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    • #657
      James
      Participant

      Could it be possible that death has evolved? The very first organisms, however they came about, may not have had death; however as time progressed, populations that were immortal grew so large that competition was extreme, and eventually led to these organisms not having the environment to be able to reproduce. As this was happening, another population, which had earlier had a mutation to limit their lifespan was progressing well, with competition never enough to halt the organisms not being able to reproduce. Thus, the population that had limited life span actually had a favourable position and then went on to evolve, spread and go on, whilst the population of immortal organisms could not evolve, and eventually died out by extraneous variables. Could it be possible the first organisms were immortal, and that death is evolutionary beneficial?

    • #21097
      biostudent84
      Participant

      At the moment, I disagree…but if you can defend it against debate, I could probably be convinced.

      I’ve stated them before, but I’ll say it here as well to set the record.

      The two biological laws: Why we live.
      1. Survive to an age where you can reproduce
      2. Reproduce successfully*

      *reproducing successfully stipulates that at least one of an organism’s offspring also fufills the two laws. R-selected organisms like flies do this by having thousands of offspring. K-selected organisms like humans do this by living a long time, helping to raise our children and our children’s children.

      Hmm. Two statements and a disclaimer and I’m already wavering. Anyone else have any thoughts?

    • #21141
      2810712
      Participant

      Good q.
      Bacts have death, viruses do , fungi probably don’t have it. So, there is no uniformity .
      I think, it really didn’t occur the way u have stated.
      One more IMP point
      See the early organisms were just envolope of biomolecules with meatabolism occuring inside. So, they reproduced by deviding , so they had death.

      hrushikesh

    • #21170
      mith
      Participant

      Do you mean ageing death or death in general? Because bacteria don’t need to evolve the ability to die, a few cups of molten lava would kill them.

      I don’t think your theory holds(assuming you’re talking about death through ageing)….

      Let’s assume that indeed the first organisms were immortal. They would reproduce and evolve through successive generations. When the population reaches carrying capacity, the ones that were not as adapted would die out, not from age but from starvation or possibly be eaten.

    • #21196
      James
      Participant

      Yeh, I guess immortal orgainisms would be unlikely to die out unless there was another particular disadvantage that came along with being immortal. The whole idea seems a bit silly,as from a genes view, with immortality there would be no need to reproduce, as the genes carried by an organism wouldn’t need to be passed onto a new generation as they would be around forever anyway. O well ๐Ÿ˜

    • #21218
      2810712
      Participant

      Yeah, death due to ageing has evolved, probably.
      But , how can we say that early lifeforms were immortal ???

      hrushikesh

    • #21234
      mith
      Participant

      Immortality would mean it is immune to ageing.

      1st you have to understand the nature of ageing…is this something the cell wants? Or is it an inevitable decline in the condition of its genetic material(incomplete copying, random mutations etc)?

    • #21251
      2810712
      Participant

      How can we call immortality means ageing-immunity ? ? ?
      I’ve understood , probably, ur concept , it seems to be correct, and thus ageing did evolve but we can’t say that death evolved , it was just an imporatant result of that .

      hrushikesh

    • #21320
      mith
      Participant

      Well not ageing is included in the defintion of immortality which probably would include invulnerability but I don’t think that was what james meant.

    • #21470
      GreenDog
      Participant

      It looks like a very interesting idea, and it might be possible. Bacteria for example, the simplest organisms, do not die of “old age”, though they do age, have many mechanisms of programmed death. It seems like there is no reason for bacteria co commit suicide when they can live forever, but in fact persistent mutants (defective in PCD mechanisms), die very fast. Persistent populations have many disadvantages to usual bacteria. The ability to die serves an important role in the bacterial population.

    • #21474
      biostudent84
      Participant

      One of the smartest professors I ever had (Dr. Charles Blem) once taught that while not all organisms have it in their genes for programmed death, most do. Humans have their own programming to die…it’s called cancer.

      “No matter how healthy you keep your body, if you live long enough, you will get cancer.”

      Kyle

    • #21478
      mith
      Participant

      Isn’t a cancer cell an immortal cell?

    • #21484
      Poison
      Participant

      cancer cells are immortal but they do harm to their hosts. (I could’t find another word instead of host). I mean, when you have cancer, (a malign one) sooner or later it will do harm to your body and lead the body to death.

      I agree with Kyle,
      It doesn’t matter how healthy you live (like not smoking or such kind of things) one day ,(usually after a certain age) you will have cancer…

    • #21491
      James
      Participant

      So cancer is our way to limit life, which relies on DNA mutations. Perhaps at one stage DNA did not mutate,however it evolved to do so, thus leading to a limit on life.

      quote :

      not all organisms have it in their genes for programmed death, most do.

      So what organisms do not have programmed death?

    • #21495
      biostudent84
      Participant
      quote James:

      So cancer is our way to limit life, which relies on DNA mutations. Perhaps at one stage DNA did not mutate,however it evolved to do so, thus leading to a limit on life.

      quote :

      not all organisms have it in their genes for programmed death, most do.

      So what organisms do not have programmed death?

      Cancer is ONE way we limit life. Let me get in contact with Dr. Blem and I’ll ask him for an example. One is a bird….but can’t remember which one.

    • #21503
      mith
      Participant

      an immortal bird?!

    • #21506
      2810712
      Participant

      How can cancer cells be immortal if they get divided, division = death here, as in bacts???

      And see if cancer is one of the ways of getting deaqd after some years we would be able to stop all types of cancer and thus get nearer to immortality.

      hrushikesh

    • #21526
      Poison
      Participant
      quote 2810712:

      How can cancer cells be immortal if they get divided, division = death here, as in bacts???

      And see if cancer is one of the ways of getting deaqd after some years we would be able to stop all types of cancer and thus get nearer to immortality.

      hrushikesh

      hey, I think you should get some info about cancer.

      If we stop all types of cancer (and I don’t think this is likely to happen), maybe we can live longer.

