Last updated on January 17, 2021
Welcome to the last post on mapping the physical environment of your fictional world. I will have more posts in the worldbuilding series when I get into fictional societies. We’ve already covered the topics of map projections, continent formation, climate, and landforms. Today, we talk about biomes.
What the Heck Is a Biome?
A biome is a community of plants and animals that give the area an environment with common characteristics. When people talk about “the environment”, biomes are what they are usually referring to. This environment gives your setting its atmosphere.
It’s a common trope to start stories in safe environments and move them to exotic locales when the story gets going. Familiar environments are perceived as safe. Exotic locales offer more danger.
Keep in mind that what is familiar to one person might not be to another. For example, to most Americans and Europeans, the civilized farmlands and cities in those temperate zones would be familiar, while the Australian outback would be exotic and dangerous. It is widely recognized that everything in Australia is trying to kill you. An Australian might disagree with this.
The exotic doesn’t need to be far away. For example, the wild forests (mostly extinct) of Europe and North America were the source of a lot of anxiety among inhabitants nearby. They were the inspiration as the source of danger in many fairy tales and fantasy stories. Think of the wolves of Little Red Riding Hood and Peter and the Wolf.
General Types of Biomes
Biomes are found in three general types: Forests, Grasslands, and Deserts. Generally, the wetter the climate, the larger the plants. Shrubs grow in all types and are the transition between each. They are usually found in drier areas.
Tree in Green Forest. Photo by Julia Volk from Pexels 
Brown Grass, Cruzilia, Brazil. Photo by fabio.tsu from Pexels 
Brown Sand Under White Clouds, Photo by Taryn Elliott from Pexels
In this article, I focus on terrestrial environments, not aquatic, except where they intersect in mangroves and marshes. If you want your setting in an aquatic environment, there are some notes at the end of this article for you to do more research.
Climate and Its Effect on Biomes
We covered climate in an earlier article, but while climate affects the natural environment and often determines what kind of flora and fauna exist in an area, they are not synonymous.
These general types of biomes turn out differently depending on the climate. For example, hot and warm climates produce tropical, subtropical, and hot desert biomes. On the other hand, cool and cold climates produce temperate, sub polar, and polar biomes.
Moisture also plays a large role in determining the biome. Generally, the wetter the climate, the larger the plants and animals. This is why we usually find forests in moist climates, though we also find dry forests in some dry climates. This is because in those areas, seasonal monsoons provide enough moisture for at least part of the year.
Moisture also plays a role in biological diversity. More arid regions have less diversity.
Also, generally, the warmer the climate, the more diverse the ecosystem, so long as the moisture levels are comparable. That is, tropical forests are more diverse than northern forests.
Worldbuilding Biomes
So how does this play out when worldbuilding and mapping biomes onto your fictional world? I used the World Wildlife Fund biome definitions and mapped biomes onto corresponding climate zones. See below or here for links to some ecoregions. These links will have detailed lists of biomes. There are other systems you can use as well.
The biomes are broad classifications of very distinct ecosystems. Certain biomes might cross different climate zones, but are generally associated with a few related climate zones. Different biomes classifications might look different depending on the climate or location. This provides opportunity for a lot of creativity for the author, depending on the atmosphere one wants in the book.
They way I went about it was to look at my climate map, figure out where forests, grasslands and deserts would go based on drier or wetter climates.
Focus on the Details
Next, I homed in on the biomes. That is, which biome would be appropriate based on the Köppen climate system? As an example, I focused on a couple of biomes and how I mapped them. This is a pretty loose application of theory to practice. There will be plenty of opportunity to drill down to specific details when you plan your actual story. Above all, you want to create a general atmosphere for your setting.
The tropical and subtropical moist broadleaf forests develop in moist tropical and subtropical climates: Af: Tropical rainforest climate, Am: Tropical monsoon climate, and Cfa: Humid subtropical.
Tropical Climates 
Tropical Moist Broadleaf Forests
The first of these climate/biome pairings, the tropical rainforest, is the classic jungle most similar to the Amazon or Congo basins. Likewise, the tropical monsoon forest is similar to Vietnam; Miami, Florida; or Yucatan, Mexico. The humid subtropical forest is similar to southern China.
