You don't need to read between the lines to understand the history of interstice; its etymology is plain to see. Interstice derives from the Latin interstitium, which is itself formed from the prefix inter-, meaning "between," and -stes, meaning "standing." Interstices are the cracks and crevices of life, and the word is often used for both the literal and figurative gaps of the world. In modern uses, interstice can even refer to gaps in time or to special niches in the larger expanse of something else. Evolutionary biologist Stephen Jay Gould used it, for example, to comment, "Dinosaurs held sway for 100 million years while mammals, all the while, lived as small animals in the interstices of their world."