Tardigrade's improbable ride on nematode captures global intrigue

The recording that received the prestigious award surprised both experts and laypeople. It shows a tardigrade undertaking an unusual journey on the back of a predator dangerous to it – a nematode. Tardigrades, known for their exceptional survival skills even in harsh conditions, never cease to amaze scientists.

As reported by Business Alert, Nikon's Small World in Motion Video Competition awarded fifth place and a $600 prize for a fantastic recording made by Quinten Geldhof, a 24-year-old microscopy enthusiast. He captured an extraordinary moment – a tardigrade moving on the back of its natural enemy, a nematode.

Tardigrades, also known as "water bears," are tiny, eight-legged creatures famous for surviving in extreme conditions. They are among the most resilient creatures on Earth. Scientists have proven that the tiny invertebrates can withstand temperatures reaching 150°C, pressure over 6000 bar, decades without water, or high concentrations of chemical compounds that would be lethal to most life forms. Space is not a problem for them either.

About 1,500 species of tardigrades are known, inhabiting various ecosystems—from the poles to the tropics, from the highest mountains to the ocean floor. It is worth mentioning that they also live in Canada. In May 2024, Canadian scientists in the Czerniejewskie Forests, located in Poland, discovered a new species of tardigrade. The animal was named Mesobiotus mandatory, and this is just one example of "Canadian" tardigrades.

Geldhof’s recording shows one of these charming creatures riding on the back of a nematode – a predator that often eats tardigrades. "Nematodes often eat tardigrades, and so it felt like the stakes were quite high," Geldhof told Business Insider. "I had never seen anything quite like it," he added.

"It is one of those occasions that can occur but rarely do you have a camera handy to record the event," said Sandra McInnes of the British Antarctic Survey, referring to what was captured in the recording. Especially since the tardigrade in Geldhof’s film appears to be a species of Diphascon, averaging 0.36 millimetres in length. Paul Bartels, a tardigrade researcher and biology professor at Warren Wilson College, explained the practical aspect of this situation. "Tardigrades cannot walk on glass/plastic petri dishes. I believe this tardigrade simply encountered the nematode, and it was something it could grasp which is better than flailing around helplessly."

Geldhof collected moss from the sidewalk near his home in Winthrop, Massachusetts. He then used a Baermann funnel to filter the microorganisms. He obtained the nematode and several tardigrade eggs, which he kept on a glass slide in a home humidity chamber. After a few days, five young tardigrades hatched from the eggs. One climbed onto the nematode, which Geldhof recorded using a Swift 380B microscope and an iPhone 14 Pro.