Most comprehensive studies to date find 'insufficient evidence' to support herbal and dietary supplements for weight loss

EUROPEAN ASSOCIATION FOR THE STUDY OF OBESITY

Research News

 

The first global review of complementary medicines (herbal and dietary supplements) for weight loss in 16 years--combining 121 randomised placebo-controlled trials including nearly 10,000 adults--suggests that their use cannot be justified based on the current evidence.

The findings of two studies, being presented at The European Congress on Obesity (ECO) held online this year, suggest that although some herbal and dietary supplements show statistically greater weight loss than placebo, it is not enough to benefit health, and the authors call for more research into their long-term safety.

"Over-the-counter herbal and dietary supplements promoted for weight loss are increasingly popular, but unlike pharmaceutical drugs, clinical evidence for their safety and effectiveness is not required before they hit the market", says lead author Erica Bessell from the University of Sydney in Australia. "Our rigorous assessment of the best available evidence finds that there is insufficient evidence to recommend these supplements for weight loss. Even though most supplements appear safe for short term consumption, they are not going to provide weight loss that is clinically meaningful."

The authors report on herbal supplements, containing a whole plant or combinations of plants as the active ingredient, and dietary supplements containing naturally occurring isolated compounds from plants and animal products, such as fibres, fats, proteins, and antioxidants. They can be purchased as pills, powders, and liquids.

Between 1996 and 2006, 1,000 dietary supplements for weight loss included on the Australian Register of Therapeutic Goods weren't evaluated for efficacy. Supplements can be sold and marketed to the public with sponsors (who import, export or manufacture goods) required to have, but not necessarily provide, evidence backing their claims. Just 20% of new listings are audited annually to make sure they meet the requirement. In some countries, the only requirement is that supplements contain acceptable levels of non-medicinal products.

Estimates suggest that 15% of Americans trying to lose weight have tried a weight loss supplement, a USD$41 billion global industry in 2020 [1]. Despite their increasing popularity, it has been 16 years since the last review of the scientific literature on all available herbal and dietary supplements.

Herbal medicines not effective for weight loss

To provide more evidence, Australian researchers did a systematic review of all randomised trials comparing the effect of herbal supplements to placebo on weight loss, up to August 2018 [2]. Data were analysed for 54 studies involving 4,331 healthy overweight or obese adults aged 16 years or older. Weight loss of at least 2.5kg (5.5lbs) was considered clinically meaningful. They also evaluated study design, reporting, and clinical value.

Herbal supplements included in the analysis were: green tea; Garcinia cambogia and mangosteen (tropical fruits); white kidney bean; ephedra (a stimulant that increases metabolism); African mango; yerba mate (herbal tea made from the leaves and twigs of the Ilex paraguariensis plant); veld grape (commonly used in Indian traditional medicine); licorice root; and East Indian Globe Thistle (used in Ayurvedic medicine).

The analysis found that only one single agent, white kidney bean, resulted in a statistically, but not clinically, greater weight loss than placebo (-1.61kg; 3.5Ibs).

In addition, some combination preparations containing African Mango, veld grape, East Indian Globe Thistle and mangosteen showed promising results, but were investigated in three or fewer trials, often with poor research methodology or reporting, and the findings should be interpretated with caution, researchers say.

Dietary supplements don't work for weight loss

A new systematic review up to December 2019, also identified 67 randomised trials comparing the effect of dietary supplements containing naturally occurring isolated compounds to placebo for weight loss in 5,194 healthy overweight or obese adults (aged 16 years or older) [3].

Dietary supplements included in the analysis were: chitosan (a complex sugar from the hard outer layers of lobsters, crabs, and shrimp that claims to block absorption of fat or carbohydrates); glucomannan (a soluble fibre found in the roots of the elephant yam, or konjac, that promotes a feeling of fullness); fructans (a carbohydrate composed of chains of fructose) and conjugated linoleic acid (that claims to change the body composition by decreasing fat).

The analysis found that chitosan (-1.84 kg), glucomannan (-1.27 kg), and conjugated linoleic acid (-1.08 kg) resulted in statistically, but not clinically, significant weight loss compared to placebo.

Some dietary supplements, including modified cellulose (plant fibre that expands in the stomach to induce a feeling of fullness) and blood orange juice extract, showed promising results but were only investigated in one trial and need more evidence before recommending them for weight loss, researchers say.

"Herbal and dietary supplements might seem like a quick-fix solution to weight problems, but people need to be aware of how little we actually know about them", says Bessell. "Very few high-quality studies have been done on some supplements with little data on long-term effectiveness. What's more, many trials are small and poorly designed, and some don't report on the composition of the supplements being investigated. The tremendous growth in the industry and popularity of these products underscores the urgency for conducting larger more rigorous studies to have reasonable assurance of their safety and effectiveness for weight loss."

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Cricket bats should be made from bamboo not willow, Cambridge study finds

UNIVERSITY OF CAMBRIDGE

Research News

 

IMAGE: CO-AUTHOR BEN TINKLER-DAVIES EXAMINES A PROTOTYPE BAMBOO CRICKET BAT view more 

CREDIT: BEN TINKLER-DAVIES

Bamboo cricket bats are stronger, offer a better 'sweet spot' and deliver more energy to the ball than those made from traditional willow, tests conducted by the University of Cambridge show. Bamboo could, the study argues, help cricket to expand faster in poorer parts of the world and make the sport more environmentally friendly.

