The major mistake humans make in understanding competition in nature is that they assume that if an animal is competing, then it must do so because it is struggling and suffering. However, in nature most animals compete because they can, to feel fulfilled, or for the fun of it. Competition in animals arises out of a desire to win and achieve. That is very different to competition that arises out of a dire need to conquer the struggle. Nature may seem to be highly competitive, but that competition can just as easily arise from a desire to win as from a fear of losing. I realize here that humans will find this a difficult concept to understand. They are now so brainwashed into looking at nature as a place of struggle. I could argue and give an example one way, and a dutiful biologist could counter with another. Nature has such variety, that almost any opinion can be 'supported' with the 'evidence'. At some time you will need to develop a wild sense for what is real in nature.
So which way is it for most of the time in nature? For the answer, you should look more closely at the health of the competitors to see if from their point of view, life for them is easy or a competitive struggle. To do this, compare the health of animals and humans. Both compete, but which one does so out of struggle and which out of a desire to win? Animals tend to compete in a light-hearted way. They are easily fought off during displays. They are mainly bluff and display. They are a bit like an explorer who strives to be the first to climb a mountain. They do it because it is there and they feel free and daring enough to take the plunge. Therefore, animals usually suffer only minor stress during competition. Of course, exceptions can be found, but I am talking about most of the time. This compares to humans who suffer greatly from the stress and struggle of their daily competitive lives. They suffer from anxiety, constipation, disease and mental illness. They take drugs to escape their stress. They become trapped and suppressed within their system of competition, rather than knowing how to stay filled with a sense of wildness and freedom.
Humans periodically attempt to raise the standard of their competition closer to the way nature intended, by playing sport. Then they can compete for fun, and according to rules and rituals, in a similar vein to those that are so widespread throughout nature. Of course, they often take their sport too seriously, especially when money is involved or when they allow their pitiful sense of struggle to get the better of them. Humans are often overly competitive and forget the spirit and lightness of 'the game'. Hopefully one day, humans will find the strength of character needed to make the spirit of their competition match that found in other animals. Then they will learn how to 'compete' in a manner that places less stress on their lives.
Competition is another instinct that does not need to be inherited, but can arise from natural interaction. If there is a shortage of some kind, the simple need to fulfill a desire will make an animal seek the prize, sometimes to the point of active competition. The animal will learn the degree to which it must compete to win. It will also learn the costs associated with competing, and therefore, when it is better to back away or leave. Of course, signs that animals actively seek to fill their desires are widespread in nature. Animals will fight or contest over food, mates or territory. One way animals avoid continual fighting is to establish a hierarchy, where all learn who is dominant over another. Hierarchies allow animals to avoid continual fighting during periods of competition. Instead, they can put their efforts into rituals and displays, or bouts of strength. There is not much fun in actually getting damaged.