A Fun Experiment with Darwin's Theory of Natural Selection
In 1859, one book, which is regarded by some as the most important writing in the natural sciences, was published and Charles Darwin became a figurehead of the scientific community. With The Origin of Species, Darwin argued that natural selection is the driving force behind the development of different "varieties" of the same species, as well as for both the extinction or success of a group of animals. This was his attempt to create a unifying law with which to explain the biological world, much as Newton had done for the physical world, though his theories cannot, like other reductionist works, be proven through mathematics. A simple experiment can, however, serve as model for Darwin's work by displaying a very base form of natural selection.
The experiment is executed as follows: Lay out a piece of patterned fabric. Take small pieces of colored paper. Scatter the paper over the fabric and commence in removing the first pieces to catch your eye.
Imagine that the fabric is a given environment, that the paper pieces are insects and that the removal of the most eye-catching pieces represents a predator eating those insects. By creating "generations" the effects of natural selection on a population are displayed in an accelerated model. The idea is that by the end of the third generation, only one color will remain on the fabric and all of the others will have been "eaten," thus proving that species ill-suited to the environment in which they live are weeded out by the forces of nature.
There are a number of problems with this experiment, however, the first being that it is designed to produce predictable outcomes while, in nature, the results of natural selection are highly unpredictable. In fact, when the experiment does not produce only one color of "insect" it is more closely mirroring nature than the desired outcome.
My personal results showed that on a darker, yet saturated print, the majority of remaining pieces were greys and browns, and although blue and purple were not entirely eliminated, the pink and bright green "insects" suffered extinction within the first two generations. Similarly, in nature, some species will be entirely incompatible with a certain environment and completely die out, while several others maintain small and scattered populations; one or two species remain dominant and thrive in that area due their superior design.
Of course there are problems with these results as well; they take into account only external appearances with respect to predators. The fact that darker and more muted colors were, in other experiments as well, the least likely to be removed from the environment reflects that specie's ability to avoid detection. Unfortunately, this level of inconspicuousness would have detrimental effects on sexual attention as well, which Darwin notes as especially important in nature; he cites certain varieties of birds, which rely almost solely on impressive displays of plumage to win over a mate. This standard of beauty plays just as vital a role in natural selection as the ability to avoid being eaten, since, although an individual may survive, without procreation, that individual's characteristics and genetic composition will not be passed on to the next generation.
Thus far, the only examples of natural selection given have been based entirely on outward appearances, which while playing a very important role in the ability of a species to procreate and persevere says nothing about variation. Variation, simply stated, is the tendency of a species to develop, and change in a manner which better serves its survival. Characteristics which prove useful are propagated, and after a time, become part of the standard build of a species, while characteristics which are either detrimental, or serve no real purpose, tend to disappear. In the midst of this adaptation to the surrounding environment, it is not unlikely that a new variety of a particular species will develop. Darwin states that although "Our ignorance on the laws of variation is profound...whenever we have the means of instituting a comparison, the same laws appear to have acted..." Clearly, no such laws act upon the paper cutouts of this particular experiment, which is unfortunate, since variation plays such a large part in the process of natural selection.
A more advanced accelerated model would have shown a number of possible variations. For example, the larger specimens were consistently easier to detect and therefore, more readily consumed. Had the laws of variation applied, the following generations would have produced increasingly smaller offspring until the species had reached a somewhat homogeneous and ultimately advantageous size, at which point, there being no need for continued shrinkage, this variation would reach a sort of balance with the environmental factors. Additionally, these variations would most likely occur in the less dominant varieties of insects in the area, which would give those individuals a better chance of survival as well as there being a potential for a new insect to develop.
In the attempt to prove Darwin's theory of Natural Selection, it becomes clear that nature itself provides too many variables and that the selection process is, as Darwin suggests, a very slow process, often taking place over numerous human generations. Though examples have been noted using the animals of breeders, that is, most undeniably, an unnatural form of selection, and therefore, cannot be used as hard evidence. There is simply no practical way to create a model or conduct an experiment which proves the theory without a doubt. It must be through a great deal of conjecture and the substantial amount of evidence gathered from various sources, that Natural Selection be understood.
Do You Know Your Darwin?
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