Question

Recent evidence indicates that the root of the eukaryotic tree may lie between a clade that includes unikonts and excavates, and all other eukaryotes. Draw the tree suggested by this result.

Short answer

The tree including unikonts and excavates is represented below:

Step-by-step solution

Eukaryotes

The world has a great diversity of organisms, and all are composed of cells. Depending on the structure of cells, and organisms can either be eukaryotes or prokaryotes. A eukaryote organism comprises cells that have various organelles bounded by membranous coverings and a proper nucleus.

Phylogenetic tree

Scientific study has revealed that organisms surviving today are different from extinct members, and life diversified with the changing environment. A phylogenetic tree is a way to represent the pattern in which life forms diversified and the interrelationship between different groups.

Phylogeny of eukaryotes

Eukaryotes have a separate domain, and within it, the organisms are divided into several supergroups. The advancement of research and evolutionary studies has concluded that the common ancestor (the root of the phylogenetic tree) lies between two clades.

One of the clades includes the supergroups SAR and Archaeplastida, and the other clade includes the supergroups Unikonta and Excavata. The phylogenetic tree is shown below: