One should also consider that the human comprehensive paradigm is based on organic biological life - There may be other forms of intelligent life in the universe that are not organic or biological - It is conceivable that some forms of intelligent beings utilized matter and the elements in an entirely different paradigm, and in fact might be more machine like in nature. These entities may evolve, if they do evolve, much differently than biological evolution. There are some alien theorists who believe the so called 'greys' are such beings and are not biologically alive in the sense humans call life.
Humans should really do a better job at attempting to understand what it means to be intelligent before assuming that they posses the quality of higher intelligence - there may be many levels and types of life and intelligence in the universe.