I always thought they couldn’t get cancer.
A tumor on the lower jaw of a great white shark, near the Neptune Islands, South Australia. It’s the first documented tumor in this species. Image: Andrew Fox and Sam Cahir
Scientists have known for more than 150 years that sharks get cancer. And yet the belief persists that the animals don’t suffer from the disease.
That misconception is promoted in part by those who sell shark cartilage, who claim that the substance will help cure cancer, said David Shiffman, a shark researcher and doctoral student at the University of Miami. But no studies have shown that shark cartilage is an effective treatment, and the demand for the material has helped decimate shark populations, researchers say: Humans kill about 100 million sharks per year, according to a March 2013 study (although many factors contribute to the killing of sharks, including demand for shark-fin soup).