Sharks are incredible ocean predators that come in all shapes and sizes. Many sharks are immediately recognizable by their infamous black eyes which give them a fierce, predatory stare. But not all sharks actually have black eyes. In this article, we’ll take a close look at shark eye anatomy and find out which shark species have black eyes versus other eye colors.
Shark Eye Anatomy
Let’s start by understanding the anatomy of a shark’s eye. Sharks, like many other fish, have eyes that are specially adapted to see well underwater. The shark eye is similar to a human eye in that it has a cornea, pupil, lens, retina, and optic nerve. But there are some key differences:
- Sharks lack eyelids – their eyes are always open and the cornea is protected by a membrane.
- An area called the tapetum lucidum behind the retina reflects light back through the retina, improving vision in low light.
- A shark’s pupil can dilate widely to allow more light in.
- Special cells in the cornea allow light to pass directly to the retina.
Now let’s talk about the color of a shark’s eye. The iris, or colored part of the eye, contains pigment that determines eye color. Some sharks have a dark black/brown iris which absorbs a lot of light and makes their eyes look black. Other species have a lighter golden, green, blue or gray colored iris. The actual retina and inner parts of a shark’s eye are not pigmented, just the iris.
Sharks with Black Eyes
So which shark species typically have these signature black eyes? Here are some of the most common and well-known sharks with very dark brown or black colored irises:
| Common Name | Scientific Name |
|---|---|
| Great white shark | Carcharodon carcharias |
| Tiger shark | Galeocerdo cuvier |
| Bull shark | Carcharhinus leucas |
| Sand tiger shark | Carcharias taurus |
| Oceanic whitetip shark | Carcharhinus longimanus |
| Shortfin mako shark | Isurus oxyrinchus |
| Porbeagle shark | Lamna nasus |
| Hammerhead shark | Sphyrna sp. |
Some of the most iconic and feared sharks of the ocean like great whites, tiger sharks and bull sharks have uniformly black eyes. The black pigmentation blocks out excess light and allows them to see well when hunting prey under the surface. Oceanic whitetip sharks also have a distinctive black eye coloration.
Sharks with Non-Black Eyes
Not all sharks have black eyes. Many species have lighter golden, green, blue or gray colored irises. Here are some examples of sharks with eye colors other than black:
| Common Name | Scientific Name | Eye Color |
|---|---|---|
| Nurse shark | Ginglymostoma cirratum | Yellow/green/brown |
| Wobbegong | Orectolobus sp. | Variable colors |
| Leopard shark | Triakis semifasciata | Blue/green/gold |
| Spiny dogfish | Squalus acanthias | Green/gray/brown |
| Angel shark | Squatina sp. | Light reflective |
| Whitetip reef shark | Triaenodon obesus | Green/gold/grey |
Sharks like nurse sharks, wobbegongs, leopard sharks and spiny dogfish don’t have black eyes. Their eye coloration is lighter to help camouflage them along ocean floors and reef environments. Eye color may also vary by age and location in some species.
Purpose of Black Shark Eyes
So why have some sharks evolved dark black eye coloration while other species have lighter eyes? Here are some of the potential advantages and purposes of black “shark eyes”:
- Blocks excess sunlight – Dark pigment prevents too much light from entering the eye in bright conditions.
- Improves contrast – Absorbs diffuse light and improves visual contrast to spot prey.
- Camouflage – Blends with dark water depths where light is limited.
- Intimidation – Gives sharks a fierce, ominous appearance to scare prey.
The black eye color seems to be especially common in large, powerful sharks like great whites and tigers that feed on seals, sea lions and other large prey. Their dark eyes allow them to see well in various light conditions and also give them a terrifying look.
Conclusion
Shark eyes come in a range of colors from black to light grey, blue, green and yellow. Well-known species like the great white, tiger, and bull sharks have distinctly black eyes which give them enhanced vision and a menacing appearance. Other sharks like nurse sharks and wobbegongs have lighter eye colors that camouflage them in their environments. Dark shark eyes seem well-adapted to the predatory lifestyle of many larger open ocean sharks. So next time you see a shark with black, sinister-looking eyes, you’ll know it relies on those adaptations to survive and thrive as an apex ocean hunter.