TIL Pigeons use Earth's magnetic field to navigate. A small spot on their beak contains magnetite which acts as a tiny GPS unit for the homing pigeon by giving it information about its position relative to Earth's poles.

https://ssec.si.edu/stemvisions-blog/how-do-birds-navigate#:~:text=Researchers%20have%20discovered%20a%20small,position%20relative%20to%20Earth's%20poles.

https://www.reddit.com/r/todayilearned/comments/15lizjv/til_pigeons_use_earths_magnetic_field_to_navigate/