Eggs survive through avian guts-A possible mechanism for transoceanic dispersal of flightless weevils.

How flightless animals disperse to remote oceanic islands is a key unresolved question in biogeography. The flightless weevils represent repetitive colonization history in West Pacific islands, which attracted our interests about how some weevils have successfully dispersed in the reverse direction against the sea current. Here, we propose endozoochory as a possible mechanism that the eggs of the weevils might be carried by embedded in the fruits as the food of frugivorous birds. In this study, eggs were embedded in small pieces of persimmon fruits () and fed to captive frugivorous birds. After digestion, 83%-100% eggs were retrieved from the feces of a bulbul () and two thrushes (). The retrieved eggs had hatching rates higher than 84%, which were not different from the control. In contrast, no egg was retrieved from the feces of the frugivorous pigeon (), which took a longer retention time in the guts. Our study identified that the eggs of weevils are possible to be transported by internal digesting in some bird species.