In a world where sharks have evolved with some appendage roughly equivalent to opposable thumbs, this adaptation gave them the capability to create technology, and thereby to dominate the seas to such an extent that the bony fish never came into their own, and so eventually humans never evolved either. The sharks developed their technology in a progression roughly parallel to our own technological evolution. All of their major cities are along the coastline, and although most of them prefer to swim in the ocean, they have devised inventions to allow them to live on the land or in fresh water, and some individuals prefer these ecosystems. Their species developed cyborg type augmentation earlier than we did, so while the current shark toy may be sporting jet engines equivalent to our 1950’s era designs, it has them surgically anchored to its artificially reinforced skeletal system, and has the controls hardwired into its nervous system.