👉 Ichthyician, in the context of biological taxonomy and evolutionary relationships, refers to a group of animals that are closely related to other members of their respective phylum. These animals share a common ancestor with certain other species, such as fish and reptiles, but also have divergent characteristics and behaviors. The term "ichthyian" is derived from the Greek word "Ichthos," which means "fish." Ichthyians are characterized by having large, streamlined bodies that enable them to swim