Study: Snails Can Travel Via Bird Poop
A Japanese study has revealed that a whopping 15% of the tiny land snail Tornatellides boeningi can survive being eaten by local birds. Great, wonderful. Lucky snails only have to endure the horrors of soaking in acid and then the indignity of being pooped out of a bird, but live to fight another day, huh? There’s more.
Scientists have wondered how micronsnails are able to spread over such huge expanses. But this study has shown the tiny critter’s ability to pass through a bird’s digestive system alive has likely played a role in spreading the snails’ population. Researcher Shinichiro Wada explains, as quoted by BBC Nature:
Biogeography of wingless terrestrial invertebrates, in particular snails, is often faced with mysterious long distance dispersal patterns that can only be explained by hand waving arguments involving birds’ feet or guts or cyclones, […] This is the first study showing that birds can indeed transport a substantial [number of] micro land snails in their gut alive.
In the same study on Hahajima island in the Ogasawara Group archipelago, scientists looked at the genetic diversity of microsnails. They found that while there are many, many snails on the island the disperate members of T. boeningi managed to find each other and mate. The scientists concluded that the snails’ resistance to being digested has helped spread them across the island, much like how berry seeds are also spread by pooping birds. For the snail, the entire experience is probably only slightly worse than having to take a ride in a shifty taxi at 3 AM.
A final hint as to how the snails managed to establish populations via digestive travel came when researchers observed one snail, found alive and well in a recently expelled blob of bird droppings, give birth. Lovely.