Mysterious, Deep-Sea Golden Orb May be From a Giant Sea Anemone
In 2023, divers participating in a deep-sea expedition 3,250 meters below the surface discovered something very unusual: a golden blob stuck to a rock.
The curious specimen could not be categorized, but suggestions abounded. Ideas put forward included an egg crate, a dead sponge and a piece of coral. Now researchers seem to have the answer: the golden orb is the remnant of a species of giant deep-sea anemone called Relicanthus daphne.
“Very often, when exploring the deep oceans, we discover captivating mysteries, like the ‘golden orb.’ With advanced technologies like DNA sequencing, we are able to solve more and more,” said CAPT William Mowitt, acting director of NOAA Ocean Exploration, in a press release. “This is why we continue to explore: to unlock the secrets of the deep and better understand how the ocean and its resources can drive economic growth, strengthen our national security and preserve our planet. »
A preprint describing the research was published in bioRxiv while the paper awaits peer review.
Examining the Physical Properties of the Golden Orb
The golden orb was discovered during a NOAA ocean exploration expedition to the Gulf of Alaska more than two years ago, and its identity has puzzled scientists ever since. To solve the mystery, researchers studied its physical characteristics and carried out genetic analysis – but the process turned out to be less straightforward than initially thought.
“We are working on hundreds of different samples and I suspected that our routine processes would unravel the mystery. But this turned into a special case that required concentrated efforts and the expertise of several people,” Allen Collins, a zoologist and director of NOAA’s National Fisheries Systematics Laboratory involved in the research, said in a press release. “This was a complex mystery that required morphological, genetic, deep-sea and bioinformatics expertise to solve. »
During an initial investigation, the team could not identify any muscle tissue or any other features indicative of animal anatomy, but a closer examination revealed that the surface was full of stinging cells called cnidocytes. They are commonly found in cnidarians, a group of invertebrates including corals, anemones and jellyfish.
The cells turned out to be a specific type of cnidocyte called spirocysts. This information allowed the team to further clarify the identity of the object. Spirocysts are only found in a specific group of cnidarians: the Hexacorallia.
Learn more: Carnivorous death ball sponge and other new species discovered in the deep sea
Decoding your genome
Attempts to identify the orb through a technique called DNA barcoding failed – a result that researchers attribute to the confusion caused when the technology detected the DNA of other microscopic life forms present on the orb. However, attempts at whole-genome sequencing have proven more successful.
Although the orb does not exhibit any anatomy commonly associated with animals, sequencing identified animal DNA. Specifically, it revealed genetic material from a species of giant deep-sea anemone.
When researchers sequenced the mitochondrial genomes of the golden orb and another specimen collected during a 2021 expedition, they found that both were nearly identical to a reference genome from a species of anemone called Relicanthus daphne. These results suggest that the “golden orb” is a remnant of dead cells from a giant anemone.
R. daphnea is distributed globally and exists at depths between 5,469 and 12,952 feet (1,667 and 3,948 meters). According to a study published in Scientific reportsit is usually purple-pink in color and has exceptionally long tentacles that can reach two meters in length.
“Delightfully strange”
If the mystery is solved, the case shows that the ocean is full of surprises.
“Isn’t the deep sea so deliciously strange?” said Sam Candio of NOAA Ocean Exploration in a press release in 2023, at the time of the discovery. “While it is somewhat disheartening to be baffled by this discovery, it reminds us how little we know about our own planet and how much we still have to learn and appreciate our ocean.”
Learn more: The Mariana Trench plunges to 36,000 feet – hiding mysterious creatures and a bottle of beer
Article sources
Our Discovermagazine.com editors use peer-reviewed research and high-quality sources for our articles, and our editors review the articles for scientific accuracy and editorial standards. See the sources used below for this article:
