When the first embryo in each uterus reaches a certain size it consumes all its siblings. Sources: Radio 4 Natural Histories, BBC One Shark, Planet Earth and In Living Memory.

While being towed, she gave birth to five live pups and one stillborn, all measuring between 4.5 and 6.5 feet: as large as a full-grown whitetip reef shark. During the 20th century, basking sharks ...

Between eight and 14 feet but can reach up to 23 feet Using this method, scientists discovered Greenland sharks have a life expectancy of at least 272 years and could reach 392, give or take about ...

While cartilaginous fish like sharks and rays are known to use sound for communicating, tracking prey, and for safely moving underwater, they are not known for producing sounds voluntarily.

It’s estimated that its jaw would span 2.7 by 3.4 metres wide. That’s easily big enough to swallow two adult people side-by-side, or a London taxi cab. These jaws were lined with 276 teeth, and ...