This deep-sea creature can survive more than five years without food, scientists discover

A creature that resembles the humble pill bug found under garden pots has revealed one of the ocean’s most remarkable survival secrets.

Deep beneath the ocean surface, where food is so scarce it can take years for a meal to arrive, giant deep-sea isopods have evolved a sophisticated biological system that allows them to survive without eating for more than five years, according to a new study published in the journal Cell.

The findings help explain how life persists in one of Earth’s harshest environments — a world of perpetual darkness, near-freezing temperatures and crushing pressure.

Researchers from the Chinese Academy of Sciences found that species including Bathynomus jamesi and Bathynomus doederleini rely on a combination of anatomy, microbes and genetics to stretch a single meal over several years.

Unlike most animals, deep-sea isopods have enormous stomachs that occupy roughly two-thirds of their abdominal cavity. The oversized organ allows them to consume and store exceptionally large meals whenever food becomes available before releasing nutrients gradually over long periods.

The animals also maintain an unusually slow metabolism, conserving energy while extracting as much nutrition as possible from each meal.

Scientists likened the deep ocean to a biological desert where organic matter falls only occasionally from the surface in tiny particles often described as “marine snow.” Larger food sources, such as whale carcasses or dead fish, are even rarer, making feast-or-famine survival essential.

The study also uncovered an unexpected ally living inside the crustaceans.

Beneficial bacteria belonging to the Chlamydiae group appear to help the animals store fat more efficiently, creating a steady energy reserve while maintaining a mutually beneficial relationship with their hosts.

Perhaps the most surprising discovery involved a gene known as ND1, which researchers believe entered the isopods’ genome through horizontal gene transfer — a rare process in which genetic material moves between unrelated species rather than being inherited from parents.

Laboratory experiments suggested the gene functions like an energy-management switch, improving survival during starvation while helping organisms cope with cold environments.

Scientists say the findings could extend beyond marine biology.

Understanding how animals naturally regulate metabolism and survive prolonged starvation could inform future research into human medicine, energy conservation and even robotic systems designed to operate for long periods in extreme environments.

The research also sheds light on how deep-sea ecosystems function at a time when scientists are racing to understand one of the planet’s least explored habitats.

According to the World Wildlife Fund, the deep sea stretches from about 200 metres to nearly 10 kilometres below the surface and remains one of Earth’s least understood ecosystems despite providing vital environmental services.

The discovery comes as interest in the deep ocean continues to grow, with scientists and environmental groups urging greater understanding of its biodiversity before commercial activities such as deep-sea mining expand further.