Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news about fascinating discoveries, scientific breakthroughs and more.
CNN
—
While observing a group of golden-backed frogs congregating in a roadside pond in Karnataka, India, a group of naturalists noticed something unusual about one of the amphibians — the animal had sprouted a small mushroom from its side.
How a seemingly healthy frog came to nurture its fungal partner — a previously undocumented phenomenon — has baffled scientists, according to a paper published in the journal in January. Reptiles and amphibians.
“When I first noticed the frog with the mushroom, I was amazed and intrigued by the sight. YT was part of the team that discovered the frog,” Lohit YT, a rivers and wetlands specialist at World Wildlife Fund-India in Bangalore, said via email. , my intention was to document it. We wanted this to be a rare occurrence and not a fatal event for the frog.
Race – known as Raw's intermediate golden-backed frog, or the scientific name Hylarana intermedia – is found in abundance in the southwestern Indian states of Karnataka and Kerala. Frogs are small, growing up to 2.9 inches (7.4 centimeters) in length.
When the naturalists looked at the frog with the fungal growth, the animal moved from the center of the branch it was sitting on to the tip, turned and changed positions, but the mushroom remained in place, YT said. The group did not touch the frog.
Lohit Y.D
The frog moved from the center of the branch it was sitting on to the very tip, turned and changed positions, but the mushroom remained in place, YT said.
The authors found the amphibian in June 2023 and did not collect it, so neither the cause of the event nor the fate of the frog is known.
But through pictures, mycologists later identified it as a mushroom growing on the frog's side. Common Bonnet, part of the genus Mycenae, is a type of fungus that often grows on rotting wood from dead trees, the authors wrote in the published paper. A fungus saprotrophic decomposerA mushroom that usually gets its nutrients from dead or decaying organic matter – but a 2023 study It was found that the mushroom can also thrive on living plants.
A 2023 study suggested that Mycenaean fungi can form a symbiotic relationship with living plants or trees, meaning that both the plant and the fungus growing on it benefit from the arrangement—both fungi take up nutrients and exchange them. The plant host. In trees, the authors added, Mycenae can be helpful by pruning dead branches.
The prognosis of a frog with mushroom hitchhiker is unknown, but there are a few theories about the cause of the condition.
Alyssa Veterau Kaganer, a postdoctoral assistant in the Department of Public and Environmental Health, said when she first saw the report that the frog had a mushroom attached to its side. Cornell University College of Veterinary MedicineThe discovery was fascinating.
“Fungi are organisms that adapt to changes in their environment, and by exposing them to new potential hosts in different environments or climates they may grow in places we did not previously expect,” he said in an email.
Although it is difficult to predict the fate of the frog without further study, “an otherwise healthy frog can tolerate moderate colonization of its skin by this fungus without any adverse health effects,” Kaganer said. Fungal infections are very common in frogs, however, if the fungus “overgrows the skin or burrows into the animal's body, the animal can develop symptoms of a fungal disease,” he added. Gaganer was not involved in the invention.
There are many types of fungi that can infect frogs, and fungus-frog interactions have yet to be discovered. A frog with signs of fungal disease, such as “altered frog behavior” or “skin damage including ulceration or tumor-like nodules,” has an infection that often results in death in at least some of the infected animals, Kaganer said. .
Anything out of the ordinary, including fungal growth like this, is a concern for frog species, he said Karthikeyan Vasudevan, Chief Scientist at the Laboratory for Endangered Species Conservation at the Center for Cellular and Molecular Biology, Telangana, India. Vasudevan was not involved in the discovery and was surprised by the discovery.
“Sick animals have very little chance of survival in the wild. Sick animals are difficult to observe because they die or are eaten quickly. So, something like this is interesting and should be followed up with observations and screening of frogs,” Vasudevan said in an email.
Initially, Vasudevan thought the mushroom was stuck to the frog's skin rather than a growth, but photographs of the animal convinced him otherwise. “It's actually like a living mushroom on a living frog,” Vasudevan said. “But one of the possibilities is that there was a small piece of wood debris on the frog's skin that got lodged in the skin and a mushroom grew from it.”
India is currently facing an epidemic of the frog-killing disease chytridiomycosis, a fungal infection that affects more than 700 species of amphibians worldwide. The disease is present at low levels in all frog hotspots across India, the authors of the new note wrote.
Cytrid disease is an example of a common amphibian and fungal interaction. But the authors don't know if this is related to this finding, YT said.
“This particular type of mushroom is not closely related to the species of fungus that causes chytridiomycosis, so I am not concerned that this mushroom is a direct symptom of chytridiomycosis,” said Kaganer, who studies the disease. “However, the frog with mycenae may have altered susceptibility to a chytrid infection.”
The mushroom-sided frog may be more susceptible to chytridiomycosis because it is compromised by Mycena, or “because Mycena kicks the frog's immune system into high gear, it may become more immune,” he added.
“We have no hope of following the frog because this is not a common occurrence,” YT said. He added that the teachers would visit the site again in the next monsoon when the weather would be hot and rainy and frogs would be abundant.
“If we can find it, that would be great,” YT said. “This place has been frequented by many enthusiasts and experts. It would be great if some researchers could get their hands on it and could continue the investigation further, but again, that's unlikely to happen.
