Michigan State University Assistant Professor Carolyn Malmstrom and colleagues isolated historical viral RNA sequences in native and invasive grasses and found implications for the ways viruses behave today.

"This work points out that the virus world does have an active, long-term role in nature, not just in agriculture," Malmstrom said. "We very much need to understand how viruses can move and influence our crops."

Malmstrom said little is known about viruses in nature. But recent advances in molecular techniques have unveiled natural systems teeming with viruses -- and thus raise the question of what impact such viruses exert.

"We've always assumed viruses largely are manifested in agricultural systems, because the system is unbalanced due to human interaction," Malmstrom said. "But now we are understanding viruses are more common in nature than people realize -- and that there's a whole class of biological interactions going on out there that we know hardly anything about."

The study is detailed in the Journal of Ecology.