It has taken more than five decades, but the electronic computer is now powerful enough to simulate evolution.
Researchers from Michigan State University have used software to prove Charles Darwin's postulation that small, seemingly inconsequential changes over thousands of generations can result in the evolution of complex functions.
They also uncovered a twist on conventional evolutionary thinking -- it seems that some mutations that are harmful in the short run may boost long-term potential.
... When digital organisms were rewarded for solving simple puzzles with more CPU time -- and thus an increased ability to send their genes forward to future generations -- they eventually evolved a way to solve even the most complex problem they were challenged with, said Lenski.
The researchers' results also show that this is the only way organisms can evolve, said Lenski. "Calculations imply [that] the probability of the digital organisms getting that complex all at once is astronomically small," he said.
The birds-eye view on evolution also showed a twist, said Lenski. "Biologists usually assumed that the evolution of new mutations is an uphill climb -- one in which the winners are descended from the most fit organisms in earlier generations, rather like a mountaineer that is always moving up -- or at least sideways," he said.
The researchers found that among the ancestors of the eventual winner, some had mutations that were harmful in the short run. Taking two steps back sometimes provided a better route. "Some of these harmful mutations worked well in combination with other mutations that came later," said Lenski. So while most deleterious mutations were eliminated, some were passed on, turning a short-term handicap into a long-term advantage as the subsequent evolution unfolded, he said. - trnmag
In other words, it is highly likely that previous human species were more adanced in some ways that we are today. (For example, some may have had perfect memory. Others, amazing strength. Some may have been able to turn sugar into vitamin C....) In the future we may have samples of DNA from other human species we can use in hacking our biology.
Well, in the example above we had computer programmers who were "God" and they supplied the reward (CPU time). Doesn't this prove by analogy that we have a God who supplied the reward (energy for reproduction and survival in a hostile environment) for the creation of humans?
The fairly new science of self-organizing systems has in part answered this. It is the small local rules, for example, charges which cause atoms to partially attract or repel, which eventually lead to large scale complexity. Once you have sufficient complexity along with random change, feedback loops emerge.
Complex systems with feedback loops that allow for self-renewal are called autopoietic structures. One example of a simple, self-organizing system is a whirlpool. Another example is the red spot on the planet Jupiter.
Simple autopoietic structures interact with new rules and eventually become more successful at reproducing, and thus, you get...
Other systems, such as the human body, can be extremely complex (Briggs and Peat, 1989). - Read More About Feedback Loops
PS. Here are some "artifical life" programs you can play with.
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