Richard L. Lindroth, University of Wisconsin-Madison and Patricia C. Fernandez, Universidad de Buenos Aires

When we walked with a colleague into an aspen forest near Madison, Wisconsin, in the early spring of 2021, we expected to finalize our plans for a research project on several species of insects that live and feed on the trees. Instead, we found a forest laden with fuzzy, brown egg masses.

These masses, belonging to an invasive species known as the spongy moth, brought our plans to a screeching stop. We knew that within weeks, hungry spongy moth caterpillars would strip the forest bare.

We are chemical ecologists interested in how plant chemistry influences the interactions between plants and plant-feeding insects. As seasoned scientists, we’ve seen that good science stories sometimes end up nowhere near where the researchers first anticipated. This is one of those stories. And like many good stories, it incorporates villains, beauty, poison and death.

After an initial period of distressed hand-wringing about the fate of our aspen forest, we pivoted our research plans. We decided to address how defoliation – another word for leaf consumption – by an invasive species might alter the chemical composition of plants, to the detriment of native species.

All plants produce defense compounds to fend off herbivores, like insects, that try to eat them. These defenses include well-known chemicals like tannins, caffeine and cyanide. In turn, insects have evolved adaptations to these chemical defenses tailored to the particular species that they feed on.

The results from this study surprised even us and were published in September 2023 in the journal Ecology and Evolution.

The ecological players

Quaking aspen (Populus tremuloides) is the most widespread tree species in North America.

As a keystone species, aspen provides food and shelter for many forest organisms. Without these trees, forests across much of North America would look very different. Aspen has been ecologically successful in part because of its unique chemistry. It produces a class of defense compounds called salicinoids. Under most conditions, these defenses keep herbivores from fully defoliating the trees.

Invasive spongy moths (Lymantria dispar) are the most destructive defoliators of broadleaf forests in North America. Aspen is a favored food plant of spongy moths, which feed on expanding leaves in early summer. At high population densities, spongy moths can defoliate extensive areas of forest.

This spongy moth-induced carnage does not bode well for other insects that depend on aspen for food, such as the native silk moth Anthereae polyphemus, which feeds on aspen from mid- to late summer.

A natural experiment

From May through June 2021, spongy moth caterpillars ate nearly every green leaf in our aspen forest.

By early July, however, the trees grew another full set of leaves. A second aspen forest of the same age, located 4 miles (6 kilometers) away, experienced no defoliation.

This combination of damaged and undamaged forests provided the perfect conditions for what scientists call a natural experiment. The undamaged forests served as an experimental control that we could compare with the damaged forest to evaluate the consequences of spongy moth defoliation for insects that feed in late summer.

We collected leaves from both forests in late summer and analyzed them for levels of salicinoids.

We also fed the native polyphemus caterpillars leaves from either the defoliated or control forest to see how the defense compounds might influence their ability to live and grow.

We found that after defoliation by spongy moths, aspen trees grew a second set of leaves with much higher levels of salicinoids – an average of 8.4 times higher. In contrast, the control forest had leaves with far lower salicinoid levels, typical of aspen in late summer.

The high levels of defense compounds in the defoliated forest caused serious damage to the native silk moth caterpillars. Few caterpillars survived when fed leaves from the previously defoliated forest. Those that did survive had stunted growth.

Ecological implications

Our research showed for the first time how an invasive species can harm a native species by making their shared food resource far more toxic. And this type of ecological dynamic is likely not restricted to just aspen and silk moth caterpillars.

Over 100 different species of insects and mammals feed on aspen, and our earlier research has shown that high levels of salicinoids are harmful to many of them. Other tree species, like oaks, also produce more defense compounds after spongy moth defoliation, which could affect native herbivores.

Insects are critically important for the functioning and flourishing of all terrestrial ecosystems. But scientists have seen their numbers and diversity decline worldwide, a phenomenon called the insect apocalypse.

The causes of these declines are many, varied and far from completely known. Research like this is helping to fill that gap. Plant toxin-mediated indirect effects of invasive species appear to be yet one more cut in the death by a thousand cuts experienced by insects worldwide.

Finally, our story is one of science in action. Scientists cannot fully anticipate how natural events may disrupt the best-laid research plans, especially for field projects. Floods, droughts, tornadoes, lightning strikes, insect outbreaks – our research groups have experienced them all.

Occasionally, though, researchers can counter these challenges with creative ingenuity and scientific adaptability. And those can lead to surprising breakthroughs in our understanding of this extraordinary world.

