More than 400,000 years ago, hunter-gatherers living in what is now Israel perked up a diet of game and vegetables with something unusual: tortoises.

“The evidence shows they regularly ate turtle,” said Ran Barkai, an archaeologist at Tel Aviv University and one of the researchers who made the discovery. “It was a sort of supplementary dish, maybe like a dessert or an opener to dinner.”

The findings appear in the journal Quaternary Science Reviews.

Inside the Qesem Cave near Tel Aviv, Dr. Barkai and his colleagues discovered the remains of tortoise shells with burns, as well as tortoise bones with markings left by stone tools.

The remains suggest that the inhabitants sometimes roasted tortoises whole over a fire and sometimes butchered them first, Dr. Barkai said, adding, “Somehow they cut them with stone knives, and most probably into small pieces.”