If there were only 100 animals on Earth...

For this video, we based ourselves on a scientific study published in the journal PNAS in 2018. The study estimates the total biomass on Earth, meaning the mass of life on Earth, as well as the distribution of this mass according to different groups of species (plants, animals, fungi…). The masses of the different groups were estimated from their carbon mass.
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We first focused on animals. We calculated the percentage of each group based on their total mass. For greater readability, these percentages were rounded to the nearest unit (except when the data justified a precise value). We also decided to present these percentage as the number of individuals (out of a total of 100 animals of equal mass).

Finally, we calculated the distribution of total biomass by adding non-animal groups such as plants or bacteria.