In a study published in Biology Letters , British and Canadian biologists collected the saliva of reindeer and moose and daubed the spit on grass clippings.

Moose have evolved a secret weapon that helps them eat grass containing potentially toxic fungi: spit. Until now, biologists were puzzled by the fact that moose ate so much red fescue grass -- known to contain a harmful fungus -- without appearing to suffer any ill effects.

"We found that the saliva worked very quickly in slowing the growth of the fungus, and the fungus colonies," says Dawn Bazely, a biologist at York University in Canada, in a press release. After applying the spittle over the course of two months, the researchers were also able to lower the concentrations of the fungal toxin in the grass between 41 and 70 percent.

"We know that animals can remember if certain plants have made them feel ill, and they may avoid these plants in future," Bazely says. Because moose graze repeatedly in a home patch, she believes grasses in moose territories might be continuously exposed to to saliva, and therefore be less toxic.

"This study is the first evidence, to our knowledge, of herbivore saliva being shown to 'fight back' and slow down the growth of the fungus," Bazely says. Don't underestimate the power of moose drool.