Close-up of magnetic bacteria residing in the deepest part of the ocean

While hunting for meteorite dust, Yang was surprised to discover a shelled creature caught in his tool. It was a vertebrate named Resigella bilocularis. Like other foraminifera species, R. bilocularis is a single-celled animal, but unlike most foraminifera found on the ocean floor, this species contains something that amazes Yang: magnetism. Excited by his discovery, Yang decided to put all his efforts into finding out all that was related to this mysterious creature.

Resigella bilocularis under a microscope.

Many organisms such as bacteria, unicellular algae, insects, mollusks, fish, birds, and even mammals have magnetic affinity. This power is thought to come from the mineral magnetite, which species use to direct and modulate behavior according to the Earth's magnetic field. Some organisms can produce magnetite on their own using iron from the surrounding environment. But for many species, such as foraminifera and other eukaryotes, the origin of magnetite remains a mystery.

Talking about their research, Yang and his team suspect that R. bilocularis has made its own magnetite. If so, R. bilocularis would be the first magnetic single-celled eukaryote found deep in the ocean. Learning more about this species' magnetism could bring researchers closer to the evolutionary history of similar creatures.

The scientists came up with the hypothesis after analyzing 1,000 samples of foraminifera they collected from the Mariana Trench during expeditions between 2016 and 2019. Their work revealed a chemical and physical structure of magnetite in R. bilocularis differs from magnetite in the surrounding sediments, suggesting that foraminifera produced these substances on its own.

Despite the difficulties of studying foraminifera in a laboratory designed for single-celled organisms where pressures are 1000 times higher than sea level, Yang was determined to go ahead with his plan. He is working hard to keep foraminifera alive in the lab and sequencing the organism's genome. If successful, what Yang and his colleagues bring to biology will be enormous.

Resigella bilocularis reacts when exposed to a magnetic field

M. Renee Bellinger, an evolutionary biologist at the University of Hawai'i in Hilo who was not involved in the study, said: 'Magnetic self-production in species is rare, especially in biology. unicellular eukaryotes. Studying organisms from ancient deep-sea environments can help understand how the ability to create magnetite was formed.'

Although Yang has not yet deciphered the cosmological origin of life on Earth, he is perhaps one step closer to understanding the origin of life from the magnetic field.