Ear tag ear is tagged. Australian sheep and goats are required to have visually readable ear tags printed with a Property Identification Code (PIC). They are complemented by movement documents supplied by consignors that are used for identification and tracking. Very small ear tags are available for laboratory animals such as mice and rats. They are usually sold with a device that pierces the animal's ear and installs the tag at the same time. Lab animals can also be identified by other methods such as ear punching or marking (also used for livestock; see below), implanted RFID tags (mice are too small
Viking raid warfare and tactics during a seafaring battle a Viking happened to get thrown overboard they were told to put their shield over their head to protect themselves from arrows or other shrapnel that could kill them. Sagas of the Viking Age often mention berserkers. These fabled Viking warriors are said to have spiritual magical powers from the god of war Odin that allowed them to become impervious to injuries on the battlefield. While these stories are exaggerated, the term "berserks" is rooted in truths about Viking warriors who were able to enter an intense, trance-like state whereupon they would "engage in reckless fighting."