"The sound of leather on willow" may have delighted cricket lovers for generations but the sport should now consider making the blades of its bats with bamboo, say researchers from Cambridge's Centre for Natural Material Innovation.

Dr Darshil Shah and Ben Tinkler-Davies compared the performance of specially made prototype laminated bamboo cricket bats, the first of their kind, with that of typical willow bats. Their investigations included microscopic analysis, video capture technology, computer modelling, compression testing, measuring how knocking-in improved surface hardness, and testing for vibrations.

The study, published today in The Journal of Sports Engineering and Technology, shows that bamboo is significantly stronger - with a strain at failure more than three times greater - than willow and able to hold much higher loads, meaning that bats made with bamboo could be thinner while remaining as strong as willow. This would help batsmen as lighter blades can be swung faster to transfer more energy to the ball. The researchers also found that bamboo is 22% stiffer than willow which also increases the speed at which the ball leaves the bat.

During manufacture, the surface of cricket bats is compressed to create a hardened layer. When the team compared the effect of this 'knock-in' process on both materials, they found that after 5 hours bamboo's surface hardness had increased to twice that of pressed willow.

Perhaps most excitingly, they found that the sweet-spot on their prototype bamboo blade performed 19% better than that on a traditional willow bat. This sweet-spot was about 20 mm wide and 40 mm long, significantly larger than on a typical willow bat, and better still, was positioned closer to the toe (12.5 cm from the toe at its sweetest point).

Co-author, Dr Darshil Shah, a former member of Thailand's under-19 national cricket team, said: "This is a batsman's dream. The sweet-spot on a bamboo bat makes it much easier to hit a four off a Yorker for starters, but it's exciting for all kinds of strokes. We'd just need to adjust our technique to make the most of it, and the bat's design requires a little optimisation too."

The pair also tested for comfort and found that bamboo had a similar 'damping ratio' to willow meaning that a similar amount of force is transferred to a player's hands when they strike the ball. In other words, players using bamboo bats wouldn't feel any more vibration than if they tried out a willow bat.

CAPTION

Bamboo cricket bat prototype and section of bamboo

CREDIT

Ana Gatóo

The study points out that there is a shortage of good-quality willow, which takes up to 15 years to mature - mostly in England - to the point where the wood can be used to make cricket bats. Even then, bat makers often have to throw away a large quantity (up to 30%) of the wood they source.

By contrast, Moso and Guadua, the two most suitable types of structural bamboo, grow abundantly in China, across Southeast Asia and South America. These bamboos mature twice as fast as willow and because the cell structure in the laminated material is more regular, less raw material is wasted during manufacture. The researchers believe that high performance, low-cost production and increased sustainability could make bamboo cricket bats a viable and ethical alternative to willow.

Co-author Ben Tinkler-Davies said: "Cricket brings you really close to nature, you spend hours out in the field, but I think the sport can do a lot more for the environment by promoting sustainability. We've identified a golden opportunity to achieve that while also helping lower income countries to produce bats at lower cost."

In the nineteenth century, cricket bat makers experimented with various types of wood but from the 1890s, they settled on the sapwood of Salix Alba, a light coloured willow, for the blade as it offered high stiffness, low density and visual appeal. The use of cane in cricket has been limited to bat handles and pads.

Working with local a cricket bat manufacturer Garrard & Flack, the researchers made a full-size bamboo bat prototype. They first had to split the bamboo culms into lengths (about 2.5 metres long), plane them flat and then stack, glue and laminate them into solid planks ready to be cut into different sizes. While this sounds laborious, using laminated bamboo avoids the rolling processes needed to harden willow. The cell structure of bamboo naturally has a higher density than willow.

The materials used to make cricket bats are regulated by the Marylebone Cricket Club (MCC), the sport's governing body, and Law 5.3.2 states that "The blade shall consist solely of wood".

Shah said: "Bamboo is a grass not a wood so there would need to be discussions with the MCC but we think playing with a bamboo bat would be within the spirit of the game because it's a plant-based material and cane, a type of grass, is already used in the handle."

But what about that iconic sound of leather on willow? "We tested that too", Tinkler-Davies said. "The frequency when willow strikes the ball is very similar - whether you're playing or spectating, you wouldn't notice much of a difference."

To those left feeling "It's just not cricket", Dr Shah said: "Tradition is really important but think about how much cricket bats, pads, gloves and helmets have already evolved. The width and thickness of bats have changed dramatically over the decades. So if we can go back to having thinner blades but made from bamboo, while improving performance, outreach and sustainability, then why not?"

The researchers now hope to enter into discussions with the MCC and leading bat manufacturers.

Tinkler-Davies said: "Our first prototype bat is 40% heavier than most full-size willow cricket bats so we now need to work out the optimum design to reduce that. Because laminated bamboo is so strong, we're very confident we can make a bamboo bat light enough, even for today's fast-scoring, short forms of the game."

