Which of the following best describes the phylogenetic position of the single-celled eukaryotic organisms?
A)They form a monophyletic phylum,the Protozoa,within the kingdom AmmaliA.
B)They form a monophyletic kingdom,the Protista,separate from the kingdom Animalia.
C)They form a monophyletic group within the Monera.
D)They do not form a valid monophyletic taxon at any level of the Linnaean hierarchy.

Question

Quizplus · Accepted Answer

Single-celled eukaryotic organisms do not form a valid monophyletic taxon at any level of the Linnaean hierarchy because they are distributed across multiple branches of the eukaryotic tree, including various protists, fungi, animals, and plants. This diversity means they do not share a single common ancestor that was itself a single-celled eukaryote to the exclusion of all other types of organisms.

Which of the Following Best Describes the Phylogenetic Position of the Single-Celled