In the Red Sea off the coast of Egypt, bottlenose dolphins barrel through a soft, bushy coral. Looks like fun, but maybe it’s medicine.
Dolphins may rub on specific corals and sponges to treat their skin, researchers reported Thursday in the journal iScience. These stationary sea creatures may serve as drive-by pharmacies, dispensing a chemical cocktail that could treat bacterial or fungal infections or support skin health. The scientists said cetaceans have not been observed self-medicating before.
Angela Ziltener, a biologist who works at the Dolphin Watch Alliance in Switzerland, spotted this behavior in 2009. Dolphins lined up in front of a coral and each one took their turn, sometimes circling to the back of the line for another go.
The dolphins seemed to have clear preferences — out of hundreds of coral species in the reef, they used a select few, Ziltener said. Sometimes after the dolphins hit up a coral, their skin was stained yellow or green. Knowing that sponges and corals contain an assortment of chemical compounds, Ziltener connected with Gertrud Morlock, an analytical chemist, to investigate whether the dolphins’ behavior could be explained by what’s in the goo these creatures exude.
In 2019, the researchers snipped tiny pieces from two soft coral and one sponge species they had seen dolphins rubbing against in the Red Sea. Combining several powerful techniques, the team sleuthed for substances. Morlock said they found 17 bioactive compounds.
Some of these molecules may serve as immune boosters or sunscreens, said Julia Kubanek, a marine chemist.
She noted that the scientists didn’t report whether dolphins prefer to rub against corals and sponges that contain more bioactive compounds.
Self-medication “seems totally plausible,” said Eric Angel Ramos, a marine mammal scientist. “But equally it’s plausible that they just love to rub against it.”
He suggested testing whether the dolphins get a medicinal benefit from these invertebrates by working with captive animals. They often scratch, bite or otherwise beat up one another, which provides an opportunity to track how dolphins’ skin fares after some coral or sponge skin care.
The research team is working to analyze footage of thousands of dolphin rubs on corals and sponges, Ziltener said. That data could contain clues to whether the dolphins are getting an Rx on the reef. If some of them repeatedly dose themselves, that could bolster the case for self-medicating.
Elephants in mourning spotted on YouTube by scientists
It was 2013 when Sanjeeta Pokharel first witnessed Asian elephants responding to death. An older female elephant in an Indian park had died of an infection. A younger female was circling the carcass. Dung piles hinted that other elephants had recently visited.
“That is where we got curious,” said Pokharel, a biologist with the Smithsonian Conservation Biology Institute. She and Nachiketha Sharma, a wildlife biologist at Kyoto University in Japan, wanted to learn more. But it is rare to glimpse such a moment in person, as Asian elephants are elusive forest dwellers.
For a paper published in Royal Society Open Science, the scientists used YouTube to crowdsource videos of Asian elephants responding to death. Reactions included touching and standing guard as well as nudging, kicking and shaking. In a few cases, females used their trunks to carry calves that had died.
African elephants have been found to visit and touch carcasses. But for Asian elephants, Pokharel said, “There were stories about it, there was newspaper documentation, but there was no scientific documentation.”
Combing through YouTube, the researchers found 24 cases for study. Co-author Raman Sukumar of the Indian Institute of Science provided videos of another case.
The most common reactions included sniffing and touching.
Another frequent response to death was making noise. Elephants in the videos trumpeted, roared or rumbled. Often, elephants kept a kind of vigil over a carcass: They stayed close. Several tried to lift or pull their fallen peers.
There was one behavior that “was quite surprising for us,” Pokharel said: In five cases, adult females — presumably mothers — carried the bodies of calves that had died.
The observation was not totally new. Researchers have seen ape and monkey mothers holding deceased infants. Dolphins and whales may carry dead calves on their backs or push them up to the surface, as if urging them to breathe. Phyllis Lee, an elephant researcher, said she has seen an African elephant carry her dead calf with her tusks for a day.
Pokharel hopes understanding how elephants view death will help to better protect elephants, especially Asian elephants in frequent conflict with humans.
