Are Apples Alive?

Oct 25 2011 Published by under Uncategorized

Here's where we get to some interesting questions on what is life.

Chapter 2 - Question 3

Is an apple – hanging on a tree – living? When it falls to the ground – is it still living?

This isn't a silly question

Wow, now we get to the meat of it. And this is where I start to have fuzzy thoughts on the subject. It all depends on how you define ‘life’. If reproduction is a requirement for life, then the cell in the apple are probably alive, but the apple itself is not. The seeds are the result of reproduction in the parent tree, not in the apple it self.

This article relates an interesting story about that.

What is the definition of life? I remember a conference of the scientific elite that sought to answer that question. Is an enzyme alive? Is a virus alive? Is a cell alive? After many hours of launching promising balloons that defined life in a sentence, followed by equally conclusive punctures of these balloons, a solution seemed at hand: “The ability to reproduce—that is the essential characteristic of life,” said one statesman of science. Everyone nodded in agreement that the essential of a life was the ability to reproduce, until one small voice was heard. “Then one rabbit is dead. Two rabbits—a male and female—are alive but either one alone is dead.” At that point, we all became convinced that although everyone knows what life is there is no simple definition of life.

To use the classic definition of life that I was taught many, many moons ago. Life has these characters: Composed of cells, has metabolism, grows, adapts, responds to stimuli, reproduces, and maintains homeostasis.

I kind of like that definition, but an apple is not alive by this definition. The cells within it are, but the apple itself does not grow, reproduce, respond (except chemically), or has a metabolism.

Can we separate the living thing from the cells it is composed of? i.e. if the cells reproduce, does the organism? If the cells retain metabolism, does the organism?

I ask because a dead organism may have most of its cells function even after the organism itself dies… at least for a little while.

Which brings us to another question, that maybe we should consider first.

Chapter 2 - question 1

Do you believe in the utility attempting to give a definition of life?

I do think that there is utility in dealing with this question now. Avida organisms can already evolve complex logic functions. And computers are beginning to approach the computing power of the brain (cat brains first) and the human brains processing abilities.  (I will note that there is some skepticism on whether IBM has actually reached the equivalent computing power of a feline.) With that in mind, the question of what is alive will become very important… or maybe not. Humans have an unfortunate tendency to use resources and organisms regardless of the ethical considerations involved.

Life is like porn (you knew I was going there right?).  We might not be able to define it, but we know it when we see it... or do we.  Avida organisms are something that's pretty close to any reasonable definition of life, but they are definitely not made of cells.  Could there be other non-cellular life that we would just ignore because we don't see cells?

So what are the qualities that life must have to be considered life?

Honestly, I've been thinking about this for several months (in those 12 seconds between when I can finally lay down and when I actually go to sleep... otherwise known as 'spare time').  It is extraordinarily difficult to develop a definition of life that does not have some exception.  The apple above for example.  Combinations are even trickier.

I have placed an additional burden in that I think that digital organisms could eventually be alive.

11 responses so far

  • scicurious says:

    I have...never actually thought about this.

    *mind boggles*

  • gerty-z says:

    I absolutely LOVE this post. I think about this a lot-but often in the context of what is the difference between an organism the moment before it is alive and the moment after it has died rather than in how you determine if something is alive in the first place. Defining life is hard, but it is equally hard to define when something has ceased to be alive.

    well done!

  • I can't take all the credit Luisi is pretty intense.

    But there's a good reason for this... how can we discuss the chemical origin of life until we actually know what counts as life?

  • Pascale says:

    My head is going to explode...

  • _Arthur says:

    Most "fresh" fruits and vegetables are made of still-living cells, so, yes, the apple in the fruit bowl is alive.

  • Eugen says:

    My life is a fruit bowl.

    Good job Ogre - Kevin.

  • Joe G says:

    Is a man's semen alive? How about a woman's egg? An apple is a vital part of the tree because witout them the tree doesn't reproduce- the apple contains the seeds and the fruit is the fertilizer- or it attracts animals who eat it and scatter the seeds.

    Got that? An apple is part of a living organism.

    Living organism:

    1- Must contain a genome (Yockey)

    2- Must be able to or have come from reproduction

    3- Response to stimuli (yes plants respond to stimuli)

    4- metabolism

    5- Growth

    6- composed of one or more cells

    7- adaptation

    8- homeostasis

    What exceptions?

    Yes if you have only one rabbit, then soon enough you won't have any. But until it stops leaving coco-puffs around it will definitely be alive.

    • Meghan says:

      In fact, that is not necessarily true. In fact, once something itself has died (not the cells within them in all cases) the body stops being tense, and the bowels are loosened. So, if a being has not had a bowel m0vement before their untimely death, they would "leave coco-puffs" specifically because they were dead.

  • Renee Marie Jones says:

    Ya. I never bought the business about life being defined by ability to reproduce. Nope, don't buy it.

    I think life is like a lot of things, we think of it as a binary choice: something is alive or dead, with no other possible outcome. But this is arrogance. It assumes that we can define perfectly and it assumes that our definitions can anticipate all possibilities. We are not that perfect.

    It is the same mistake that creationists make. They think that one can define a "chicken" and that there must be a sharp dividing line between what is a chicken and what is not.

    We can define a chicken. We can talk about them, we can recognize them, we can roast them on a spit. However, in the vast history of chickens, there will be some in-between things that are kinda like chickens and kinda not like chickens and we won't be sure if they really should be chickens or if they should be called something else. This is ok. This is how the world works.

    We need to give up our need for sharp, absolute dividing lines. I am alive, the parrot I live with is alive, so is the ant crawling across the floor. Then there are other things: rocks and baseballs and puffy white clouds. They are not alive. And then there are the things in-between, the things we can't be sure of. A virus. A raw strand of DNA or RNA. An apple that has fallen from the tree.

    In-between is OK. Our definitions don't have to be perfect, just useful. Just try to remember that they are not perfect, and don't try to fit everything into binary categories.

  • Gerald says:

    "We can define a chicken. We can talk about them, we can recognize them, we can roast them on a spit. However, in the vast history of chickens, there will be some in-between things that are kinda like chickens and kinda not like chickens and we won't be sure if they really should be chickens or if they should be called something else. This is ok. This is how the world works."

    No matter what they are called, they will still taste like chicken....