Reference

B. Tinkler-Davies, M. H. Ramage & D. U. Shah, 'Replacing willow with bamboo in cricket bats', Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology (2021). DOI: 10.1177/17543371211016592

CAPTION

Co-author Dr Darshil Shah with bamboo cricket bat prototype and section of bamboo

CREDIT

Darshil Shah

Smartphone breath alcohol testing devices vary widely in accuracy

Some failed to detect users were over legal driving limit more than half the time, Penn medicine research finds

UNIVERSITY OF PENNSYLVANIA SCHOOL OF MEDICINE

Research News

PHILADELPHIA-- Alcohol-impaired driving kills 29 people a day and costs $121 billion a year in the U.S. After years of progress in reducing alcohol-impaired driving fatalities, efforts began to stall in 2009, and fatalities started increasing again in 2015. With several studies demonstrating that drinkers cannot accurately estimate their own blood alcohol concentration (BAC), handheld alcohol breath testing devices, also known as breathalyzers, allow people to measure their own breath alcohol concentration (BrAC) to determine if they are below the legal limit of .08% before attempting to drive.

The latest generation of personal alcohol breath testing devices pair with smartphones. While some of these devices were found to be relatively accurate, others may mislead users into thinking that they are fit to drive, according to a new study from the Perelman School of Medicine at the University of Pennsylvania.

The findings, published today in Alcoholism: Clinical & Experimental Research, compares the accuracy of six such devices with that of two validated alcohol-consumption tests - BAC taken from venipuncture, and a police-grade handheld breath testing device.

"All alcohol-impaired driving crashes are preventable tragedies," says lead investigator M. Kit Delgado, MD, MS, an assistant professor of Emergency Medicine and Epidemiology at Penn. "It is common knowledge that you should not drive if intoxicated, but people often don't have or plan alternative travel arrangements and have difficulty judging their fitness to drive after drinking. Some may use smartphone breathalyzers to see if they are over the legal driving limit. If these devices lead people to incorrectly believe their blood alcohol content is low enough to drive safely, they endanger not only themselves, but everyone else on the road or in the car."

To assess these devices, researchers engaged 20 moderate drinkers between the ages of 21 and 39. The participants were given three doses of vodka over 70 minutes with the goal of reaching a peak BAC over the legal driving limit of around 0.10%. After each dose, participants' BrAC was measured using smartphone-paired devices and a police-grade handheld device. After the third dose, their blood was drawn and tested for BAC, the most accurate way of measuring alcohol consumption. Researchers also explored the devices' ability to detect breath alcohol concentration above common legal driving limits (0.05% and 0.08%). They used statistical analysis to explore differences between the measurements.

All seven devices underestimated BAC by more than 0.01%, though the some were consistently more accurate than others. Two devices failed to detect BrAC levels of 0.08% as measured by a police-grade device more than half the time. Since the completion of the study, one of the devices was discontinued and is no longer sold, and other models have been replaced by newer technologies. However, two of the other devices had similar accuracy as a police-grade device. These devices have been used to remotely collect accurate measurements of alcohol consumption for research . They could also be used to scale up contingency management addiction treatment programs that have been shown to help promote abstinence among patients with alcohol use disorders. These programs, which have proven to be highly effective, have traditionally provided prizes for negative in person breathalyzer measurements. Smartphone breathalyzer apps allow these programs to be administered remotely as breath alcohol readings can be verified with automatically captured pictures of the person's face providing the reading and prize redemption could be automated.

"While it's always best to plan not to drive after drinking, if the public or addiction treatment providers are going to use these devices, some are more accurate than others. Given how beneficial these breathalyzer devices could be to public health, our findings suggest that oversight or regulation would be valuable," Delgado concludes. "Currently, the Food and Drug Administration doesn't require approval for these devices - which would involve clearance based on review of data accuracy - but it should reconsider this position in light of our findings."

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Research reported in this publication was supported by the Centers for Disease Control and Prevention (R49 CE002474) and the National Institutes of Health (K23 HD090272001 and UL1 TR001878). This research was also supported in part by the VISN 4 Mental Illness Research, Education and Clinical Center of the Department of Veterans Affairs and Abramson Family Foundation Fund for Acute Care and Injury Prevention Research.

Penn Medicine is one of the world's leading academic medical centers, dedicated to the related missions of medical education, biomedical research, and excellence in patient care. Penn Medicine consists of the Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania (founded in 1765 as the nation's first medical school) and the University of Pennsylvania Health System, which together form a $8.9 billion enterprise.

The Perelman School of Medicine has been ranked among the top medical schools in the United States for more than 20 years, according to U.S. News & World Report's survey of research-oriented medical schools. The School is consistently among the nation's top recipients of funding from the National Institutes of Health, with $496 million awarded in the 2020 fiscal year.

The University of Pennsylvania Health System's patient care facilities include: The Hospital of the University of Pennsylvania and Penn Presbyterian Medical Center--which are recognized as one of the nation's top "Honor Roll" hospitals by U.S. News & World Report--Chester County Hospital; Lancaster General Health; Penn Medicine Princeton Health; and Pennsylvania Hospital, the nation's first hospital, founded in 1751. Additional facilities and enterprises include Good Shepherd Penn Partners, Penn Medicine at Home, Lancaster Behavioral Health Hospital, and Princeton House Behavioral Health, among others.