Tropical and Subtropical Dry Broadleaf Forests
I’ll do one more just because I did the research and I find in an intriguing environment. The tropical and subtropical dry broadleaf forests is not what you typically think of as a tropical forest. Instead, it is seasonally wet and dry, changing as the intertropical convergence zone moves north and south. The trees in this biome are mostly deciduous.
These dry broadleaf forests develop in tropical savanna and hot semi-arid steppe climates.
Tropical Savanna and Semi-Arid Steppe Climates 
Tropical Dry Broadleaf Forests
As an example of a dry broadleaf forest in a tropical savannah climate, look to Thailand, Cambodia or Tamil Nadu in India. Additionally, you would find a dry forest in a semi-arid steppe in the Gran Chaco of Paraguay or the Deccan Plateau of India. For some reason, I am intrigued by the India-like environment. I think a fantasy story set in a mythical India-like world would be a fascinating read.
Flora and Fauna
Once you have these biomes mapped to climate, you can decide what actually lives there. Figure out what kind of plants and animals live in the area. What are the main identifying flora and fauna? You don’t need an exhaustive list, just the main ones that give the right feel for the environment.
When deciding on flora and fauna, use real-world examples to mimic your fantasy world. For areas you want to actually as a fantasy setting, you’ll want more detail. Research some of the ecoregions the World Wildlife Fund uses to define the environments of the various biomes.
For example, in the Mediterranean forests, woodlands, and scrub, the typical flora is oak and pine trees. The typical fauna is the small mammal: badgers, small cats, mongoose, and mice. The Mediterranean biome is also home to larger animals such as gazelles, sheep and goats, and wild dogs like the jackal and hyena. Wild boars are common in Italy and Spain. Don’t forget birds such as vultures and eagles.
Fantasy Plants and Animals
If you are worldbuilding a fantastical world, you might want fantastical flora and fauna. You can create new plants and animals that we see in the real world but are adapted to a different environment. Animals adapt an move around. Climates change. Polar bears became brown bears when the ice retreated.
Maybe a bear the size of a cat or mouse could evolve in the desert. Maybe fast-running flocks of lizards similar to dinosaurs evolve in grasslands. Don’t get too carried away. Mushrooms require a lot of moisture so you wouldn’t see large masses of them year-round in the desert, though you might see them after a rare rainstorm.
Put as much detail into the areas you want to use in your stories. Focus on the areas that you want to use as a setting. It helps to have an idea of what other options are there in case your characters travel to a different part of your world. Feel free to use real-world examples as a short-cut.
Remember though, that fantasy is all about the non-mundane, so the fantastical elements of your world might be these environments. To do it properly, take the biome and create something new. That is, invent a new plant or animal that would fit in the environment. It might take some real research into biology and environmental science.
If you do decide to create a fantastical biome, make it part of the story. That is, there should be a story reason for the difference from the real world. Exotic fantasy animals for the sake of making something up often feels forced. However, if there is a story reason for the change, it makes the story much richer and likely you will come up with something original.
Monsters
The next step in worldbuilding your biomes is to populate them with monsters. What kinds of monsters live in that environment?
Werewolves and werebears might be common in temperate forests, while giant lizards or snakes might be common in jungles. You might find fire-breathing creatures in deserts, but not likely in polar regions. Don’t put a colony of giant frogs in a desert unless there is a localized source of water. Even then, the colony would not be large.
Next, think about what creatures are sentient. For instance, are humans the only sentient creatures or have others become sentient? Think about lizardfolk in tropical forest biomes or Rakshasas in the tropical dry forest (for an India-like setting). Centaurs might develop sentience in the grasslands and steppes.
You could also leave off the exotic monsters and use the most dangerous monster of all: humans. Have humans evolved into multiple species? Think of the elves and orcs of Tolkien. For those that want to avoid that cliché, you can create other types of sub-species adapted to particular environments.
Once we know what sentient creatures live in what areas, we can start to focus on how their societies are organized. That will be a complex set of topics covered in the next set of articles in the worldbuilding series.
Resources for Further Research
Find Wikipedia’s Outline of Biomes here.
