Researchers at the University of Connecticut think this may explain why genetically similar moss species crop up thousands of miles apart, and nowhere in between.
Lead researcher Lily Lewis, writing in the journal PeerJ, says her team found moss fragments trapped in the feathers of long-distance birds.
Three of the species found carrying the potentially transplantable life forms build shallow nests by scraping mossy beds with their breasts, feet and beaks.
Lewis and colleagues are now working to see if the plant fragments found on the birds can grow in the lab.
There are potentially hundreds of thousands of plant parts being carried across the equator each year by migratory birds, Lewis says.
Photo: Jean-François Lamarre, CC BY SA