Tag Archives: Wasps

Just like bees, wasps are highly valuable insects, study finds

We have always had a rocky relationship with wasps. They are the sort of insects we love to hate. They’ve ruined a good number of picnics and disrupted us from enjoying pints in pub beer gardens. But wasps deserve much more credit, a group of researchers argue, as they provide key ecosystem services that we all rely on.

Image credit: Flickr / Jiri Zuna

United Kingdom researchers found that the reputation of wasps as irritating but pointless insects is far from fair. There’s a prejudice against them that is culturally embedded, rising from our ignorance about what wasps do in ecosystems and how that’s beneficial for us. They are crucial predators and pollinators, the authors argue.

“We value bees (which also sting) because they pollinate our crops and make honey. We go out of our way to rescue a bee from inside a window; but we don’t flinch as we slam a rolled-up magazine over a wasp in the same situation,” Seirian Sumner, co-author of the study, wrote in a commentary, summarizing the study’s findings.

Scientists try to define the value of natural resources to us in terms of their ecosystem services — the functions or goods provided by nature that support the quality of human life. Some are very familiar, such as the value of pollination services by bees, without which we would have to hand-pollinate our crops (and/or starve).

Certain insects are renowned for their contributions, but that’s not the case with wasps. Studies have shown that wasps eat a lot of insects, many of which could be agricultural pests. But nobody has calculated their efforts, for example the quantity of insect pests wasps remove from agricultural landscapes.

Sumner and her team looked at over 500 scientific papers on stinging wasps to understand how they contribute to ecosystems, and how this can help the economy, human health, and society. There are 100,000 known wasp species, but 70,000 are parasitic, which are stingless and quite well studied.

“Wasps are understudied relative to other insects like bees, so we are only now starting to properly understand the value and importance of their ecosystem services. We have reviewed the best evidence there is, and found that wasps could be just as valuable as other beloved insects like bees if only we gave them more of a chance,” Sumner said in a statement.

These are some of the ecosystem services provided by wasps, according to the study, which show we shouldn’t take this insect for granted:

Nature pest controllers

Over 30,000 species of wasps act as pest controllers, hunting a diversity of invertebrates from bugs and spiders to roaches. They regulate the populations of these organisms alongside other predators like mammals and amphibians. They can even match fluctuations in prey populations due to their short lives and fast reproduction rate.

As awareness expands over the detrimental effect of chemicals used in agriculture on wildlife, the researchers argue we have to look for more sustainable approaches. And this is where predatory wasps enter. Insects have a long history of being used as biocontrol agents of crop pests, with an overall value estimated at $417 billion.

Pollination services

Over 75% of our crops rely on insects for pollination, with pollination services estimated to be worth over $235 billion a year worldwide. While wasps hunt prey to feed their offspring, the adults are herbivores and visit flowers for carbohydrates in the form of sugar. Just like bees.

The researchers counted 164 plant species across six families that are completely reliant on wasps for pollination. Most of these are orchids that have evolved to mimic female wasp pheromones — some even look like the back end of a female wasp. There are no studies yet to estimate the value of wasps as pollinators.

Food and medicine

Wasps and many other insects are high in protein and essential amino acids. Pound for pound, they use less space or water and emit fewer greenhouse gases and ammonia than other livestock. That’s why the researchers suggest insects as food for humans as a possible avenue to sustainable food security. Over 2 billion people already consume insects in their diet.

But it’s not all about food. Wasps’ venom has plenty of benefits for human health, as it’s packed with antibiotics and antimicrobials. The venom has been of significant pharmacological interest lately due to the many biologically-active molecules it contains. Of recent interest is its potential in the treatment of cancer, for example.

The study was published in the journal Biological Reviews.

Microscopic wasps are being used to get rid of moths in a UK historic mansion

Without any visitors amid the pandemic, many of the historic buildings across the United Kingdom have been invaded by hundreds of moths – all chowing down on priceless carpets, tapestries, and art. Now, administrators at one of the affected buildings hope to fight back by deploying a large number of microscopic, parasitic wasps.

The Blickling Hall. Image credit: Wikipedia Commons

The pest control technique will be used in a few weeks at Blickling Hall in Norfolk, which is thought to be the birthplace of Henry VIII’s second wife Anne Boleyn. The property has a long list of treasures, such as a Peter The Great tapestry, given by Russia’s Catherine The Great to Blickling’s owner, and a state bed with the most complete 18th-century examples of a canopy and headcloth.

Blickling is one of the more than 500 historic castles, houses, parks, and monuments regularly maintained by UK National Trust. But the pandemic presented a new challenge for many of them. A recent survey of the properties found that the number of bugs had risen by 11% in 2020 compared with the previous year. Mold outbreaks were also reported due to a lack of activity to drive airflow.

Now, a multi-pronged trial at Blickling will use a microscopic parasitoid wasp, called Trichogramma evanescens, together with specially prepared moth pheromones to target the whole lifecycle of the moth. While both wasps and pheromones have been used separately against moths in the past, this is the first time the combination is tried out in a heritage site, according to the National Trust.

“It’s not like our tapestries are falling off the wall and our things are being munched to bits,” Hilary Jarvis, an assistant national conservator at the National Trust, told The New York Times. “It’s just that no damage is acceptable and it’s heartbreaking when you do find something,” she said. “We know they’re there and we’re not going to be complacent, and I can’t take the risk that we let those moths thrive.”

The wasp chosen for the experiment is a natural enemy of the clothes moth. It searches for moth eggs and lays its own inside, so that a wasp hatches instead of the moth larva. The wasp measures about 0.5 millimeters so it’s barely visible and it’s also not harmful to humans or animals. They will be housed in small dispensers, each with 2,400 wasps, and placed in drawers or open rooms.

Meanwhile, the pheromone tabs will disrupt the mating of adult moths. They will continuously spread female pheromones – chemicals released to attract males of the same species — to confuse male moths. This reduces their chance of finding a female mate. The tabs use electrostatic technology to physically transfer the pheromone onto the bodies of male moths, turning them into portable female pheromone dispensers.

“We are really hoping this pioneering approach will provide a practical and sustainable method that any of our properties can use to deal with serious infestations,” Jarvis told the BBC. “The lockdown has suited our resident bugs. The relative quiet, darkness, and absence of disruption from visitors and staff provided perfect conditions for larvae and adults alike from March onwards.”

The anti-moth campaign will begin early next month and continue through the rest of the year. Once their mission is complete, the wasps will eventually die and disappear into house dust. If the trial significantly reduces the moth population, Jarvis said it could be used in the other properties of the National Trust experiencing the same problem in the United Kingdom.

Buildings and roads around the world have been filling with animals that ventured into places where they couldn’t or wouldn’t before the pandemic. Bats nestled in the spaces between walls of newly empty buildings in the US, goats were seen running in streets in the UK, and coyotes roamed in San Francisco, for example. The UK’s moths are part of the same trend.

Wasps are effective pest controls, a new study shows

Although you may be terrified of them, common, social wasp species could help keep our crops pest-free, reports a new study.

A hornet queen.
Image credits David Hablützel.

The blue and black predators can act as solid pest control for at least two high-value crops: maize and sugarcane. While the experiment was carried out in Brazil, the team explains that wasps are found virtually all over the world and can easily be ‘recruited’ on small or large-scale farms to control a range of common pest insects.

The Buzz of victory

“There’s a global need for more sustainable methods to control agricultural pests, to reduce over-reliance on pesticides or imported pest controllers. Wasps are very common, but understudied, so here we’re providing important evidence of their economic value as pest controllers,” said the study’s lead author, Dr. Robin Southon from University College London’s (UCL) Centre for Biodiversity & Environmental Research.

The study was carried out in Brazil with the help of researchers at São Paulo State University and Universidade de São Paulo; the team explains that it is the first controlled experiment in semi-natural conditions on the subject, as it was performed on an outdoor research site. The maize crops used in the study were infested with fall armyworms, while the sugarcane crops were infested with sugarcane borers. As a pest control, the team used the social paper wasp, a hunting wasp common to the area.

All in all, the wasps seem to have been effective. Their presence reduced the pest populations and led to the crops suffering less damage. The team further found that even pests which already bored inside the plants (and weren’t present on their surfaces) were removed by the wasps.

The findings definitely suggest that the wasps have potential as pest control agents and could be used as part of a larger, integrated pest management mechanism. The team is especially excited for their use as wasps are native species and naturally part of many ecosystems today, which would make them a much more sustainable and environmentally-friendly alternative to today’s pesticides. Not only that, but the insects can also be a “cheap, accessible form of pest control, particularly helpful to small-scale or subsistence farmers in countries like Brazil, who could attract and encourage wasps to establish themselves,” according to co-author Professor Fabio Nascimento, who hosted the study at his labs in São Paulo State University.

The team plans to continue their research using larger, active agricultural fields. Wasps today are in decline across the world, similarly bees. The team notes that wasp loss can lead to a sharp increase in aphids, flies, and other species they prey on.

“This isn’t just about agriculture—this is about wasps in general and their role in regulating insect populations,” says Dr. Seirian Sumner (UCL Centre for Biodiversity & Environment Research), the study’s senior author. “Even your backyard garden could benefit from a more wasp-friendly attitude—instead of killing wasps and using pesticides on your plants, treat your local wasps as the helpful pest controllers they are.”

