From previous posts I and reading I have come to understand that a mutation is a precursor to natural selection. Now my question is why would Nature cause mutations ?. Say for example a human was born to be abnormally huge yet his life span would be shortened due to the side effects of being so big. Why has nature caused a mutation if the animals or humans life be so short lived ? it seems such a waste ?
It seems like you're thinking that nature deliberately causes mutations with some pre determined goal in sight. Mutations just happen - sometimes they help, sometimes they dont make a difference, and sometimes they are detrimental.
Well it seems that way its either to adapt the organism to a changing environment or create a "freak accident of nature" which wont last more then a generation. Why would nature create freak acidents ? perhaps this is an accident like defects at a car assembly plant ??
Well my point was that nature doesnt deliberately causes mutations with some pre determined goal in sight, such as trying to adapt to a changing environment. The mutations just occur. And when the environment changes, those with characteristics that are beneficial in the new environment stand a better chance of survival. And those with characteristics that are detrimental in the new (or current) environment stand a better chance of dying out.
Why can't it occur randomly? Presumably the process by which DNA replicates itself, for example, isnt completely perfect/foolproof. Its a complex process which is possible to cause some errors along the way. And sometimes the environment itself (eg radiation) can cause disruptions in the process resulting in errors.
There is also radiation, which damages DNA, and mutagenic compounds in our food. This is one reason most species limit their food sources. Omnivores are exposed to more mutagens.
You talk about nature as though it is a sentient creature, with goals and an agenda. Nature is nothing more than a set of laws that govern the behavior of the universe, and everything that happens conforms to those laws. Whether or not events happen at random is a question that has not yet been answered; it hinges on our very incomplete understanding of nature's laws, particularly at the scale of elementary particles. But whether or not there is a random component, there is certainly no purpose involved. Nature has no consciousness and is totally indifferent to the fate of her creations--alive or not. The laws of conservation of matter and energy ensure that nothing is wasted. What you're looking at is the organization of matter and energy. And one of nature's laws, the Second Law of Thermodynamics, assures us that the organization in the universe will decrease inexorably over time. The opposite of organization is entropy, and entropy will continue to increase until there is no organization anywhere in the universe. Life has been succinctly defined as "a local reversal of entropy," since (arguably) the most important of its defining characteristics is indeed that living things steadily increase their organization throughout their lives, at the expense of disproportionately decreasing the organization of their local environment. For example, a plant grows larger every day, slightly increasing its organization, but only by extracting solar energy from its environment for photosynthesis, reducing the temperature of the environment and causing a much greater decrease in its organization. A local reversal of entropy results in an overall increase of it. So to mourn the loss of a life is to resent the increase of entropy and the eventual reduction of the universe to a state of complete disorder.
