Carl Sagan's Response to Mayr
I would have to agree with al lot of what Sagan said. Mostly in this crucial paragraph,
"But the basic argument is, I think, acceptable to all of us. Evolution is opportunistic and not foresighted. It does not "plan" to develop intelligent life a few billion years into the future. It responds to short-term contingencies. And yet, other things being equal, it is better to be smart than to be stupid, and an overall trend toward intelligence can be perceived in the fossil record. On some worlds, the selection pressure for intelligence may be higher; on others, lower.
The Planetary Society: SETI Page