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.
Hammerhead shark, (family Sphyrnidae), any of eight shark species belonging to the genera Sphyrna (with seven species) and Eusphyrna (with one species), which are characterized by a flattened hammer- or shovel-shaped head, or cephalofoil.