These sharks got their name because of the unusual shape of their head.
Keeping warm when you are out and about in cold weather is simple - trap in warmth by wearing layers like coats, gloves and hats.
But what about in the animal kingdom where bobble hats are hard to come by?
Well, scientists have discovered that hammerhead sharks adopt a very clever technique for maintaining their body temperature when hunting for food in very cold waters.
They hold their breath!
Why might that help? It's all to do with their gills, where a lot of their body heat escapes.
In the deepest parts of the ocean, the water temperature drops considerably. Some areas, it is as cold as five degrees Celsius, which can be dangerous for cold-blooded creatures like sharks.
If their bodies drop in temperature too much, their eyesight and brain function can be impaired. Their muscles can also stop working, meaning they are no longer to keep swimming, which can be fatal.
But researchers studying scalloped hammerhead sharks have observed them travelling down to waters over 20 degrees colder than they are used to closer to the surface.