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Hoboro Island off the coast of Japan may soon be an island of the past, and it’s primarily due to one unsuspecting isopod.

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Hoboro Island off the Coast of Horoshima Japan was never very big, but folks have noticed that it is slowly shrinking. The island was 22 meters high in 1928, but it's only 6 meters high today. It's not clear how long it has left, but some people have guessed it could disappear in the next century.

And it is not being worn away by the wind or the waves, at least not directly. Now I'm gonna guess that you're not gonna predict this: the island is literally being eaten by bugs. Actually, not bugs precisely. They are small crustaceans related to wood lice called "sphaeroma sieboldii".

Researchers believe they bore holes into rocks to protect their mates and eggs. And these little holes expedite natural erosion from water, which breaks off pieces of the island and then washes them away. While there does not seem to be a ton of research about Hoboro specifically, the phenomenon of bioerosion is actually pretty well studied in general.

And it's worth understanding because it doesn't just come for small rocky islands off the coast of Japan, but for whole ecosystems. The perpetrators may include creatures from animals to plants to microbes, who bite, burrow, or chemically dissolve anything from wood to coral, and even solid rock. 

Plant roots can fracture rocks apart. Microbes and fungi break down minerals in soils. Even the footfalls of penguins wear down the bedrock of islands. Around the world, there are tons of examples of bioerosion. 

An isopod closely related to those on Hoboro Island can bore centimeters deep into sandstone in Mylasia