The ants go marching one by one — 20 quadrillion of them

The world’s human population is predicted to exceed 8 billion in the coming months. Compared to ants, this is a minor milestone.

Researchers have made the most comprehensive assessment to date of the global population of ants — insects that have colonized nearly every part of the planet — and estimate there are 20 quadrillion of them, or about 2.5 million for every human.

Considering how common these busy and social insects are, and given the fact that they have flourished since the time of the dinosaurs, it should come as no surprise that the oldest ant fossil dates back to the Cretaceous period, about 100 million years old. Should.

“Ants certainly play a very central role in almost every terrestrial ecosystem,” said biologist Patrick Schultheis of the University of Würzburg in Germany and the University of Hong Kong, in a study published this week in the journal Proceedings of the National The co-lead author of the study is Academy of Sciences.

“They are critical to nutrient cycling, decomposition, plant seed dispersal and soil degradation. Ants are also a highly diverse group of insects, with different species performing a wide range of functions. creates key environmental players,” Schultheis said.

There are more than 12,000 known species of ants, which are usually black, brown or red in color and have three-segmented bodies. Ranging in size from about four inches (1 mm) to about 1.2 inches (3 cm), ants usually live in soil, leaf litter or decaying plants – and occasionally in human kitchens.

Ants, whose closest relatives are bees and wasps, live almost everywhere on Earth, as any picnicker knows, except for Antarctica, Greenland, Iceland and some island nations.

“I was amazed that the biomass of ants was greater than the biomass of wild mammals and birds combined, and that it reached 20 percent of human biomass. That gives you an idea of ​​the scale of their impact,” of Insects. Ecologist and study participant said. – Lead author Sabine Naughton, also of the University of Würzburg and the University of Hong Kong.

“I find the great diversity of ants fascinating. They can be small or large and show the most bizarre adaptations,” Nuten added, referring to a widespread genus of ants known as Strumigenys, which Known for long mouthparts used to hunt small invertebrates.

The researchers based their analysis on 489 studies of ant populations spanning every continent where ants live.

“Our dataset represents a large-scale collection effort of thousands of scientists. We can then extract the number of ants for different regions of the world and estimate their total global number and biomass,” Schultheis said. I succeeded,” Schultheis said.

Tropical regions have more ants than other regions, forests and drylands have more ants than urban areas.

“There are parts of the world where we have very little data and we cannot arrive at reliable estimates for all continents. Africa is one such example. We have known for a long time that this is an ant-rich continent. But it is also very little studied.” Schultheiss said.

Ants usually live in colonies, sometimes consisting of millions of them divided into groups with different roles such as workers, soldiers and queens. The workers, all female, care for the older queen and her brood, maintain the nest, and forage for food. Males mate with queens, then die.

“Some ants can certainly be very annoying, but this is a very human-centered approach,” Schultheis said.

“Most ants are actually very beneficial, even to us humans,” Schultheis added. “Think of the amount of organic matter that 20 quadrillion ants transport, remove, recycle and consume. In fact, ants are so essential to the smooth functioning of biological processes that they are called ecosystem engineers. The late ant scientist EO Wilson once called them ‘the little things that make the world run’.