Intelligence would tend to be an evolutionary imperative

Q1: What is convergent evolution? How does this idea suggest that intelligence would tend to be an evolutionary imperative? Q2: Briefly explain the idea of the "encephalization quotient" (EQ). How does the value of this quotient for humans suggest that we as a species are exceptionally intelligent? What does the EQ tell us about intelligence among other animal species? Q3: What are the three general categories of signals that might be detected at great distance? What are the current prospects for detecting each type of signal through SETI efforts?