Scientists do not yet know to what degree elephants grasp the concept of death. But that does not make the animals so different from ourselves, Lee said. “Even for us humans, our primary experience is probably also loss.”
Watch a giant stingray’s safe return to its river home
After dawn May 5, scientists on a stretch of the Mekong River in Cambodia released a giant, endangered freshwater stingray caught on a fisherman’s line. It was 13 feet long and 400 pounds.
“It was shaking, and I told her, ‘Calm down, we will release you soon,’” said Chea Seila, a coordinator for the Wonders of the Mekong Project.
The stingray, Urogymnus polylepis, is the world’s largest stingray species. The animals slide across riverbeds in search of fish and invertebrates. Although they can grow to epic proportions, overharvesting for the meat, accidental deaths in fishing nets, and habitat fragmentation and degradation from dams, pollution and other human activities have made the animals endangered.
After receiving a call from the fisherman who caught the stingray, Chea and her team drove through the night to assist with its release.
Before freeing the stingray, the team took noninvasive samples that would help with future study. Then, they helped guide it back to the Mekong’s depths.
That a stingray of this size could still be found in these waters was extraordinary, the experts said.
“It shows you nature is so beautiful, but also resilient,” said Sudeep Chandra, a limnologist at the University of Nevada, Reno and co-scientist on the Wonders of the Mekong Project.
Much of what is known about big rivers as ecosystems comes from the Mississippi River and rivers in Europe. But all of these are in temperate regions, Chandra said. In contrast, the Mekong is tropical and prone to huge, seasonal deluges. This gives the Mekong a dynamic and mostly unstudied ecology, he said.
For instance, Chandra and his team were surprised to discover recently that beneath the Mekong’s surface, there were hidden pools more than 250 feet deep.
It is probable that such pools play an important role in the life cycle of the river’s giants. With underwater submersibles, environmental DNA sampling and sensors that can provide information about the river’s changes in real time, the scientists working with the Wonders of the Mekong Project hope to learn more about these habitats and protect them from environmental threats.
Chea has been working in these communities since 2005. That work seems to be paying off. Now, when someone accidentally hauls in a giant creature, they may reach for a phone instead of a filet knife.
Scientists found an animal that walks on three limbs. It’s a parrot.
Lovebirds are popular pets. The colorful parrots swing from ropes, cuddle with companions and race for treats in a waddling gait with all the urgency of toddlers who spot a cookie. But they also do something strange: They use their faces to climb walls.
Give these birds a vertical surface to clamber up, and they cycle between left foot, right foot and beak as if their mouths were another limb. In fact, a new analysis of the forces climbing lovebirds exert reveals that this is precisely what they are doing. Somehow, a team of scientists wrote in the journal Proceedings of the Royal Society B on Wednesday, the birds have repurposed the muscles in their necks and heads so they can walk on their beaks, using them the way rock climbers use their arms.
Climbing with a beak as a third limb is peculiar because third limbs generally are not something life is capable of producing, said Michael Granatosky, an assistant professor of anatomy at the New York Institute of Technology and an author of the new paper.
“There is this very deep, deep-set aspect of our biology that everything is bilateral” in much of the animal kingdom, he said. The situation makes it developmentally unlikely to grow an odd numbers of limbs for walking.
Some animals have developed workarounds. Kangaroos use their tails as a fifth limb when hopping slowly.
To see if parrots were using their beaks in a similar way, Granatosky and a graduate student, Melody Young, as well as colleagues brought six lovebirds from a pet store into the lab. They had the birds climb up a surface that was fitted with a sensor to keep track of how much force they were exerting and in what directions. The scientists found that the propulsive force the birds applied through their beaks was similar to what they provided with their legs. What had started as a way to eat had transformed into a way to walk.
Granatosky speculates parrots may have evolved this ability because they cannot hop up and down the trunks of trees. Parrots alternate their legs when they walk, rather than pushing off with both legs at once. So when it came to moving vertically, they had to come up with something that created the third limb.
How often parrots do this three-limbed walking is another question researchers have.
This article originally appeared in The New York Times.