Everyone knows songbirds and parrots. If a bird can speak words and sentences, at first glance, it seems to be very smart. Actually, it is not true. The ability to reproduce human speech does not indicate bird’s high level intelligence.

According to scientists, the most intelligent bird is the common black crow.  That's why they came to this conclusion:

1. Crows also have the ability to understand the movement of water. In a test-tube study, researchers placed a treat in a test tube of water out of the crows' reach. The crows then added stones to the water until the treat became available.

2. Crows are capable of remembering faces and holding grudges. Not only do they remember, they also pass that knowledge along to other members of their community 

3. Crows can use tools to get food. For example, they may use sticks to get food out from narrow holes or crevices.

4. Empathy can be shown by crows. Researchers say that crows are able to empathize with other crows who are suffering illness or stress.

5. Crows behave may vary depending on who is watching them. For example, if crows know they are being watched by their brethren, they may hide food or use tools more carefully.

6. Crows are known to hold funeral-like gatherings when one of their own dies. This is believed to occur for learning purposes. The crows are thought to communicate the cause of death to inform others of the dangers or perhaps discuss the communal hierarchy.

7. Crows are able to prioritize. Based on test results, the scientists found out that if the birds know that they will receive more benefits, they are ready to wait.