Alex, the mathematical African Grey parrot, has died at the age of 31. Researchers at Brandeis University say they don't know the cause of death for the famous bird, who could count to 6, name 7 colors, 5 shapes and express frustration. The average life span for these birds is 50 years.
Alex was purchased at a pet shop in 1973 by scientist Irene Pepperberg, who claims that Alex had not yet reached his full cognitive potential.
Here is a very short YouTube video featuring Alex.