• Virtually unchanged in the past 90 million years 
  • first true “modern” sharks
  • They quickly became a dominant force in the oceans worldwide and continue to live today 
  • These sharks developed a wide variety of teeth and replaced them at rate which was previously unparalleled
  • What made them “modern”... 
  • Vetebral centra calcified 
  • More flexible fins
  • Reduced spines
  • ***Ventrally positioned mouth***
  • Maneuverable upper jaw resulting in stronger and larger bites (Fenton and Fenton)
Dried skull and spine of a modern blue shark
showing calcified vertebrate (1963)
Specimen courtesy Canadian Museum of Nature
Cat # 75 - 1963