Even bacteria have learned to diversify, a key survival strategy for everything from stock market portfolios to forests challenged with environmental stress.

This quality was revealed by University of Iowa research published in the Proceedings of the National Academy of Sciences.

The research showed that when disease-causing bacteria assemble into communities known as biofilms, the individual bacteria rapidly diversify. This diversity increases the capabilities of the group and provides a form of "biological insurance," which protects the organisms from adverse conditions.

"Biofilm infections are a major medical problem, and one focus of our lab is to understand why the biofilm lifestyle makes bacteria so difficult to eradicate," said Pradeep Singh, M.D., assistant professor of internal medicine and microbiology in the UI Roy J. and Lucille A. Carver College of Medicine.

"Our findings raise the intriguing possibility that bacteria may have evolved mechanisms to produce diversity when they sense they are part of a group," Singh said.

It may also shed light on why chronic infections caused by biofilms are so difficult to eradicate.