Myrmelachista ants (IMAGE) University of Utah Caption Myrmelachista ants, which excavate nesting cavities in living tree stems, keep understory leaves free of debris and pathogens. Credit Rodolfo Probst, University of Utah Usage Restrictions Editorial use only License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.