These spiders are killed with vomiting

WWhen an undesirable victim stumbles in the spider network, the host Angeid usually welcomes the unhappy creature in his home by wrapping it in silk and penetrates it with ticks full of poison. In most cases, this poison is completely sufficient for paralysis, and sometimes kills prey. But for the insects that are discovered by rare spiders of uloboridae, the toxic fangs that must be interested in them. This is what is brewing this spiders’ courage.

“I found this reference to this same old paper saying that this family of spiders was not eligible and I was like what? Wait again. I thought all spiders were toxic,” says Julia Zancouli, an evolutionary biologist at the University of Lausanne. “So, then I started drilling.”

I stumbled on a drawing in the 1931 sheet, which showed that the heads of these spiders do not contain the poison glands that most spider types do. “But this was the only data that is really available,” she says. Therefore, I decided to check itself.

Zankouli and her colleagues turned their attention to one type in the Oluborida family Plumipes UloboraOr spider lace lace feather. Small spider and sensation, U. Perumip She wipes her prey hundreds of feet away from silk, and the most comprehensive winding of most spiders. After identifying its prey, the spider vomits all over the narrow package.

When Zankul and her colleagues dissect the heads of spiders, they found large muscles but there are no poison glands. When they looked closely at the fangs of spiders, they found that they lack a hole through which the poison could be expelled, providing more evidence that these spiders have lost their glands in the poison over the course of development.

After identifying its prey, the spider vomits all over the narrow package.

“As a science, there are no other groups of spiders that lost the glands of poison,” says Ronald Jenner, an evolutionary biologist at the Museum of Natural History at the Museum of Natural History, who did not participate in the study.

Scientists wanted to know if some other organs in the spider body had lost poison. So they looked for the active genes producing poison in their other parts, such as their reproductive organs, silk glands, and intestine. And here, it seems that the intestine contains genes that can symbolize poison -like materials.

To confirm this U. plumipesThe bowel secretions were already toxic, as they injected them into fruit flies. For comparison, they also injected flies with secretions of toxic spider -spider -spider -to -spider -spider. Both groups of secretions killed flies, indicating this U. plumipes Do not use toxic digestive fluids to go to kill, but these bowel secretions are common in spiders on a larger scale. In other words, it is possible that the poison used by other spiders did not migrate to the intestine, but rather U. plumipes I learned to use the intestinal secretions present in a new way. Scientists recently published their results in BMC Biology.

“The poison system is expensive … it costs metabolic energy to make poison and maintain this system,” says Jenner. “Therefore, in these spiders, losing the poison system means that they will have to develop a different way to fail prey.”

The secret of paralysis U. plumipes It lies in the wide silk cover that it works on and widespread fluid. Jenner says the spider is making “borrito” from its prey. Then the toxic digestive fluids are renewed on the entire beam, which kills the prey and then continues to solve its tissues. “The spider takes only liquid food so that they can break the digestive system broth caused by the fall of the digestive system,” says Jenner.

Spiders usually only throw toxins specifically in the wounds of the sting, so that if the poison is already killing the prey, then vomiting will. “It is a preserved feature that it has such strong digestive fluids, but the idea is that these unavoidable spiders have reinforced them for use of predation,” says Zancolli.

Why UloBoridae A family of spiders as a whole lost the glands in its heads, Jenner believes that this is no longer the need for poison in the prey. “I think they have become a silk borrotu maker who no longer need poison for paralysis,” he says. Some marine snakes have evolved along a similar The path, and the loss of all the organs participating in prey to poisoning at a time when they started feeding on fish eggs, which do not require picking or paralysis.

As a next step in the research, Jenner believes that scientists should look at the expression of key toxin genes or poison through the evolutionary spiders tree, as well as through other helix elements. “It was very interesting to know the number of toxins expressed in the intestine.” U. plumbiesJenner says. But are these toxins in other spiders as well?

Either way, over time, spiders seem to have developed a number of ways to enjoy lunch.

The leading image: Netha Hussein / Wikimedia Comong

• Rohini Supmanam

  Spread on August 12, 2025

  Rohini Supmanamam is a biologist who turned into a scientific journalist. She loves to write about interesting creatures on our planet. SubrahManyam has a PhD from the National Center for Biological Sciences at the Tata Institute for Basic Research in India. Follow it on X (Twitter previously) Rohsubb On LinkedInAnd see its wallet here.