Livyatan, as you can see here, closely resembled the modern sperm whale. The difference lies – apart from its massively muscular body – in its large jaw with sharp teeth in both jaws (the modern sperm whale only has small teeth in its lower jaw). The modern sperm whale is the last surviving member of the family. About five million years ago, the once mighty sperm whales went extinct as baleen whales became faster swimmers and the first dolphins emerged. Because dolphins were so intelligent, the “dull-witted” sperm whales were outcompeted. Livyatan also disappeared. The species that survives today escaped extinction by diving into the deep oceans and hunting squid. The modern sperm whale continues this behavior and does not need large, sharp teeth for it.