Great white sharks are a lot hungrier than scientists realized, a new study suggests. The old line of thinking, based on research done in the 1980s, is that a great white could snack on, say, a 60-pound seal pup and go six weeks without another meal. As it turns out, it’s more like two weeks, max, say researchers at the University of Tasmania, reports AFP. In fact, the sharks are likely to be feeding every few days, not every few weeks. The findings are based on a meticulous study of a dozen sharks that factored in their metabolic rate and swim speeds. So why was the old study so far off? The best guess is that “they picked a shark that probably wasn’t working very hard at the time when they did it,” one of the new researchers tells Australia’s ABC News.