Creating Species

A story needs characters to be engaging. When considering sci-fi and fantasy (and to a lesser extent literary fiction) these characters can take any form imaginable, from humans to anthropomorphized animals to imagined species and sentient wind. With speculative fiction, the form a character takes is limited only by the author's imagination.

This post will focus on the development of the physical aspects of species in science fiction and fantasy. For guidance on creating new cultures, see Creating Cultures.

Note: When developing new species, be careful to avoid embedding harmful stereotypes. Just because the creations are fictional doesn't mean they can't cause real world harm if they reflect real world bias. Do your research, especially if you are drawing inspiration from a group or culture outside of your own, and listen to beta readers and editors who raise these concerns. When in doubt, make changes to avoid harmful stereotypes. Hiring a sensitivity reader is also a good idea whenever you are working with characters/cultures that are outside your personal experience or identity.

Appearance

Appearance is where most authors will start when creating a new species. This is how the species looks—the external features. The possibilities are endless, but start with the basics:

1. Do they have a physical form or are they a form of energy or insubstantial?

2. Are they humanoid or similar to an existing plant or animal in appearance? Or are they completely alien?

   
   

Once you have decided on the basics, consider the following:

1. How is the body divided? Are there multiple sections (like with mammals) or are they one continuous mass (like a worm)?

   • If the species has more than one body part, what are they and what are their functions? Does every part have a function or are they vestigial or decorative?

2. Does the species have a face? If yes, how does it differ from faces as we understand them? Where is the face located?

3. How many limbs do they have? Are all the limbs the same (like a spider's) or are there different types (like humans)?

4. How big is the species? Are they large, like whales or elephants, or small like mice or ants?

5. What colour(s) are they? Does colouration vary within the species or is it consistent across individuals?

   
   

It is also important to consider variations in the appearance of a species. Do all the members look the same? If there is variation, what kind? Do they differ in colour, size, shape or build? Are there variations possible in all aspects of their appearance or just some? For example, does the number of arms change, but not the number of legs? Are these variations genetic or are they based on lifestyles or habits? Are these variations something the individual has done to them such as tattoos or piercings? Is this variation a personal choice or standard practice within the culture? Are these variations arbitrary (like eye colour) or do they signal something about the individual, such as sex, race, sexuality or function?

Depending on the scope of the narrative and how prominent the species is in it, it might also be important to know how the species ages. Does their appearance change based on their stage in life like a tadpole turning into a frog? Or is the change more subtle, like in humans with wrinkles and greying hair?

Physiology

Physiology is how the body of a species functions. The first step is figuring out how similar this species is to an existing one. If using an existing species as a template, focus on how the new species deviates from the existing species. If working from scratch, focus on a few key elements of the species's physiology that make them distinctive. Unless you are writing hardcore science fiction, it is unlikely you will need to develop the physiology as in-depth as other aspects, as these elements are less likely to end up on the page.

The following are the most important aspects of physiology to consider as they have direct impacts on the development of characters:

1. Do they breathe? If so, what/how do they breathe?

2. How do they take in energy and eliminate waste? Do they eat or absorb their energy through their skin or some other organ? What kind of waste product(s) does the species produce? Is this waste useful to others, like plants using carbon dioxide breathed out by humans and humans breathing in oxygen eliminated by plants?

3. Is there another substance or item they require for their body to function? Can they change their abilities/function through the use of outside agents?

4. What kinds of organs do they have and where are they located in the body? How important are these organs? Are they completely necessary, like a human brain or something they can live without, like an appendix? If there are multiples of an organ, like human kidneys, are both necessary? What happens when one is no longer functional?

Reproduction

Many narratives won't need to dive into the details of how a species reproduces, but it's worth having a basic idea since reproduction is the driving force for all living things. As a result, it can have a huge impact on how a culture is built, its customs and its rituals. An asexually reproducing species will conduct itself very differently from a sexually reproducing species. Consider what biological sexes the species has? Male and female, like humans? Do they have additional biological sexes like the ooloi in Octavia Butler's Xenogenesis series? Does this additional sex play a part in reproduction or does it serve some other function? Does the species lack biological sex as we think of it or have completely different sexes?

