Friday, August 22, 2025

‘Striking sail' may have helped dinosaurs find mates, new fossil suggests

Scientists have uncovered a dinosaur with a striking back sail, perhaps used for mating displays

University of Portsmouth

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Istiorachis artist impression
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Credit: Credit: James Brown, University of Portsmouth

A new dinosaur with a dramatic sail along its back and tail has been identified from fossils found on the Isle of Wight in England - and it may have evolved its eye-catching look to impress potential mates.

The new iguanodontian dinosaur was identified by Jeremy Lockwood, a retired GP, as part of his PhD studies at the University of Portsmouth and the Natural History Museum, London. He made the discovery by carefully re-examining dinosaur bones held in the collections at the Dinosaur Isle museum, Isle of Wight.

Until now, the fossil material, which is around 125 million years old, had been assumed to belong to one of the two known iguanodontian dinosaur species from the Isle of Wight. But Lockwood noticed something unusual.

"While the skeleton wasn’t as complete as some of the others that have been found, no one had really taken a close look at these bones before", Lockwood said. "It was thought to be just another specimen of one of the existing species, but this one had particularly long neural spines, which was very unusual."

On closer inspection, Lockwood realised the animal would have probably possessed a pronounced sail-like structure along its back, helping to set it apart from other dinosaurs found on the island. His findings are described in a new paper published today in the scientific journal Papers in Palaeontology.

The animal's most striking feature is a series of extremely elongated spines along its back and tail, which probably supported a large, sail-like structure.

Lockwood explained: "Evolution sometimes seems to favour the extravagant over the practical. While the exact purpose of such features has long been debated – with theories ranging from body heat regulation to fat storage – researchers believe that the most likely explanation in this case is visual signalling, possibly as part of a sexual display and this usually is because of sexual selection”.

"In modern reptiles, sail structures often show up more prominently in males, suggesting that these attributes evolved to impress mates or intimidate rivals. We think Istiorachis may have been doing much the same."

To work out what the sail might have been for, researchers carried out a close examination of the fossilised bones. They then created a large database of similar dinosaur back bones from direct observations, photos, scientific illustrations and reconstructions, and used it to trace the evolutionary history of the heights of back bones on a new family tree of iguanodontian dinosaurs. This allowed them to spot broader trends in how these sails evolved.

Dr Jeremy Lockwood with the spinal column of Istiorachis macarthurae with some of the pelvic elements (Pubis and head of the ischium)

"These methods let us move beyond simply describing the fossil and actually test hypotheses about its function", said Lockwood. "We showed that Istiorachis’s spines weren’t just tall - they were more exaggerated than is usual in Iguanodon-like dinosaurs, which is exactly the kind of trait you'd expect to evolve through sexual selection."

The team studying the fossils included the Natural History Museum’s Prof. Susannah Maidment. Susannah commented: “Jeremy’s careful study of fossils that have been in museum collections for several years has brought to life the iguandontian dinosaurs of the Isle of Wight. His work highlights the importance of collections like those at Dinosaur Isle, where fossil specimens are preserved in perpetuity and can be studied and revised in the light of new data and new ideas about evolution. Over the past five years, Jeremy has single-handedly quadrupled the known diversity of the smaller iguanodontians on the Isle of Wight, and Istiorachis demonstrates we still have much to learn about Early Cretaceous ecosystems in the UK.

The Isle of Wight has become a hotspot for dinosaur discoveries in recent years, producing a flurry of new species. Finds like Brighstoneus, Comptonatus, and the terrifying spinosaurids Riparovenator and Ceratosuchops are helping scientists build a picture of the island as a bustling, biodiversity-rich landscape during the Early Cretaceous.

Importantly, Istiorachis appears to highlight a broader evolutionary trend. Research shows that elongation of neural spines in iguanodontians began in the Late Jurassic, before becoming a relatively common feature during the Early Cretaceous. However, true hyper-elongation, where spines stretch to more than four times the height of the vertebral body, remains rare.

Similar displays are seen in living reptiles today, including several species of lizard, where elaborate crests and sails typically signal health and strength to potential mates.

Lockwood said: "Istiorachis is a deep-time example of the same evolutionary pressures we see shaping display structures in modern animals.”

Jeremy has named the new dinosaur Istiorachis macarthurae after a famous Isle of Wight resident.

The name Istiorachis means ‘sail spine’, while macaruthurae honours Dame Ellen MacArthur, the English sailor who in 2005 set a world record for the fastest solo non-stop voyage around the world on her first attempt and who comes from the Isle of Wight.

