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Clothes moths: Why I admire these persistent, destructive, difficult-to-eradicate and dull-looking pests

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Clothes moths: Why I admire these persistent, destructive, difficult-to-eradicate and dull-looking pests

Tineola bisselliella can survive on as little as a hairball and some vitamin B.
Olaf Leillinger/Wikimedia Commons, CC BY-SA

Isabel Novick, Boston University

Every day, I into the lab to check the moth jar. The jar, which previously housed a liter of honey, now contains a multitude of small golden moths and their wriggly caterpillar offspring.

smiling woman holds a liter-size jar with scrunched up knitting in it
The author in the lab with her prized moth jar.
Isabel Novick, CC BY-ND

The founding population came from within my house – pests that fervently fed on my sweaters, rugs and horsehair plaster. When they emerge from my walls in the evenings, I chase them with zeal and catch them in jam jars. “Moth!” I shout, jumping up from the couch, knocking over whatever is in front of me. In the lab, I feed them clippings of a mohair sweater that shrank in the wash, which I soak in brewer's yeast.

I'm a doctoral candidate studying the evolutionary relationships within the moth Tineidae. I'm interested in how webbing clothes moths, Tineola bisselliella, have dispersed so widely and colonized our homes so readily. I am using a population genetics approach, examining the DNA of isolated populations of moths from all over the world. They eat crazy stuff. They mostly indoors. How did this happen?

Resourceful, vigorous, tanklike eating machines

Webbing clothes moths are part of a distinctive, primordial lineage called the fungus moth family. These guys emerged long before more well-known species like silk moths. If you're unlucky, you are already aware of the destruction they can wreak on sweaters, rugs and upholstery. But you many not realize how fascinating Tineidae are.

little worms on the surface of a knitted material
Tineola bisselliella larvae living it up on a scrap of sweater in the lab.
Isabel Novick, CC BY-ND

These moths can eat hair, skin and feathers, all of which comprise a protein called keratin. Keratin – the main ingredient in nails, hoofs and horns – is notoriously tough to digest. Biologists still aren't sure how clothes moths can metabolize keratin, and this is something I aim to address in my research. One study posits that they harbor a microorganism in their gut that uses digestive enzymes to break down keratin for them.

However mysterious the may be, their nutritional needs can be met with as little as a hairball and some vitamin B, which they can glean from sweat, pee and food stains. Not only that, but research suggests these moths somehow produce water as a byproduct of digesting keratin, so they can happily survive within the dry recesses of your home.

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Incredibly, webbing clothes moths can safely digest poisonous heavy metals like arsenic, mercury and lead. They can easily chew through soft plastics and metabolize synthetic fabrics. They have been known to feast on mummified human remains and have even been a recognizable pest long enough to be mentioned in the Bible. They are so economically destructive that by the 1990s they were causing up to US$1 billion in damage per year in the U.S. alone.

This pest insect, over time, has hitchhiked all over the world. It can now be found from Australia to Chile, from Nigeria to Canada. The current hypothesis is that these moths originated in Africa and expanded their range by hitchhiking on 19th-century ships.

Scientists consider webbing clothes moths synanthropes: organisms that benefit from, and have adapted to, human spaces, much like pigeons or bedbugs. They have taken this to an extreme and are now mostly found indoors.

color drawing of an insect with long antennae and folded wings
These moths aren't particularly pleasing to the human eye.
Steve Roberts/De Agostini Picture Library via Getty Images

Researchers are still not sure what evolutionary adaptations have these moths to colonize, and ultimately depend upon, human environments. However, it seems likely to me that their global domination is associated with their diet. Webbing clothes moths are known as facultative keratinophages, which means they can choose to eat and digest keratin, but it's not a required part of their diet. This kind of nutritional flexibility is common to other well-known synanthropic species – is there anything a raccoon won't eat? – and may be fundamental to the moths' successful global dispersal.

Moth genes from around the world

To study the differences between populations of webbing clothes moths around the world, I am analyzing a type of genomic data made from sequencing “ultraconserved elements.” This technique targets specific genes that all moth species share, called orthologs, and compares the variable genetic regions on both sides of the conserved sequence. This data tells researchers like me how distantly related the clothes moths in, say, Australia are to clothes moths in Hawaii.

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about a dozen small dead moths stuck to sticky cardboard
This trap came back with plenty of moths that unwittingly donated themselves to science.
Isabel Novick, CC BY-ND

To that end, I've spent the past two years internationally shipping pheromone-baited moth traps to interested volunteers. They set up the traps in their closets or storage rooms. After two months, I ask whether they've caught anything, request a of the trap and have them ship it back to me.

