Nature is often depicted as being brutal, where only the strongest survive, and fantasy novels often follow this idea. But, predator versus prey is not the only way animals interact with one another in the real world. While different species living in the same area often compete with one another for resources, there are many examples of co-operation as well, often called symbiosis.

One familiar example of this is our relationship with dogs. Our ancestors benefited from the wolf’s keen senses and hunting abilities, and we provided food and safety. Over time this partnership developed into dogs being one of the most successful species on the planet. In speculative fiction, examples of symbiosis can often be found in science fiction.

In the Star Trek universe, there is an entire species based on this idea—the symbiont Dax is passed from host to host through history, retaining the memories of each. The symbiont gets a home, the host benefits from the collective experiences of those that came before them. The Babel fish from The Hitchhiker’s Guide to the Galaxy feeds on brain wave energy, and in return translates all languages for its host.

But examples of symbiosis in fantasy are not as plentiful, though when it is weaved into the genre it usually creates a very interesting story. Symbiosis usually involves communities of different animals, and many of the traditional fantasy creatures range from rare to the stereotypical “last of its kind”. Symbiosis also implies a relationship that has evolved over time, and is an idea that works well both with creating a new fantasy creature or inspiring a creative tweak to the classics.

When two different species interact in a way that is beneficial to both, it’s called mutualism. Most examples of mutualism involve an exchange of protection for sustenance. James Gurney’s Dinotopia incorporates this sort of symbiosis into fantasy literature. The story is about a utopia where humans and dinosaurs co-exist and create a civilization together. This symbiotic relationship forms the basis for the entire plot of the story.

There are many real-world examples of mutualistic behavior that could form the starting point of a fantastical creature. Ants are often found in mutualistic relationships with various plants, might the same hold true for a group of sentient, humanoid plants? Would the quality of their ants be a status symbol, or might they take them for granted, just another part of life?

What if only one species is benefitting from the interaction, while the other is harmed? This is parasitism, and is most often associated with bugs and microscopic organisms such as fleas and worms. The parasite in science fiction is well known, for example, the “face hugger” from the Alien series. The character Doro from Wild Seed by Octavia Butler also has a parasitic, body-jumping ability, allowing him to move from host to host.

Sometimes, though very rarely, only one species benefits from the interaction while the other is unharmed. This is called commensalism (science has a fancy name for everything). For example, the clown fish lives amongst the sea anemone, whose venom keeps away predators that would eat the clown fish. The fish had to evolve a special immunity from this venom, and it doesn’t hurt the anemone at all. The Doctor Who episode “The Beast Below” weaves this form of symbiosis into the plot and setting of the story. The Earth is gone, and the British Empire is being carried through space on the back of a space whale. I don’t want to give away any more of the episode, but a relationship that starts off parasitic turns into commensalism.

While mutualism can drive world and character building, parasitism probably lends itself more to plots, though incorporating any of these can make a more robust fantasy story. In real life the host can’t really hold a conversation with their symbiont, but there is no such limitation in fantasy. One of my favorite symbiotic relationships in fantasy is that of D and Left Hand from the Vampire Hunter D series. D is host to a symbiotic organism in his left hand, which offers him advice and helps him survive his rather dangerous job. Left Hand’s brash, jovial personality also contrasts with D’s stoicism, and he gives the reader/viewer a look into D’s thoughts and motives. It’s a good example of using the idea of symbiosis to create character and plot.

Title image by LynxGriffin.