Evolutionarily,the Jaws of Vertebrates Developed From

Question

Evolutionarily,the jaws of vertebrates developed from
A)the circular mouth of lampreys.
B)the last gill arch of jawless fishes.
C)the third and fourth gill arches of jawless fishes.
D)the operculum.
E)the claspers.

Accepted Answer

According to current understanding, the jaws of vertebrates (including humans) evolved from the skeletal supports of the third and fourth gill arches of jawless fishes. These skeletal supports became modified and incorporated into the head, eventually developing into the movable, muscular jaws that we see in modern jawed vertebrates. This evolutionary innovation provided many advantages, including the ability to grasp and manipulate prey, leading to the diversification and success of jawed vertebrates. The circular mouth of lampreys and the operculum and claspers are not directly related to the evolution of jaws.