An exam in ornithology class. An ornithology class is about to take an exam. Every student is sitted in their chair, then, the teacher proceeds to give all a single bird claw to every student. - **Teacher**: Ok, I want you, with those meres claws, to identify when was born, when did it die and what bird species was alive. A student rises his hand: - **Student**: But how the actual hell can we know that with only a crap of claw?! - **Teacher**: So, Are you telling me you can not? - **Student**: Of f*cking course not! - **Teacher**: Ok, please, give me your name and your birth date. The student take off one of his shoes, and put his foot over the table. - **Student**: Guess it.