Why is an understanding of evolutionary and population processes important for species conservation?
Evolution is it a theory of previous life becoming more like present life over time through means such as "natural selection" With an endless diversity of life, and variation as a result of the interactions of organisms with their environments. Fundamental to the process of understanding how evolution works is to look at a combination of many mechanisms such as genetic variation, natural selection, adaption, mutation, gene flow, genetic drift and variation, sexual selection, fitness and genetic descent. The objectives of this paper aim to firstly look at all of the mechanisms within evolution, secondly to then look at any changes in the size of species populations and thirdly to see if having an understanding of all the mechanisms and how they can affect species populations can we have a better understanding of conservation.
1.0 Major mechanisms leading to evolutionary change
Natural selection is one of the basic mechanisms of evolution, and is a necessary process for change but it alone doesn't define evolution. The important and underrated force at play is expansion. In order for evolution to occur natural selection must eliminate organisms unsuited for the environment, Mayr (2001) points out "At the first step, that of production of genetic variation, everything is a matter of chance, the random generation of new genetic subjects creates the diversity which then can undergo selection”. Darwin's views on evolution by natural selection are very simple in the Origin of Species (1859) he makes the point that “The principle by which each slight variation [of a trait], if useful, is preserved"
Alongside natural selection, mutation, and migration, genetic drift can be classed as one of the basic mechanisms of evolution. Genes that are passed down to the next generation are not always going to be the genes of the healthiest individual, sometimes it is just pure luck, or in other terms genetic drift. This type of genetics is completely random and although like natural selection it changes the genetics it does not create adaptions.
Adaptations take place by improving a specific function and are a form of natural selection. A single organism cannot evolve within its own life span because of environmental pressure. Therefore, one organism cannot possibly experience evolution in action as a result of environmental interactions. Adaptation can lead to some confusion at this point as it is so often connected with evolutionary change and denotes a change that is more suited for certain environmental conditions. Evolution, along with adaptation arises through many generations. Changes to a species cannot directly be related to the conditions of the environment. Nor can it trigger a change, as they will occur secondarily. Selection cannot be classed as predestined within a species though as it already exists characteristically from birth. Mayr (2007) explains this, and writes, "Selection does not have a long-term goal" and "evolution is not deterministic"
Mutation can be classed as a change in the DNA of a certain species. DNA will have an effect on how certain species will look, behave, and will also determine its anatomy. If there are any changes in a species’ DNA changes will occur within all aspects of its life. Mutations are always random and can either be harmful or helpful for a species. If a mutation does take place it does not always mean that it will be beneficial for that species. All cells within a species contain DNA, so there are many places for a mutation to occur. It is worth noting that not all mutations will affect evolution. Mutations that will affect evolution take place on a much larger scale and will be passed onto the next generation through the eggs and sperm of the parent. This type of mutation affects the species in a number of ways by changing the phenotype (amino acid change)...
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