Unfortunately, no, all I know about it is that it causes extreme damage.
If the bill is counterfeit and the paper is wood-based, the iodine in the pen solution will react with the starch and leave a dark brown or black mark.
The only trait that I know that those birds and a squirrel have in common in that they both love birdseed.
The "medium" is the substance or material that carries a mechanical wave. One of the most important things to remember about waves is that they transport energy, not matter. This makes them different from other phenomenon in physics.
For simple definitions, visit the following website:
https://www.ducksters.com/science/physics/waves.php