Penn Medicine is powered by a talented and dedicated workforce of more than 44,000 people. The organization also has alliances with top community health systems across both Southeastern Pennsylvania and Southern New Jersey, creating more options for patients no matter where they live.

Penn Medicine is committed to improving lives and health through a variety of community-based programs and activities. In fiscal year 2020, Penn Medicine provided more than $563 million to benefit our community.

Physicists describe new type of aurora

Discovery comes from reanalysis of two-decade-old video

UNIVERSITY OF IOWA

Research News

VIDEO: THE FAMED NORTHERN AND SOUTHERN LIGHTS HAVE BEEN STUDIED FOR MILLENNIA, BUT THEY STILL HOLD SECRETS. IN A NEW STUDY, PHYSICISTS LED BY THE UNIVERSITY OF IOWA DESCRIBE A NEW... view more 

CREDIT: RILEY TROYER, UNIVERSITY OF IOWA

For millennia, humans in the high latitudes have been enthralled by auroras--the northern and southern lights. Yet even after all that time, it appears the ethereal, dancing ribbons of light above Earth still hold some secrets.

In a new study, physicists led by the University of Iowa report a new feature to Earth's atmospheric light show. Examining video taken nearly two decades ago, the researchers describe multiple instances where a section of the diffuse aurora--the faint, background-like glow accompanying the more vivid light commonly associated with auroras--goes dark, as if scrubbed by a giant blotter. Then, after a short period of time, the blacked-out section suddenly reappears.

The researchers say the behavior, which they call "diffuse auroral erasers," has never been mentioned in the scientific literature. The findings appear in the Journal of Geophysical Research Space Physics.

Auroras occur when charged particles flowing from the sun--called the solar wind--interact with Earth's protective magnetic bubble. Some of those particles escape and fall toward our planet, and the energy released during their collisions with gases in Earth's atmosphere generate the light associated with auroras.

"The biggest thing about these erasers that we didn't know before but know now is that they exist," says Allison Jaynes, assistant professor in the Department of Physics and Astronomy at Iowa and study co-author. "It raises the question: Are these a common phenomenon that has been overlooked, or are they rare?

"Knowing they exist means there is a process that is creating them," Jaynes continues, "and it may be a process that we haven't started to look at yet because we never knew they were happening until now."

It was on March 15, 2002, that David Knudsen, a physicist at the University of Calgary, set up a video camera in Churchill, a town along Hudson Bay in Canada, to film auroras. Knudsen's group was a little disheartened; the forecast called for clear, dark skies--normally perfect conditions for viewing auroras--but no dazzling illumination was happening. Still, the team was using a camera specially designed to capture low-level light, much like night-vision goggles.

Though the scientists saw only mostly darkness as they gazed upward with their own eyes, the camera was picking up all sorts of auroral activity, including an unusual sequence where areas of the diffuse aurora disappeared, then came back.

Knudsen, looking at the video as it was being recorded, scribbled in his notebook, "pulsating 'black out' diffuse glow, which then fills in over several seconds."

"What surprised me, and what made me write it in the notebook, is when a patch brightened and turned off, the background diffuse aurora was erased. It went away," says Knudsen, a Fort Dodge, Iowa, native who has studied aurora for more than 35 years and is a co-author on the study. "There was a hole in the diffuse aurora. And then that hole would fill back in after a half-minute or so. I had never seen something like that before."

The note lay dormant, and the video unstudied, until Iowa's Jaynes handed it to graduate student Riley Troyer to investigate. Jaynes learned about Knudsen's recording at a scientific meeting in 2010 and referenced the eraser note in her doctoral thesis on diffuse aurora a few years later. Now on the faculty at Iowa, she wanted to learn more about the phenomenon.

"I knew there was something there. I knew it was different and unique," says Jaynes, assistant professor in the Department of Physics and Astronomy. "l had some ideas how it could be analyzed, but I hadn't done that yet. I handed it to Riley, and he went much further with it by figuring out his own way to analyze the data and produce some significant conclusions."

Troyer, from Fairbanks, Alaska, took up the assignment with gusto.

"I've seen hundreds of auroras growing up," says Troyer, who is in his third year of doctoral studies at Iowa. "They're part of my heritage, something I can study while keeping ties to where I'm from."

Troyer created a software program to key in on frames in the video when the faint erasers were visible. In all, he cataloged 22 eraser events in the two-hour recording.

"The most valuable thing we found is showing the time that it takes for the aurora to go from an eraser event (when the diffuse aurora is blotted out) to be filled or colored again," says Troyer, who is the paper's corresponding author, "and how long it takes to go from that erased state back to being diffuse aurora. Having a value on that will help with future modeling of magnetic fields."

Jaynes says learning about diffuse auroral erasers is akin to studying DNA to understand the entire human body.

