Fifty million years after humanity's extinction, the world has once more grown wild. In the forests of North America, the deer-like descendants of rabbits flee attacks by large predatory rats. Giant antelope and striding baboons more reminiscent of dinosaurs roam Africa's savannas.

This is the tangled new jungle of life Dougal Dixon's book After Man presents to readers. Originally published in 1981 and re-released in a lightly-revised edition in May, After Man is the foundational entry in the field of "speculative zoology," where writers and artists play with ideas about what kind of world evolution might produce if humanity were to disappear. The book is a fully illustrated bestiary of future animals, complete with field sketches, detailed paintings and thorough explorations of their ecology. In the pollution-ridden 1980s, it offered both an arresting vision of the future and a glimmer of hope.

Image: Breakdown Press

In the years since then, concerns over climate change and ecological collapse have grown, forcing people to imagine a world that isn't just polluted, but where things like sea level rise and extreme weather are reshaping entire landscapes. Even more so today than in the 1980s, humanity's impact on the Earth raises the question of what sorts of animals are going to be able to survive—or even thrive—in the future.

"After Man was essentially the first grand, large-scale speculative project that involved numerous species—a whole world of species, literally," Darren Naish, a vertebrate paleontologist with a longstanding interest in speculative zoology told Earther.

Science fiction authors have used evolutionary ideas to imagine new creatures since at least 1895, when H.G Wells' The Time Machine introduced readers to future iterations of humanity like the subterranean Morlocks and docile Eloi. Early 20th century writer Edgar Rice Burroughs' prodigious pulp output often included entire fictional faunas, which he places in places like Mars or in underground jungles.

Image: Breakdown Press

With After Man, Dixon wanted to do something different. An artist and writer who'd studied paleontology in university, he'd been toying for a while with the question of what a post-mass extinction world might look like, something that would allow him to present how natural selection actually works. The process of building that future world involved taking a fairly close look at the one we're currently living in, Dixon said.

First, he chose to set it far enough in the future that humanity and its direct impacts would have been erased. The ghost of a long-ago human-induced collapse haunts the text, though: there are no domesticated animals, no megafauna like tigers or rhinos, no descendants of today's endangered species. Dixon looked at the period 50 million years in the past and tried to project that level of change onto the animals he had left.

Some of his creatures aren't that changed from their forebears—a tree-climbing beaver, a leaf-mimicking toad. Others, including stilt-legged, crocodile-snouted fishing mammals and enormous seabirds that swim through the oceans in place of whales, are completely bizarre.

"Most of my speculative work involves giving fictitious examples of factual processes," Dixon told Earther. "The forces of adaptive radiation, convergence and all the rest [of the evolutionary processes] would work on whatever animals we are talking about."

The result is that some of Dixon's weirder creations arguably have a basis in reality. "Some of Dougal's ideas seem prophetic and reasonable in view of more recently acquired knowledge," Naish said. Consider his most famous creation, the Deathstalker: a giant predatory bat, whose wings have been converted to legs and whose back legs are now clawed hands. While the idea of a flightless bat might seem preposterous, the short-tailed bats of New Zealand and Central American vampire bats are extremely at home on the ground, able to scurry quickly with their wings folded up to protect them. In the absence of competitors, it's not unreasonable to suggest that bats might recolonize the ground given enough time.

"After Man was essentially the first grand, large-scale speculative project that involved numerous species—a whole world of species, literally."

The basic premise that humanity is likely to take much of the planet's ecology with us when we go is in accord with current thinking about the effects of climate change and a sixth mass extinction, which a growing number of researchers believe we are in the early stages of. Nonetheless, the book has some gaps. Fish, insects, and coral ecosystems largely don't appear, despite recent research showing how overfishing and rising temperatures are leading to dramatic die-offs and biodiversity losses among these groups. Dixon keeps plants in the background as a familiar stage for his creatures, and the introduction—which establishes some principles of past evolution—has become somewhat dated.

Image: Breakdown Press

In the revised edition, Dixon says, the introduction has been rewritten and expanded to cover advances in paleontology and geology. As for changing the book itself to take climate change into effect, Dixon doesn't think it's necessary: the book is set far enough in the future that the world has moved on.

After Man's greatest impact was in launching speculative zoology as a genre. Following the book's success, Dixon wrote The New Dinosaurs (a somewhat dated glimpse at how the world might have looked if the dinosaurs hadn't gone extinct) and Man After Man, an exploration of genetically engineered species of humans. Throughout the 90s and mid-2000s, several authors took a stab at the subject, including paleontologist Peter Ward and fiction writers like Kurt Vonnegut and Stephen Baxter. In 2002, Dixon and several other scientists collaborated on The Future is Wild, a documentary miniseries and companion book. Websites like the defunct Speculative Dinosaur Project and Serina: A Natural History of the World of Birds—as well as Naish's own Squamazoic—often carried a clear influence from Dixon's work.

Image: Breakdown Press

Part of the fun of speculative zoology, Naish says, is that it gives people a chance to spin out different scenarios of evolution and imagine weird creatures. What would it take to get from a baboon to a something like a mammalian Tyrannosaurus, or from a seabird to a whale? Playing with speculative zoology encourages a kind of double vision: a recognition that every organism around us has immense potential waiting in its genetic code, waiting to be unlocked.

Speculative zoology can also offer some catharsis for those of us engrossed in the current planetary crisis. As Earth's five previous mass extinctions have shown, evolution has always gone into overdrive after cataclysms. Humanity may not be around in 50 million years, but life probably will.

Asher Elbein is a journalist and short fiction writer from Austin. His website is and you can find him on Twitter @asher_elbein.