Baleen Whale Shark

Baleen whale sharks are a group of whale shark descendants that had diversified into many different varieties of filter-feeding sharks. They range in many different shapes and sizes, with some being about the size of a Commerson's dolphin, Atlantic baleen dolphin sharks (Delphinocacharius atlanticus), to one of the biggest species, the pacific baleen whale sharks (Megatichthysus cetasus), being the biggest species of fish ever and the biggest shark known in existence, much bigger than even the biggest of Megalodon (a gigantic prehistoric great white shark-like carnivorous shark), growing up to about 120 feet long and weighing about 115 tons, being slightly bigger than the extinct blue whale, making it the biggest ever animal on Earth. Fortunately, all species of baleen whale sharks are gentle filter-feeders, feeding on nothing but plankton, krill, crustacean larvae, and small fish.

Evolution
In the Late Holocene, man killed off (almost) all baleen whale species due to their selfish and greedy nature, but eventually, man has succumbed to extinction. Fortunately, whale sharks have survived due to humans who successfully protected whale sharks from the brink of extinction from human fishermen and poachers. After the extinction of many baleen whales (but not all baleen whales), whale sharks start to diversify into many different shapes and sizes, with some evolving into parasitic blood-sucking vampire sharks to the gentle giant baleen whale sharks. Despite competition with surviving baleen whales such as humpback whales and such, baleen whale sharks flourish.