"Particles that fall into our atmosphere from space can affect our atmospheric layers and our climate," Jaynes says. "While particles with diffuse aurora may not be the main cause, they are smaller building blocks that can help us understand the aurora system as a whole, and may broaden our understanding how auroras happen on other planets in our solar system."

CAPTION

Notes written by David Knudsen, a physicist at the University of Calgary, in 2002 make mention of a "pulsating 'black out' diffuse glow, which then fills in over several seconds." Two decades later, University of Iowa physicists describe the phenomenon, in which patches of the background glow are blotted out, then suddenly intensify and reappear.

CREDIT

David Knudsen, University of Calgary

Study co-authors are Sarah Jones, from NASA Goddard Space Flight Center and who was part of Knudsen's team in Churchill, and Trond Trondsen, with Keo Scientific Ltd., who built the camera that filmed the diffuse aurora.

NASA supported the data analysis.

 

Artificial color-changing material that mimics chameleon skin can detect seafood freshness

CELL PRESS

Research News

 

IMAGE: THIS IMAGE SHOWS THE COLOR CHANGE OF THE "CHAMELEON SKIN " HYDROGEL-BASED CHEMOSENSOR IN RESPONSE TO BIOGENIC VOLATILE AMINE VAPORS, WHICH ARE A WELL KNOWN INDICATOR OF FISH AND SHRIMP SPOILAGE.... view more 

CREDIT: LU ET AL./CELL REPORTS PHYSICAL SCIENCE

Scientists in China and Germany have designed an artificial color-changing material that mimics chameleon skin, with luminogens (molecules that make crystals glow) organized into different core and shell hydrogel layers instead of one uniform matrix. The findings, published May 6 in the journal Cell Reports Physical Science, demonstrate that a two-luminogen hydrogel chemosensor developed with this design can detect seafood freshness by changing color in response to amine vapors released by microbes as fish spoils. The material may also be used to advance the development of stretchable electronics, dynamic camouflaging robots, and anticounterfeiting technologies.

"This novel core-shell layout does not require a careful choice of luminogen pairs, nor does it require an elaborate design and regulation of the complex photophysical interactions between different luminogens," says Tao Chen, a professor at the Ningbo Institute of Materials Technology and Engineering at the Chinese Academy of Sciences and an author of the study. "These advantages are important to the future construction of robust multicolor material systems with as-yet-unachieved performance."

While scientists have long envisioned developing soft materials that can fluctuate between a wide range of fluorescent colors with ease, synthetic materials are rarely able to change hue as artfully as chameleons do.

"Most artificial color-changing soft materials have been prepared by simultaneously incorporating two or more responsive luminogens into one single elastomer or hydrogel matrix," says Chen. "On the other hand, the organization of different iridophores into two superposed core-shell structured layers constitutes an evolutionary novelty for panther chameleons that allows their skins to display complex structural colors."

To determine whether artificial color-changing materials could be imbued with the natural core-shell structure of chameleon skin, Wei Lu, a researcher at the Ningbo Institute of Materials Technology and Engineering at the Chinese Academy of Sciences, and colleagues developed a multi-luminogen layered hydrogen system from the inside out. First, the researchers synthesized a red fluorescent core hydrogel, which would serve as a template for the other layers. This core hydrogel was incubated in various aqueous Europium solutions, after which the gel was incubated in a growth solution containing sodium alginate and responsive blue/green fluorescent polymers. Spontaneous diffusion of Europium ions from the core hydrogel into the surrounding solution triggered the formation of blue and green hydrogel layers.

Because of the way that the core and shell layers of the hydrogels overlapped, they could change from red to blue or green when triggered by changes in temperature or pH. The authors also note that the emission color of the blue and green fluorescent layers could be adjusted, enabling the material to display colors from nearly the full visible spectrum.

"The proposed diffusion-induced interfacial polymerization to prepare core-shell materials proves to be general," says Chen. "It is thus highly expected that the proposed synthetic strategy could be expanded to produce other soft color-changing materials, such as smart hydrogels or elastomers with stimuli-responsive structural color or pigment color change."

To test the abilities of a chemosensor crafted from a two-luminogen hydrogel to detect seafood freshness, Lu and colleagues sealed test strips made from the material in boxes with fresh shrimp or fish for 50 hours. The test strip stored with seafood at less than -10?C barely changed from its original red fluorescent color, indicating that the food was still fresh, while the test strip stored with seafood at 30?C shifted to a vivid green hue, indicating that the food had spoiled.

Chen suggests that both the novel core-shell hydrogels and the diffusion-induced interfacial polymerization strategy used to make them could prove useful in a diverse range of scientific fields, including robotics.

"In the near future, we plan to utilize the developed chameleon skin-like core-shell hydrogels to prepare biomimetic soft camouflaging skins, which can be used to mimic the diverse color-changing functions of living organisms' skins and to help achieve desirable active camouflage, display and alarm functions in robots," says Chen.

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This work was supported by the National Natural Science Foundation of China, the Sino-German Mobility Program, the Key Research Program of Frontier Sciences, Chinese Academy of Sciences, the Youth Innovation Promotion Association of Chinese Academy of Sciences, and the Open Fund of the Guangdong Provincial Key, Laboratory of Luminescence from Molecular Aggregates, South China University of Technology.

