Engineers develop self-healing muscle for robots

A University of Nebraska-Lincoln engineering team is another step closer to developing soft robotics and wearable systems that mimic the ability of human and plant skin to detect and self-heal injuries.

Engineer Eric Markvicka, along with graduate students Ethan Krings and Patrick McManigal, recently presented a paper at the IEEE International Conference on Robotics and Automation in Atlanta, Georgia, that sets forth a systems-level approach for a soft robotics technology that can identify damage from a puncture or extreme pressure, pinpoint its location and autonomously initiate self-repair.

The paper was among the 39 of 1,606 submissions selected as an ICRA 2025 Best Paper Award finalist. It was also a finalist for the Best Student Paper Award and in the mechanism and design category.

The team’s strategy may help overcome a longstanding problem in developing soft robotics systems that import nature-inspired design principles.

“In our community, there is a huge push toward replicating traditional rigid systems using soft materials, and a huge movement toward biomimicry,” said Markvicka, Robert F. and Myrna L. Krohn Assistant Professor of Biomedical Engineering. “While we’ve been able to create stretchable electronics and actuators that are soft and conformal, they often don’t mimic biology in their ability to respond to damage and then initiate self-repair.”

To fill that gap, his team developed an intelligent, self-healing artificial muscle featuring a multi-layer architecture that enables the system to identify and locate damage, then initiate a self-repair mechanism — all without external intervention.

“The human body and animals are amazing. We can get cut and bruised and get some pretty serious injuries. And in most cases, with very limited external applications of bandages and medications, we’re able to self-heal a lot of things,” Markvicka said. “If we could replicate that within synthetic systems, that would really transform the field and how we think about electronics and machines.”

The team’s “muscle” — or actuator, the part of a robot that converts energy into physical movement — has three layers. The bottom one — the damage detection layer — is a soft electronic skin composed of liquid metal microdroplets embedded in a silicone elastomer. That skin is adhered to the middle layer, the self-healing component, which is a stiff thermoplastic elastomer. On top is the actuation layer, which kick-starts the muscle’s motion when pressurized with water.

To begin the process, the team induces five monitoring currents across the bottom “skin” of the muscle, which is connected to a microcontroller and sensing circuit. Puncture or pressure damage to that layer triggers formation of an electrical network between the traces. The system recognizes this electrical footprint as evidence of damage and subsequently increases the current running through the newly formed electrical network.

This enables that network to function as a local Joule heater, converting the energy of the electric current into heat around the areas of damage. After a few minutes, this heat melts and reprocesses the middle thermoplastic layer, which seals the damage — effectively self-healing the wound.

The last step is resetting the system back to its original state by erasing the bottom layer’s electrical footprint of damage. To do this, Markvicka’s team is exploiting the effects of electromigration, a process in which an electrical current causes metal atoms to migrate. The phenomenon is traditionally viewed as a hindrance in metallic circuits because moving atoms deform and cause gaps in a circuit’s materials, leading to device failure and breakage.

In a major innovation, the researchers are using electromigration to solve a problem that has long plagued their efforts to create an autonomous, self-healing system: the seeming permanency of the damage-induced electrical networks in the bottom layer. Without the ability to reset the baseline monitoring traces, the system cannot complete more than one cycle of damage and repair.

It struck the researchers that electromigration — with its ability to physically separate metal ions and trigger open-circuit failure — might be the key to erasing the newly formed traces. The strategy worked: By further ramping up the current, the team can induce electromigration and thermal failure mechanisms that reset the damage detection network.

“Electromigration is generally seen as a huge negative,” Markvicka said. “It’s one of the bottlenecks that has prevented the miniaturization of electronics. We use it in a unique and really positive way here. Instead of trying to prevent it from happening, we are, for the first time, harnessing it to erase traces that we used to think were permanent.”

Autonomously self-healing technology has potential to revolutionize many industries. In agricultural states like Nebraska, it could be a boon for robotics systems that frequently encounter sharp objects like twigs, thorns, plastic and glass. It could also revolutionize wearable health monitoring devices that must withstand daily wear and tear.

