Identify the statement(s) about mammals that is/are not true: 

P. All mammals have a skull.

Q. All mammals have three ear bones: the incus, malleus, and stapes. 

R. Mammals are jawless.

Read the following statements about deuterostomes carefully, and then identify which ones are correct.  

P. In deuterostomes, the blastopore develops into an anus.  

Q. Deuterostomes are triploblastic.  

R. Deuterostomes have radial symmetry.  

S. Deuterostomes are pseudocoelemates.

The vertebral column and cranium are found in:

The figure below shows the phylogeny of amniotes.

Identify the incorrect statement about the phylogeny of amniotes:

Which of the following is one of the features of Tiktaalik that made it an intermediate model between terrestrial and aquatic forms?