For the very first time, a team of German researchers has spotted the presence of calcium phosphate in the structure of plants, used to harden hairs that are used to repel predators. This substance makes up a large part of bones and teeth.
It was a team of researchers from the Rhine University of Frederick William in Bonn, Germany, who recently succeeded in discovering the first plants to use calcium phosphate as a bio-mineral structure. Calcium phosphate is a hard mineral substance of which bones and teeth are largely made up, therefore very widely found in the animal kingdom. Here, for the first time, it was found in the stinging hairs of Loasaceae, a plant native to the Andes of South America.
The minerals work by strengthening trichomes, tiny stinging hairs that act as repellents for herbivorous predators. When an animal’s tongue comes into contact with the trichomes, their hardened ends break off and a « painful cocktail » is dropped on that tongue. » The mechanism is very similar to that of our nettles“, says Maximilian Weigend of the Nees-Institut for Plant Biodiversity at the University of Bonn, who participated in the study published in the journal Nature. But the process here is different from that of the nettle, whose hairs are hardened with silica.
» The mineral composition of stinging hairs is very similar to that of human or animal teeth. It is essentially a composite material, similar in structure to reinforced concrete tells us Maximilian Weigend. Indeed, although the structure of the trichomes is made up of the fiber of the cell walls of the plant, tiny crystals of calcium phosphate are widely present, making the stinging hairs extremely rigid, like needles.
Researchers do not yet explain why these plants evolved this unique type of bio-mineralization. » A common reason, for all given evolutionary solutions, is that an organism either has or lacks a particular metabolic pathway. But since the Loasaceae are able to metabolize silica, why calcium phosphate? asks Maximilian Weigend. » At present, we can only speculate on the reasons for this adaptation. But it seems that they reimburse in kind, tooth for tooth he concludes.
Source: natural