A study suggested that at least 5,000 years ago, Europeans included rodents in their diet. A settlement in Skara Brae, Orkney was investigated and four trenches were found with number of burnt bones of mice and voles even though there are more voles' bones found in one of the trenches, LA Times reports.

It turns out that there are actually a lot of rodents that are discovered in archeologic sites.

"Rodents are frequently excavated from older archaeological sites in Europe, but people haven't examined why they are there," said Jeremy Herman, a biologist at the National Museums of Scotland in Edinburgh. "Maybe because they are not currently a food source in Europe, no one ever thought to ask if they had been in the past."

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There are almost 60,000 small mammals bones found in Skara Brae, Orkney which is largest island in Scotland. In the 1970s, there were more than 2.5 pounds of micro mammal bones excavated from the four trenches dug near near the site. In each trench, bones are bundled together, like it was put inside a bag.

According to Herman, these bones can fill a cereal box. Voles are usually roaming the fields that is why it is strange on why people in Skara Brae have it in their houses. Interestingly, burn marks are found in the rodents, which might be possibly because they were "roasted" for food.

Despite this discovery, researchers still are unconvinced that rodents are part main source of food for people in Skara Brae. In fact, rodents might be just eaten as "snacks" judging the number of bones found. Most of the people in Skara Brae are farmers who raised cattle.

According to the study published in Royal Society Open Science, this is the first evidence of rodents being exploited by the Neolothic people. Rodents found in Skara Brae are two kinds: wood mouse and Orkney voles -- a common type of European vole.