Q26.1-2CC. - Campbell Biology

Question

Which of the trees shown here depicts an evolutionary history different from the other two? Explain.

Step-by-Step Solution

Answer

 

(a) In this given tree, it is depicted that the C and D species are the sister taxa.

(b) In this phylogenetic tree, it is shown that the C and D species are sister taxa

(c) The given tree shows that C and B are the sister taxa instead of that C and D.

 

Step 1: Phylogenetic tree analysis

Each tree has a branch point that reflects the common ancestor of different spices' branches. Sister taxa are collections of organisms that share an immediate common ancestor not shared by any other group.

Sister groups help describe the evolutionary links exhibited in a tree because the members are each other's closest relatives.

 

Step 2: Explanation of option (a)

In the (a) phylogenetic tree, C and D are the sister taxa that show a common ancestor in evolutionary history. Thus, (a) phylogenetic tree show same as (b) tree.

Step 3: Explanation of option (b)

The (b) phylogenetic tree represents that C and D are sister taxa, suggesting that they have a common ancestor that shows similar characteristics. Thus, (b) phylogenetic tree shows that C and D species are sister taxa similar to (a) tree.

Step 4: Explanation of option (c)

The evolutionary relationships in (c) exhibit a different arrangement as compared with (a) and (b) because C and B are sister taxa in the (c) diagram. At the same time, C and D are sister taxa in other (a) and (b) phylogenetic trees. Thus, C and B are different sister taxa in the (c) diagram.