(WHTM) — As people across the country prepare their holiday meals, here’s some food for thought: Why are turkeys associated with Thanksgiving?

According to Britannica, many people believe that the pilgrims ate turkey during the very first Thanksgiving in 1621. But there is no real proof that turkey was served. The only bird mentioned by the pilgrims during that time was the “wild fowl.”

Fowl could mean turkeys, geese, or ducks were served on the first Thanksgiving. Turkeys may have been served, but the Old Farmer’s Almanac states that back in that time, turkey was not a typical food.

By the turn of the 19th century, turkey had become a popular protein on holidays. Britannica said there are a few reasons why.

One reason is that turkeys were common, with roughly 10 million being in America at the time of European contact. Another reason is that a turkey can feed a family.

Ashley Rose Young, a historian at the Smithsonian’s National Museum of American History, previously told CNBC that migration from England also factors into the bird’s popularity here in the U.S. She said eating turkey became a Thanksgiving tradition through a century-long process of regional New England foods being “consumed during traditional harvest festivals” and “making their way through the United States.”

The Old Farmer’s Almanac stated that an editor named Sarah Josepha Hale campaigned for Thanksgiving to be a national holiday, and wrote about making it a holiday to many presidents.

In 1863, President Lincoln made the holiday a national holiday, and turkeys started to be on dinner plates around the country. Because of this, Hale is considered to be the “godmother of Thanksgiving.”

A fun tradition regarding Thanksgiving deals with U.S. presidents pardoning turkeys. Since 1947, a “National Thanksgiving Turkey” has been presented to the president. During an official ceremony, the president “pardons” the turkey, meaning its life is spared and it does not get eaten.