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Hammerhead shark

life science Maturity 7-9 Next article →

Hammerhead sharks are a unique group of sharks in the family Sphyrnidae. They are famous for their strange, wide heads. This shape is called a cephalofoil, which looks like a T-shape or a hammer.

Hammerhead shark
Hammerhead shark

This special head helps them in many ways. It gives them better vision and helps them find food. Some species live alone, but others swim in large schools during the day. At night, they usually become solitary hunters.

The cephalofoil works like a many-purpose tool for the shark. Their eyes sit on the ends of the hammer shape. This allows them to see in a 360-degree view vertically. They can see above and below them at all times.

Hammerhead Atlantis
Hammerhead Atlantis

The wide head also acts like a large radio antenna. It holds many sensory pores called ampullae of Lorenzini. These pores detect the electric fields made by other living things. This helps the shark sweep the ocean floor for prey.

Hammerhead Shark - Marko Dimitrijevic
Hammerhead Shark - Marko Dimitrijevic

Scientists study the history of these sharks through fossils. Since sharks have soft skeletons, we mostly find their teeth. Their closest relatives are the requiem sharks.

Eusphyra blochii csiro-nfc
Eusphyra blochii csiro-nfc

Recent studies show their ancestors likely lived in the Cretaceous or Paleocene periods. Some older DNA studies thought they appeared 20 million years ago. The winghead shark is a special relative with a very large hammer. This suggests that the very first hammerheads also had large heads.

There are ten different species of hammerhead sharks in the wild. The Great Hammerhead is the largest of the group. It can grow quite big and is often very aggressive.

Great hammerhead (Duane Raver)
Great hammerhead (Duane Raver)

The smallest is the bonnethead shark, which can be 5 feet long. One large specimen caught in Florida in 1906 weighed over 1,000 pounds.

Bonnethead shark (Duane Raver)
Bonnethead shark (Duane Raver)

Most hammerheads are light gray with a greenish tint. They have white bellies to help them hide from prey below.

Smooth hammerhead (Duane Raver)
Smooth hammerhead (Duane Raver)

Hammerheads play a big role in the ocean food web. They eat fish, squid, octopus, and crustaceans. Stingrays are a favorite meal for many species.

Sphyrna media SI
Sphyrna media SI

The shark can even use its head to pin down a ray. This helps them stun the prey before eating it. Sadly, humans are a big threat to these animals. Overfishing for their fins puts many species at risk of extinction.

Hammerhead shark, Cocos Island, Costa Rica
Hammerhead shark, Cocos Island, Costa Rica
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🖼️ Images & Media (21)
File:Hammerhead shark.jpg
Hammerhead shark.jpg
Scalloped...
File:Hammerhead Atlantis.jpg
Hammerhead Atlantis.jpg
File:Hammerhead Shark - Marko Dimitrijevic.jpg
Hammerhead Shark - Marko Dimitrijevic.jpg
File:Eusphyra blochii csiro-nfc.jpg
Eusphyra blochii csiro-nfc.jpg
File:CR IUCN 3 1.svg
CR IUCN 3 1.svg
File:NE IUCN 3 1.svg
NE IUCN 3 1.svg
File:Sphyrna corona SI3.jpg
Sphyrna corona SI3.jpg
File:Carolinahmmrhd.jpg
Carolinahmmrhd.jpg
File:DD IUCN 3 1.svg
DD IUCN 3 1.svg
File:Scalloped hammerhead (Duane Raver).png
Scalloped hammerhead (Duane Raver).png
File:Sphyrna media SI.jpg
Sphyrna media SI.jpg

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