    • #21555
      2810712
      Participant

      yeah, its less likely to happen and i’ve also written that we get NEARER to immortality .[ i’ve not written than we get immortal ]
      ๐Ÿ˜ฎ I don’t have complete knowledge about cancer , but one think i doubt here is saying that cancer cells are immortal, please if anyone could help me …

      hrushikesh

    • #21558
      mith
      Participant

      Actually poison, i’ve switched my essay topic to cover cancer somewhat, specifically I’m discussing how internal cancer risks(colon in my case) would differ from external cancer(skin) as age progresses. Any info you could pm me with would be greatly appreciated :D.

    • #21577
      Poison
      Participant
      quote 2810712:

      I don’t have complete knowledge about cancer , but one think i doubt here is saying that cancer cells are immortal, please if anyone could help me…

      yes. cancer cells are immortal, unless you kill them or unless the cancer cells kill their host. the cells are immortal but as they spread (metastasis) they harm the body. Because cancer cells are not identical to normal cells. they are different. and note that it is an uncontrolled division. the cells divide continuously. normal cells divide to a point and then stop. the mechanism that stops them is called contact inhibition.
      cancer cells kill their hosts. (or you can call it the body.) when cancer spreads to some organs it causes many activities to stop and finally the person dies. When the person (or it might be more logical to call organism instead of person) dies all metabolic activities stop as well.
      so doesn’t that mean the death of cancer cells too?

      @mithrilhack
      I will try to find some info. but if you give me more details about what the subject exactly is, it will be easier. Feel free to pm me.

    • #21580
      biostudent84
      Participant
      quote Poison:

      so doesn’t that mean the death of cancer cells too?

      Cancer cells only stop dividing after the death of the patient. This is due to the lack of incoming sustenance; proteins, carbohydrates, and especially lipids. Cells need these to divide. Without them, cells will die.

    • #21585
      Poison
      Participant

      Thats right Kyle. that is what i was trying to say. ๐Ÿ™‚ when the patient dies, the cells die too. but if make a culture of cancer cells , they won’t die as long as you provide optimum conditions.

    • #21591
      biostudent84
      Participant
      quote Poison:

      Thats right Kyle.

      Wohoo! I know something after all! lol

      So is death a biological response to kill the cancer cells?

    • #21597
      2810712
      Participant

      See cancer cell and cancer tissue are diff. So a cancer cell divides and i consider this as its death. Am I right ? ? ? But cancer tissue doesn’t die [ in natural conditions mostly]untill its host dies same as parasites in our gut , would you call them immortal ? ? ? Ofcource not. So both cancer tissue and cancer cells are mortal. Here immortal = never dying This eqn says that viruses are also not immoartal [ if they are living.]
      If this eqn is applicable then this whole proof is right.
      Is it ? ? ?

      Please correct me. I have not read this in any book but i’ve also not read that cancer cells are immortal. So, i need some proof.

      hrushikesh

    • #21601
      biostudent84
      Participant

      When a cell divides, it forms daughter cells.

      In essence, the parent cell exists as two cells now. Think of those old (innaccurate) sci-fi movies about cloning. The original organism’s identity is split along with its body. It doesn’t die, as there is no dead cells.

      Immortal, when used in biology means “Capable of indefinite growth or division.” I think you are confusing the term “invulnerable” to the term “immortal.” The term Immortal here means that it will live forever provided it gets everything it needs and some outside force does not kill it.

    • #21610
      Poison
      Participant
      quote biostudent84:

      So is death a biological response to kill the cancer cells?

      hmm… I haven’t thought about it that way. I think it is just the result. not a response.

    • #21614
      biostudent84
      Participant
      quote Poison:

      hmm… I haven’t thought about it that way. I think it is just the result. not a response.

      Probably it is a result. But it is still possible that death is a response. When I go into anaphylaxis (shock from allergies), it is the result of a poison. While the poison is dangerous to my body, the shock is far worse. It cuts off all breathing passages and I have seven minutes to live between the onset of anaphylaxis and death.

      Now, anaphylaxis is not cancer, nor remotely close, it still is an idea.

      Kyle

    • #21638
      Poison
      Participant

      sounds logical. but still i’m not sure… I will think about it a bit more… ๐Ÿ™„

    • #21655
      mith
      Participant

      I was just looking over some of our old threads and I came across one on telomerase(Originally posted by James).
      http://users.rcn.com/jkimball.ma.ultran … meres.html
      According to this website paramecium and germline cells are immortal.

    • #21659
      2810712
      Participant

      I don’t mean invulnerable. I’m considering the division of a cell as its death.
      See this-
      this will catch u in words
      There are 3 cancercells which dived in two each .
      So, how many individuals are there.
      3 0r 6. That, way a cancer-tissue is a single individual. That i cannot agree . Please please please help me out…

      hrushikesh

    • #21720
      Poison
      Participant
      quote 2810712:

      I don’t mean invulnerable. I’m considering the division of a cell as its death.
      See this-
      this will catch u in words
      There are 3 cancercells which dived in two each .
      So, how many individuals are there.
      3 0r 6. That, way a cancer-tissue is a single individual. That i cannot agree . Please please please help me out…

      hrushikesh

      couldn’t understand your question… ๐Ÿ™„

    • #21763
      2810712
      Participant

      How can cancercells be immortal ?

      In Oxford dictionary-
      immortal= living forever
      invulnerable=impossible to harm or damage.

      I could not find the biological meaning of these two , if it is different, in any biological dictionary available to me.

      How can we say that if a cancer-cell divides then it doesn’t die???How can we say that the identity of parent cell is maintained in the daughers.And if one of these 2 daughters die then what would we say ? the parent is half-died???

      See if there are 3 cancercell in a culture, then the no. of individuals=3,
      if each of them mitots then 6 cell are formed , so how many individuals are there ? + 6 or 3 ? I’ll say 6 so, although they have same genes we shouldn’t say that they are same individuals.

      So , cancer cells are not invulnerable, but they are also not immortal as they are not living forever. SEE the example of paracite-colony that dies whith their host same as cancer TISSUE. But individual paracites may die , but colony is still alive. Same is the case of cancercells , individaul cells divide [ =die] and tissue dies with the host mostly.

      pleaseplease please correct whereever possible.

      thank u v much,

      hrushikesh

    • #21784
      Poison
      Participant

      think of bacteria that reproduces by mitosis. when 2 daughter cells formed, does the parent considered to be dead? I don’t think so. the genetic material still exists.
      when normal cells get old then they go through apoptosis. But cancer cells don’t.

