The world has 20 quadrillion ants, which weigh more than all wild mammals and birds combined.

You're not alone if you've been curious about the global ant population.

According to a new estimate by scientists from Germany's Julius Maximilian University in Würzburg, there are 20 quadrillion ants worldwide.

Before this, scientists could only make "basically informed approximations" about their population size. So, they compiled information from 489 studies that measured ant populations in different locations. The results were then extended to account for the globe's size, which led to the final tally of 20 quadrillions.

Reasons why ants matter:

Although ants are common in tropical and subtropical locations, their abundance varies greatly depending on local conditions. Engineers may impress scientists, but scientists need to know how many there are to understand their impact on ecosystems.

There are about 15,700 kinds of ants, and they all play essential roles in ecosystems, from seed dispersal to nutrient cycling and sustenance. Researchers at Julius Maximilian University saw the lack of reliable data in this area and set out to fill the void.

Their 489 investigations included ant populations from every continent and the world's major biomes and ecosystems. They estimate 3 1015 ground-dwelling ants worldwide. Twenty quadrillions are more plausible.

But that's not the total cost estimate:

The population's overall biomass is predicted to be around 12 megatons. According to New Scientist's calculations, this is far more than the nine megatons of biomass accounted for by all wild birds and mammals. In comparison, human biomass is 60 megatons or 60 times more significant.

The study also discovered that ground-foraging ants were more common in arid locations, while forest ants were more concentrated in forest areas. However, we can't get a complete picture from the estimates. For instance, the estimations don't account for ants that live underground or in trees; they only consider those that are visible on the ground.

Dr. Patrick Schultheiss of the University of Florida told New Scientist that there was also a lack of information regarding ant populations in Africa and north Asia. This means that there are still significant knowledge gaps about ant populations.

Since ants play an essential part in many ecosystems, it is helpful to get a rough idea of how many there are. This implies researchers may apply the same approaches in identical places to determine what shifted in ant biomass and its impacts.

Research results were released this week in PNAS.

Abstract:

Understanding organisms' relevance in ecosystems and their ecological roles requires knowledge of their distribution and abundance. Bugs, long considered the "tiny things that control the world," today lack such understanding. However, there is currently neither a credible estimate of the total number of insects on Earth nor the abundance of specific insects in different biomes or habitats. This is true even for insects as common as ants, who are of immense ecological relevance. To get a realistic picture of the ant population worldwide, we aggregated ground-dwelling and tree-dwelling species information. All main biomes and habitats are represented in our meta-analysis of 489 studies. The overall number of ants on Earth is probably around 201015, and we estimate that there are more than 31015 ground-dwelling ants. This second number is equivalent to biomass of about 12 megatons of dry carbon. This is almost the same as 20% of the human body, and it's more than the total biomass of all wild birds and mammals. The diversity and abundance of ground-dwelling ants vary significantly between habitats but are most dense in tropical and subtropical climates. The quantity of ants that live in leaf litter is most significant in forests, while the abundance of ground-foraging ants is most incredible in deserts. These findings not only highlight the importance of ants to terrestrial ecosystems but also reveal significant information gaps in ecological and geographical contexts. Our results establish a vital foundation for future research into the factors influencing abundance patterns and monitoring insects' reactions to environmental shifts.