1 Evolution VS Mutation ( Meaning, definition, description )

Evolution

Evolution (or more specifically biological or organic evolution) is the change over time in one or more inherited traits found in populations of individuals.^[1] Inherited traits are distinguishing characteristics, for example anatomical, biochemical or behavioural, that are passed on from one generation to the next. Evolution requires variation of inherited traits within a population. New variants of inherited traits can enter a population from outside populations, and this is referred to as gene flow.^[2][3][4][5] Alternatively, new variants can come into being from within a population in at least three ways: mutation of DNA, epimutation (a change inherited in some way other than through the sequence of nucleotides in DNA), and genetic recombination. Natural selection, where different inherited traits cause different rates of survival and reproduction, can cause new variants to become common in a population.^[1] Other evolutionary mechanisms can cause a variant to become common even if the variant does not directly cause improved survival or reproduction. These mechanisms include genetic hitchhiking, genetic drift^[6][7], and recurrent biased mutation or migration.
Evolution has led to the diversification of all living organisms from a common ancestor, which are described by Charles Darwin as "endless forms most beautiful and most wonderful".^[8] For example, evolution is the cause of speciation, whereby a single ancestral species splits into two or more different species. Speciation is visible in anatomical, genetic and other similarities between groups of organisms, geographical distribution of related species, the fossil record and the recorded genetic changes in living organisms over many generations. Common descent stretches back over 3.5 billion years during which life has existed on earth.^{[9][10][11][12]} Both evolution within populations and speciation between them are thought to occur in multiple ways such as slowly, steadily and gradually over time or rapidly from one long static state to another.
The scientific study of evolution began in the mid-nineteenth century, when research into the fossil record and the diversity of living organisms convinced most scientists that species evolve.^[13] The mechanisms driving these changes remained unclear until the theory of natural selection was independently proposed by Charles Darwin and Alfred Wallace in 1858. In the early 20th century, Darwinian theories of evolution were combined with genetics, palaeontology and systematics, which culminated into a union of ideas known as the modern evolutionary synthesis.^[14] The synthesis became a major principle of biology as it provided a coherent and unifying explanation for the history and diversity of life on Earth.^[15][16][17]
Evolution is currently applied and studied in various areas within biology such as conservation biology, developmental biology, ecology, physiology, paleontology and medicine. Moreover, it has also made an impact on other disciplines such as agriculture, anthropology, philosophy and psychology. Evolutionary biologists document the fact that evolution occurs, and also develop and test theories that explain its causes.
The theory of evolution is a naturalistic theory of the history of life on earth (this refers to the theory of evolution which employs methodological naturalism and is taught in schools and universities). Merriam-Webster's dictionary gives the following definition of evolution: "a theory that the various types of animals and plants have their origin in other preexisting types and that the distinguishable differences are due to modifications in successive generations..."^[2] Currently, there are several theories of evolution.
Since World War II a majority of the most prominent and vocal defenders of the evolutionary position which employs methodological naturalism have been atheists.^[3] In 2007, "Discovery Institute's Center for Science and Culture...announced that over 700 scientists from around the world have now signed a statement expressing their skepticism about the contemporary theory of Darwinian evolution." [via wikipedia]

Mutation

A mutation is a permanent change in the DNA sequence of a gene. Mutations in a gene's DNA sequence can alter the amino acid sequence of the protein encoded by the gene.

How does this happen? Like words in a sentence, the DNA sequence of each gene determines the amino acid sequence for the protein it encodes. The DNA sequence is interpreted in groups of three nucleotide bases, called codons. Each codon specifies a single amino acid in a protein.

In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic chemicals, as well as errors that occur during meiosis or DNA replication.^[1][2][3] They can also be induced by the organism itself, by cellular processes such as hypermutation.
Mutation can result in several different types of change in sequences;(DNA) these can either have no effect, alter the product of a gene, or prevent the gene from functioning properly or completely. Studies in the fly Drosophila melanogaster suggest that if a mutation changes a protein produced by a gene, this will probably be harmful, with about 70 percent of these mutations having damaging effects, and the remainder being either neutral or weakly beneficial.^[4] Due to the damaging effects that mutations can have on genes, organisms have mechanisms such as DNA repair to remove mutations.^[1]
Viruses that use RNA as their genetic material have rapid mutation rates,^[5] which can be an advantage since these viruses will evolve constantly and rapidly, and thus evade the defensive responses of e.g. the human immune system.^[6]

A Mutation occurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene.

Mutagens Chemical Mutagens change the sequence of bases in a DNA gene in a number of ways;

• mimic the correct nucleotide bases in a DNA molecule, but fail to base pair correctly during DNA replication.
• remove parts of the nucleotide (such as the amino group on adenine), again causing improper base pairing during DNA replication.
• add hydrocarbon groups to various nucleotides, also causing incorrect base pairing during DNA replication.

Radiation High energy radiation from a radioactive material or from X-rays is absorbed by the atoms in water molecules surrounding the DNA. This energy is transferred to the electrons which then fly away from the atom. Left behind is a free radical, which is a highly dangerous and highly reactive molecule that attacks the DNA molecule and alters it in many ways.
Radiation can also cause double strand breaks in the DNA molecule, which the cell's repair mechanisms cannot put right.
Sunlight contains ultraviolet radiation (the component that causes a suntan) which, when absorbed by the DNA causes a cross link to form between certain adjacent bases. In most normal cases the cells can repair this damage, but unrepaired dimers of this sort cause the replicating system to skip over the mistake leaving a gap, which is supposed to be filled in later.
Unprotected exposure to UV radiation by the human skin can cause serious damage and may lead to skin cancer and extensive skin tumors.
Spontaneous mutations occur without exposure to any obvious mutagenic agent. Sometimes DNA nucleotides shift without warning to a different chemical form (know as an isomer) which in turn will form a different series of hydrogen bonds with it's partner. This leads to mistakes at the time of DNA replication.
Mutations can involve large sections of DNA becoming duplicated, usually through genetic recombination.^[7] These duplications are a major source of raw material for evolving new genes, with tens to hundreds of genes duplicated in animal genomes every million years.^[8] Most genes belong to larger families of genes of shared ancestry.^[9] Novel genes are produced by several methods, commonly through the duplication and mutation of an ancestral gene, or by recombining parts of different genes to form new combinations with new functions.^[10][11]
Here, domains act as modules, each with a particular and independent function, that can be mixed together to produce genes encoding new proteins with novel properties.^[12] For example, the human eye uses four genes to make structures that sense light: three for color vision and one for night vision; all four arose from a single ancestral gene.^[13] Another advantage of duplicating a gene (or even an entire genome) is that this increases redundancy; this allows one gene in the pair to acquire a new function while the other copy performs the original function.^[14][15] Other types of mutation occasionally create new genes from previously noncoding DNA.^[16][17]