    • #21833
      2810712
      Participant

      My mind is tending to say cancer cells dying abnormally. Why call them alive wwe have posted long definitions of life and if the divided cells r the parent cell itself then there is no reproduction, this is a contradiction.
      See a man can dy of cancer, hepatitis even in young age [ i.e. without ageing (ageing is similar to apoptosis)] So, don’t we call them dead ? We do call them dead. So , the way something dies doesn’t affect the conclusion that it is dead.

      Please please please correct wherever possible.

      hrushikesh
      _______________________
      natural” doesn’t mean not harmful. It is safer in most cases as it is time tested in most cases as people in centuries before didn’t have artificial cosmetics.

      hrushikesh

    • #21836
      Poison
      Participant

      I’m really sorry but I couldn’t understand your point of view. ๐Ÿ˜ณ Mitosis is a way of reproduction, as you know, asexual reproduction.
      cancer cells do not go through apoptosis. I think apoptosis is similar to death not aging.

    • #21866
      2810712
      Participant

      Thanks, poison you are really trying to help me, you give me the feeling that there is somebody to help me, thanks.
      My problem: If the parent doesn’t die due to mitosis, then we cannot call the two daughters cells as new organisms, means there has no reproduction occured. And if we call them a new organism , then we cannot say that the parent is still alive.

      Also, what ever thway of death be, the cancer cell dies, so it is mortal -this is what my mind argues.
      Hope i’m able to convey my problem this time. ๐Ÿ˜ณ

      Please help…

      hrushikesh

    • #21877
      canalon
      Participant
      quote 2810712:

      Thanks, poison you are really trying to help me, you give me the feeling that there is somebody to help me, thanks.
      My problem: If the parent doesn’t die due to mitosis, then we cannot call the two daughters cells as new organisms, means there has no reproduction occured. And if we call them a new organism , then we cannot say that the parent is still alive.

      Also, what ever thway of death be, the cancer cell dies, so it is mortal -this is what my mind argues.
      Hope i’m able to convey my problem this time. ๐Ÿ˜ณ

      Please help…
      hrushikesh

      OK, if I understand clearly your problem is that after mitosis it seems impossible to say who is the parent, who is the daughter. Indeed the 2 cells are the daughter cells, and there is no parent cell left, but it doesn’t die since it is just mixed in its offspring. So death or not?

      An interesting thing is this article about aging in bacteria: [url]http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0030058[/ur]l

      But the major point is that you have to make a diffrence between cellular death and death of an organism. I mean an organism as a whole can be considered dead, when its cells are still working (hairs and nails still grows after death).

      HTH

      patrick

    • #21901
      mith
      Participant

      I thought it was a myth that started because the skin shrinks and reveals more hair/nails.

    • #21914
      2810712
      Participant

      Thanks for the link,
      but cell death and organism death are same in the case of a cancer cell as i’m considering it as an organism [ because if we want to call cancer cell as immortal then we need to consider it as an organism.]
      Hope u r getting me.

      thanks,

      hrushikesh

    • #21923
      Poison
      Participant

      2810712, the term ‘immortal’s not our discovery about cancer cells. All the world call them ‘immortal’. ๐Ÿ™‚

    • #22224
      2810712
      Participant

      first of all ,
      sorry for late response.

      I’m also aware that u r not the person who has coined that term, i was just trying to understand the logic [?] behind it, at last i will call it a misnomer, and many misnomers are there in science , so i’ve no problem accepting it as a misnomer.

      Thanks,

      hrushikesh

    • #23876
      Mister Jon
      Participant

      Death is a metaphorical character who wears black robes and wields a scythe, he evolved from a human as his parents had a rare: lack of skin and muscle gene.

      No but seriously i disagree in saying that death evolved, i think it has existed all the time.

      In some relation what i don’t understand is that bible characters lived to old ages of 200/300 even with the lack of medical sciences as we have today. Maybe lives shorten evolvely – but agfain maybe not because now it is believed that people born today are likely tol live to 100

    • #23889
      mith
      Participant

      Well if you go according to the bible, people lived to 1000…but since this is a biology forum, we will not discuss that(see links in my sig).

      Statistics of age distribution show the death rate increasing until around age 100 which then levels off. This means you have almost the same chance of reaching age 120 if you’ve already reached 100.

      Also note that people in the middle ages died significantly earlier than we did usually due to diseases. Even without diseases, they might still have a hard time living long lives because they do not have proper education regarding nutrition…i.e. you’ll still get heart attacks if you eat organic farm fresh hormone free butter.

    • #24338
      ctmdvf
      Participant

      I think in the contrary. Organisms evolved to live longer

    • #24386
      mith
      Participant

      Animals are not selected for longevity but for reproductive success. While having offspring later in life is a factor, the main factor is survival, and courtship ability.

    • #25547
      Tamsicle
      Participant

      Doesn’t evolution mean death anyway? There has to be some sort of mechanism for passing useful information on to offspring….

    • #25588
      James
      Participant

      I was thinking there could have been a situation where reproduction was hindered due to the inability for organisms to die, thus death was favourable.

    • #25592
      Poison
      Participant

      If you have children that means your genetic material goes on existing. (semi-consevatively) So, your genetic material is living. Maybe this can be considered as living of an organism forever. I don’t know how it came to my mind. Just a thought… ๐Ÿ™‚

    • #25649
      Tamsicle
      Participant

      Okay so fluctuations in the abiotic environment would pose a challenge to all organisms. As long as this occurs, death is necessary to ensure the survival of all species…right? You know this really one of those fantastic topics that gets you all excited and then you start thinking about it and have what you think is this spontaneous moment of genius…and then you realise it’s completely irrelevent.

    • #25661
      James
      Participant

      I don’t know if you’ve missed the point, but I feel the discussion was interesting.

