Submission + - Whales survive only after huge sharks died out (theregister.co.uk)
The mega-shark was no lightweight. At 110 tonnes, it was about 30 times as heavy as a Great White and is thought to have had the most powerful bite of any animal in the Earth's history. With those humongous size sharks, whales don't get any fighting chance
It was such a ravenous predator, that its extinction may have allowed whales — today's heftiest seagoing fatties — to grow to the sizes we see nowadays. “When we calculated the time of Megalodon’s extinction, we noticed that the modern function and gigantic sizes of filter feeder whales became established around that time. Future research will investigate if Megalodon’s extinction played a part in the evolution of these new classes of whales,” said Catalina Pimiento of the University of Florida