What diseases were there in the trench in World War 1? Trenche foot was very common in the trench warfare. caused from wet feet and not being able to change their socks and boots. Edit
Repels Sharks No.........human urine actually repells sharks and other fish.
Kidney. The shark has two dark-colored kidneys on either side of the midline. The shark regulates its urinary system in a way unique compared to most other vertebrates. The shark kidney extracts urea from urine and returns the urea to the blood.