The technology would also benefit society more broadly. Most consumer-based electronics have lifespans of only one or two years, contributing to billions of pounds of electronic waste each year. This waste contains toxins like lead and mercury, which threaten human and environmental health. Self-healing technology could help stem the tide.

“If we can begin to create materials that are able to passably and autonomously detect when damage has happened, and then initiate these self-repair mechanisms, it would really be transformative,” Markvicka said.

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New plant leaf aging factor found

Osaka Metropolitan University. “New plant leaf aging factor found.” ScienceDaily. ScienceDaily, 30 May 2025. <www.sciencedaily.com/releases/2025/05/250530124254.htm>.

Osaka Metropolitan University. (2025, May 30). New plant leaf aging factor found. ScienceDaily. Retrieved May 30, 2025 from www.sciencedaily.com/releases/2025/05/250530124254.htm

Osaka Metropolitan University. “New plant leaf aging factor found.” ScienceDaily. www.sciencedaily.com/releases/2025/05/250530124254.htm (accessed May 30, 2025).

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Mediterranean diet provides symptom relief for patients with IBS in pilot study

A pilot study from Michigan Medicine researchers found that the Mediterranean diet may provide symptom relief for people with irritable bowel syndrome.

Study participants were randomized into two groups, one following the Mediterranean diet and the other following the low FODMAP diet, a common restrictive diet for IBS.

In the Mediterranean diet group, 73% of the patients met the primary endpoint for symptom improvement, versus 81.8% in the low FODMAP group.

Irritable bowel syndrome affects an estimated 4-11% of all people, and a majority of patients prefer dietary interventions to medication.

The low FODMAP diet leads to symptom improvement in more than half of patients, but is restrictive and hard to follow.

Previous investigations from Michigan Medicine researchers into more accessible alternative diets led to a proposed “FODMAP simple,” which attempted to only restrict the food groups in the FODMAP acronym that are most likely to cause symptoms.

“Restrictive diets, such as low FODMAP, can be difficult for patients to adopt,” said Prashant Singh, MBBS, Michigan Medicine gastroenterologist and lead author on the paper.

“In addition to the issue of being costly and time-consuming, there are concerns about nutrient deficiencies and disordered eating when trying a low FODMAP diet. The Mediterranean diet interested us as an alternative that is not an elimination diet and overcomes several of these limitations related to a low FODMAP diet.”

The Mediterranean diet is already popular among physicians for its benefits to cardiovascular, cognitive, and general health. Previous research on the effect of the Mediterranean diet on IBS, however, had yielded conflicting results.

In this pilot study, two groups of patients were provided with either a Mediterranean diet or the restriction phase of a low FODMAP diet for four weeks.

The primary endpoint was an FDA-standard 30% reduction in abdominal pain intensity after four weeks.

All the patients included in the study were diagnosed with either IBS-D (diarrhea) or IBS-M (mixed symptoms of constipation or diarrhea).

This study was the first randomized controlled trial to compare the Mediterranean diet to another potential diet. (Previous studies had compared the Mediterranean diet to the individuals’ typical diets or were not randomized controlled trials.)

While the Mediterranean diet did provide symptom relief, the low FODMAP group experienced a greater improvement measured by both abdominal pain intensity and IBS symptom severity score.

Researchers found the results of this pilot study — which 20 patients completed — sufficiently encouraging to warrant future, larger controlled trials to investigate the potential of the Mediterranean diet as an effective intervention for patients with IBS.

“This study adds to a growing body of evidence which suggests that a Mediterranean diet might be a useful addition to the menu of evidence-based dietary interventions for patients with IBS,” said William Chey, M.D., chief of Gastroenterology at the University of Michigan, president-elect of the American College of Gastroenterology, and senior author on the paper.

The researchers believe studies comparing long-term efficacy of the Mediterranean diet with long-term outcomes following the reintroduction and personalization phases of low FODMAP are needed.

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Singing to babies improves their mood

Singing to your infant can significantly boost the baby’s mood, according to a recent Yale study published May 28 in Child Development.

