Which of these structures would most likely have been observed in the common ancestor of chondrichthyans and osteichthyans?
A) a mineralized, bony skeleton
B) opercula
C) a spiral valve intestine
D) a swim bladder

Question

Quizplus · Accepted Answer

A mineralized, bony skeleton is a feature that would most likely have been observed in the common ancestor of chondrichthyans (cartilaginous fishes) and osteichthyans (bony fishes), as both groups show evidence of mineralized tissues in their lineage.

Which of These Structures Would Most Likely Have Been Observed