What do leafcutter ants and scores of middle-school students have in common? A mouth full of metal-laced teeth.
Tiny arthropods such as ants, spiders and scorpions routinely bite, sting or otherwise pierce tough material like wood and skin. It’s a remarkable feat, given that humans have trouble chewing through so much as a piece of beef jerky (let alone a hunk of tree bark), even with our strong jaw muscles.
But new research has shed light on what gives one group of leafcutter ants (Atta cephalotes) their biting edge.
Using powerful microscopes, scientists have discovered a web of zinc atoms woven into the biological
structure of the ants’ jaws, lending them the durability of a set of stainless steel knives, the researchers said.
This smooth distribution of zinc allows the edge of the ant’s teeth to form a fine point — and it keeps them sharp for a long time.
“The tiny animals who had this material, their muscles are microscopic compared to ours,”
Robert Schofield, a biophysicist at the University of Oregon and lead author of the study, told Live Science.
The trick, he said, is that ants and other metal-mouthed arthropods leverage their sharp chompers to apply precisely the right amount of cutting force to slice through leaves or hide.