    • #28356
      ananth
      Participant

      Hi there,
      Death due to senescense is a natural phenomenon , In multicellular organisms u see it as a physical process and in prokaryotes we dont as the parental cell is lost during the fission. and if i am not wrong prokaryotes do undergo conjugation for making sure genes in populations are not lost due to senescense.
      also in multicellular organsims u can treat individual cell is immortal as the also undergo same process as bacteria ๐Ÿ˜‰
      As the site admisintrator said ” Reprodction and sucessfull passing of genes over generations is one of the prime essesnce of life.” once this is fullfilled the organism is practically dead.
      Ananth

    • #30273
      doe
      Participant

      DEATH IS THE END OF YOUR PHYSICAL STRUCTURE’S PROCESSES THAT ALLOW IT TO FUNCTION CONTINUALLY. I AM A PANTHEIST/STRING THEORIST AND I BELIEVE THAT ONE’S LIFE’S SOURCE OF ABILITY,(PHYSICAL/MENTAL) WHICH INCLUDES ALL OF THE SENSES AND PERCEPTIONS OF THE WORLD, IS KEPT IN YOUR BODY LIKE A STORAGE COMPARTMENT, ONLY TO BE RELEASED BACK INTO THE UNIVERSAL-WIDE CULMINATION OF ALL LIFE’S ENERGY. THAT’S OUR DEATH. THUS, THE TRADITIONAL IDEA OF DEATH CHANGES, MAKING ITSELF SIMPLY A TRANSITION FROM OUR UNDERSTOOD PHYSICAL PERCEPTION OF THE WORLD INTO AN ENTIRELY NEW PERCEPTION OF THE UNIVERSE THAT IS UNCOMPREHENDABLE TO THOSE THAT HAVE NOT EXPERIENCED IT. ASK SOMEONE THAT HAS HAD OUT OF BODY EXPERIENCES, EXPERIENCED NIRVANA OR ANYTHING OF THE LIKE.

    • #30336
      canalon
      Participant
      quote doe:

      DEATH IS THE END OF YOUR PHYSICAL STRUCTURE’S [bla bla].

      First you do not need to shout, release you Caps locks key please. Second, this answer is completely out of topic. We are discussing the evolution of death, not its meaning. Thanks

      Patrick

    • #33598
      freindhacka
      Participant

      It would seem my post here would be a year or so to late.

      Lets take this into account. Possibly the only rule any organism with genetic material has to obey.

      #1. Replication…..

      Nothing else matters to a piece of genetic code besides that. Now lets assume that the life-giving soup that first started life, started it with the simplest Genetic combination. One amino acid combined with another to form a chain. This chain doesn’t really do much. After a while a combination is found that can possibly replicate itself. This gene, naturally will be “Immortal,” because it has no devices for mortality as of yet. Except for outside forcies IE lava lightning etc. So this thing keeps on replicating. Perhaps it starts combining with itself to become an even longer chain. There are only soo many base pairs in DNA so there aren’t a whole lot of possible combinations. The combinations “Genius” comes in with the length of the base pairs. DNA is Double-Helix, allowing for some protien codes to overlap and space for hormonal triggering.

      I’m not a geneticist, but I believe that lacking a membrane and other Organelles to repair, a really simple genetic strand is quote “Immortal.” It cannot die on it’s own means. Only when the genetic strand becomes complex and evolves a way to self-repair and maintain does self death start to show itself.

      Mutations will often kill an organism or render genes incapable of “Replicating.” Thus effectively killing the organism. Cancer is the more common form to us humans, though cancer is the multicellular form of mutation.

      Ok now back to immortality. Immortality is inherent in all living things, Ie replication. Self-repair and maintainence is what dies out. Certain genetic triggers/hormones slow becuase of what is known as the Hayflick limit. Something that shows up in a DNA strand like AAAAAAAAA followed by a stop code is kind of like a spacer. This spacer shows the absolute end of a certain protein chain or trait however, this strand is shortenend everytime the cell copies itself. If the original does not die or sustain massive damage it will remain with the original number. IE certain cells that compare to stem cells and can be found througout the body all throughout an organisms life.

      Most cells in the body have specific jobs. Blood cells, liver cells, etc. Some of them have genes triggered in them to tell them what kind of cell they are to be and what they are to do. Blood cells, multinucli, brain cells etc. The thing is, just about all the cells in any organism contain the genetic material capable to create the exact organism again. The problem lies in the same feat that cloning researchers are trying to get around. How do we trigger the genes in a blood or muscle cell to work within a blank stem cell, and how do we trigger the newly created cell to produce a new organism instead of just making a blood/muscle/brain cell. People age because once they pass their peak age, the hayflcik limit triggers the cells to start ignoring more and more subsequent damage. The hayflick limit can however, be ignored if the correct trigger is found. Unfortunately I believe this would be like overhauling a battleship. All new guts/cells.

      Triggering peak age restoration would have to be gradual, instead of taking a hormonal supplement that would cause all the cells in your body to start killing/replacing/rebuiliding etc. This would probably have the same effects of cancer. I think two teachers we could learn from would be reptiles and single celled fungi. As most of us know, reptiles posses unprescedented regenerative capability. If we could find out what triggers this we might be able to slow, stop, nay reverse aging. However reptiles are cold blodded and their slow metabolisms work well with regeneration. Instead of a Chain reaction as we would see in a warm blodded mammal, a lizards slow acting metabolism allows for a slower non-degenerative regeneration, instead of a speedy cancer. The reason for cell aging is partly due to the hayflick repeats, but it is also in part due to the fact that once a cell is told to do something, it wants to be lazy and just do what it was told. Once that blood cell becomes a blood cell, it’s hard for him to turn into other cells unless correctly triggered. Again if he’s something else, he can’t revert back to a stem cell and regenerate his youth. We can replace him however, from already existing stem cells with the appropriate starting hayflick repeats.

      In short, I believe that aging by death is due to evolution and complexity. Ie magnets swirling around will start sticking together versus if you’re vehicles serpentine belt snaps. The vehicle won’t just fix itself or snap together the way it wants to. It is possible to fix the vehicle if you could send it backwards through the assembly line.

    • #34382
      scoophy
      Participant

      ๐Ÿ˜† I guess I’m late to respond, too…

      I think death (speaking of individual death) is the evolutionary by-product of the development of individuality. As long as an organism has the ability to reproduce by dividing into two daughter organisms in a way that it goes up completely in these daughter organisms and no one can tell who is the mother and who is the daughter (dividing and doubling not only the genome but the entire body so that each daughter gets half of the mother’s body parts) I would indeed call this organism immortal (theoretically – as we know even these organisms can age).

