Are flatworms, roundworms and arthropods a clade? A) Yes B) No
Answer (1)
The question is asking whether flatworms, roundworms, and arthropods form a clade. A clade, in biological terms, is a group of organisms that consists of a common ancestor and all its lineal descendants, representing a single branch on the 'tree of life.'
Flatworms belong to the phylum Platyhelminthes. They are relatively simple bilaterians and are considered among the most primitive of the bilaterally symmetrical animals.
Roundworms are part of the phylum Nematoda. They are also bilaterians but are more complex than flatworms, with a complete digestive system.
Arthropods make up the phylum Arthropoda and include insects, arachnids, and crustaceans. They are highly complex bilaterians with segmented bodies and exoskeletons.
Given this information, flatworms, roundworms, and arthropods do not share a recent common ancestor exclusive to only these groups. They belong to different phyla and are part of separate evolutionary branches.
Therefore, the answer is B) No , they are not a clade because they do not all derive from a single, unique common ancestor. Instead, they represent separate evolutionary paths among the bilaterians.
