Monday May 1, 2017
Book 17: A Little Immortality — Part I

NOTE: The use of the word "After" in the first panel suggests an immediate causality which would have been of great credit to Earth's sophonts had things actually gone down that way. In 1980 CE a multi-disciplinary team led by physicist Luis Alvarez identified meteoric impact as the source of the iridium at the K-T boundary in Earth's fossil record, but it took several decades for Earthlings to get around to properly sweeping up the sorts of things that could lay down funereal iridium in the future. 

Fortunately for the deoxyribonucleic acid family of sapient, self-replicating molecular megastructures, they got around to it in time.