Alternatives to milk are emerging one after another. There’s oat milk, there’s goat milk, and now there’s amphibian milk (though it’s not on grocery store shelves). A team of Brazilian biologists has documented that a legless subterranean amphibian mother produces a milk-like fluid rich in fats and carbohydrates for her offspring.research Released on March 7th in diary science This is the first known example of an egg-laying amphibian feeding its babies with “milk.” The findings reveal new bodily functions and the potential for complex communication in understudied eccentric animals.
Non-dairy discoveries
Milk is generally associated with mammals.After all, the word “mammal” comes from the Latin breast “Breast” taxonomically refers to the mammary glands that produce milk. But mammals aren’t the only animals that feed their babies with special secretions. Pigeons, penguins and flamingos have “crop milk”. This is a sticky substance that both male and female bird parents make in the lining of their digestive tracts. Some spiders and cockroaches also produce milk for their multilegged young. Paper wasps are insect-like relatives of frogs, toads, and salamanders that live primarily in tropical regions.
American paper wasp (Siphonops anulatus) is one of the approximately 220 species of the Caricinidae family known worldwide, and is the newest addition to the list of animals that can be milked.Strange, almost blind creatures live in secrecy lives in the soil and under fallen leaves in the forests of South America And grasslands. “These animals are among the least understood vertebrates because they are so difficult to access,” he says. carlos jared, senior study author and integrative biologist at the Butantan Institute in São Paulo, Brazil. But it’s worth the effort, he added, because paper wasps are a “surprise box” that constantly provides unexpected biological treats.
Through years of careful research, collection, and observations in the wild and in the laboratory, Jared and his colleagues have conquered uncharted territory and made the following surprising discoveries: S. annulatus. Jared said it was recently discovered that amphibians feed their young with a clear, viscous liquid that is “the consistency of honey.” The American paper wasp secretes this nutritious milk through its “vent”, a multipurpose opening at the back end of its body, through which waste products and eggs are also expelled. In other words, these vertebrate worms feed their offspring with milk from their butts.
“This is an exciting discovery of incredibly interesting reproductive modification,” he says. marvary wake, an integrative biologist at the University of California, Berkeley. Wake was not involved in the new study, but he has studied paper wasps extensively and wrote a Perspective to accompany his work. science. The findings “challenge existing understanding of the evolution of parental care,” she wrote in the note.
devoted parents
Some paper wasps live and give birth, but the American paper wasp lays eggs. The mother protects her chicks closely. Even after the baby hatches and emerges with a small, slimy body, the mother continues to spend about two months nursing, discarding her food to provide the baby with sufficient nutrition. Previous research Research by Jared et al. documents some of the unconventional parenting methods of American paper wasps. While raising offspring, the amphibian mother’s skin changes color and develops a fatty outer layer. The offspring use special teeth to scrape it off and eat it as a meal.
(He clarified that he meant no harm to his mother.) marta antoniazzi, co-author of the new study and previous skin feeding study, and researcher at the Butantan Institute. ) But his new research makes it clear that paper wasps have more than just skin in their prey. An energetically expensive additional food source. Studies show that females lose an average of 30% of their body weight to feed their young.
follow up past observations Noting that paper wasp chicks spend much of their time around their maternal vents, Jared, Antoniazzi, and their collaborators collected 16 female paper wasps and their chicks from beneath the forest floor of a cocoa plantation. was collected. Unearthing the research targets was “difficult” and required “a lot of patience,” Jared said. In the lab, animals were kept in tanks designed to mimic their natural environment and cameras were installed to record them. S. anulatus Parental care. The researchers found that hatchlings ingest secretions through their mothers’ vents and that such feedings occur multiple times a day, much more frequently than once-a-week skin feedings. I confirmed that there is. The study found that after each drink of milk, the chicks become less active and begin to lie around “with their bellies turned upward, clearly indicating a feeling of fullness.”
Milk supply in the paper wasp Siphonops annulatus. Speed increased by 600x.Credit: Mailho-Fontana et al.
By analyzing thin layers of tissue from various organs, biologists discovered that milk is produced by special glands that appear only during the nurturing period. These temporary glands form in the skin of the paper wasp’s oviduct, which corresponds to the oviduct in mammals.
It has been known for decades that some species of living paper wasps produce secretions in their oviducts to internally nourish their young. previous research From Wake. But it’s surprising that egg-laying species do the same thing. “The established theory, based on all known similar species, is that even if the egg-laying mother provides some care or stays with her young for a while, no such provision exists,” Wake says. . “It’s really refreshing to switch to something that a living person would do,” she added.
More surprises
evaluate S. anulatus According to , scientists extracted fluid from five paper wasp mothers using careful massage and the help of gravity. Pedro Mailho Fontana, lead study author and another researcher at the Butantan Institute. Multiple analyzes revealed the presence of carbohydrates and fats. (Antoniazzi says Lingda Acecilian milk lacks protein, but the mother’s skin compensates for the nutritional deficiency.) Research shows that two types of acid, palmitic acid and stearic acid, Fatty acids account for more than 90% of the total milk fat in Acecilian Acecilian. His three main fatty acids found in amphibian milk also make up an important part of milk’s composition.
Then the cameras caught more surprises. Maillo-Fontana said the newly hatched chicks make clicking and wriggling movements near the vents before drinking milk. He and his colleagues found that the frequency of these sounds and movements peaked just before milk appeared, suggesting that the offspring were begging and the mother was responding. “Most amphibian biologists are quite conservative about claiming that there is communication, but based on the records this team has, it’s completely plausible,” Wake says. She points out that this kind of vocal solicitation is unique among amphibians and is just another way these strange animals distinguish themselves.
What lies ahead?
The researchers hope to conduct a follow-up study to further investigate the offspring’s vocalizations. Wake would like to see additional research assessing the hormonal cues that paper wasp mothers use to prepare for parental care. “There’s so much more to discover about these animals,” Jared says. Even with this series of new discoveries, much remains unknown. Perhaps, as Jared suggests, burrowing amphibians could play an important role as soil engineers to help plants grow. Maybe some of you will appreciate the chocolate bar of a paper wasp digging through a cocoa plantation.
The fact that scientists have yet to discover something so fundamental about vertebrate biology proves that “we need to know more about the biology of every species on Earth.” says Wake. “As we face climate change and habitat modification, we need to know what we are doing to our ecosystems, our support base.” and in the process, they have become an inevitable part of the delicate web that supports us all.
