“Of the four billion life forms which have existed on this planet, three billion, nine hundred and sixty million are now extinct. We don't know why. Some by wanton extinction, some through natural catastrophe, some destroyed by meteorites and asteroids. In the light of these mass extinctions it really does seem unreasonable to suppose that Homo sapiens should be exempt. Our species will have been one of the shortest-lived of all, a mere blink, you may say, in the eye of time.”

“Life has had to deal with environmental change, especially climate change, since the beginning of its existence on Earth. Species adjust or go extinct, and both have happened. For life-forms with our kinds of cells—eukaryotic, the kind with distinct organelles—the average existence of a species is about 1 million years, and, on average, one species goes extinct a year, at least of the species we have named and know, including those we know only from fossil records."-Dan Botkin, excerpt from THE MOON IN THE NAUTILUS SHELL.”

“Global warming, along with the cutting and burning of forests and other critical habitats, is causing the loss of living species at a level comparable to the extinction event that wiped out the dinosaurs 65 million years ago. That event was believed to have been caused by a giant asteroid. This time it is not an asteroid colliding with the Earth and wreaking havoc: it is us.”

“For the entire course of evolution leading from our primitive mammalian forebears of a hundred million years ago to the single lineage that threaded its way to become the first Homo sapiens, the total number of individuals it required might have been one hundred billion. Unknowingly, they all lived and died for us. (21)”

“If humans one day become extinct from a catastrophic collision, there would be no greater tragedy in the history of life in the universe. Not because we lacked the brain power to protect ourselves but because we lacked the foresight. The dominant species that replaces us in post-apocalyptic Earth just might wonder, as they gaze upon our mounted skeletons in their natural history museums, why large-headed Homo sapiens fared no better than the proverbially pea-brained dinosaurs.”

“You know, at times like this one feels, well, perhaps extinct animals should be left extinct.”