Many of Earth’s creatures have developed some kind of mutualistic interactions with other organisms, from pollinating bees and flowers to clownfish living within sea anemones for protection. Even the bacteria that live in the guts of humans and many other animals.

However, there are few interactions between different species odder or less expected than the super-shaggy water buffalos of Turkey and tiny marsh frogs. Scientists recently discovered this never-before-seen relationship and published their observations in the journal Acta Herpetologica.

During a series of field surveys at Kizilirmak Delta along the Black Sea coast, one of the largest wetlands in the Middle East in both spring and fall, biologists spotted 12 independent groups of water buffalos (Bubalus bubalis). Out of these, 10 of the groups had individual buffalos covered in small marsh frogs.

One popular buffalo had as many as 27 amphibians hanging out on it, although the average beast only had around 2 to 5. The frogs could be found all over their bodies, from perching on their heads to relaxing on their backs. The sheer number of times they observed it convinced the scientists there was something interesting going on here and it wasn't simply chance.

So what is behind this unlikely alliance? It’s pretty simple really: the frogs are using these huge mammals as a mobile restaurant, eating the flies that gather on their bodies.

The researchers found that there were more frogs hitching a ride during the fall, most likely because this is when food was more scarce. The researchers noted that this could be “a possible mutualistic interaction” where the frogs help the buffalo get rid of harmful or simply annoying flies, however, the study said they “cannot prove that water buffaloes have a tangible benefit from the presence of the frogs”.

There could be another factor at play. The cold-blooded amphibians might be latching on to the warm-blooded water buffalos as “an efficient heat source,” which would also explain why this is less common during the spring.

The researchers carried out an extensive search to see if this phenomenon has ever been documented before, skimming through everything from academic papers and new articles to YouTube videos and Google images. To the best of their knowledge, this is the first time it's been documented, let alone scientifically studied.