Science tells us that Earth has had five mass species’ extinction events in its history. Writer Elizabeth Kolbert, in her Pulitzer-prize winning book, “The Sixth Extinction: An Unnatural History,” argues persuasively that we experiencing a sixth extinction right now, one caused by man, and not by volcano or asteroid. Shawn Sheehy, in his haunting “Beyond the Sixth Extinction: A Post-Apocalyptic Pop-Up,” speculates on the dire circumstances of vast and irreversible climate change and suggests how some species may adapt, hybridize and succeed in the future. Our guest writer, Colette Fu, is an award-winning Philadelphia-based artist, whose pop-up books are owned by many museums and collections. Colette writes a cogent review of the cautiously optimistic book.