Birds and How They Digest Foods

Evolution has played a major role in the way the animals developed. And it is especially apparent when you look at the thousands of different species of animals across the globe, and see the many different ways that they have evolved to eat and process foods to sustain their bodies. And the bird is no different.

The digestive system of birds is different from humans and most mammals in a number of ways. For one, birds do not have teeth. This poses a problem for them when it comes to digesting their food. Teeth serve the useful purpose of breaking up the food into smaller particles so that the body can digest them more easily. But, without teeth, how can this be done?

As the bird species evolved throughout millions of years, they managed to come up with their own unique resolution. Instead of breaking up the foods in their mouth, they break it up in their stomachs. In order to do this, the stomach is broken up into two sections, called chambers.

This can be seen by taking the example of a bird consuming a seed. The bird does not chew the seed. It swallows the seed whole. The seed first falls down into the front chamber. This chamber has many chemicals and digestive juices. Their function is to chemically process the food to help break it down. It works much like the saliva does in human mouths. The food is liberally coated with these digestive juices until it is well mixed.

Following that, the food is passed on to chamber number two. This is the chamber that processes the food physically. This is analogous to the way we physically process the foods in our mouth by chewing.

In practice, the process is relatively simple. The seeds and all of the other foods that the bird has eaten have already been softened up by the digestive juices from the first chamber. Thus the second chamber has a much easier time with the food since it is already partially pre-digested. The bird is able to contract and relax the second chamber walls so that they grind up the food mixture between them.

Besides this, however, the bird has an additional trick up its sleeve. And that trick is grit. Grit is simply a collection of rough granules of sand or stone – and it is an essential element in a bird’s digestion process. To help it to digest food in the second chamber, the bird eats grit. As the walls of the chamber open and close to smash into each other, the grit that the bird has swallowed helps it to break up the food much better than if the food was the only thing present.

Grit is so effective because food is susceptible to being broken up a lot easier when it is being smashed by rough pebbles or grit than it can with just smashing against itself. And this is why you will often see birds eating stones or sand. It’s not for nourishment. It’s to help them digest food.