Cell Reports Physical Science, Lu et al.: "Panther Chameleon skin-inspired core@shell supramolecular hydrogel with spatially organized multi-luminogens enables programmable color change" https://www.cell.com/cell-reports-physical-science/fulltext/S2666-3864(21)00107-7

Cell Reports Physical Science (@CellRepPhysSci), published by Cell Press, is a new broad-scope, open access journal that publishes cutting-edge research across the spectrum of the physical sciences, including chemistry, physics, materials science, energy science, engineering, and related interdisciplinary work. Visit: https://www.cell.com/cell-reports-physical-science/home. To receive Cell Press media alerts, please contact press@cell.com.

What can a dinosaur's inner ear tell us? Just listen

YALE UNIVERSITY

VIDEO: INNER EAR ENDOCAST OF THE TOOTHED "NEAR-BIRD " HESPERORNIS REGALIS SHOWING THE ARCHES OF THE VESTIBULAR SYSTEM ABOVE AND THE ELONGATED COCHLEA BELOW. view more 

CREDIT: MICHAEL HANSON AND BHART-ANJAN S. BHULLAR

New Haven, Conn. -- If paleontologists had a wish list, it would almost certainly include insights into two particular phenomena: how dinosaurs interacted with each other and how they began to fly.

The problem is, using fossils to deduce such behavior is a tricky business. But a new, Yale-led study offers a promising entry point -- the inner ear of an ancient reptile.

According to the study, the shape of the inner ear offers reliable signs as to whether an animal soared gracefully through the air, flew only fitfully, walked on the ground, or sometimes went swimming. In some cases, the inner ear even indicates whether a species did its parenting by listening to the high-pitched cries of its babies.

"Of all the structures that one can reconstruct from fossils, the inner ear is perhaps that which is most similar to a mechanical device," said Yale paleontologist Bhart-Anjan Bhullar, senior author of the new study, published in the journal Science.

"It's so entirely dedicated to a particular set of functions. If you are able to reconstruct its shape, you can reasonably draw conclusions about the actual behavior of extinct animals in a way that is almost unprecedented," said Bhullar, who is an assistant professor of earth and planetary sciences and an assistant curator at the Yale Peabody Museum of Natural History.

Working with colleagues at the American Museum of Natural History, Bhullar and first author Michael Hanson of Yale compiled a matrix of inner ear data for 128 species, including modern-day animals such as birds and crocodiles, along with dinosaurs such as Hesperornis, Velociraptor, and the pterosaur Anhanguera.

Hesperornis, an 85-million-year-old bird-like species that had both teeth and a beak, was the inspiration for the research. The Yale Peabody Museum of Natural History has the world's only three-dimensional fossil that preserves a Hesperornis inner ear.

"I was aware of literature associating cochlear dimensions with hearing capability, and semicircular canal structure with locomotion in reptiles and birds, so I became curious as to how Hesperornis would fit into the picture," said Hanson, a graduate student at Yale.

Hanson and Bhullar analyzed the Hesperornis inner ear with CT scanning technology to determine its three-dimensional shape.

Next, the researchers conducted the same analysis with a variety of other fossils -- and current species -- to determine whether the inner ear provided strong indications of behavior. In many cases, the researchers created 3D models from crushed or partially-crushed skull fossils.

After assembling the data, the researchers found clusters of species with similar inner ear traits. The clusters, they said, correspond with the species' similar ways of moving through and perceiving the world.

Several clusters were the result of the structure of the top portion of the inner ear, called the vestibular system. This, said Bhullar, is "the three-dimensional structure that tells you about the maneuverability of the animal. The form of the vestibular system is a window into understanding bodies in motion."

One vestibular cluster corresponded with "sophisticated" fliers, species with a high level of aerial maneuverability. This included birds of prey and many songbirds.

Another cluster centered around "simple" fliers like modern fowl, which fly in quick, straight bursts, and soaring seabirds and vultures. Most significantly, the inner ears of birdlike dinosaurs called troodontids, pterosaurs, Hesperornis, and the "dino-bird" Archaeopteryx fall within this cluster.

The researchers also identified a cluster of species which had a similar elongation of the lower portion of the inner ear -- the cochlear system -- that has to do with hearing range. This cluster featured a fairly large group of species, including all modern birds and crocodiles, which together form a group called archosaurs, the "ruling reptiles."

Bhullar said the data suggest that the cochlear shape's transformation in ancestral reptiles coincided with the development of high-pitched location, danger, and hatching calls in juveniles.

It implies that adults used their new inner ear feature to parent their young, the researchers said.

"All archosaurs sing to each other and have very complex vocal repertoires," Bhullar said. "We can reasonably infer that the common ancestors of crocodiles and birds also sang. But what we didn't know was when that occurred in the evolutionary line leading to them. We've discovered a transitional cochlea in the stem archosaur Euparkeria, suggesting that archosaur ancestors began to sing when they were swift little predators a bit like reptilian foxes."

CAPTION

A dinosaur parent glides down to its nest, using its specialized vestibular system to coordinate its landing and its elongated cochlea to hear its babies' chirps.

