Why does the Vatican not consider beavers, muskrats, or capybara as meat on Fridays?

So in the 17th century, the Bishop of Quebec approached his superiors in the Church and asked whether his flock would be permitted to eat beaver meat on Fridays during Lent, despite the fact that meat-eating was forbidden. Since the semi-aquatic rodent was a skilled swimmer, the Church declared that the beaver was a fish. Being a fish, beaver barbeques were permitted throughout Lent. Problem solved!

The Church, by the way, also classified another semi-aquatic rodent, the capybara, as a fish for dietary purposes. The critter, the largest rodent in the world, is commonly eaten during Lent in Venezuela. "It's delicious," one restaurant owner told the New York Sun in 2005. "I know it's a rat, but it tastes really good."