People generally want to because they hope my research will yield better methods of moth eradication. Ultimately, it may, but I'm primarily interested in appreciating these organisms from an evolutionary perspective.

So far, I have received over 600 moths. But many of my correspondents don't catch anything, or catch the wrong thing. Sometimes the trap gets thrown out with the . Sometimes I send a trap and never hear from the recipient again. It can be a frustrating process. I end up spending hundreds of dollars and sifting through hundreds of moths, most of them other tineids or pantry moths, looking for the flash of dusty golden wings.

I spend a lot of my time in the lab extracting moth DNA and a lot of time on my computer analyzing it. Ideally, this research will yield a more comprehensive picture of how moths in this family are related to one another, and clarify whether clothes moths from around the world are actually the species we think they are. If these moths are experiencing sexual isolation, we might be using the wrong methods to control them depending on their location.

pale moth with dark eye
Tineola bisselliella moth, ready for its close-up through the microscope.
Isabel Novick, CC BY-ND

Appreciation for a pest

Even though clothes moths can destroy your wardrobe or devour priceless objects like taxidermy, oriental carpets and upholstered furniture in museum collections, I can't help but admire them.

They are not intentionally pests; they are innovative, cunning and endlessly capable. Their ability to capitalize on unfilled niches has allowed them to spread far and wide throughout homes everywhere. They're not chomping through your drapes with malicious intent; they're operating exactly as they evolved to, in a way that has worked to their advantage for thousands of years. The reasons people dislike them – being persistent, destructive and difficult to eradicate, not to mention dull-colored – are the reasons they've been able to survive and thrive so successfully for so long.

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I gently urge you to consider their efficiency and determination as a sort of evolutionary elegance. How incredible is it for something to have evolved to eat the inedible, to occupy the uninhabitable and to overcome every evolutionary obstacle in its way? Of course, that doesn't mean their can't be devastating, or that battling these moths doesn't stink. But, from an evolutionary standpoint, the webbing clothes moth should inspire wonder instead of disgust, awe instead of frustration, and instead of exasperation, admiration.The Conversation

Isabel Novick, Doctoral Candidate in Ecology, Behavior and Evolution, Boston University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Conversation

Animal behavior research is getting better at keeping observer bias from sneaking in – but there’s still room to improve

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theconversation.com – Todd M. Freeberg, Professor and Associate Head of Psychology, University of Tennessee – 2024-05-03 07:16:49

What you expect can influence what you think you see.

Auscape/Universal Images Group via Getty Images

Todd M. Freeberg, University of Tennessee

Animal behavior research relies on careful observation of animals. Researchers might spend months in a jungle habitat watching tropical birds mate and raise their young. They might track the rates of physical contact in cattle herds of different densities. Or they could record the sounds whales make as they migrate through the ocean.

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Animal behavior research can fundamental insights into the natural processes that affect ecosystems around the globe, as well as into our own human minds and behavior.

I study animal behavior – and also the research reported by scientists in my field. One of the challenges of this kind of science is making sure our own assumptions don't influence what we think we see in animal subjects. Like all people, how scientists see the world is shaped by biases and expectations, which can affect how data is recorded and reported. For instance, scientists who in a society with strict gender roles for women and might interpret things they see animals doing as reflecting those same divisions.

The scientific corrects for such mistakes over time, but scientists have quicker methods at their disposal to minimize potential observer bias. Animal behavior scientists haven't always used these methods – but that's changing. A new study confirms that, over the past decade, studies increasingly adhere to the rigorous best practices that can minimize potential biases in animal behavior research.

Black and white photo of a horse with a man and a small table between them displaying three upright cards.

Adding up?

Karl Krall/Wikimedia Commons

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Biases and self-fulfilling prophecies

A German horse named Clever Hans is widely known in the history of animal behavior as a classic example of unconscious bias leading to a false result.

Around the turn of the 20th century, Clever Hans was purported to be able to do math. For example, in response to his owner's prompt “3 + 5,” Clever Hans would tap his hoof eight times. His owner would then reward him with his favorite vegetables. Initial observers reported that the horse's abilities were legitimate and that his owner was not being deceptive.

However, careful analysis by a young scientist named Oskar Pfungst revealed that if the horse could not see his owner, he couldn't answer correctly. So while Clever Hans was not good at math, he was incredibly good at observing his owner's subtle and unconscious cues that gave the math answers away.

In the 1960s, researchers asked human study participants to code the learning ability of rats. Participants were told their rats had been artificially selected over many generations to be either “bright” or “dull” learners. Over several weeks, the participants ran their rats through eight different learning experiments.

