The simplest known organism which is capable of independent existence includes about 100 different genes. For each of 100 different specific genes to be formed spontaneously (in 10 billion years) the probability is 2 raised to the power of -100 raised to the power of 100 (or one chance in 10 followed by 3,000 zeroes). For them to be formed at the same time, and in close proximity, the probability is much lower.”
- Michael Hart, "Atmospheric Evolution, the Drake Equation and DNA: Sparse Life in an Infinite Universe" Extraterrestrials – Where Are They? (Cambridge University Press, 1995 pp. 222-223)
Oh wait, let me check my notes.
For other extraterrestrial life stories, go here.
