Scientists estimate that there are 8.7 million species ( ~15% margin of error) on this planet. We have identified 1.3 million species so far. This includes everything from mammals and reptiles to plants and algae. However, from a human perspective, our immediate surroundings don’t seem that diverse. Especially if you live in cities. We’ve spent so much of our time and effort in creating a predictable environment and ecosystem for ourselves in our cities, with plants and animals that are beneficial to us, according to our understanding.
The earth exists in a complex system of inter-related systems that have feedback loops with each other. It is inherently difficult for humans to comprehend this complexity, This lack of comprehension, coupled with our deterministic and simplistic models of how the world works from the past have generated a lot of the world’s troubles today.
As we saw before, there are potentially 8.7 million species on this world. However, they are not spread evenly across the world. The distribution of the number of species is again dependent on complex systems of climate, geology and the evolutionary history of the planet. These patterns are referred to as “ecoregions”.
WWF (yes, that wildlife organisation with the panda logo) defines an ecoregion as a “large unit of land or water containing a geographically distinct assemblage of species, natural communities, and environmental conditions”.
The WWF has identified terrestrial, freshwater, and marine ecoregions. The terrestrial scheme divides the Earth’s land surface into 8 biogeographic realms, containing 867 smaller ecoregions. Each ecoregion is classified into one of 14 major habitat types, or biomes.
If you are trying to map these ecoregions, the boundaries get quite interesting. Like everything in nature, there is not a clean line where one ecoregion ends and other begins. An ecoregion encompasses an area within which important ecological and evolutionary processes most strongly interact and it is an approximation at the local level and at the borders.
The reason WWF categorized these ecoregions is to bring attention to the fact that unique manifestations of nature are found in temperate and boreal regions, in deserts and mountain chains as well. While it is important to protect tropical forests and coral reefs that have the most biodiversity, we shouldn’t be utilitarian in conservation efforts to maximize species conservation and ignore ecoregions that are less biodiverse, but are unique nonetheless, which are at risk of being lost forever if they are not conserved.