In 2008 , researchers uncovered what they believe is the world 's oldest known full-body impression of a primitive flying insect , a 300 million-year-old specimen from the Carboniferous period . In 2008 , researchers at Tufts University uncovered what they believe is the world 's oldest known full-body impression of a primitive flying insect , a 300 million-year-old specimen from the Carboniferous Period .