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In seven out of the eight experiments, the human participants ranked the “bright” rats as being better learners than the “dull” rats when, in reality, the researchers had randomly picked rats from their breeding colony. Bias led the human participants to see what they thought they should see.

Eliminating bias

Given the clear potential for human biases to skew scientific results, textbooks on animal behavior research methods from the 1980s onward have implored researchers to verify their work using at least one of two commonsense methods.

One is making sure the researcher observing the behavior does not know if the subject from one study group or the other. For example, a researcher would measure a cricket's behavior without knowing if it came from the experimental or control group.

The other best practice is utilizing a second researcher, who has fresh eyes and no knowledge of the data, to observe the behavior and code the data. For example, while analyzing a file, I count chickadees taking seeds from a feeder 15 times. Later, a second independent observer counts the same number.

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Yet these methods to minimize possible biases are often not employed by researchers in animal behavior, perhaps because these best practices take more time and effort.

In 2012, my colleagues and I reviewed nearly 1,000 articles published in five leading animal behavior journals between 1970 and 2010 to see how many reported these methods to minimize potential bias. Less than 10% did so. By contrast, the journal Infancy, which focuses on human infant behavior, was far more rigorous: Over 80% of its articles reported using methods to avoid bias.

It's a problem not just confined to my field. A 2015 of published articles in the sciences found that blind protocols are uncommon. It also found that studies using blind methods detected smaller differences between the key groups being observed to studies that didn't use blind methods, suggesting potential biases led to more notable results.

In the years after we published our article, it was cited regularly and we wondered if there had been any improvement in the field. So, we recently reviewed 40 articles from each of the same five journals for the year 2020.

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We found the rate of papers that reported controlling for bias improved in all five journals, from under 10% in our 2012 article to just over 50% in our new review. These rates of still lag behind the journal Infancy, however, which was 95% in 2020.

All in all, things are looking up, but the animal behavior field can still do better. Practically, with increasingly more portable and affordable audio and video recording technology, it's getting easier to carry out methods that minimize potential biases. The more the field of animal behavior sticks with these best practices, the stronger the foundation of knowledge and public trust in this science will become.The Conversation

Todd M. Freeberg, Professor and Associate Head of Psychology, University of Tennessee

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Boeing’s Starliner is about to launch − if successful, the test represents an important milestone for commercial spaceflight

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theconversation.com – Wendy Whitman Cobb, Professor of Strategy and Security Studies, Air – 2024-05-02 07:24:25

Boeing's Starliner spacecraft on approach to the International Station during an uncrewed test in 2022.

Bob Hines/NASA

Wendy Whitman Cobb, Air University

If all goes well late on May 6, 2024, NASA astronauts Butch Wilmore and Suni Williams will blast off into space on Boeing's Starliner spacecraft. Launching from the Kennedy Space Center, this last crucial test for Starliner will test out the new spacecraft and take the pair to the International Space Station for about a week.

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Part of NASA's commercial crew program, this long-delayed mission will represent the vehicle's first crewed launch. If successful, it will give NASA – and in the future, space tourists – more options for getting to low Earth orbit.

Two people wearing blue jumpsuits hug in front of a plane.

Suni Williams, right, and Butch Wilmore, the two astronauts who will crew the Starliner test.

AP Photo/Terry Renna

From my perspective as a space policy expert, Starliner's launch represents another significant milestone in the development of the commercial space industry. But the mission's troubled history also shows just how difficult the path to space can be, even for an experienced company like Boeing.

Origins and development

Following the retirement of NASA's space shuttle in 2011, NASA invited commercial space companies to the agency transport cargo and crew to the International Space Station.

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In 2014, NASA selected Boeing and SpaceX to build their respective crew vehicles: Starliner and Dragon.

Boeing's vehicle, Starliner, was built to carry up to seven crew members to and from low Earth orbit. For NASA missions to the International Space Station, it will carry up to four at a time, and it's designed to remain docked to the station for up to seven months. At 15 feet, the capsule where the crew will sit is slightly bigger than an Apollo command module or a SpaceX Dragon.

Boeing designed Starliner to be partially reusable to reduce the cost of getting to space. Though the Atlas V rocket it will take to space and the service module that supports the craft are both expendable, Starliner's crew capsule can be reused up to 10 times, with a six-month turnaround. Boeing has built two flightworthy Starliners to date.

A conical vehicle sitting on a flat vehicle.

The Starliner capsule in transit.

AP Photo/John Raoux

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Starliner's development has with setbacks. Though Boeing received US$4.2 billion from NASA, compared with $2.6 billion for SpaceX, Boeing spent more than $1.5 billion extra in developing the spacecraft.

