Uncover the mystery of hammerhead sharks

A marine biology study shows, the strange structure of hammerhead sharks is a transcendent feature that allows them to observe with wide viewing angles of up to 360 degrees.

Previously, researchers argued a lot about the hammerhead of this fish that is making it difficult or convenient for their sight.

Specifically, in 1948, zoologist Gordon Walls, the visionary leader of vertebrate species, proposed the eye position of hammerhead sharks that limited its eyesight.

But in 1984, the leading shark expert Leonard Campagno countered with the hypothesis that the distance between the hammerhead's shark eyes made it possible to see with two eyes accurately.

The secret curtain of hammerhead shark has been opened.Research shows a strange head that makes hammerhead sharks look better published in Experimental Biology.

Currently, this mystery has been solved. The study of Dr. Michelle McComb, Florida Atlantic University, Florida, USA and colleagues pointed out, the hammer-shaped head helps this fish to see two eyes at the same time and can look 360 degrees.

They have put many different shark species into a large fish tank. Then, they placed sensors on the skin of sharks to measure the level of activity of the brain. Specifically, they check whether these types of objects react to beams of light from different locations around the tank. Doing so will measure the range of sharks' vision.

Researchers also discovered that the hammer head has many benefits. By swimming sideways to one side the hammerhead shark can observe behind it.

Moreover, the position of the eye allows this fish to see 360 ​​degrees of vertical plane, which means it can be seen both at the top and bottom at all times. 'As well as developing the ability to hunt, this is the advantage of small sharks in front of large predatory sharks' Dr. McComb said.

Dr. McComb said: 'This study has confirmed that hammerhead sharks are able to see both eyes forward. This means they can go straight ahead and appreciate the distance, especially for any prey they hunt for. '

The binocular vision appears when the area of ​​the eyes coincides, allowing animals to accurately understand the depth and distance, important characteristics for hunting species.

The study of Dr. McComb's team also showed that the degree of overlap between visual areas of the eyes will increase with the width of the head.

Lemon sharks (Negaprion brevirostris) have a 10-degree eye each eye. Scalloped hammerhead (Sphyrna lewini) has a relatively broader head, and the interwoven vision of the eyes is 32 degrees. However, the winghead shark (Eusphyra blochii) has a binocular vision of 48 degrees because its head is almost half the length of the body. 'Because the hammerhead shark head is enlarged, its level of vision is broader,' explains Dr. McComb.

The results were surprising to researchers. Dr. McComb confessed: 'I believed that hammerhead sharks could not be able to see with two eyes because of their eyes on both sides of the head. However, the position of the eyes is the key to opening. The eyes of hammerhead sharks slightly forward, which allows the eyesight area of ​​each eye to overlap significantly '.

McComb also said: 'This study confirms that eyesight plays a big role in the evolution of the most exotic inhabitants of the ocean. This is a question that existed 200 years ago when hammerhead sharks were discovered. '