Note: Sex and gender are separate concepts. Sex refers to the reproductive organs of an individual and any secondary sexual characteristics. The basis of sex is biological. The basis of gender is cultural and informs the general behaviour and presentation (clothing, makeup, hair, etc. ) of an individual. Sex and gender can exist independently of each other, or a society can be built on the assumption that they are aligned.

Movement

This is one of the most fun aspects of developing a new species: how they move.

The type of movement a species is capable of will depend on their bodies, both what kinds of limbs/appendages they have as well as their physiology. When considering movement, start with the basics: How do they most commonly move from point A to point B?

Once that is established, ask are they capable of other forms of movement? What are all the ways they can use their bodies to move through space? Do they walk on their limbs? Float/hover? Does it depend on the situation? Are there certain types of movement that can only be done in certain circumstances or that require a great deal of energy or training to achieve? Do all genders/races/designations of the species move in the same way?

Moving beyond the more mundane parts of movement, are they capable of movement that it's impossible in our physical world, like teleportation or walking through solid objects? Are these abilities connected to the physics of the world, the species' physiology or magic?

How does the species interact with the world around them to create movement? Can they use air currents to fly, walk up walls or swing between tree branches? How much of this is based on the physiology/biology of the species and how much is based on the physics of the world?

And finally, what does the movement look like? Is it smooth and effortless? Jerky? Wobbly? Fast or slow? Strong? Uncertain? Does the appearance of the limbs change as they move through space or do they remain the same? How much variation between individuals is there in the quality of the moments? Does everyone have a distinctive walk or is it more uniform across the species? Does a specific quality of movement designate a certain kind of training or genetics, like how trained dancers move differently than the general population?

Communication

There are many ways to communicate. While spoken or written language is what most people commonly think about, symbols, gestures, structure and tone all play a role in communication. When creating a new species, you want to focus on the basics of communication first:

1. Do they have language as we understand it? If yes, is it spoken, gestural or pictorial? If it's spoken, do they use mouths for speech like humans do or is there some other way they produce sound?

   • If the species "speak" but don't have mouths, what part of their physiology is involved in the speech?

2. If the species doesn't have language as we understand it, how is their communication informed by their physiology? Do they communicate with sounds, scent, gestures, movements, touch, taste or colouration?

   • Using existing plants and animals as inspiration is a great place to start.

For guidance on building language systems and slang, see Creating Language Systems.

Abilities

The abilities of a species are directly linked to all other aspects of creature building. The ability of a species to fly, for example, is tied to their appearance and/or physiology. When working in fantasy, this covers magical abilities, but isn't limited to them. (See the Magical Creature's post for more on building a magical species.) Can this species produce venom? Can they blend in with their surroundings? Can their singing induce sleep? Can they lift massive amounts of weight? Do they have indestructible stomachs and can eat anything? Can they grow back a severed limb?

This is the aspect of species development that is the most flexible. Especially when operating in speculative fiction, there are absolutely no limits to what a species can do. Focus on what abilities are important narratively. The Xenogenesis series is a perfect example of this. The Oankali's ability to breed with other species is integral to the themes and narratives of the three books. Without their specific form of reproduction, there is no story.

Not every ability of a new species needs to be integral to the narrative. It could be simpler, like a species of firefly that burns so brightly, the planet is never dark. Or a venomous creature that serves as an obstacle to the protagonist when they accidentally step on it in the forest. Just make sure that the abilities are serving the story world and not just because.

Conclusion

The above is a starting point for developing a new species. It will not always be necessary to develop every aspect, especially if they are closely related to an already existing species or only play a minor role in the narrative. Some elements might have no bearing on the narrative and not make it onto the page. In these cases, it isn't strictly necessary to develop species in-depth, but doing so will give you more information to draw on as you write. Even if the details don't make it into the narrative, readers can tell when the work has been done as it comes through in little ways to create a fully realized world.