The terrible irony is that we may bring back dinosaurs after all. Not by the purposeful and adept application of our intelligence to some technological end, as we'd like to imagine it, but rather by complete, inept accident. Through our neglectful treatment of the environment via the emission of—yes, fossil fuels—the viscous matter of dinosaurs, as the common lore goes, might very well bring the reptiles back into existence, as if the powerful spirits of these extinct creatures are guiding us to warm the planet for their return. Sixty-five million years hence, some future species might contemplate the mysterious fate of Homo sapiens as they look at the reconstructed human skeletons displayed in their museums. Why did they go extinct?, they'll wonder. Was it a comet? Severe drought? A flood? It's safe to say that the name we proudly gave ourselves—"wise ape"—will not be among the choices considered by whatever future gravedigging taxonomist broods over our poor descendant's skull, alas!
This is something that came to mind while reading J.G. Ballard's 1962 novel, The Drowned World. In some future time, much of the Earth's landmass is covered in water, the top few stories of the tallest skyscrapers providing shelter for a group of surveyors making their way through London. The plants loom large in the carbon rich environment, the atmosphere is oppressively hot and humid, and iguanas, alligators and crocodiles likewise thrive in this new Triassic. (Dinosaurs of some sort have even been seen further north.) The main character, Kerans, begins to feel his mind slipping, as it has slipped in others close to him, into a world of dreams. Except that it isn't a dream, really, but images from a long suppressed tribal memory, a time when such an environment wasn't so foreign.
"All the way down the creek, perched in the windows of the office blocks and department stores, the iguanas watched them go past, their hard frozen heads jerking stiffly. They launched themselves into the wake of the cutter, snapping at the insects dislodged from the air-weed and rotting logs, then swam through the windows and clambered up the staircases to their former vantage-points, piled three deep across each other. Without the reptiles, the lagoons and the creeks of office blocks half-submerged in the immense heat would have had a strange dream-like beauty, but the iguanas and basilisks brought the fantasy down to earth. As their seats in the one-time boardrooms indicated, the reptiles had taken over the city. Once again they were the dominant form of life.
"Looking up at the ancient impassive faces, Kerans could understand the curious fear they roused, re-kindling archaic memories of the terrifying jungles of the Paleocene, when the reptiles had gone down before the emergent mammals, and sense the implacable hatred one zoological class feels towards another that usurps it."