Richard L. LindrothUniversity of Wisconsin-Madison and Patricia C. Fernandez, Professor of Agronomy and CONICET Scientist, Universidad de Buenos Aires

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

Kimberly Baker, Clemson University

With rising rates of obesity in the U.S. and increasing attention being paid to the health harms of processed foods, it’s clear that far more could be done to help consumers make healthy food choices.

A bill known as the TRUTH in Labeling Act has been sitting before Congress since late 2023. If passed, it would require U.S. food manufacturers to add a second nutrition label to the front of product packages, in addition to the ones currently found on the back or side panel. It would also require the label to highlight any potentially unhealthy ingredients in the product, such as the amount of sugar, sodium and saturated fat it contains.

The proposed legislation would provide consumers with a standardized, easy-to-read and quick way to decide whether a product is a healthy choice. Should the bill, which is still in committee, become law, the front-of-package label would be regulated by the U.S. Food and Drug Administration.

The current nutrition facts label, typically featuring more detailed nutritional information and found on a product’s side panel, would remain unchanged.

As a food safety extension specialist who works with farmers, entrepreneurs, manufacturers and the government to help bring healthy food to shoppers, I believe that consistent front-of-package labeling would greatly benefit consumers by offering a straightforward way to compare multiple products, helping them make more informed choices.

Even if passed, it will take time for the FDA to interpret the law and standardize the design and format. And it might be years before all food manufacturers are required to use the new label. In the meantime, more than 175 million Americans are overweight or obese, and with each passing day, that number grows.

Why the change?

The newly proposed legislation is the latest effort by lawmakers to educate the public about smart food choices. Congress began requiring standardized nutrition labels on food packages through the Nutrition Labeling and Education Act of 1990.

But in the 34 years since that first label appeared, the obesity rate has more than tripled; 40% of Americans are now obese. Another 31% are overweight, and diet-related chronic illnesses, including heart disease, stroke, cancer, hypertension and Type 2 diabetes are rampant. About 60% of U.S. adults – 130 million people – have at least one of these chronic illnesses.

All of these diseases are associated with consuming too much sugar, sodium or saturated fat – three key ingredients the front label will focus on.

Labels help shoppers make better choices

There’s another reason to require a second, easy-to-notice, easy-to-comprehend label. Only about 40% of Americans frequently read the existing nutrition facts label; some shoppers say they don’t understand it. A simpler label with a more direct message might help those consumers. In fact, some studies suggest front-of-package labels do assist shoppers in making smart choices.

Research shows that those who frequently read the current label tend to have healthier diets than those who don’t. For example, frequent readers are almost four times more likely than rare readers to meet the recommended daily fiber intake.

Now the bad news: Even the frequent readers met their fiber goals only about 13% of the time. That isn’t good, but it’s an improvement over the rare readers, who meet their goals a paltry 3.7% of the time.

For the record, the daily recommendation for fiber is 25 grams for women and 38 for men under 50; its slightly less for those over 50.

Some foods still exempt

It’s possible you’ve already seen some front-of-package nutritional labels on food products. But these labels are not regulated by the government. Known as the “facts-up-front” labeling system, it’s strictly voluntary and a choice of the individual food manufacturer, with label designs and formats provided by the Consumer Brands Association, a trade association representing the food industry. Only a small number of manufacturers have chosen to put these labels on their products.

That said, more research is needed to know how long-term behavior may change due to front-of-package labeling. But at least one food safety advocacy organization, while supportive of front-of-package labels, says the trade association’s facts-up-front system is less than optimal.

Even if the TRUTH in Labeling Act passes as currently written, some foods could remain exempt from the nutritional label requirement, including fish, coffee, tea and spices.

There is one caveat, however. If any product makes a nutritional or health claim on its package – including those that are normally exempt – then a nutrition facts label must be on it.

Kimberly Baker, Food Systems and Safety Program Team Director, Clemson University

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

Ted Spiker, University of Florida and Kevin W. Farmer, University of Florida

Tommy John pitched in the big leagues from 1963 to 1989 and won 288 games. Only 25 MLB pitchers have won more.

But check out his 27 years of statistics, and you’ll see one year is blank: 1975. That’s because in the fall of 1974, John underwent surgery for a ligament tear in his elbow, an injury once considered career-ending.

John was the first pitcher to return to action after suffering such an injury. In fact, John won more games after the surgery than before – and the procedure that repaired his arm is now named after him.

