They tackled a vertiginous question, of the style that one can dare to ask oneself when one is a child but which has a real scientific interest: how many ants are there on Earth? Some are entomologists, others naturalists, but in total they are six, all researchers at the Hong Kong University of Sciences, to have co-directed this work, professors Schulteiss, Noten, Wang, Wong, Brassard and Guénard. Their results have just been published in Processings of the National Academy of Science, the journal of the United States Academy of Sciences. Verdict: there are 20 million billion ants on Earth. A number with fifteen zeros, and impossible to imagine.
The researchers are the first to have been surprised by this gigantic figure since the previous estimate had only proposed a range between 1 and 10 million billion. But in ten years, the studies have multiplied, the techniques of statistical calculation have been perfected and they have been able to rely on 489 studies of ant populations, coming from all the continents where there are colonies, it is i.e. everywhere except Antarctica and Greenland.
The figure being disconcerting, the study offers comparisons to help measure what it represents. We learn, for example, that for one human being, there are 2.5 million ants, or that the total weight of ants, their biomass, exceeds that of birds and wild mammals combined.
A weight which obviously has an impact, which the researchers describe amply in their study: the ants, they say, forge the world, they recycle, aerate, modify the organic matter, the humus, the earth, not to mention that their activity is useful to others, butterflies, birds, plants… all without polluting their environment. The study notes, however, that despite their number, ant populations are declining due to the destruction of their habitats, climate change and their more or less rapid adaptation to the arrival of invasive species in their territories.