Thus, the plant has turned a seed-eating rodent into a seed spreader that helps the plant reproduce, says a new study by Utah and Israeli scientists.

"It's fascinating that these little mice are doing analytical chemistry, assaying the fruit for toxic compounds" and learning not to bite into the seed, says Denise Dearing, a coauthor of the study and professor of biology at the University of Utah.

"It adds a new dimension to our understanding of the ongoing battle between plants and animals," she adds. "In this case, the plants have twisted the animals to do their bidding, to spread their progeny."

The study was set for online publication June 14 in the journal Current Biology.

The study illustrates the first known case within a single species of what is known as the "directed deterrence" hypothesis, namely, "the fruit is trying have itself eaten by the right consumer one that will spread its seeds," Dearing says. "The plant produces a fruit to deter a class of consumers that would destroy its seeds."