The phylogeny of six species of birds is illustrated below, where the horizontal branch lengths correspond to genetic distance. These six species are distributed in three islands X, Y, and Z. Island X harbours species 1, 4, 6; Island Y harbours species 1, 2, 4; and Island Z harbours species 3, 4, 5. Which one of the following is true about the phylogenetic diversity of these islands?
To determine the phylogenetic diversity of the islands, we need to understand how genetic distance impacts diversity. Phylogenetic diversity is a measure of biodiversity that takes into account the evolutionary relationships between species. It can be visualized by examining the branch lengths in the phylogenetic tree.

Thus, comparing the phylogenetic diversity, we find the ranking as X > Y and Z > Y, confirming the correct answer.
A phylogenetic tree representing the evolutionary relationship between various vertebrates is shown below.
Given this tree topology, which one or more of the following statements is/are correct?
A phylogenetic tree for the evolution of two pigmentation traits in species of fish is shown for clades X, Y and Z. Genes A and/or B, if mutated, can cause dark pigmentation in the body.

Which one or more of the following statements is/are correct?
In the phylogenetic trees shown, the tips represent different species of geckos(labeled A to E) and the areas to which they belong. Which one of these is most consistent with the hypothesis that the geckos colonized the Western Ghats from Northeast India through the Eastern Ghats?