Around the world and across cultures, singing to babies seems to come instinctively to caregivers. Now, new findings support that singing is an easy, safe, and free way to help improve the mental well-being of infants. Because improved mood in infancy is associated with a greater quality of life for both parents and babies, this in turn has benefits for the health of the entire family, the researchers say. The study also helps explain why musical behaviors may have evolved in parents.

“Singing is something that anyone can do, and most families are already doing,” said Eun Cho, postdoctoral researcher at the Yale Child Study Center, and co-first author of the study. “We show that this simple practice can lead to real health benefits for babies.”

“We don’t always need to be focusing on expensive, complicated interventions when there are others that are just as effective and easy to adopt,” added Lidya Yurdum, a PhD student in psychology at the University of Amsterdam, affiliated with the Child Study Center, and co-first author.

Increased singing improves infants’ moods

The new study included 110 parents and their babies, most of whom were under the age of four months. The researchers randomly assigned the parents into two groups, encouraging one group to sing to their infants more frequently by teaching the parents new songs, providing karaoke-style instructional videos and infant-friendly songbooks, and sending weekly newsletters offering ideas for incorporating music into daily routines.

For four weeks, these parents received surveys on their smartphones at random times throughout the day. Parents answered questions related to infant mood, fussiness, time spent soothing, caregiver mood, and frequency of musical behavior. For instance, parents were asked to rate how positive or negative their baby’s mood was within the last two to three hours before receiving the survey. The 56 parents in the control group also received an identical intervention in the four weeks following the initial experiment.

The researchers found that parents were successfully able to increase the amount of time they spent singing to their babies. “When you ask parents to sing more and provide them with very basic tools to help them in that journey, it’s something that comes very naturally to them,” said Yurdum.

Not only did the parents sing more frequently, but they also chose to use music especially in one context in particular: calming their infants when they were fussy. “We didn’t say to parents, ‘We think you should sing to your baby when she’s fussy,’ but that’s what they did,” said Samuel Mehr, an adjunct associate professor at the Child Study Center, and director of The Music Lab. Mehr is also the study’s principal investigator. “Parents intuitively gravitate toward music as a tool for managing infants’ emotions, because they quickly learn how effective singing is at calming a fussy baby.”

Most surprisingly, the responses to the survey showed that increased singing led to a measurable improvement in infants’ moods overall, compared to those in the control group — in other words, parents who sang more rated their babies’ moods as significantly higher. Importantly, improved mood was found in general, not just as an immediate response to music.

While singing did not significantly impact caregivers’ moods in this study, Mehr believes that there could be follow-on effects on health in young families. “Every parent knows that the mood of an infant affects everyone around that infant,” said Mehr. “If improvements to infant mood persist over time, they may well generalize to other health outcomes.”

Follow-up study to further explore singing’s benefits

The team believes that the benefits of singing may be even stronger than the current study shows. “Even before our intervention, these participating families were particularly musical,” Yurdum explained. “Despite that, and despite only four weeks of the intervention, we saw benefits. That suggests that the strength of singing to your babies would likely be even stronger in a family that does not already rely on music as a way of soothing their infants.”

The Child Study Center researchers are currently enrolling parents and babies under four months old in a follow-up study, “Together We Grow,” which will investigate the impact of infant-directed singing over an eight-month period.

Although the researchers did not see an improvement in caregiver mood within four weeks, they are intrigued to see if singing can help alleviate stress or conditions such as postpartum depression in the long term. They are also interested in exploring whether singing might have benefits beyond mood in infants, such as improved sleep.

Previous work from The Music Lab has shown that infant-directed music is universal in humans, and that humans can even infer context of songs — such as whether it is for dancing or a lullaby — in foreign languages and from other cultures. For Mehr, the new findings make sense in light of these basic science results. “Our understanding of the evolutionary functions of music points to a role of music in communication,” said Mehr. “Parents send babies a clear signal in their lullabies: I’m close by, I hear you, I’m looking out for you — so things can’t be all that bad.”

The babies, apparently, are listening.

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Common gene variant doubles dementia risk for men

New research has found that men who carry a common genetic variant are twice as likely to develop dementia in their lifetime compared to women.

