don't have to look that far for an exception. I went back to school at age 59 and got my degree. I completed 56 semester hours in 12 months with a 3.4 gpa, and it was as much fun as it was hard work.

 

aguy2

[reverse]

Boredom.

 

Life just looses interest.

 

This whole subject of conquering death has the most unusual connotations if you stop to think about it.

Would we retire how would we remember all the names of the thousands of family members we would build up. How long would a judge sentence a prisoner to life in prison for?

And the one you have cleverly pointed out, would life loose its novelty value?

 

On this last one you could write a book..

 

But mostly I think your initial idea stems from the youth culture and modern schooling system.

Children are all sent to one big building where they develop their own pecking order and value systems.

Think, if there wasn’t that scholastic break from the normal activities of the real world, and you had all the time in the world (because you were immortal) you could learn everything by actually being there, rather than by reading it from books in a classroom)

 

To learn geometry you would fly to India and draw out a drainage system for a small village that had severe sanitation problems.

 

With enough time, even very untalented people can learn skills they are not naturally gifted in.

For example, that robot you have as your personal icon, say you couldn’t turn a bolt to save yourself.

With time, you could build that by hand, and when you were finished you could keep improving upon the design as you learned new skills.

Would life get bored?

I don’t think so. The possibilities would open up dramatically.

[ed84c]

I meant though its a choice isnt it; if you get bored, kill yourself, if not then carry on living.

 

Things (even Heaven) that last for ever, scare me, as such i think a life time of 1000 years, would be nice.

[reverse]

Ok' date=' Ive been thinking about mokeles point as to why would immortal organisms suffer from long term consquences when mortal ones don't. This is what I've come up with so far:

 

So, the long term consequence of being immortal is a lower ability to adapt, when K is reached, not being able to adapt to new niches is a disadvantage, thus the immortal organism is at a long term disadvantage when compared to the mortal one.[/quote']

 

Hey I like it.

you know what we are going to find in the end?

that there is a bit of luck involved in all this.

and external events such as solar flares and meteorite impacts occurring at random times have the same effect upon the shape of the tree of evolutionary life ,as a Japanese business man has on a bonsai plant.

 

if an immortal species does prosper or not may be just down to good timing, like that Gwenith Paltro film ":sliding doors"