The figure shows a hypothesis for the evolution of visual opsins in tetrapods. At the tips, each triangle represents a particular visual pigment found in a modern tetrapod. Along ancestral branches, the hypothesized evolutionary history of these opsins are shown. Which of the following is true of this evolutionary hypothesis?
A) Squamate reptiles and birds have maintained the ancestral opsins.
B) Humans have lost a single opsin relative to the tetrapod ancestor.
C) New world primates lost two opsins, but then gained a new one.
D) Opsins have been gained and lost in every tetrapod lineage.

Question

The figure shows a hypothesis for the evolution of visual opsins in tetrapods. At the tips, each triangle represents a particular visual pigment found in a modern tetrapod. Along ancestral branches, the hypothesized evolutionary history of these opsins are shown. Which of the following is true of this evolutionary hypothesis? 
A) Squamate reptiles and birds have maintained the ancestral opsins. 
B) Humans have lost a single opsin relative to the tetrapod ancestor. 
C) New world primates lost two opsins, but then gained a new one. 
D) Opsins have been gained and lost in every tetrapod lineage.

Quizplus · Accepted Answer

The Answer of The figure shows a hypothesis for the evolution of visual opsins in tetrapods. At the tips, each triangle represents a particular visual pigment found in a modern tetrapod. Along ancestral branches, the hypothesized evolutionary history of these opsins are shown. Which of the following is true of this evolutionary hypothesis? 
A) Squamate reptiles and birds have maintained the ancestral opsins. 
B) Humans have lost a single opsin relative to the tetrapod ancestor. 
C) New world primates lost two opsins, but then gained a new one. 
D) Opsins have been gained and lost in every tetrapod lineage.

The Figure Shows a Hypothesis for the Evolution of Visual