Researchers Document Nine "Remarkable" Abilities Sharks Have Developed Over 450 Million Years

A new BBC feature has catalogued nine surprising traits sharks have evolved, challenging common perceptions of the ancient predators.

• Scientists at Macquarie University in Sydney observed that Port Jackson sharks can be trained to surface at specific tank levels when music is played, showing a preference for jazz over classical.
• Research has found that bamboo sharks can distinguish between quantities, such as three versus five objects, and remember geometric shapes for approximately one year.
• Shark embryos of the sand tiger species engage in intrauterine cannibalism, with up to five embryos per uterus competing until only one survives in each.
• Some shark species, including bull and hammerhead sharks, nourish their developing young through umbilical cords in the womb, similar to human gestation.