For decades, the Great Salt Lake of the United States was thought to officially harbor only two animals larger than a hive: brine shrimp and brine flies.
Apart from that, bacteria and algae are only found in the highly saline lake water.
Now, scientists have discovered a third form of multicellular life that can also ingest a not-so-tasty amount of salt. He was hiding in the lake the whole time.
Breaking up calcium carbonate clay blocks is called Microbesbuilt by microorganisms on the lake floor, researchers at the University of Utah have confirmed what biologists have long suspected: There are worms of different species wriggling beneath the lake's surface, far from our eyes.
It is the saltiest environment in which nematodes have ever been found. This is saying a lot because nematodes live in every harsh environment on the planet.
Biologists Julie Young and Michael Werner led the team that discovered the worms. In the spring of 2021, they began an aggressive hunt for these creatures in a patch of the lake that is three to six times saltier than the ocean.
“At first it was just collecting samples of clips. But once we noticed it Microbes“We scooped up small pieces of it, tried to preserve the layers, and brought it back to the lab.” He explains Jung.
Where other biologists failed, Young and Werner succeeded.
Using powerful technology to separate large molecules such as DNA, RNA and proteins, the biologists identified live nematodes at each site where they collected samples.
“I looked there myself for them, but I didn't look in the same places…” He says Biologist Byron Adams of Brigham Young University, who consulted on the discovery.
“Even today we discover these amazing things about this lake that has been on our doorstep for 170 years.”
Researchers suspect that these hidden worms feed on the bacteria that live in them and form these mats. It may also protect the worms from the sun and from dehydration when the lake water recedes.
Researchers couldn't grow nematodes in the lab, so to find out how they survive, the team turned to the most studied roundworm ever: Certain types are elegant.
In the laboratory, this creature was also fed coli bacteria Bacteria or bacteria that live in the microbial mats of the Great Salt Lake. The worms were then exposed to lake water, which is 50 times saltier than that of the lake C. elegans Usual habitat.
Five minutes later, the worms are fed coli bacteria He perished. But those infected with microbes from the Great Salt Lake survived for longer than 24 hours.
“We didn't expect it to work, but it did.” He says Werner.
The results suggest that there is something in this special diet that allows Great Salt Lake roundworms to survive.
Genetic analyzes indicate that up to 80 different nematodes were collected from brackish and very saline sites in the lake.
Three of them belong to a genus that lives in marine and coastal sediments. The vast majority of the remainder did not match any other known genus or species of nematode.
Researchers believe these new worms are unique to the Great Salt Lake, which created after a long period of reproductive isolation.
Just as we have discovered this new habitat and new species, they are in danger of becoming extinct forever.
Today, the Great Salt Lake is a mere shell of its former self. As water is diverted for human use and the climate dries up, the banks recede, exposing microbial mats to the elements and increasing the salinity of the remaining water. Because the lake dried up, Werner and Jung had to ditch their kayaks and use mountain bikes to reach some sites during certain seasons.
Some scientists believe that the lake has less than five years before the entire ecosystem collapses. Who knows what will happen to his worms at that point.
“There is an urgent need to understand this essential community and the limits of its habitability.” We conclude Werner, Young, and colleagues.
The study was published in Proceedings of the Royal Society B: Biological Sciences.