The research, published in Neurology, used data from the ASPirin in Reducing Events in the Elderly (ASPREE) trial to investigate whether people who had variants in the haemochromatosis (HFE) gene, which is critical for regulating iron levels in the body, might be at increased risk of dementia.

Co-author Professor John Olynyk, from the Curtin Medical School, said one in three people carry one copy of the variant, known as H63D, while one in 36 carry two copies.

“Having just one copy of this gene variant does not impact someone’s health or increase their risk of dementia. However, having two copies of the variant more than doubled the risk of dementia in men, but not women,” Professor Olynyk said.

“While the genetic variant itself cannot be changed, the brain pathways which it affects — leading to the damage that causes dementia — could potentially be treated if we understood more about it.”

Professor Olynyk said further research was needed to investigate why this genetic variant increased the risk of dementia for males but not females.

“The HFE gene is routinely tested for in most Western countries including Australia when assessing people for haemochromatosis — a disorder that causes the body to absorb too much iron. Our findings suggest that perhaps this testing could be offered to men more broadly,” Professor Olynyk said.

“While the HFE gene is critical for controlling iron levels in the body, we found no direct link between iron levels in the blood and increased dementia risk in affected men.

“This points to other mechanisms at play, possibly involving the increased risk of brain injury from inflammation and cell damage in the body.”

Co-author Professor Paul Lacaze, from Monash University, said the findings could help improve outcomes for people at risk of developing dementia.

“More than 400,000 Australians are currently living with dementia, with around a third of those being men. Understanding why men with the double H63D variant are at higher risk could pave the way for more personalised approaches to prevention and treatment,” Professor Lacaze said.

“This study is a great example of how diverse Australian research groups and universities can collaborate effectively to learn more about these progressive diseases and ultimately improve health outcomes for people around the world.”

The ASPREE trial was a double-blind, randomised, placebo-controlled trial of daily low-aspirin in 19,114 healthy older people in Australia and the USA. Primarily undertaken to evaluate the risks versus benefits of daily low-dose aspirin in this cohort, it created a treasure trove of healthy ageing data that has underpinned a wealth of research studies.

The research was a collaboration between Curtin University, Monash University, The University of Melbourne, The Royal Children’s Hospital, Murdoch Children’s Research Institute and Fiona Stanley Hospital.

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Innovative immunotherapy shows promise against aggressive T cell cancers

A new type of immunotherapy that targets aggressive blood cancers shows promising results alongside manageable side effects, according to the results of an international phase 1/2 clinical trial led by researchers at Washington University School of Medicine in St. Louis.

The clinical trial evaluated the safety and efficacy of an innovative CAR-T cell immunotherapy that is specifically designed to attack cancerous T cells. Participants in the trial had been diagnosed with rare cancers — T cell acute lymphoblastic leukemia or T cell lymphoblastic lymphoma — and had run out of treatment options after standard therapy proved ineffective for them. With the new immunotherapy, most of the patients in the study who received the full dose of cells achieved full remission of their cancer.

The trial’s results were published May 30 in the journal Blood.

“For patients with these rare and aggressive cancers, who have no other options, this has the potential to become a transformative advance in the field,” said senior author John F. DiPersio, MD, PhD, the Virginia E. & Sam J. Golman Professor of Medicine at WashU Medicine, who first developed the therapy in his lab at WashU Medicine. “The trial demonstrated a high likelihood of response to the therapy and even remission. This CAR-T cell treatment shows promise in becoming a ‘bridge-to-transplant’ therapy for patients who would otherwise not be eligible for stem cell transplantation, which is the only potentially curative treatment for these blood cancers.”

Larger studies with more patients and longer follow-up are necessary before the researchers can determine whether this new therapy could be curative on its own.

The current trial included 28 adult and adolescent patients with T cell acute lymphoblastic leukemia and T cell lymphoblastic lymphoma that either returned after several lines of therapy or that never responded to treatment. About 1,000 people are diagnosed with these cancers annually in the U.S. If the cancer does not respond to treatment or returns after initial treatment, patients survive only six months, on average, and less than 7% are still living at the five-year mark.