On Starliner's first uncrewed test flight in 2019, a series of software and hardware failures prevented it from getting to its planned orbit as well as docking with the International Space Station. After testing out some of its , it landed successfully at White Sands Missile Range in New Mexico.

In 2022, after identifying and making more than 80 fixes, Starliner conducted a second uncrewed test flight. This time, the vehicle did successfully dock with the International Space Station and landed six days later in New Mexico.

The inside of a Starliner a few astronauts. Crew members first trained for the launch in a simulator.

Still, Boeing delayed the first crewed launch for Starliner from 2023 to 2024 because of additional problems. One involved Starliner's parachutes, which help to slow the vehicle as it returns to Earth. Tests found that some links in those parachute lines were weaker than expected, which could have caused them to break. A second problem was the use of flammable tape that could pose a fire hazard.

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A major question stemming from these delays concerns why Starliner has been so difficult to develop. For one, NASA officials admitted that it did not provide as much oversight for Starliner as it did for SpaceX's Dragon because of the agency's familiarity with Boeing.

And Boeing has experienced several problems recently, most visibly with the safety of its airplanes. Astronaut Butch Wilmore has denied that Starliner's problems reflect these troubles.

But several of Boeing's other space activities beyond Starliner have also experienced mechanical failures and budget pressure, including the Space Launch System. This system is planned to be the main rocket for NASA's Artemis program, which plans to return humans to the Moon for the first time since the Apollo era.

Significance for NASA and commercial spaceflight

Given these difficulties, Starliner's success will be important for Boeing's future space efforts. Even if SpaceX's Dragon can successfully transport NASA astronauts to the International Space Station, the agency needs a backup. And that's where Starliner in.

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Following the Challenger explosion in 1986 and the Columbia shuttle accident in 2003, NASA retired the space shuttle in 2011. The agency was left with few options to get astronauts to and from space. Having a second commercial crew vehicle provider means that NASA will not have to depend on one company or vehicle for space launches as it previously had to.

Perhaps more importantly, if Starliner is successful, it could compete with SpaceX. Though there's no crushing demand for space right now, and Boeing has no plans to market Starliner for tourism anytime soon, competition is important in any market to down costs and increase innovation.

More such competition is likely coming. Sierra Space's Dream Chaser is planning to launch later this year to transport cargo for NASA to the International Space Station. A crewed version of the space plane is also being developed for the next round of NASA's commercial crew program. Blue Origin is working with NASA in this latest round of commercial crew contracts and developing a lunar lander for the Artemis program.

A conical white spacecraft with two rectangular solar panels in space, with the Earth in the background.

SpaceX's dragon capsule.

NASA TV via AP

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Though SpaceX has made commercial spaceflight look relatively easy, Boeing's rocky experience with Starliner shows just how hard spaceflight continues to be, even for an experienced company.

Starliner is important not just for NASA and Boeing, but to demonstrate that more than one company can find success in the commercial space industry. A successful launch would also give NASA more confidence in the industry's ability to operations in Earth's orbit while the agency focuses on future missions to the Moon and beyond.The Conversation

Wendy Whitman Cobb, Professor of Strategy and Security Studies, Air University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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The Conversation

Brain cancer in children is notoriously hard to treat – a new mRNA cancer vaccine triggers an attack from within

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theconversation.com – Christina von Roemeling, Assistant Professor of Neurosurgery, University of Florida – 2024-05-01 10:01:09

How cancer vaccines are delivered into the body influences their effectiveness.

Liuhsihsiang/iStock via Getty Images Plus

Christina von Roemeling, University of Florida and John Ligon, University of Florida

Brain cancers remain among the most challenging tumors to treat. They often don't respond to traditional treatments because many chemotherapies are unable to penetrate the protective barrier around the brain. Other treatments like radiation and surgery can patients with lifelong debilitating side effects.

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As a result, brain cancer is the leading cause of cancer-related death in children. Brain tumors in frequently do not respond to treatments developed for adults, likely due to the fact that pediatric brain cancers are not as well-studied as adult brain cancers. There is an urgent need to develop new treatments specific to children.

We developed a new messenger-RNA, or mRNA, cancer vaccine, described in newly published research, that can deliver treatments more effectively in children who have brain cancer and teach their immune to fight back.

Close-up of child's hand with IV line placed held by adult's hand

Cancer treatments designed for adults may not necessarily work as well in children.

Virojt Changyencham/Moment via Getty Images

How do cancer vaccines work?

