Iman Ghosh in Nautilus:
Our planet supports approximately 8.7 million species, of which over a quarter live in water. But humans can have a hard time comprehending numbers this big, so it can be difficult to really appreciate the breadth of this incredible diversity of life on Earth. To fully grasp this scale, we draw from research from “The biomass distribution on Earth,” by Yinon M. Bar-On, Rob Phillips, and Ron Milo to break down the total composition of the living world, in terms of its biomass, and where we fit into this picture.
A “carbon-based life form” might sound like something out of science fiction, but that’s what we and all other living things are. Carbon is used in complex molecules and compounds—making it an essential part of our biology. That’s why biomass, or the mass of organisms, is typically measured in terms of carbon makeup. In our visualization, one cube represents 1 million metric tons of carbon, and every thousand of these cubes is equal to 1 Gigaton (Gt C). Here’s how the numbers stack up in terms of biomass of life on Earth:
Plants make up the overwhelming majority of biomass on Earth. There are 320,000 species of plants, and their vital photosynthetic processes keep entire ecosystems from falling apart. Fungi is the third most abundant type of life—and although 148,000 species of fungi have been identified by scientists, it’s estimated there may be millions more.