Imagine that a mutation occurred in an individual belonging to a lineage on a ph
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Question
Imagine that a mutation occurred in an individual belonging to a lineage on a phylogenetic tree, and that this mutation changed some visible aspect of the organism that carried it. For example, suppose that the organism was a flowering plant, and that the mutation changed the plant's flower color allele so that the plant's blossoms were yellow rather than white. This mutant allele has the potential to either be lost from the population or to increase in frequency over many generations (Figure 1). The latter case is more likely when the mutant allele allows its carriers to produce greater numbers of offspring-in other words, the allele is more I con fixation of the mutant all requency when it s higher fitn than the an I allele. In this cas on will fav No matter whether fixation of the derived allele occurs as a result of selection or as a result of genetic drift, this fixation corresponds to extinction of the ancestral allele Moreover, with the loss of the ancestral allele, the population will have evolved at the phenotypic level-specifically, the population that was formerly fixed for the possession of white flowers will now be made up of only yellow-flowered individuals. Because the time it takes for a mutant allele to arise and become fixed is generally very short compared to the time between successive lineage-splitting events, it is usually safe to ignore the brief period when both the derived and ancestral alleles coexisted in the population, and to instead imagine that the derived trait arose in an evolutionary instant on some internal branch of the phylogenetic tree (Figure 2) Figure 1 Figure Detail Trait evolution is not predictable. However, once a lineage becomes fixed for a derived trait, descendants of that lineage wll all have the derived trait unless there is a subsequent evolutionary change to a new trait (which might even resemble the original ancestral trait). Thus, assuming there is not a subsequent change in flower color, all lineages descended from the original population that was fixed for yellow flowers will also have yellow flowers Of course, as phylogenetic trees branch, different lineages accumulate different traits. Figure 3 illustrates this idea using a clade that You can see that the differe species are the result of changes that occurred after the group began to diversify. In fact, if you were told which traits evolved on which branches, you could precisely predict which traits each living species would have Conversely, if given the features of each living species you could explain the variation between the species by Yelow YellowYel Yellow White WhiteWhite rd species 9909e Os s among these four Yellow fixed Yellow voking just four events of trait evolution As this example illustrates, descendants of an ancestral lineage tend to share common traits, and the presence of these character topology of phylogeneti Figure 2: State change and trait fixation When a trait branches of a phyloge change of branch color the branch, the eve represent both the original occurrence of the allowS to infer the Although phyloge own to te on the ce is a rich and complex field based on the ee, whether with a shown) or a mark on simple idea that as long as traits (or charact SO (compared to the rate o sua ineage branching), then the distribution of t mong s provides evidence of how recently these species ion shared a common ancestor O 2008 Nature Education All rights One profound implication of this way of thinking about rait ev ing species are the ummation of their evolutionary history. In other words t all the traits of a living spe you can assume that eacht arose on ou somewhere in that species' history. While some traits, such as the presence of a distinct cellular nu evolved in the ancient past and are shared by many organisms, others, like spoken language, arose much more recently (in this case, very recently, as speech is a uniquely human trait). Thus, understanding the evolutionary history o arose. Moreover, phylogen biological diversity an ra to understanding where on the tree of life these species' dis rees serve as extremely powerful too amou r organizing this knowledge oExplanation / Answer
As per above informtion,
Mutation occurred in an individual belonging to a lineage on a phylogenetic tree, and that this mutation changed some visible aspect of oragansim that carried it.
with example of Plant mutation, In plant mutation occur in flower color allele.
In this mutation results show yellow blossoms rathern that white.
This mutation allele has potetial to either lost or increase frequency over many generations.
when the allele is more likely to increase in frequecy when it confers higher fitness that the ancestral allele.
In this case, Natural selection will favor fixation of mutant allele.