      This is not only true for single cell organisms, even some metazoa such as corals and many plants can reproduce (or be reproduced) by divison: If you part your big asparagus plant into two halves and continue to grow them in two separate pots, would you say it died?

      But as soon as sexual reproduction becomes the only way of reproduction whithin a species we get a population with only individuals and death becomes a biological necessity: Individuals produce gametes that mate with other gametes in order to form new individuals (no one ever being the same), the parent individuals remain the same as they were until age or some external cause sweeps them out of existence.

      Remark: Of course not only genetic diversity causes individuality – the more complex an organism is the greater will be the influence of it’s personal life-history upon its individual development.

    • #34424
      amoebapower
      Participant

      ive heard that turtles are semi immortal, they dont die of old age but of sickness ๐Ÿ˜‰

    • #34440
      mith
      Participant

      I’d say that your source is wrong.

    • #38777
      playboy bunny
      Participant
      quote Poison:

      If you have children that means your genetic material goes on existing. (semi-consevatively) So, your genetic material is living. Maybe this can be considered as living of an organism forever. I don’t know how it came to my mind. Just a thought… ๐Ÿ™‚

      that sounds about the most normal answer on here!

    • #40206
      February Beetle
      Participant
      quote Poison:

      If you have children that means your genetic material goes on existing. (semi-consevatively) So, your genetic material is living. Maybe this can be considered as living of an organism forever. I don’t know how it came to my mind. Just a thought… ๐Ÿ™‚

      I was thinking the same thing in reading all of this, like the cell theory. Each cell comes from a pre existing cell and what biostudent84 said about Mitosis about the parent cell not dying just splitting, well when DNA splits it means there is 1 old strand and 1 copied strand on each doublehelix so the original is always there. Very interesting topic! That’s just my input. So many things going through my head when I read all the posts I can’t orgainze and type it out correctly.

    • #42266
      AstusAleator
      Participant

      my 2 cents. It’s necessary for an organism to eventually die, to make room for it’s progeny. It is also necessary for organisms to die, to drive evolution. An organism with unfit genes, that didn’t die but persisted and kept reproducing, would weaken the gene pool. So…
      Yes. death has evolved, just as methods of reproduction and survival have.

      Someone at the beginning of this thread listed the requirements for successful evolution as:
      1. survive to reproductive age
      2. successfully reproduce
      I would add to this
      3. die.

      Mortality has remained a constant throughout evolutionary time (though changing in frequency and cause). But now, with the development of technology, humans are beginning to challenge mortality, and thus evolution itself.

    • #42640
      AstusAleator
      Participant

      Here’s a thought I stumbled on in the evolution thread:

      For cells to form multicellular organisms or colonies (plasmodial slime mold) there must be intracellular communication. Perhaps with the development of this communication came the differentiation between selfish, altruistic, mutual, and spiteful relationships. At this time, with the development of altruism, cells began being selected for deleterious traits such as programmed death.

    • #42662
      damien james
      Participant

      If only we could uncover secret of pesky telomerase and control chromosome short over time.

    • #47617
      Pepper
      Participant

      It may help to understand death if we try and look at things without being too anthropcentric. We could also consider the genetic material as the true "unit of life".

      The first proto-organisms or self-replicating molecules were probably quite fragile outwith their natural suurondings and at the mercy of the environment. To counteract this they would have developed some form of outer coating – be it a simple carbohydrate or protein coat – to shield themselves. Now, fast-forward a few billion years and we see that this outer protective coating has evolved into something far more complex – the cell. This "super-coat" not only protects the self-replicator, but also repairs it and provides it with everything it could ever want. These "super-coats" eventually form organisms – just an incredibly comlplex way of protecting the self-replicator.

      Viewed in this light there is actually no such thing as death. All that is happening is that the self-replicating molecule (living in a vast super colony) is "shedding" its "coat". It "lives" on in a new body – our offspring are us.

      What has messed things up is that some of these "super-colonies" have evolved self-awareness. In a sense we (mentally) are a but temporary thing existing piggy-back style within the "coat". When the old "coat" ceases to be able to create viable gametes and rear young (new "coats")successfully, it succumbs to the wear and tear of life and breaksdown. The genes live on in the next generation protected in a new body with a new mind.

      This argument doesn’t really explain why death has evolved, but rather suggests that death (from old age) is just an illusion created by our perspective.

      Maybe a bit fanciful though …

    • #47651
      Zeneth Entorion
      Participant

      It is VERY unlikely that death evolved. The longer you live (and are fertile), the more offspring you are capable of generating. Death by old age is most likely a byproduct; in any organism’s natural environment it is extremely unlikely that it will survive long enough to die from old age. Therefore those organisms which survive are those which exchange longevity for a more active life- that is, they use all their energy for surviving other foes and winning mates instead of on repair mechanisms to stop aging. Everything in life is a tradeoff; the organism which uses its energy in the most efficient manner wins.

      As for the "making room for offspring" argument, I’m afraid evolution doesn’t work like that. It isn’t some kind of omniprescient deity which sees the future and then alters the genome accordingly. If and when resources start to diminish due to overpopulation, organisms will simply die off because they have nothing to eat.

    • #47838
      AstusAleator
      Participant
      quote Zeneth Entorion:

      It is VERY unlikely that death evolved. The longer you live (and are fertile), the more offspring you are capable of generating. Death by old age is most likely a byproduct; in any organism’s natural environment it is extremely unlikely that it will survive long enough to die from old age. Therefore those organisms which survive are those which exchange longevity for a more active life- that is, they use all their energy for surviving other foes and winning mates instead of on repair mechanisms to stop aging. Everything in life is a tradeoff; the organism which uses its energy in the most efficient manner wins.

      As for the “making room for offspring” argument, I’m afraid evolution doesn’t work like that. It isn’t some kind of omniprescient deity which sees the future and then alters the genome accordingly. If and when resources start to diminish due to overpopulation, organisms will simply die off because they have nothing to eat.

      Sorry for the huge block quote, but I wanted to have it right there so I could remember what I’m replying tol.
      Zenoth – death and evolution are irreversibly linked. Without death there is no evolution. It is obvious that death affects evolution… so why shouldn’t evolution affect death?

