New photos in Japan caught two animals in the act of devouring fungus root fruit and the millions of tiny seeds inside: land crabs and cockroaches.
Scientists were surprised to find that on the island of Ishigaki, land hermit crab (Coenobita brevimanus) and the Australian cockroach (Periplaneta australasiae) primarily disperse seeds of fungus root (Balanophora fungosa), a parasitic plant that looks like a mushroom.
The researchers first thought that ants were responsible for eating the fruit and spreading seeds. But careful experiments that excluded all but ants left the fruit untouched. The scientists then set up a waterproof camera near the plants and made a shocking discovery.
Hermit crabs carried an average of 86 fruits on their claws. They also ate and defecated intact viable seeds. Australian cockroaches defaced fungus root seeds, too, but fewer intact seeds than hermit crabs.
“This expands the range of ecological roles known for these animals and, more broadly, adds to growing evidence that small-bodied invertebrates can make meaningful contributions to seed dispersal,” study author Kenji Suetsugu, a professor of biodiversity and ecology at Kobe University, Japan, told Mongabay.
Suetsugu also noted the importance of studying unsung seed dispersers that aren’t birds or mammals.
