18:16 10 December 2015
The fossils at the Smithsonian's National Museum of Natural History were incorrectly labeled as bones of extinct walrus instead of a sperm whale. The researchers then decided to take another look.
Initially, they were faced with problems as the bone weighed around 300 pounds and was thoroughly encased in rock.
"This specimen is huge and the first time we rolled it over to see the underside, it took four people and we sacrificed a couple of fingers," says Nick Pyenson, the curator of fossil marine mammals and research co-author. "Having that 3D model was crucial."
"The discovery was pretty late on in the process and we had already written most of the manuscript," says Boersma. "We were looking at the computer model and talking over the phone and Nick said, 'I think it has upper teeth'.
"We had to re-evaluate our paper which was exciting and stressful at the same time because it opened up our research to new possibilities and was the moment we realised that this whale was different to anything else in the fossil records."
"I definitely think this whale is pretty fierce and ate its fair share of marine mammals. But when we think about Moby Dick and hear stories about sperm whales ferociously attacking humans - that's not actually something we see in the wild," the scientist says.
"Even killer whales that have been known to attack and kill humans in captivity - to my knowledge, there's no record of them attacking humans in the wild."