CREDIT

Michael Hanson and Bhart-Anjan S. Bhullar

Co-authors of the study are Mark Norell and Eva Hoffman of the American Museum of Natural History.

The Yale Department of Earth & Planetary Sciences, the Yale Institute for Biospheric Studies, the American Museum of Natural History, and the National Science Foundation funded the research.

CAPTION

Hesperornis, from the collections of the Yale Peabody Museum of Natural History.

CREDIT

Yale Peabody Museum of Natural History.

Slender-snouted Besanosaurus was an 8 m long marine snapper

Paleontologists working in museum collections in Italy, Switzerland, and Germany have identified five additional specimens of a 240-million-year-old ichthyosaur, named Besanosaurus leptorhynchus, which was previously known from a single fossil housed

PEERJ

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IMAGE: THE SKULL OF THE TYPE SPECIMEN OF BESANOSAURUS LEPTORHYNCHUS IS CHARACTERIZED BY EXTREME LONGIROSTRY (I.E., THIN ELONGATE SNOUT), AND EQUIPPED WITH TINY POINTED TEETH, PERFECT FOR CATCHING SMALL FISH AND... view more 

CREDIT: GABRIELE BINDELLINI AND MARCO AUDITORE, © MUSEO DI STORIA NATURALE DI MILANO.

Middle Triassic ichthyosaurs are rare, and mostly small in size. The new Besanosaurus specimens described in the peer-reviewed journal PeerJ - the Journal of Life and Environmental Sciences - by Italian, Swiss, Dutch and Polish paleontologists provide new information on the anatomy of this fish-like ancient reptile, revealing its diet and exceptionally large adult size: up to 8 meters, a real record among all marine predators of this geological epoch. In fact, Besanosaurus is the earliest large-sized marine diapsid - the group to which lizards, snakes, crocodiles, and their extinct cousins belong to - with a long and narrow snout.

Besanosaurus leptorhynchus was originally discovered near Besano (Italy) three decades ago, during systematic excavations led by the Natural History Museum of Milan. The PeerJ article re-examines its skull bones in detail and assigns five additional fossils to this species: two previously undescribed fossil specimens, and two fossils previously referred to a different species (Mikadocephalus gracilirostris), which turns out to be not valid due to lack of significant anatomical differences with Besanosaurus.

The six specimens vary mainly in size and likely represent different growth stages. According to this re-analysis, Besanosaurus is the oldest and basal-most representative of a group of ichthyosaurs known as shastasaurids.

All specimens, housed in museums in Milan, Zurich, and Tübingen were collected in the last century from the bituminous black shales of the Monte San Giorgio area (Italy/Switzerland, UNESCO World Heritage), which were deposited some 240 million years ago at the oxygen-depleted bottom of a peculiar marine basin. The locality is famous worldwide for its rich fossil fauna that, besides ichthyosaurs, includes many other marine and semiaquatic reptiles, a variety of fish, and hard-shelled invertebrates.

"The extremely long and slender rostrum suggests that Besanosaurus primarily fed on small and elusive prey, feeding lower in the food web than an apex predator: a novel ecological specialisation never reported before this epoch of the Triassic in a large diapsid reptile. This might have triggered an increase of body size and lowered competition among the diverse ichthyosaurs that co-existed in this part of the Tethys Ocean", says Gabriele Bindellini of the Earth Science Dept. of Milan University, first author of this study.

"Studying these fossils was a real challenge. All Besanosaurus specimens have been extremely compressed by deep time and rock pressure, so we used advanced medical CT scanning, photogrammetry techniques and comparisons with other ichthyosaurs to reveal their hidden anatomy and reconstruct their skulls in 3D, bone by bone", remarks Cristiano Dal Sasso of the Natural History Museum of Milan, senior author of the PeerJ article, who in 1996 originally described and named Besanosaurus.

Interestingly, the Italian researchers started re-studying the Milan Besanosaurus roughly at the same time an international team including Andrzej Wolniewicz (IP PAS, Warsaw), Feiko Miedema (SMNS, Stuttgart), and Torsten Scheyer (UZH, Zurich) started working on the Swiss specimens. "Rather than doing parallel studies, we pooled our data and efforts and pulled on the same string, to enhance our understanding of these fascinating extinct animals", adds Torsten Scheyer.

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Images:

Image 1: The first and most complete fossil of Besanosaurus leptorhynchus is a pregnant female (containing one embryo) on display at the Milan Natural History Museum, together with a fiberglass reconstruction of its in-life aspect. 16.500 hours of manual preparation were needed to expose the entire skeleton, embedded in a 330x270 cm black shale layer. Credit: Gabriele Bindellini, © Museo di Storia Naturale di Milano.

Image 2: The skull of the type specimen of Besanosaurus leptorhynchus is characterized by extreme longirostry (i.e., thin elongate snout), and equipped with tiny pointed teeth, perfect for catching small fish and extinct cousins of squids with rapid snapping moves of the head and jaws. Credits: Gabriele Bindellini and Marco Auditore, © Museo di Storia Naturale di Milano.