      More to come… my girlfriend needs me ๐Ÿ™‚

    • #47855
      AstusAleator
      Participant

      Take the Damselfly for example. It’s mature morph has no mouth or anus. It is programmed to simply find a mate, copulate, and die. If that’s not an evolutionary trait then I don’t know what is.
      Furthermore, look up apoptosis. Programmed cell death.
      Take Plasmodial slime molds for another example of adaptive death. They are individual single-celled organisms that are capable of functioning as a colony. When plasmodial slime molds form sporangiums, the cells that form the stem "sacrifice" themselves so that the cells that will produce spores can reproduce successfully.
      Altruism is a recognized trait of kin selection. In a nut shell, it is one organism "sacrificing" it’s fitness (ability to succeffully produce viable offspring) for the fitness of one of its kin, so that its kins genome is conserved.
      So, my stance is that evolution DOES determine when and how some organisms will die (if they live long enough).

      Zeneth your statement about the "making room for the next generation" argument is misinformed. You’re right that there is no conscious entity that is making sure that the previous generation dies before they can outcompete the next generation. That doesn’t mean that it doesn’t happen though. In fact, it’s an observable trend in just about every species. There is conflict between generations, but it is brief as previous generations usually die off (or stop reproducing) by the time the new generation reaches its prime maturity. If you don’t understand the evolutionary mechanism behind that I can expound upon it.

      Pepper: I find your comments to be very insightful and fascinating. I like to think of that myself, how "I" am just a consciousness in a body, and that the part that is "me" will only exist in this body. My genes will carry on, but "I" will not. What you said is a good reminder that evolutionary death is not the same as the anthropocentric concept of death that we have developed. Kudos.

      Dave

    • #49417
      Linn
      Participant

      Well I actualy have not answered this Q yet ๐Ÿ™‚

      My answer is yes Death evolved.

      Have a nice day! 8)

    • #49487
      LMJ
      Participant

      This is an interesting topic. My initial thought was that death caused by ageing did not evolve, but was just an inevitability. If something is replicating itself over and over, it is bound to make more mistakes as it gets older, which means that there’s more of a chance a fatal error will occur… But then I thought about the example that James wrote with the initial post, about the comparison between an "immortal" population, and a population with a given life span, but on a more genetic level.

      I guess that if the immortal population keeps reproducing, the copying of the genetic information becomes less efficient over time and mutations build up in the population, making it weaker. The population where the individuals are programmed to die after a certain amount of time would do most of their reproducing in their "prime", so the copying of genetic material would be more accurate. So after the same amount of time has passed, the "immortal" population would be much weaker and not able to compete with the population with a set life span. So maybe dying of old age did evolve?

      Sorry if I’ve repeated most of what’s been said… it’s a really good topic though!

    • #49644
      David George
      Participant

      Did Linn accept that organisms do evolve!!!!!!!!!!!!

    • #49676
      Linn
      Participant
      quote David George:

      Did Linn accept that organisms do evolve!!!!!!!!!!!!

      too funny David ๐Ÿ˜† ๐Ÿ˜†

      I think death is a genetic mutation that happened.

      Now, how can we undo it? ๐Ÿ˜ฅ

    • #49697
      AstusAleator
      Participant

      hehe, Linn’s looking for the immortality gene. Look out world!

    • #49774
      David George
      Participant

      well the immortality gene cannot be recitified according to me because those genes are as such cannot be made to work what I am saying is there is only chances for giving potential immortality for lower species and immortality will make a species vulnerable due to wear and tear.

    • #51577
      mkwaje
      Participant

      This topic really has me thinking. A lot of concepts have been brought forward too. Before we can answer the question of whether death has evolved or not, we have to make sure that the our concept of death are similar. Some say that DNA is the basic unit of life and since DNA continue to exist in our progenies albeit in altered/modified form; then there is really no true death; so we are just really the extension of "life" starting from that primordial soup where life came from. If we see individual cells as the unit of life, then would cell division be some kind of death? If for example, we have a sperm cell and then it combined with an egg cell, can we say that there were 2 individuals that died to bear oone complete organism. Will our fertilized egg cell die over and over again in the process of differentiation to form an embryo? Lastly, we can probably agree that our concept of death is not in the individual cells but in the complete human being, as a baby to an aging human for example. Now if we are to compare death of a bacteria or a slime mold and us, then death would be have to be a different concept for each of them.

      My two cents is this: that all life from the tiniest single celled organism to the most complex multicellular organism (imo, a woman) are in constant battle with entropy. Death is simply the manifestation of that losing battle. But I do not view death as the end of life but a stage in life; so if you say that death has evolved… I would say that death has always been there and would always be there manifesting as cell division, as aging, as cancer cells, as DNA replication errors, as mutations, as absence of nutrients, as accumulation of toxins, etc..

      Another thought, if you will consider our planet as a super organism, having complex interaction of biotic and abiotic factors, involving innumerable distinctly separate individuals all working as a whole for its preservation and development, then death will take on a whole new meaning.

      I belive that the meaning of life is arbitrary, that we humans believing that we are the most intelligent and advanced life form on the planet coined the term "life" associating characters to it like replication, response to stimuli, etc. That’s why we have so much problem classifying viruses, prions, etc; we don’t know exactly where to put them, living or non-living. In the face of this I would say that death is also a relative term; that it is a too short sighted event of life. Death is a stage in life not the end of it.

    • #52677
      James
      Participant

      Nice post, it puzzles me whether aging, cancer, DNA errors etc are really a result of ‘the battle with entropy’. They seem ideal processes to evolve in order to limit population size, which somehow could be evolutionarily beneficial. As for saying that death is a stage of life, that would support the idea that death has evolved wouldn’t it?

    • #52775
      xand_3r
      Participant

      Cancer cells have an altered cell cycle, having rapid division and lacking the mechanisms for apoptosys so we could say that they’re immortal. Anyway, if an organism lives long enough, even without an ageing mechanism it will eventually die because of negative mutations. Mitochondrion DNA cannot be repaired so well since it lacks the complex repairing mechanisms of eucaryotes (like the removal of timine dimers). So mutations in that DNA occur 10 times more often. Anyway, even with the mechanisms of repair, some mutations escape repairing, which in turn will lead to a more and more altered genetic material. If these mutations occur in the gametic cells, mutations will be passed to future generations. Maybe a reason for the existance of ageing mechanisms is to avoid the spanning of a more and more altered DNA.