The therapy, called WU-CART-007, was developed by Wugen, a WashU biotech startup company founded by DiPersio and other WashU Medicine investigators, including Matthew Cooper, PhD, who co-founded the company when he was on the WashU Medicine faculty and now serves as Wugen’s chief scientific officer. The researchers worked with WashU’s Office of Technology Management (OTM) to launch the company in 2018. The clinical trial was conducted in Australia, Europe and multiple sites across the U.S. For the St. Louis site, the trial was conducted at Siteman Cancer Center, based at Barnes-Jewish Hospital and WashU Medicine.

The trial design included a dose-escalation phase, which determined the recommended dose of therapeutic cells that patients would receive for the second phase of the trial. Dose escalation helps determine the largest dose of CAR-T cells that patients can receive and still have manageable side effects. Thirteen patients received the full dose of 900 million CAR-T cells after undergoing a procedure to clear the patients’ own immune cells. This procedure — called lymphodepletion — reduces immune cells, making room for the new therapeutic T cells to establish themselves and expand in number. Two of these patients died from their cancer or treatment complications, such as infection, during the study period.

Of 11 patients who could be evaluated after treatment, the overall response rate was 91%, meaning 10 patients either showed no signs of cancer after treatment or their cancer cell burden was reduced significantly. Eight out of 11 patients (72.7%) achieved complete remission. At the study’s data cut off, six who underwent a transplant remain in remission, with no evidence of disease, six to 12 months later.

“These response and remission rates — ranging from 70%-90% of patients — are much higher than we would expect from standard-of-care for this cancer type, which typically leads to remission in only 20%-40% of patients,” said first and corresponding author Armin Ghobadi, MD, a professor of medicine and clinical director of the Center for Gene and Cellular Immunotherapy at WashU Medicine. “These responses are remarkable because the patients in this trial had run out of options. They had very aggressive cancers return after several lines of therapy, including several who relapsed after an earlier stem cell transplant.”

Most patients (88.5%) experienced cytokine release syndrome as a side effect of the immunotherapy, and these cases were predominantly mild or moderate. Cytokine release syndrome is a common side effect of CAR-T cell therapy that occurs when large numbers of immune cells release chemicals that cause a full-body inflammatory response. About 19% of the patients experienced more-severe cytokine release syndrome. A small number of patients experienced rarer side effects, such as neurotoxicity syndrome and low-grade graft-versus-host disease. Adverse events were managed with additional therapies.

Off-the-shelf cell therapy

The immunotherapy evaluated in the trial is considered a “universal” CAR-T cell therapy because — harnessing CRISPR gene editing technology — it can be produced from cells donated by any healthy individual and used to treat any patient with a T cell cancer. In contrast, approved CAR-T cell therapies are adapted from the patient’s immune cells. The cells must be collected from the patient and shipped to a manufacturing facility to be made and then shipped back, a process that typically takes three to six weeks. In contrast, universal CAR-T cell therapies can be made ahead of time, stored frozen and be readily available “off-the-shelf,” greatly reducing the wait time before therapy can begin.

Using CRISPR gene editing tools, the production process deletes the T cell receptor from the donor cells, greatly reducing the risk of graft-versus-host disease, in which donor T cells attack healthy tissue. Removing another key antigen also prevents the CAR-T cells from attacking one another. The types of rare cancers in this study presented a unique challenge: the therapeutic cells and the cancer cells are both T cells, so steps must be taken to prevent the therapeutic T cells from mistaking one another for the cancer and causing CAR-T cell fratricide. All other approved CAR-T cell therapies target B cell cancers, which do not have this T cell self-targeting complication. After using CRISPR gene editing to modify the CAR-T cells to prevent these harmful side effects, the cells are further engineered to target a protein called CD7 on the surface of cancerous T cells to then destroy the cancer.

“A larger international clinical trial of this therapy is already underway,” DiPersio said. “We must complete this larger trial first, but we are hopeful this universal CAR-T cell therapy can become an approved treatment for patients with deadly T cell cancers.”

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Small currents, big impact: Satellite breakthrough reveals hidden ocean forces

What if some of the smallest ocean currents turned out to be some of the most powerful forces shaping our planet’s climate?