Image 3: A view of Lake Lugano from Monte San Giorgio, between Lombardy (Italy, left) and Canton Ticino (Switzerland, right). Ichthyosaurs are among the most abundant fossils of this UNESCO World Heritage locality, which protects a unique paleo-biodiversity dating back to the Middle Triassic (240 million of years ago). Credit: Gabriele Bindellini.

Image 4: At the Zurich Institute and Museum of Paleontology, Gabriele Bindellini measures the orbital diameter of a subadult Besanosaurus leptorhynchus. This fossil preserves some three-dimensional anatomy, which helped to re-define the "identity card" of the species. Credit: Cristiano Dal Sasso.

Image 5: At the Zurich Institute and Museum of Paleontology, Cristiano Dal Sasso opens the display case of a remarkably large ichthyosaur specimen that, if complete, would have measured 8 meters in length. Although disarticulated, the skull indicates it is another Besanosaurus... Credit: Gabriele Bindellini.

Image 6: Reconstruction of Besanosaurus. In spite of their fish-like aspect, ichthyosaurs were reptiles. They were perfectly adapted to marine life through large modifications of their land-dwelling ancestors' limbs into paddles. Dorsal fins and crescentic tails also developed in later, more advanced forms. Pencil by Fabio Fogliazza digitally modified by Gabriele Bindellini, © Museo di Storia Naturale di Milano.

Image 7. The "Sasso Caldo" site, near Besano (Varese, Italy) in 1995. This outcrop is characterized by a regular alternance of thin black bituminous shales, and thicker grey-whitish dolomitized layers. Fossils are found in both, although in the shales the specimens are highly deformed. Photo by Giorgio Teruzzi, © Museo di Storia Naturale di Milano.

Image 8. Spring 1993, Besano (Varese, Italy): a snapshot of the recovery of the most complete specimen of Besanosaurus leptorhynchus. To avoid damaging the fossil, the bones of the large ichthyosaur were detected in cross-section, along the cuts of the slabs, without splitting the layer that embedded them firmly. The chisels in the photo were used only to detach the fossil-bearing layer from the underlying one. Photo by Cristiano Dal Sasso, © Museo di Storia Naturale di Milano.

Image 9. At the Fondazione Ospedale Maggiore di Milano, on the CT screen appears the Besanosaurus skull, with the orbital cavity (bottom center) surrounded by the bones of the temporal region. Photo by Cristiano Dal Sasso.

Image 10. At the Natural History Museum of Milan, the preparators of the Laboratory of Paleontology remove the silicon layer that, poured on the recomposed skeleton of Besanosaurus leptorhynchus, allows to produce identical replicas of the original fossil. © Photo by Guido Alberto Rossi and Museo di Storia Naturale di Milano.

Image 11. In the thoracic region of the Milan Besanosaurus, where the stomach was located, food remains are preserved, including this tiny hooklet from a squid relative's arm. Cephalopods were preferred prey for several species of ichthyosaurs. Photo by Gabriele Bindellini, © Museo di Storia Naturale di Milano.

Image 12. The "Sasso Caldo" site of Besano (Varese, Italy) as it appears today. The outcrop is extremely rich in fossils in almost every rock layer. In this picture, paleontologist Cristiano Dal Sasso indicates with his right hand the bituminous layer n. 65, in which the former Besanosaurus was embedded, and with his left hand the layer n. 63, which provided two small ichthyosaurs of the genus Mixosaurus. Photo by Gabriele Bindellini.

Image 13. At the Fondazione Ospedale Maggiore di Milano, paleontologist Gabriele Bindellini (left) and a student of the Degree in Medical Techniques of Radiology, Alessandro Crasti (right), scan the skull of Besanosaurus leptorhynchus before shifting it into the CT ring. Photo by Cristiano Dal Sasso.

Image 14. At the Institute and Museum of Paleontology of the Zurich University, paleontologists Cristiano Dal Sasso (left) and Torsten Scheyer (right) chat in front of the largest Besanosaurus - recently identified as such - unearthed in the first half of the last century from Swiss mines of Monte San Giorgio. If complete, this specimen would have approached 8 meters in length. Photo by Gabriele Bindellini.

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About:

PeerJ is an Open Access publisher of seven peer-reviewed journals covering biology, environmental sciences, computer sciences, and chemistry. With an emphasis on high-quality and efficient peer review, PeerJ's mission is to give researchers the publishing tools and services they want with a unique and exciting experience. All works published by PeerJ are Open Access and published using a Creative Commons license (CC-BY 4.0). PeerJ is based in San Diego, CA and the UK and can be accessed at peerj.com

PeerJ - the Journal of Life and Environmental Sciences is the peer-reviewed journal for Biology, Medicine and Environmental Sciences. PeerJ has recently added 15 areas in environmental science subject areas, including Natural Resource Management, Climate Change Biology, and Environmental Impacts. peerj.com/environmental-sciences

Across its journals, PeerJ has an Editorial Board of over 2,000 respected academics, including 5 Nobel Laureates. PeerJ was the recipient of the 2013 ALPSP Award for Publishing Innovation. PeerJ Media Resources (including logos) can be found at: peerj.com/about/press