John went under the knife 50 years ago. Since then, Tommy John elbow reconstruction surgery has changed the game and the people who play it, from Little Leaguers to the pros.

How elbow ligaments tear

The ulnar collateral ligament, or UCL, is a band of fibrous tissue connecting two bones – the humerus in the upper arm and the ulna in the forearm on the inside of the elbow. If you didn’t have that ligament, there would be a gap between the two bones.

This ligament plays a critical role for athletes who throw, such as football quarterbacks and baseball pitchers, because it serves as an anatomical bridge. The UCL transmits the force of the throw from the shoulder to the hand as the ball is released.

But here’s the problem: The force on the elbow generated by pitching a baseball, especially from today’s high-velocity pitchers, exceeds the strength of the ligament.

Poor mechanics and other factors stress the ligament to the point where it can tear, thus causing the need for repair. To replace the torn tissue, the surgeon typically takes a relatively unused tendon from the pitcher’s forearm or hamstring.

Arms brought back to life

Before this surgery, a tear of the UCL ended many major league pitching careers.

Case in point: Sandy Koufax, the Los Angeles Dodgers pitcher and Hall of Famer, retired in 1966 because of severe elbow pain. Koufax was only 30 years old and at the zenith of his career. Frank Jobe, the doctor who performed the first Tommy John surgery and the Dodgers’ team physician at the time, said the procedure could have been called Sandy Koufax surgery had he developed the idea earlier.

Returning to play after Tommy John surgery is not without difficulties, and recovery takes a long time; John took close to two years before he could pitch again. Although today‘s surgery is much less invasive, recovery takes about a year.

About 80% of pitchers successfully return to playing after the surgery. But sometimes the repair doesn’t last forever, and about 30% of pitchers with repaired elbows undergo a second surgery.

A surge in surgeries

Since Tommy John, it’s estimated that nearly 2,500 professional baseball players have undergone the surgery, and the number of overall procedures increases about 9% a year.

One-third of current Major League Baseball pitchers had Tommy John surgery at some point. Shohei Ohtani, the Dodgers’ two-way superstar, had the procedure in 2023. While Ohtani returned to batting in 2024, he’s not expected to pitch until 2025.

There are several reasons why the number of surgeries have increased. First is the addition of a pitch clock in 2023, which works like a shot clock in basketball – pitchers must throw their next pitch within a certain time frame.

Pitchers also throw harder today than they did a half-century ago; the average velocity of pitches has increased about 4 miles per hour in the past 20 years. But pitchers who throw at higher velocities – particularly at speeds exceeding 100 miles per hour – are more likely to suffer this injury.

The rise of the sweeper pitch has also made an impact. This high-velocity breaking ball has been blamed for stressing the UCL.

Young arms carry heavier loads

Today, more than half of Tommy John surgeries are performed on kids ages 15 to 19 – essentially, teenagers who are high school or college athletes.

This is happening because youth sports have changed dramatically over the decades. It is now a US$15 billion business. Between school leagues, travel ball, all-star teams and showcases, young athletes play more often; in warmer parts of the country, they go year-round. Because many of them play for different teams and different coaches, nobody is monitoring overall pitch counts.

That, along with the relentless focus on one sport at an early age, means excessive stress on the elbow. Studies show athletes who play more than one sport actually have reduced injury rates.

The Pitch Smart program, sponsored by Major League Baseball and USA Baseball, offers resources to coaches and parents to help young athletes reduce the risk of injury. But adherence to the program is strictly voluntary. A 2021 study shows 90% of surveyed teams are not complying with Pitch Smart guidelines. Many youngsters are throwing too many pitches per day and not getting enough rest between games. Either parents and coaches are not aware of the Pitch Smart recommendations or they are simply ignoring them.

Indeed, there are parents who want their children to have the surgery prior to a possible injury because they believe that using the procedure as a preventive measure will make the elbow stronger and resistant to future tears. This, however, is a myth.

Tommy John, now 81, laments that the surgery that saved his career has become a routine procedure for children whose bodies are still developing. With teenagers now the clientele for the majority of these surgeries, John has called for a return to the youth sports of the past, a time when kids played not so much for the promise of fame, riches or scholarships but simply for the fun of it.

Admittedly, there’s little profit in that. But as more and more kids go under the knife, maybe parents and coaches will finally start to listen.

Ted Spiker, Professor of Journalism, University of Florida and Kevin W. Farmer, Professor of Orthopaedics and Sports Medicine, University of Florida

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