In subsequent citations, only use the first author's last name followed by et al. in the signal phrase or in parentheses. (Kernis et al., 1993). In et al. , et should not be followed by a period.
Transcript of Hammerhead Shark Eyes. Structure of Eye. The structure of a hammerhead sharks eye is very similar to the human eye, they have a cornea, lens, retina, pupil and iris. Their retina has both cone and rod cells, which means they can see light, dark, and colours.
Interesting Hammerhead shark Facts: 1  Size of the hammerhead shark depends on the species. They can reach 3 to 20 feet in length and up to 1000 pounds in weight. 2  Hammerhead sharks have white bellies and olive green or grey-brownish back. 3  Mouth of hammerhead sharks is located on the underside of the head.