    • #52970
      Linn
      Participant

      If we had no stresses, no illness, etc or anything "oxidizing" us to death, we would live much longer. there is no reason cell rejuvination should not be able to go on indefinetly.

      What do ya think?

    • #53136
      Dustfinger
      Participant

      Look. Nature has to keep itself existing, so what do you think would happen if endless hordes of bacteria, animals, human beings etc. would live on and on and reproduce ? Either the universe is endless (which we donยดt know for certain) or death of these living creatures will be the natural extension of life because the universe cannot "feed" all them.

    • #55941
      dyna_r
      Participant

      well, every cells, as the functional units of living organism precisely will die…

    • #55990
      geonyzl
      Participant

      well, just keep in mind that one character of a living organism that has its own life span. Life span would vary in different individual in each species. Life span would also depend on the kind of environment and its life style.

      geon

    • #60547
      Azedenkae
      Participant

      BTW, er… doesn’t bacteria NOT die?

      Some might, but basically when the time comes they just divide into 2 daughter Bacterias?

      Which is not really ‘dying’ but splitting into 2?

    • #60553
      sachin
      Participant

      8) Hmm.. Perfect thinking "Death EVOLVED?".

      I think this is great , Say from millions of years death is Natures rule.
      Nature have created diff. disease, antities, chronic damages for reason of death. but Organisms seems to be adapted for those conditions as generation goes on so Reasons of death need to be evolved to keep natures rule alive.

    • #60554
      nugget
      Participant

      This is quite an interesting thread, and the idea that cancer cells are immortal? … well i remember seeing a picture of a cancerous tumour that was "kept alive" for like ages and it just kept getting bigger. ill have a look for that actually.

      We cant be immortal, because like all things dna replication isnt perfect and death is probably a good thing or else we would be living for such a long time but with dysfunctional organs as our mutations would just accumulate!!

      We can either live as invalids, or die as we enter that stage !

    • #60580
      Dr.Stein
      Participant

      Every living thing will die..

    • #60678
      sachin
      Participant

    • #60717
      AstusAleator
      Participant

      I thought this thread was in the Evolution forum?

    • #60768
      Dr.Stein
      Participant

      @Sachin: Jaa, I love that Death Angel :mrgreen:

    • #60779
      sachin
      Participant
      quote Dr.Stein:

      @Sachin: Jaa, I love that Death Angel :mrgreen:

      Angel โ“ ๐Ÿ˜† ๐Ÿ˜† ๐Ÿ˜† ๐Ÿ˜› ๐Ÿ˜†

    • #60827
      Linn
      Participant

      Why does that have such symbolism on it? ๐Ÿ˜•

      Just wondering to myself โ“

      "And his sad unallied existence:

      To which his spirit may oppose

      Itselfโ€”an equal to all woes,

      And a firm will, and a deep sense,

      Which even in torture can descry

      Its own concentred recompense,

      Triumphant where it dares defy,

      And making Death a Victory."

      ~Lord Byron (1788-1824)

    • #60893
      James
      Participant

      Maybe the focus should be less on did death evolve as death is probably a process that is inevitable due to the biochemistry. Our DNA is constantly being repaired as much as possible, but is sometimes overwhelmed- thats due to the physics and chemistry.

      The question should be why, or did, ‘death by old age’ and specific lifespans evolve. Why is it that some animals die after reproduction is complete. Conversely, humans live unexpectedly long- possibly so grandparents can aid with their offspring’s offspring rearing. But why not go further? Surely the selfish gene would rather have individuals live as long as possilble. Or is that wrong?

    • #60903
      nugget
      Participant

      Because life is too tiring if we continued doing what we did double or triple the time we would be emotionally so tired dont you think?
      If the old was never regenerated into the new then there would be overpopulation. If there was overpopulation, resources would become scarce, and as corny as it sonds the circle of life would be disturbed. If old doesnt die the new will be at a disadvantage as a result of exploitation of the resources.

    • #60908
      Linn
      Participant
      quote James:

      Maybe the focus should be less on did death evolve as death is probably a process that is inevitable due to the biochemistry. Our DNA is constantly being repaired as much as possible, but is sometimes overwhelmed- thats due to the physics and chemistry.

      The question should be why, or did, ‘death by old age’ and specific lifespans evolve. Why is it that some animals die after reproduction is complete. Conversely, humans live unexpectedly long- possibly so grandparents can aid with their offspring’s offspring rearing. But why not go further? Surely the selfish gene would rather have individuals live as long as possilble. Or is that wrong?

      I really think we would live a lot longer if we did not have the oxidizing effect of stress damaging DNA. Some of which is self inflicted.

      One gov study showed that DNA was detrimentaly affected by volence.

      you will have to take my word about this cause I can not remember the name of the study ( A US government reserch project) Of the control group A > watched only violent movies for a period of time I cant remember, Group B only watched nice happy movies. I think there was an other group who just went about business as usual, Samples were taken before and after, Can ya guess the results? ๐Ÿ™‚

      We kill our selfish gene ourselves. ๐Ÿ™

      you said:

      quote :

      but is sometimes overwhelmed- thats due to the physics and chemistry

      .

      perhaps it could go on indefinetly. โ“

    • #61078
      AstusAleator
      Participant

      Hmm, recycled arguments, but still an interesting discussion. I was afraid that the thread had *died* :D.

      James, you touched on something important when you said circle of life. I know you were mainly talking about competition between young and old, and the necessity of the old passing on.
      However, there is a more important attribute of death, and that is nutrient cycling. We all know about food webs. Well, lets look at salmon for example. Salmon spend most of their adult lives in the ocean, where they attain most of their body mass. Then they return to the rivers and streams to spawn and die. This death is very important, not only for the next generation of salmon, but to every species living in the riparian zones the salmon reach.
      I recently read a study in which they demonstrated that significant amounts of nutrients derived from the ocean can be found in inland riparian vegetation as far as salmon reach. As a result, these riparian zones are healthier. The healthier riparian zones then have increased root mass and deadfalls in and across the water, providing refuge and nutrients for salmon fry. This is a positive feedback system that, bearing further study, could probably demonstrate that salmon death is an evolutionary trait.

