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Do Celestial Objects Compete for Matter?

  1. Feb 14, 2006 #1
    Space is an ecosystem. Objects compete for matter. An asteroid slams into the Moon, and is pulverized. It loses its identity. But the Moon remains the Moon, but with a new pockmark--and it gains more matter to make it even more powerful. But sometimes, things eat too much, like supermassive stars. They are not very fit because they explode from indigestion after just a few million years. Obesity kills. Luckily for most of the matter in the universe, there is the law of inertia. This creates a level playing field that prevents the smaller items from getting directly sucked into the the larger players.

    The competition for matter by planets, stars and galaxies is a form of natural selection in a nonliving domain. Which would seem to entail that celestial objects are adapted entities in the biological sense. Thus, the boundary between biological and the physical sciences is dissolved not by reducing biology to physics, but rather by supersizing physics to include the biological principles of natural selection and adaptation.
  2. jcsd
  3. Feb 23, 2006 #2
    I don't know.Only living things would have that kind of behavior.
  4. Feb 24, 2006 #3


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    How do reproduction and inherited traits fit into this argument? In order to produce something like biological complexity, the survivors must pass something on to future generations. In the case of stars, it's the opposite -- the ones that blow up pass on their metals to future generations. In the case of planets, we think the formation happens all at once, so there would only be one generation.
  5. Feb 24, 2006 #4


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    What you are describing is not a form of selection at all. (For example: The existence of moons does not facilitate or even encourage the creation of more moons.)

    What you are talking about is more accurately described as a positive feedback loop: a natural process creates conditions that accelerate the process. The opposite is a negative feedback loop, where a process creates conditions that defeat the process.

    An example of a positive feedback loop is that of cliff erosion due to frost heaving. Tiny amounts of water freeze in cracks, widening them, allowing more water in, encouraging more calving. Eventually, whole cliff faces can be reduced to rubble.

    An example of negative feedback is the freezing of ice on a lake. As the surface of the lake freezes, it insulates the lake from extremes in cold, thus discouraging further freezing.

    The reason stars and planets are a positive feedback process is because gravity is a one-way process.

    What you put forth is an interesting philosophical viewpoint, and there's no doubt that looking at common processes in nature - both living and non-living - is cool. But don't mistake it for anything other than a metaphor.
    Last edited: Feb 24, 2006
  6. Apr 15, 2006 #5
    Reproduction is not necessary for natural selection to occur, even within biology. When a bryazoan expands at the expense of a sponge, that is natural selection, but without reproduction. True, reproduction and inheritance are apparently required for the hypercomplexity exhibited by life. Nevertheless, we must not conflate evolutionary constraints with lack of natural selection. Besides, when your life span is 4 billion years, why bother to reproduce?

    All language is metaphor. Therefore, there are only good metaphors, and not-so-good metaphors. We say light is a particle or a wave, but these are metaphors. We use mathematics to describe physics, but that is also a metaphor. If we use continuous mathematics to describe space, does it follow that space is really composed of infinitesimal points? If a plant is nothing but atoms and molecules, is it really alive? Or is it just working properly? Is the Cassini space probe really dead?

    In science, a metaphor is as good as the new results that can be obtained. I can think of at least one Nobel-prize winning example of a team of chemists that applied biological metaphors to their subject matter: the Rice University team that discovered buckminsterfullerene realized that the C60 molecule formed within an arena where "voracious" carbon molecules competed with each other. Only the stablest survived, and that realization enabled them to do a biological-like functional analysis of C60, and they were able to quickly zero-in on the soccerball structure for which they won the Nobel.

    Brave is the pine that changes not its color, bearing the snow.
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