Ants combat global warming, scientist claims

They may only be tiny, and live for just three months, but ants could be the key to solving climate change.

Rough harvester ants have been found to ‘weather’ minerals in sand to produce calcium carbonate, also known as limestone.

When the ants make this limestone, the process traps carbon dioxide in the rock, ultimately removing it from the atmosphere.

It is unsure how the minerals are converted, however, and theories range from ants licking the sand, to excreting the substance.

The discovery was made by Professor Ronald Dorn from the University of Arizona Tempe.

Professor Dorn buried sand at six sites in the Catalina Mountains in Arizona, and Palo Duro Canyon in Texas, 25 years ago.

Every five years, he measured how much the minerals olivine and plagioclase degraded in the sand, and discovered the ants break down minerals up to 300 times faster than sand left undisturbed.

Professor Dorn believes the ants collect calcium and magnesium and use these elements to make the limestone.

The conversion may occur when ants lick sand grains in order to stick them to the walls of their nests.

Alternatively, the limestone could be created from bacteria in the insects gut before it is excreted.

This process is similar to what’s known as carbon sequestration.

Natural carbon sequestration is the process on Earth that manages the carbon dioxide expelled by animals, plants and humans.

Trees and the oceans help convert or trap this carbon dioxide.

There are also artificial carbon sequestration schemes that involve manually trapping this carbon dioxide in the ground.

One proposed method is ocean sequestration, in which carbon dioxide is placed deep in the ocean, forming lakes of the gas.

These gases stay where they are due to pressure and temperature of the surrounding water, gradually dissolving over time.

Another method is geological sequestration where the carbon dioxide is pumped into underground chamber, or into areas full of magnesium and calcium.

Carbon dioxide reacts with these elements to form limestone and magnesite.

It is this latter method that Dorn believes the ants perform naturally.

But, Professor Dorn claims it is still unknown how much atmospheric carbon is removed by the ants.

The findings are published in the journal Geology.

Earlier this month, British scientists at the University of East Anglia said leafcutter ants could save lives thanks to a natural antibiotic they produce.

The pioneering research by the School of Biological Studies centred on a particular type of fungus the ants eat, and how the ants’ natural resistance protects it.