The immune system is a complex network of cells, tissues and organs whose primary function is to continuously surveil the body for threats posed by foreign invaders – pathogens that tissues and make you sick. It accomplishes this by recognizing antigens, or abnormal proteins or molecules, on pathogens. T cells that recognize these antigens seek out and destroy the pathogens.

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Your immune system also protects you from domestic threats like cancer. Over time, your cells sustain DNA damage from either internal or external stressors, leading to mutations. The proteins and molecules produced from mutated DNA look quite different from the ones cells typically produce, so your immune system can recognize them as antigens. Cancer develops when cells accumulate mutations that enable them to continue to grow and divide while simultaneously going undetected by the immune system.

In 1991, scientists identified the first tumor antigen, helping lay the framework for modern-day immunotherapy. Since then, researchers have identified many new tumor antigens, facilitating the of cancer vaccines. Broadly, cancer vaccines deliver tumor antigens into the body to teach the immune system to recognize and attack cancer cells that display those antigens. Although all cancer vaccines conceptually work very similarly, they each significantly vary in the way they are developed and the number and combination of antigens they carry.

Cancer vaccines the immune system differentiate between healthy cells and tumor cells.

One of the biggest differences among cancer vaccines is how they are created. Some vaccines use protein fragments, or peptides, of tumor antigens that are directly given to patients. Other vaccines use viruses reengineered to express cancer antigens. Even more complex are vaccines where a patient's own immune cells are collected and trained to recognize cancer antigens in a laboratory before being delivered back to the patient.

Currently, there is a lot of excitement and focus among researchers on developing mRNA-based cancer vaccines. Whereas DNA is the blueprint of which proteins to make, mRNA is a copy of the blueprint that tells cells how to build these proteins. Thus, researchers can use mRNA to create blueprint copies of potential antigens.

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mRNA cancer vaccines

The COVID-19 pandemic brought significant attention to the potential of using mRNA-based vaccines to stimulate the immune system and protection against the antigens they encode for. But researchers have been investigating the use of mRNA vaccines for treating various cancers since before the pandemic.

Our team of scientists in the Brain Tumor Immunotherapy Program at University of Florida has spent the past 10 years developing and optimizing mRNA vaccines to treat brain cancer.

Cancer vaccines have significant challenges. One key hurdle is that these vaccines may not always trigger a strong enough immune response to eradicate the cancer completely. Moreover, tumors are not made up of one type of cancer cell, but rather a complex mix of cancer cells that each harbors its own unique cocktail of mutations.

Our cancer vaccine seeks to address these issues in a number of ways.

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Diagram of lipid molecules formed a spherical shell around single-stranded mRNAs

Lipid nanoparticles can carry therapeutic mRNA into the body.

Buschmann et al. 2021/ Wikimedia Commons, CC BY-SA

First, we designed our vaccines by using the RNA of a patients' own cancer cells as a template for the mRNA inside our nanoparticles. We also packaged our cancer vaccine inside of nanoparticles made up of specialized lipids, or fat molecules. We maximized the amount of mRNA packaged within each nanoparticle by sandwiching them between lipid layers like the layers of an onion. In this way, we increase the likelihood that the mRNA molecules in our nanoparticles produce enough tumor antigens from that patient's cancer to activate an immune response.

Also, instead of injecting nanoparticles into the skin, muscle or directly into the tumor, as is commonly done for many therapeutic cancer vaccines, our mRNA nanoparticles are injected into the bloodstream. From there, they travel to organs throughout the body involved in the immune response to teach the body to fight against the cancer. By doing so, we've found that the immune system launches a near immediate and powerful response. Within six hours of receiving the vaccine, there is a significant increase in the amount of blood markers connected to immune activation.

Looking to the future

Our mRNA-based vaccines are currently undergoing early-phase clinical trials to treat real patients with brain cancer.

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We administered our mRNA-based vaccine to four adult patients with glioblastoma who had relapsed after previous treatment. All patients survived several months longer than the expected average survival at this advanced stage of illness. We expect to treat children with a type of brain tumor called pediatric high-grade glioma by the end of the year.

Importantly, mRNA vaccines can be developed to treat any kind of cancer, childhood brain tumors. Our Pediatric Cancer Immunotherapy Initiative focuses on developing new immune-based therapies for children afflicted with cancer. After developing an mRNA vaccine for glioma in chidren, we will expand to treat other kinds of pediatric brain cancers like medulloblastoma and potentially treat other kinds of cancers like skin cancer and bone cancer.

We are hopeful that mRNA-based vaccines may to more children being cured of their brain tumors.The Conversation

Christina von Roemeling, Assistant Professor of Neurosurgery, University of Florida and John Ligon, Assistant Professor of Hematology, University of Florida

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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