This leads to precipitation (rain) :)
It is necessary to match the donor's and the recipient's blood before a transfusion because the immune system will react badly if blood cells are not compatible. The immune system is responsible for patrolling or for guarding the circulation in the body. Without its proper function, the body will be exposed into different types of infections.
When blood goes through the process of transfusion, the cells are treated the same way as infections or foreign invaders. When they are not compatible with the recipient the immune system will be massively activated which can cause immediate clotting systems in the blood. The results of this clotting can lead to shock, kidney failure, collapse of the circulatory system, and worst death.
An eagle is at the top of the food chain. A mountain isn't considered food. Maybe the plants it carries and algae, but the mountain itself is not a food. Mice as we should know is well know to be (depending on the food chain and how many animals you add,) is either close to the bottom or pushing just a taste towards the middle.
