The Same Intron Was Sequenced from Five Different Taxa (Taxa

question 109

Multiple Choice

The same intron was sequenced from five different taxa (taxa A-E) whose evolutionary relationships are disputed. The data matrix given shows six variable sites (1-6, left column) in the DNA sequences obtained from each of the five species. Taxon A serves as the outgroup for this analysis. $\begin{array}{|c|c|c|c|c|c|}\hline & \operatorname{taxon} \mathrm{A} & \operatorname{tax} n \mathrm{~B} & \operatorname{tax} n \mathrm{C} & \operatorname{taxon} \mathrm{D} & \operatorname{taxon} \mathrm{E} \\\hline 1 & \mathrm{~A} & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{G} \\\hline 2 & \mathrm{C} & \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\\hline 3 & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{A} \\\hline 4 & \mathrm{~A} & \mathrm{~A} & \mathrm{~T} & \mathrm{~A} & \mathrm{~T} \\\hline 5 & \mathrm{~A} & \mathrm{C} & \mathrm{A} & \mathrm{C} & \mathrm{C} \\\hline 6 & \mathrm{~A} & \mathrm{~A} & \mathrm{C} & \mathrm{A} & \mathrm{C} \\\hline\end{array}$ Which of the phylogenies below explains the relatedness between these taxa with the FEWEST evolutionary steps?

• A)phylogeny I
• B)phylogeny II
• C)Both phylogenetic trees have the same number of evolutionary steps.

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Definitions:

Sample Mean Difference

The difference between the means of two samples, used in hypothesis testing and estimation.

Normally Distributed

Describes data that follows a normal curve or distribution, where most observations cluster around the central mean.

Protraction

The movement forward of a body part, such as the jaw or shoulder blade, away from the spine.

Transverse Plane

An anatomical plane that divides the body into upper and lower parts, also known as the horizontal plane.