Survival is one of the things organism work for in their existence. Each one of us have the desire to leave a part of ourselves in the worldto make our markso that we can tell ourselves that we have done something significant or there is some importance to our existence. This is why the ability to reproduce is also an important factor in our lives the capacity to pass on our traits, to make it fit enough to survive.

Time, selection, and change are some of the components of evolution. In Darwins study, he was able to conclude that organisms have the ability to create more offspring than what the environment can support, and each of the offspring owns a unique trait. A number of them may possess combinations that enable them to survive and reproduce. These different traits are acquired in the combination of genes in the process of reproduction and mutation.

The selection of traits that survive is a function of the environment where the organism lives, as the theory on natural selection asserts. To quote Herbert Spencers words, This survival of the fittest, implies the multiplication of the fittest. . . This survival of the fittest. . . is that which Mr. Darwin has called natural selection, or the preservation of favoured races in the struggle for life, the term fittest in this equation does not pertain to those who have good physique and health, this refers to the specie who carry the genes suited for its environment and who is able to pass it on through reproduction, which in turn allows them to survive.

Apart from their ability to reproduce and spread their traits, other factors have an effect on a species survival in its environment. This may come in the form of pH changes, temperature, food, the species they interact with, and the like. Although it may appear that physical traits are essential in survival, it must be noted that these traits will be useless if the specie or organism is unable to pass on this qualities.

This is illustrated in the case of the two male crickets who are trying to find a mate. The first cricket has all the attributes of what a lady cricket would desire. He is described as big, healthy. . . strong, confident, and looking for love, and to add to this, this cricket has the ability to sing or call. The second cricket has different attributes altogether. He is silent. Considering the attributes both crickets have, we can say that fitness depends on the environment the cricket is situated a location with less or more predator. A good or bad genetic makeup does not guarantee that one is the fittest although the ability to adapt to ones environment is a plus. Fitness is present for the cricket that is able to reproduce and pass on traits to their offspring.    

Calling is both good and bad for a male crickets fitness. It all depends on the environment he is situated. Two things results from the ability to call the prospect of attracting female crickets, and the misfortune of being prey to predators. Since fitness is described as the ability to multiply and pass on the gene, then, the skill to call by normal crickets is seen as positive since calling is an essential trait in order to get a female crickets attention. Calling is followed by a courtship song, which lures the female into mating (Understanding Evolution). However, in an environment infested by predators who can hear the call as well, the scenario seems unfavorable for this type of crickets. Calling will reveal the cricket to its predators, which can result to his death depending on the other traits he carries (extra strength or speed in running).

Three examples of natural selection can be found in the cricket story. In an environment with lesser predator, natural selection will favor the calling cricket. They have the advantage to call and attract a female mate. This will result to more offspring with calling traits, and there will less number of the silent types. Even though they may be able to intercept the mating of the noisy cricket, chances are the calling cricket will still be the majority in that island since females will less attracted to the silent ones. On the other hand, a location filled with predators works otherwise. Natural selection will favor the silent crickets. Noisy crickets will reveal their location to predators like the bats, and chances are they would get eaten as compared to silent crickets, they will be able to hide from the bat and get a chance to find a mate some other time. Though much advantage is given to the silent crickets in this scenario, they are still dependent on calling males to attract female crickets and intercept their mating. Still, in this situation, advantage is with the silent cricket they will remain the majority for this instance. Natural selection is also present in the existence of the environment. The environment is the one who chooses which to favor. It is not in the characteristics or trait of the cricket noisy or silent. It is the environments make up who decides which trait to favor, and thus, who survives.

The natural selection occurring in the story is directional selection. Directional selection occurs when there is a shift to one extreme more or less, noisy or silent. Natural selection has to favor one of the extremes in a situation. In this case there are two extremes, the calling cricket and the silent cricket. In cases where there is less predators, the natural selection goes to the direction of the calling cricket since they will be the fit organism. When there is more predators, there will be again one shift to the other extreme, the advantage is now with the silent crickets.

As aforementioned, the environment plays a vital role in deciding who will survive. In an area filled with predators, most likely there will be lesser calling since the dominant trait in that area are the silent types. The situation may be that most of the calling types are eaten by the predator, and this was observed in Kauai crickets. Since there were many flies in the area and these flies drops maggots on crickets to feed on them from the inside, calling crickets will be the regular target for them. This decreased the population of calling crickets resulting to more silent crickets in the area. For areas with no or less predators, there will be more cricket calling since the chances of being food to predators is less and female crickets are attracted to calling crickets as compared to the silent ones. The genetic makeup of silent cricket will be a minority in the area.


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