A new species of aquatic chordate is discovered that closely resembles an ancient form. It has the following characteristics: external armour of bony plates, no paired lateral fins, and a suspension- feeding mode of nutrition. In addition to these, it will probably have which of the following characteristics?

Question

Quizplus · Accepted Answer

The description of the external armour of bony plates and suspension-feeding mode of nutrition suggest that this species likely belongs to the group of jawless fish known as Agnatha, which includes extinct forms such as the ostracoderms. Therefore, it would not have jaws (choice A). It would also not have an amniotic egg (choice B), legs (choice C), endothermy (choice D), or a forebrain (choice E) as these are all features found in more derived groups of chordates such as reptiles, mammals, and birds.

A New Species of Aquatic Chordate Is Discovered That Closely