Question

1) Why do species 1, 2, and 3 are in the middle of the Kasaki cluster?

2) What is the relationship with Kasaki nozomi sp. (above), Kasaki sp. (below), Kasaki mizore sp. and so on

3) Are species 1-3 new species?

-42 Yoshikawa natsuki sp. 16S rRNA -51 Yoshikawa yuuko sp. 16S rRNA 26 Kasaki nozomi sp. 16S rRNA 80 species 1 78 species 2 79 species 3 - 19 Kasaki sp. AUS isolate 16S rRNA -54 Kasaki mizore sp. 16S rRNA 41 Kasaki yoroizuka sp. 16S rRNA 56 Kasaki yamane sp. 16S rRNA 9 Kasaki taka sp. 16S rRNA

Answer 1

ANSWER 1 :-

1. There is no specific reason citing the presence of the three species in the middle of the phylogenetic tree. This depends mainly upon the divergence event which leads to its placing in the middle of the tree although the analysis of the characters or traits is essential in determining the relevant answer.
2. It can be seen that the Kasaki sp. tends to show a common internal node indicating its recent common ancestor from which it has diverged. The species mentioned in the query has a recent common ancestry which has diverged from the common ancestor of all the Kasaki sp.

ANSWER 2 :-

1. ​​​​​​​Kasaki nazomi sp. is basically considered as an ingroup to all the other species mentioned in the query mainly due to all these species having a recent common ancestor as compared to the outgroup which does not share any common ancestor with the species.
2. The association is represented in terms of the groups being paraphyletic groups.

ANSWER 3 :-

1. The branch length basically indicates the number of changes that have occurred in total during the process of divergence from the ancestral species.
2. In the above mentioned phylogeny, the branch length and the node representing divergence does not indicate species 1, 2 and 3 to have diverged recently but in the entire group composed of Kasaki sp., it is the Kasaki taka species that have recently diverged taking into consideration it has accumulated less changes.
3. Hence the three mentioned species are not recent evolved species.