科学美国人60秒:Reindeer Spit Smacks Down Plant Toxins

Reindeer spit is in the news. Well, now it is. You see, reindeer and moose eat plants that contain toxins entrusted with keeping the vegetation from being so desirable. But now we know that the animals’ saliva can prevent the production of those toxins. The slick finding is in the journal Biology Letters. [Andrew J. Tanentzap, Mark Vicari and Dawn R. Bazely Ungulate saliva inhibits a grass–endophyte mutualism]
 
Generally speaking, plants do not like to be eaten. And many have defenses to avoid this fate. The red fescue that’s favored by European reindeer and moose maintains a mutually beneficial relationship with a fungus. When the host plant gets munched on, the resident fungus churns out a toxin called ergovaline. This chemical restricts blood flow to the grazer’s extremities, which can lead to the loss of limbs.
 
But the battle doesn’t end there. Because researchers found that when reindeer and moose drool is dribbled over plants, ergovaline production goes way down. 
 
The specific secret of the spit is still unsolved. But the researchers think that compounds in the saliva interfere with the chemical signals that switch on toxin production when the plants get ‘et. One thing they know for sure: as they write in their report, and who can argue, the “salivary secretions of large mammals are more important than previously realized.”
 
—Karen Hopkin
 
(The above text is a transcript of this podcast)