Reindeer have 4 stomachs, what is the name of the fourth stomach?

Reindeer are herbivorous mammals that are native to Alaska, Canada, Greenland, northern Europe, and northern Asia.

They are characterized by their grey-brown fur and antlers. In many areas reindeer are used a source of food, milk, and transportation for people. However, brown bears, polar bears, and wolves often prey on reindeer. Combined with over-hunting, reindeer populations are under threat and they are classed as a vulnerable species.

Reindeer, like all other members of the deer family, are ruminants. Ruminants have four stomachs and “chew the cud”. This means that they first chew their food enough to swallow it so it can be stored in the first stomach (the rumen). It is then broken down further in the second stomach (the reticulum) before they burp up food from this stomach back into their mouth to be chewed further. This is often done while they are resting and is called chewing the cud. Once swallowed again, the food goes into the third stomach (the omasum) where water is absorbed. Finally, it is sent to the abomasum to be further broken down before it is sent to the intestines where nutrients are absorbed into the body.