The paper “Social wasps are effective biocontrol agents of key lepidopteran crop pests” has been published in the journal Proceedings of the Royal Society B: Biological Sciences.

Researchers repurpose wasp venom peptides as antibiotics

The compounds can kill unwanted bacteria but are completely harmless to humans.

Finally, a use for wasps.

Few creatures are as hated as wasps. Although they do provide some environmental services, they’re often parasitic species, they’re nasty, and their sting can pack quite a punch. Unlike bees, their stingers don’t get lodged in the unfortunate victim, but even so, a wasp’s venom can cause great pain and irritation to humans.

Naturally, it’s also excellent at killing bacteria — the problem is that it also kills healthy, clean cells. Now, A team of MIT researchers managed to tweak the wasp venom so that it only kills bacteria, and leaves good cells alone.

“We’ve repurposed a toxic molecule into one that is a viable molecule to treat infections,” says Cesar de la Fuente-Nunez, an MIT postdoc. “By systematically analyzing the structure and function of these peptides, we’ve been able to tune their properties and activity.”

The key lies in a group of compounds called peptides. These are essentially a group of amino acids linked together to form a chain. They carry out important physiological functions, and in many ways, are similar to proteins. However, peptides are much smaller than proteins. They also tend to be less well defined in structure and scope than proteins.

Peptides in the wasps’ venom kill microbes by destroying their cell membranes — this happens because the peptides have a helix-type structure, with a right-hand spiral spin (which is known to strongly interact with cell membranes). The researchers isolated a venom peptide from a wasp called Polybia paulista, whose habitat ranges over several South American countries.

The peptide is small, containing only 12 amino acids, which allows researchers to experiment with it more easily.

“It’s a small enough peptide that you can try to mutate as many amino acid residues as possible to try to figure out how each building block is contributing to antimicrobial activity and toxicity,” de la Fuente-Nunez says.

A typical alpha-helical structure.

They tweaked a few dozen versions, measuring how each alteration affected the peptide’s properties, and then tested them against seven strains of bacteria and two of fungus, further correlating their structure and physiochemical properties (such as hydrophobicity and helicity) with their antimicrobial potency. After these observations, they designed several other versions, identifying the optimal percentages and structures of different amino acids so that they harm bacteria while leaving healthy tissue intact. Then, to test if the resulting peptides really were harmless, they tested their toxicity on human embryonic kidney cells grown in a lab dish.

The cells were infected with Pseudomonas aeruginosa — a common source of respiratory and urinary tract infections. They found that one peptide could completely clear the infection, eliminating it after only a few days.

“After four days, that compound can completely clear the infection, and that was quite surprising and exciting because we don’t typically see that with other experimental antimicrobials or other antibiotics that we’ve tested in the past with this particular mouse model,” de la Fuente-Nunez says.

In addition, researchers say a similar technique could be used in a wide array of situations.

“I do think some of the principles that we’ve learned here can be applicable to other similar peptides that are derived from nature,” he says. “Things like helicity and hydrophobicity are very important for a lot of these molecules, and some of the rules that we’ve learned here can definitely be extrapolated.”

This is not the first time peptides have been used to kill pathogens. The technique is particularly promising considering the worrying emergence of drug-resistant bacteria. Not only could this technology work as a new class of antibiotics, but it could also render pathogens incapable to adapt to it since adaptation processes usually take place at the cellular walls, and these peptides actually destroy the wall.

Due to their small size, peptides from wasp and scorpion venom are also being investigated as tools to ferry drugs to the brain, through the blood-brain barrier.

The paper was published in Nature Communications Biology.

Credit: Pixabay.

Most people hate wasps — but they deserve to be loved just as much as bees

Credit: Pixabay.

Credit: Pixabay.

As anyone who’s ever been to a picnic can attest, wasps can be extremely annoying. Not very surprisingly, a new study found that most people loathe wasps, whereas bees — which are closely related to wasps — are seen very positively.

The authors, however, stress that this cultural narrative isn’t helpful, nor accurate. Wasps play an important role in many ecosystems, which could easily collapse in their absence. As wasps face their own threats and challenges, it helps that the public is better informed about the insects’ ecological role.

Wasps are as ecologically useful as bees, scientists say

It’s easy to hate on wasps — their sting really hurts and they have a rather despicable appearance. For an unlucky few, the insects can pose a real life-threatening hazard if they experience an extreme immune system reaction to the venom and enter anaphylactic shock. Culturally-speaking, they’re often portrayed as pests that prey on the weak, whereas noble bees toil throughout the day, pollinate crops, and offer us riches. But the truth is wasps may be just as useful as bees, researchers at the University College London argue in a new study.

