Now, however, scientists came to the conclusion that whales are hunted on large prey.
Now palaeontologists from the Museums Victoria and Monash University went for the recreation of the teeth of the whales to find out what they actually are and successes in re-developing the digital teeth models from the fossilised baleen whales using the 3D Scanners.
All living whales are descended from terrestrial mammals, but how these aquatic creatures evolved into giant filter-feeders remains a biological mystery.
"We found that ancient whales had sharp teeth similar to lions and dingoes so it likely they used their teeth to kill rather than filter", Evans said. Researchers for the experiment employed the fossils of Baleen whale and the modern mammals, gathered from specimen collections across the world.
Erich Fitzgerald, Museums Victoria's senior curator of vertebrate palaeontology, said, "These results are the first to show that ancient baleen whales had extremely sharp teeth with one function - cutting the flesh of their prey".
But until now, researchers weren't exactly sure how ancient whales put their teeth to use.
Australian scientists have published a new study which disputes Charles Darwin's theory of evolution for whales and argues they were once top tier predators.
Their growth spurt, which has seen blue whales balloon to up to 30m in legnth, was mainly driven by climate changes and a massive increase in the amount of plankton in the ocean. The whale teeth are found to be much more like the wedging blades of the big, wild cat and dog's teeth. "By contrast, species that use their teeth as a sieve have blunt teeth with rounded edges that help to filter prey from water".
Worldwide research involving Monash biologists has provided new insights into how the feeding habits of the whale - the biggest animal - have evolved.
For decades many scientists have believed that the ancestors of the giant blue whale and humpback whale developed zig-zag shaped teeth, like those of leopard seals, that enabled them to suck in and trap food in their mouth while seawater flowed back out.