A few years ago, one of the great figures of contemporary biology, Ernst Mayr, published some reflections on the likelihood of success in the search for extraterrestrial intelligence. He considered the prospects very low. His reasoning had to do with the adaptive value of what we call "higher intelligence," meaning the particular human form of intellectual organization. Mayr estimated the number of species since the origin of life at about fifty billion, only one of which "achieved the kind of intelligence needed to establish a civilization." It did so very recently, perhaps 100,000 years ago. It is generally assumed that only one small breeding group survived, of which we are all descendants.
Mayr speculated that the human form of intellectual organization may not be favored by selection. The history of life on Earth, he wrote, refutes the claim that "it is better to be smart than to be stupid," at least judging by biological success: beetles and bacteria, for example, are vastly more successful than humans in terms of survival. He also made the rather somber observation that "the average life expectancy of a species is about 100,000 years."
We are entering a period of human history that may provide an answer to the question of whether it is better to be smart than stupid. The most hopeful prospect is that the question will not be answered: if it receives a definite answer, that answer can only be that humans were a kind of "biological error," using their allotted 100,000 years to destroy themselves and, in the process, much else.
The species has surely developed the capacity to do just that, and a hypothetical extraterrestrial observer might well conclude that humans have demonstrated that capacity throughout their history, dramatically in the past few hundred years, with an assault on the environment that sustains life, on the diversity of more complex organisms, and with cold and calculated savagery, on each other as well.
