Some plants evolve tolerance to deer

Rampant deer have long been munching away on forest plants and altering ecosystems, but new evidence suggests some plants are evolving tolerance to being eaten. An experiment with 26 populations of orange jewelweed ( Impatiens capensis ), a common wetland native plant, found that historically browsed populations tolerated being eaten by deer far better than historically protected plant populations. Deer tolerance was determined by measuring lifetime seed production when faced with being eaten by deer. The study , recently published online in the Journal of Ecology, found that herbivory by deer reduced lifetime fruit (seed) production by only 20 percent in historically browsed populations, versus reductions of 57 percent in historically protected plants. The researchers believe that more tolerant plants may put more energy into growing fast to counter being eaten, or in this case, producing more seeds. "Individuals in populations that were historically browsed were able to devote more resources to seed production," said Laura Martin, a graduate student in the field of natural resources and the paper's lead author. "The flowers last longer and there were more seeds per flower in the historically browsed plants, but there were the same number of flowers in browsed and protected plants," Martin said.