The researchers surveyed nearly 750 people from 46 countries about their perception of insects, bees and wasps included. The results were very clear: the vast majority of the public favors bees, which they see in a positive light, whereas wasps were despised. Bees were described with positive words such as “pollinate, honey flowers, buzz”, whereas wasps were associated with “sting, annoying, pain, dangerous”.

“The results show that wasps are indeed universally disliked by the public and moreover are unpopular research taxa among researchers,” the authors wrote in the journal Ecological Entomology. 

However, wasps don’t deserve their bad reputation. It’s a myth that wasps don’t pollinate — they actually do pollinate, albeit not as extensively as bees do. And because they are generalist pollinators, wasps can cover ground where bees can’t reach or where they’ve been eliminated (i.e. due to colony collapse disorder).

Credit: Pixabay.

The most important ecological role of wasps, however, is that of pest-controllers. There’s a great variety of wasps, totaling roughly 100,000 species. Some are wingless, some dig in the ground, but nearly all prey on or parasitize pest insects. Because their larvae only eat solid food, most of a wasp’s free time is spent foraging for food, which includes species that we consider pests: aphids and caterpillars that eat the plants we want to eat, or like to admire.

Where it not for their predatory behavior, countless species of insects would be left unchecked and allowed to breed to such a scale that they would overwhelm the ecosystem.

“People don’t realise how incredibly valuable they are,” Dr. Seirian Sumner of University College London, who led the research, told BBC News.

“Although you might think they are after your beer or jam sandwich – they are, in fact, much more interested in finding insect prey to take back to their nest to feed their lavae.”

This mismatch between the ecological value of wasps and their cultural misrepresentation can have negative consequences. According to the British researchers, the number of scientific papers on the ecological importance of bees outnumbers those on wasps by 40 to 1. So not only is their role and usefulness poorly communicated in the media and other cultural mediums, but they’re also understudied.

Like bees, wasps are declining in numbers due to climate change and loss of habitat. But the lack of research, essentially due to bad press, is stalling conservation efforts. The solution is a cultural shift, which has to begin with researchers who should be more inclined to study the insects.

“Positive action to promote research on wasps and to overhaul the public image of wasps via outreach and the media could help to reset the imbalance in appreciation of two of the world’s most ecologically important taxa. Cultural shifts to a more positive attitude towards wasps could be pivotal in working with these facets of natural capital, rather than against them,” the authors concluded.

Dominant wasps hand out breaks when workers are scarce, become horrible bosses when they’re plentiful

A new study has found that wasps create complex social structures around the supply and demand of labor. Dominant and worker wasps will often compete with one another to get the best deal for their investment — be it work or admission to the nest.

Ahh, the smell of waspitalism in the morning.
Image credits Skeeze / Pixabay.

If humans and wasps have something in common, is that we both like to work little but get paid big. The finding comes from a University of Sussex School of Life Sciences team, which analyzed how paper wasps apply the mechanisms of supply and demand. Their society is centered around a dominant class of breeder wasps and ‘helpers’ which raise their offspring in return for acceptance into the nest and the group. But the breeders don’t just lord over the helpers — the two classes have to engage in a willing trade to get the shelter, or the labor, they need.

And where there’s trade, there’s competition.

The wasp is right

The study was carried out in southern Spain over a three-month period, during which the team marked and genotyped 1500 paper wasps. They also recorded the social behavior in 43 separate nests along a cactus hedge.

Then they started to toy with the number of nesting spots and potential nesting partners around the hedge. When this number increased, the team observed that helper wasps performed less labor for their breeder. Dominant wasps also compete between themselves in a way, trying to give the helpers the best deal — by allowing them to slack off — so they don’t leave the nest.

“Market forces can clearly affect trade agreements in nature, as they can in human markets: with a larger number of trading partners available, you can negotiate better trade deals,” said lead author Dr Lena Grinsted,

But when the number went down, worker wasps didn’t have as many options to chose from, and the dominant wasps allowed for fewer benefits.

This would be the first time that supply and demand theory is shown to shape helping behavior in social insects. Previously, it was believed that only internal factors such as the number of available helpers or relatedness drives these behaviors. By showing that external factors (such as the availability of work from outside sources) also plays a part, the team’s observations allow us to better understand and predict insect behavior in the future.

“It is remarkable to discover that simply changing the wasps’ surrounding social environment has a clear effect on cooperative behaviour within groups,” Grinsted added.

“Our findings reveal intriguing parallels between wasp populations and our own business world: a bad deal is better than no deal, so when competition increases so does the risk that you have to accept a lower price for what you offer.”

So what about you? Do you stay loyal to the hive through good and bad, or will you buzz away to the best deal as soon as possible?

The full paper “Market forces influence helping behaviour in cooperatively breeding paper wasps” has been published in the journal Nature Communications.