What is a vertebrate?

Question 1

what makes vertebrates different from other chordates?

Answer 1

• Bony skeleton
  (Osteoblasts, Osteoclasts, Osteocytes)
• More complex sense organs of head
• More complex brain

Question 2

What are the tree main evolutionary lineages of vertebrates and basal lineages?

Answer 2

Chodrichthyans (cartilagenous)

Actinopterygians
(ray-finned)

Sarcopterygians
(lobe-finned)

Lampreys
(basal)

Hagfish
(basal)