Scientists find new organisms as they descend to 8,000 meters off the coast of Chile

Scientists descended 8,000 meters deep in the so-called Atacama Trench, on the northern coast of Chile, and where humans had never arrived, they discovered strange microorganisms about which they now have more questions than answers.

Chilean scientist Osvaldo Ulloa - director of the Millennium Institute of Oceanography at the University of Concepción - led the group of three people who at depths of up to 8,000 meters explored the enigmatic Atacama Trench, a huge gap in the Pacific Ocean that stretches 5,900 km from Ecuador to southern Chile.

“We did the feat of taking humans to the pit where no human being had ever arrived,” Ulloa, who performed the feat aboard the Limiting Factor submarine, tells AFP.

He was joined by the American explorer Victor Vescovo and the deputy director of the Millennium Institute, Rubén Escribano, on the so-called Atacama Hadal expedition, which began on January 13 and lasted for 12 days on the coast of Mejillones and Tal Tal, in northern Chile.

The conditions of the trip are extreme. At a depth of 100 meters the light no longer reaches and everything is silent, says Ulloa.

It was necessary to turn on powerful LED lights installed outside the submarine capsule for the group to observe what no human had ever seen before.

“We found geological structures and there we saw a type of holoturia or translucent sea cucumbers, like gelatin, that we didn't have registered and that were most likely (is) new species,” explains Ulloa.

“We also discovered bacterial communities that even had filaments that we didn't know existed in the Atacama Trench and that would feed on chemical and inorganic compounds, that opens up a lot of questions: what compounds are those? what kind of bacteria are they? We have no idea, we're going to have to go back there,” he predicted.

The expedition also found species of amphipods (Eurythenes atacamensis) - discovered there on an unmanned expedition in 2018 - scavenger crustaceans, segmented worms and translucent fish.

“The large population of these organisms found runs counter to what we knew: as the depth increases, the abundance and diversity of organisms decreases,” he added.

- Natural disasters —

The Atacama Trench is located in the same place where the Nazca plate and the South American plate collide, two tectonic plates responsible for the earthquakes and tsunamis that have frequently occurred in this area.

“We will put three sensors on the South American plate and two on the Nazca plate to see how the ocean floor is deformed, (now) these types of sensors only exist on land,” Ulloa said.

The sensors will let you know in which area there was no earthquake and energy is accumulating, which could help predict the site of an upcoming telluric event.

“It is a tremendously ambitious project; the largest experiment ever done in underwater geology here in Chile and there is a lot of interest from the international community to put more sensors and use this region to study all the processes associated with the collision of these two plates,” concludes the scientist about the observatory that will begin his installation in the second half of this year.

msa/pa/ag