    • #61173
      rob3
      Participant

      Maybe it was a "spandrel" of complexity, the maintenance of a complex organism is much more demanding that that of very early life (probably).
      Also, if organisma reproduce, and gradually became more adapted to a changing environment through generations, then their ancestors would not be so well adapted and may have to die. Also if reproduction and no death occurred at the same time, then the organisma habitat would become overpopulated.

    • #63932
      sachin
      Participant

      Thats why, I think death Evolved in fatal way..

    • #64503
      jimmystang
      Participant

      actually, on an idea related to death – aging and the gradual loss of function (e.g. fertility) is a part of evolutionary fitness.

      a species as a whole might actually be more fit if it could die and reproduce.
      i’ve a few ideas:

      1. Death and birth cycles through generations, creating genetic diversity, which is crucial for organisms like bacteria that need to evolve antibiotic resistance, for example.

      2. Death might be a result of a population reaching carrying capacity. The mortality rate increases as more organisms vie for the resources.

      3. Death recycles material for life. Carbon, phosphorus, nitrogen, etc, etc. are all crucial to survival. If a species didn’t die and help cycle on the nutrients, they’d consume all the nutrients and leave nothing at the end.

    • #65312
      sachin
      Participant

      Good scientific and Ecological Answer Jimmy.

    • #69444
      mattw
      Participant
      quote mith:

      Isn’t a cancer cell an immortal cell?

      Isn’t to say this a contradiction in terms?: The cells are "immortal" but they cause the death of their "host" organism. (Us.)

    • #69521
      Poison
      Participant
      quote mattw:

      quote mith:

      Isn’t a cancer cell an immortal cell?

      Isn’t to say this a contradiction in terms?: The cells are “immortal” but they cause the death of their “host” organism. (Us.)

      Cells are immortal because they do not go throught apoptosis. They cause death of the organism but they don’t do it intentionally. It’s just a result of the changes occured in cancer cells and their continuous division.

    • #69538
      AstusAleator
      Participant

      immortal means they dont’ die, but they do. They might not undergo apoptosis, but they CAN die.

    • #69650
      Poison
      Participant

      how do you define the death of a cell then?

    • #69699
      AstusAleator
      Participant

      cell death can happen many ways.
      Apoptosis is simply the programmed death of a cell.

      Cells can die from attacks by other cells/organisms
      cells can die due to a hostile environment (lack of nutrients etc)

      I’m no micro biologist, but I guess cell death could be defined as a cessation of function accompanied by destruction of the cell body.

    • #69914
      45561
      Participant
      quote James:

      I was thinking there could have been a situation where reproduction was hindered due to the inability for organisms to die, thus death was favourable.

      I think that it’s possible. Competition between parent and offspring may harm proliferation to some extent. If the parent dies, then it is no longer competing with its offspring (the parent is already developed, probably larger and may be cannibalistic), so the offspring have a better chance of survival and can go on to reproduce more quickly.

      It might be better to select against size than immortality, since there is a limit to how many organisms can survive in a space anyway, but evolution lacks foresight.

      It is good to ask whether or not longevity was limited early in life’s history. As suggested earlier, lava is pretty fierce. I think it more likely that the systems that allow long life conferred no advantage, and so if they did develop they were not selected for (rather than selected against), and so senescence was inevitable.

    • #73058
      amoebapower
      Participant

      as to what was said earlier, i dont believe viruses die because they are not techinically "alive" in the first place. for example chicken pox. once you get it, you dont get it again, although the virus has remained inside of you. only sometimes the virus flares up causing shingles. thus, viruses never die.

    • #73073
      Dustfinger
      Participant

      Are viruses living organisms now or not ?

    • #73088
      kotoreru
      Participant

      Nooo…they have no metabolism.

    • #77924
      mcar
      Participant

      Death is irreversible. That’s it.
      Evolution irreversible according to Dollo.
      Death is simply the end, evolution progresses.

    • #77940
      AstusAleator
      Participant

      And ironically the death of this thread doesn’t seem to be very permanent

    • #81312
      mcar
      Participant

      If this would be again connected with our relationship with God, it is more of God’s love for us. He let us experience death.

    • #81419
      tianlai
      Participant

      I suppose the first organisms are immortal, accurately they are organic polymers but not organisms. Today they are still living inside of all of the creatures, from viruses to whales. They are RNA, protein and DNA. Whatever the time goes on, they will keep their form till eternity.

    • #81420
      tianlai
      Participant

      God just exists in our meme but not in our real life.

    • #81487
      nibs02
      Participant

      I believe that death is inevitable. The first organism where simple, single celled organism unlike the complexities of humans and animals. Like someone stated earlier, they had some form of death by division in which the initial cell (call it patient zero or whatever) split into two new cells which then also split into new cells as well. You do have some form of patient zero’s existence in each new cell as it serves as a template during Mitosis but their type of death is completely different to us more complex organisms who grow by Meiosis.

      Also, for any time of evolution to occur, one of five stabilizing conditiongs must occur:
      1.) Genetic Drift
      2.) Genetic Flow
      3.) Mutation
      4.) Equal Success
      5.) Selective Mating

      If life did not evolve from a simple organism to one that’s complex, the reality as we know it would be filled with single celled organisms. Yet through their endless division and exposure to raw materials, evolution is inevitable and will always occur. I believe that life and death go hand in hand no matter what the organism.

    • #81510
      mcar
      Participant

      Death is experienced so as to end man’s fate to continue working and doing.

    • #82720
      Cat
      Participant

      I don’t remember who said this, but:

      Life cannot exist without death, just as death cannot exist without life.

      As soon as the first cell came into existence, it became susceptible to death by environmental factors. If you are talking about death by apoptosis, death did evolve (single cell organisms do not need it).
      Most (if not all) multicellular organisms require apoptosis. In order to look like anything but a big formless blob of cell, multicellular organisms need some of their cells to die in an ordered fashion (by apoptosis). Any time cells lose their ability to undergo apoptosis (like in cancer), they lead to disruption organisms overall function and can cause death.

    • #83013
      mcar
      Participant

      And as what I remember of cancerous cells–"immortal" as they may seem.

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