This question is at the center of new research co-led by Texas A&M University Department of Oceanography Associate Professor Jinbo Wang, whose work is featured on the cover of the April 17 issue of Nature. It’s a big moment for Wang and his colleagues and the global science community — marking a milestone in a billion-dollar, international water mission two decades in the making, and reflecting Texas A&M University’s long-term strategy to grow its leadership in satellite oceanography and climate research.

Wang joined Texas A&M after working at NASA’s Jet Propulsion Laboratory (JPL) in California for over nine years, where he helped lay the groundwork leading to this research alongside colleagues at JPL and France’s space agency, CNES (Centre National d’Études Spatiales) and Caltech. The recent Nature paper builds on foundational work developed by these teams during the last two decades.

What’s An Eddy — And Why Should We Care?

An eddy is like a mini whirlpool in the ocean. Picture swirling water behind a rock in a river — eddies in the ocean work in a comparable way, only much bigger and more difficult to observe. Some stretch for hundreds of kilometers and help move heat, nutrients and energy across the globe. They are vital for climate, weather and marine life.

While scientists have long studied currents of large eddies, the smaller ones — called submesoscale eddies — are notoriously difficult to detect. These currents, which range from several kilometers to 100 kilometers wide, have been the “missing pieces” of the ocean’s puzzle — until now.

New Eyes On The Ocean

Using data from the new Surface Water and Ocean Topography (SWOT) satellite, Wang and his collaborators at JPL, CNES and Caltech finally got a clear view of these hard-to-see currents.

“For the first time, we can directly observe small-scale ocean processes across the globe,” Wang said. “And it turns out they are a lot stronger than we thought.”

This breakthrough comes from the SWOT satellite, which uses a Ka-band radar interferometer to measure subtle changes in sea surface height with millimeter precision. The instrument has revealed swirling patterns and internal ocean waves — features that, until now, had never been captured at this scale from space.

“These smaller currents carry surprisingly large amounts of energy,” Wang explained. “They play a huge role in moving heat between the upper and deeper parts of the ocean and shaping how the ocean sustains its ecosystem and interacts with the atmosphere. That means they can influence marine food webs and weather patterns, like how hurricanes form and where they go, or how events like El Niño and La Niña develop. These are not just ocean features — they connect directly to the climate systems that impact all of us.”

A Happy Surprise — And A Global Breakthrough

This level of success wasn’t guaranteed. While SWOT met its science requirements, many scientists — including Wang — were not sure it would be sensitive enough to measure these subtle sea surface changes. But the engineering team behind the satellite beat expectations.

“I was pessimistic about the expected outcome before the satellite launch,” Wang said. “But the satellite performed four times better than expected. That surprise is what made this breakthrough possible.”

With better-than-expected data, the team showed that submesoscale motions — especially the spiral-shaped eddies and long internal solitary waves — are far more powerful and frequent than previously believed. These small but mighty movements stir up the ocean, helping mix warm and cold water, transport energy over long distance, which affects ocean circulation, eventually weather and climate. The study highlights the potential of these new data in helping scientists to improve their numerical models for climate predictions.

Global Teamwork, Decades In The Making

This research was made possible by the SWOT mission, a $1 billion joint effort between NASA and CNES with contributions from the U.K. and Canadian space agencies. The mission development has involved a large international team and more than 20 years of planning, testing and innovation.

“We’re building on work that started two decades ago,” said Dr. Shari Yvon-Lewis, head of the Texas A&M Oceanography Department. “Many people who helped design this satellite and the science have since retired. It’s a tribute to long-term vision, teamwork and dedication.”

Hiring Wang was a key part of Texas A&M’s investment in expanding its expertise in satellite oceanography — an area critical for understanding ocean physics and its role in the climate system. His experience at JPL and leadership in global collaborations like SWOT have positioned the university at the forefront of space-based ocean research.

Wang is also leading a NASA Ocean AI working group focused on how artificial intelligence and machine learning can help analyze existing and future satellite data and help future mission design. He is keen to contribute to the next big satellite mission.

For now, having his work featured on the cover of Nature is a moment to celebrate — and a reminder of how much the ocean can teach us.

