Visualize Evolution

By Anthony | February 5th, 2007 | 12:15 am

One of the principle factors in evolution is the random mutation of genetic code. This often leads to the misconception that evolution as a whole is totally random, but that isn’t the case. Selective pressures, such as natural selection, are a non-random “guiding force” in the process of evolution. Natural selection is what turns those random changes into increasingly useful traits that help a species to survive.

Here are a couple of simulations that illustrate the effects of selective pressures. The first simulation (via Pharyngula) is in the form of a game that runs automatically in your browser. Organisms take the form of strings of code that represent positions on a game board. As the game plays itself out, various positions are evaluated for fitness based on how well they score, and are kept or discarded accordingly – natural selection in action. The successful positions are then recombined with mutations based on real-world genetic mutations, and this new generation is then tested. As the game continues, you can see the population becoming more “fit” as the scores increase.

This particular simulation also provides an interesting rebuttal to the ID notion of Irredcuible Complexity – the idea that certain biological structures could not have evolved because the removal of any one part renders the structure useless. As the “organisms” in the game evolve and are tested for fitness, they are also tested for Irreducible Complexity. Any board position that has five or more components and is rendered “unfit” by removing one component is flagged as Irreducibly Complex – undercutting the claim that evolutionary processes can’t produce such structures.

Give the simulation a try and see what you think.

I found the second simulation while surfing through links and comments from the original Pharyngula post. This one is a youtube video that uses a couple of clever demonstrations to show the power of reproduction under selective pressure:

3 Responses to “Visualize Evolution”

  1. Jim Caserta Says:

    Both simulators are pretty simplistic, with the picture one being more convincing. Living things are about 1,000,000,000x more complex than those computer programs. The picture one is interesting because they have a picture they are moving towards, without a goal, that simulation would behave much differently.

    Genetics is the basis for evolution, but no one doubts its tenets – because they are testable. I was reminded recently who the father of genetics is – Gregor Mendel, an Augustinian monk. The Catholic university my dad attended honors him by awarding a Mendel medal – After a shaky start, there was a period where the Church was a strong partner with science, and I do not see any reason why that should not be.

  2. PotatoStew Says:

    Thanks for the comment Jim. I agree that the simulations are pretty simplistic. Living things are so complex that I doubt we’ll ever get close to realistically modeling them. For what it’s worth, there are more complex programs out there such as Avida. But I think the main point is that it is possible for order and complexity to evolve in a self-replicating system without specific guidance from an intelligent being. The demonstrations show that, albeit on a simplistic level.

    As for the picture one, it *is* slightly misleading that there is a specific goal in mind for the end product, since evolution isn’t really directed towards a specific goal. It’s helpful to think of the target picture in this instance as something like “a form which is ideally suited to the environment” rather than “what we’d like the end product to be”. It’s just a convenient way of providing selective pressure.

  3. meblogin Says:

    “But I think the main point is that it is possible for order and complexity to evolve in a self-replicating system without specific guidance from an intelligent being.”

    then again….an intelligent being can be behind it all….

    That makes great sense to me.

    Cool post.