“This is just the beginning,” Wang said. “We finally have the tools to see what’s been hiding in plain sight.”

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Why are disposable vapes being banned and how harmful is vaping?

It will be illegal to sell or supply disposable vapes from 1 June 2025.

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Disposable vapes ban unlikely to reduce appeal, says campaigner

They warn some reusable vapes have “identical” packaging to single-use ones and are sold at the same price.

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Long shot science leads to revised age for land-animal ancestor

In 1984, an amateur paleontologist in Scotland found a remarkable specimen: a nearly complete fossil of what looked to be a lizard or salamander. Rather small in size at 20 centimeters, it would turn out to be a crucial piece in the puzzle of animal evolution.

This creature, called Westlothiana lizziae, is one of the earliest examples of a four-legged animal that had evolved from living underwater to dwelling on earth. It, and other stem tetrapods like it, are common ancestors of the amphibians, birds, reptiles and mammals that exist today, including humans.

Despite its significance, researchers had never determined an accurate age of the fossil. But thanks to new research out of The University of Texas at Austin, scientists now know that the Westlothiana lizziae, along with similar salamander-like creatures from the same spot in Scotland, are potentially 14 million years older than previously thought.

The new age — dating back to 346 million years ago — adds to the significance of the find because it places the specimens in a mysterious hole in the fossil record called Romer’s Gap.

The research, published recently in the journal PLOS One, was led by Hector Garza, who just graduated with his doctoral degree from the Department of Earth and Planetary Sciences at the UT Jackson School of Geosciences. Garza took a risk when he embarked on his mission to date the ancient fossils using a geochemical technique called radiometric dating.

That’s because while geoscientists can use zircon crystals to determine how long ago a rock was formed, not all rock types are amenable to this type of analysis. And the site in Scotland where the fossils were discovered was near ancient volcanoes whose lava flows had long hardened into basalt rock, where zircons do not typically form. Fellow scientists warned Garza that chemically dating the rocks might be fruitless.

“I think that was one of the reasons why no one tried to go into them before,” Garza said. “Because of all the time and effort that it takes to obtain the zircons and then taking the risk of not finding any.”

But he got lucky. As mud cascaded down from the volcanoes, the flowing lava and debris eroded sediment that contained zircons, which got swept into a lake where limestone was forming, entombing these early tetrapod creatures.

Garza X-rayed 11 of the rock samples at the Jackson School and was able to extract zircons from the rock surrounding six of the fossils. He then conducted uranium-lead laser dating on the zircons at the University of Houston to determine their oldest possible age.

Before Garza’s gamble, scientists had figured the fossils were as old as similar fossils from around the world — about 331 million years old.

The more accurate, older maximum age of 346 million years is significant because it places the specimens in Romer’s Gap. This is a time period from 360 to 345 million years ago where, for reasons scientists are not exactly sure of, very few fossils have been discovered. It is during this crucial point in history that water-dwelling fish took an evolutionary leap, growing lungs and four legs to become land animals. This is one of the most pivotal milestones in the history of animal evolution.

“I can’t overstate the importance of the iconic East Kirkland tetrapods,” said Julia Clarke, professor at the Jackson School and co-author of this paper. “Better constraining the age of these fossils is key to understanding the timing of the emergence of vertebrates on to land. Timing in turn is key to assessing why this transition occurs when it does and what factors in the environment may be linked to this event.”

The site in Scotland where the fossils were found is the East Kirkton Quarry, a veritable treasure trove of early tetrapod records. Seven stem tetrapod fossils, including the Westlothiana lizziae, have been found there. Hundreds of millions of years ago when these early four-legged creatures roamed, this site was a tropical forest with nearby active volcanoes, a toxic lake, and a diverse plant and animal community.

The National Museum of Scotland provided Garza with bits of rock that surrounded the fossils to use for the sampling. Other study co-authors are Associate Professor Elizabeth Catlos and Michael Brookfield, both of the Department of Earth and Planetary Sciences at the Jackson School, and Thomas Lapen, professor and chair of the Department of Earth and Atmospheric Sciences at the University of Houston.

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