The discovery highlights the Isle of Wight as a highly diverse ecosystem of Cretaceous life. The Wessex Formation alone represents one of the richest non-marine vertebrate fossil deposits from this period anywhere in the world, capturing a critical moment as iguanodontians blossomed from relatively obscure Jurassic herbivores into the dominant duck-billed dinosaurs of the later Cretaceous.

For palaeontologists, Istiorachis is another reminder that in evolution, sometimes it pays to show off.

Journal

Papers in Palaeontology

DOI

10.1002/spp2.70034

Method of Research

Observational study

Subject of Research

Animals

Article Title

The origins of neural spine elongation in iguanodontian dinosaurs and the osteology of a new sail‐back styracosternan (Dinosauria, Ornithischia) from the Lower Cretaceous Wealden Group of England

Dr. Jeremy Lockwood with the spinal column of Istiorachis macarthurae.

Dr. Jeremy Lockwood with spinal column of Istiorachis macarthurae.

Dr. Jeremy Lockwood with the cervical vertebra (neck) from Istiorachis macarthurae.

Credit University of Portsmouth

Istiorachis artist impression

Credit
james Brown at University of Portsmouth

Why are employees quiet quitting? Stevens researchers team up for a multidisciplinary study to find out

Perceived lack of control seems to play a role, but overall quiet quitting may not be bad for business

Stevens Institute of Technology

Hoboken, N.J., August 22, 2025 — Ever felt like doing a bare minimum at work? Not investing any extra effort, not going any extra mile? You aren’t alone. That’s a known workplace phenomenon. It’s called quiet quitting.

The term quiet quitting is used to describe the action of employees who reduce their work efforts to only the absolute minimum required for their job. Although they are not formally resigning, they are "quitting" any work and commitment beyond what's explicitly listed in their job description.

Commonly attributed to issues such as work dissatisfaction, burnout or lack of purpose, quiet quitting isn’t a new phenomenon. However, in the post-pandemic years, it has seen a definitive resurgence, prompting two Stevens researchers to team up for a study to pinpoint its underlying causes.

“We were seeing a lot of #quietquit hashtags and a lot of publicity about it,” says Assistant Professor Justine Herve whose research focuses on labor economics. “We were really puzzled by that resurgence and trying to understand what happened during the pandemic that caused this phenomenon to come back.” Herve’s colleague, Assistant Professor Hyewon Oh, who studies consumer wellbeing aimed to help people lead a happier life, was also intrigued by the phenomenon. “As a consumer psychologist, I've always been interested in what shapes people's sense of well-being and meaning in their daily lives. We started talking about quiet quitting and wondered — was it simply about disengagement at work, or was there something deeper happening?" Oh says. “This phenomenon was kind of overlapping our research interests.” So they decided to join forces.

Study authors note that quiet quitting isn’t necessarily negative. “Quiet quitting means that employees are still doing what’s expected of them, they are still performing their duties,” says Herve. “They are just not going the extra mile, not taking on extra tasks, not devoting more time to their work beyond the required hours.” That’s different from disengagement, she adds. “Refusing to perform tasks beyond what is required contractually does not necessarily imply disengagement during the agreed-upon work hours.”

What caused the resurgence of Quiet Quitting in the post-pandemic era? The collaborators hypothesized that this behavior was linked to individuals’ reduced perception of control over their circumstances in periods of uncertainty such as the pandemic. To test this, they recruited about 1400 participants through CloudResearch, an online platform that offers survey data collecting tools. The survey participants were asked a series of questions about their perception of control over their lives. Their answers led Herve and Oh to confirm their study’s hypothesis that the perceived lack of control over one’s situation could be a precursor for quiet quitting. The collaborators published their findings in the study titled Quiet Quitting in Times of Uncertainty: Definition and Relationship with Perceived Control, which appeared in the journal Human Resource Management on June 1, 2025.

Uncertainty, such as periods of political turmoil, economic instability, health or climate crises —can diminish individuals’ perception of control over their environment. That could explain why the phenomenon of quiet quitting has re-emerged in the post-pandemic era — it coincided

with a significant decline in employees’ perceived control over their circumstances. “The pandemic represented an aggregate shock to one’s perception of control,” says Herve. “There was a lot of uncertainty.”

The authors also find evidence that the association between low perceived control and high quiet quitting can be explained through two channels: on one side, a high sense of replaceability; and on the other side reduced affective commitment to the employer.

The authors point out that the relationship between perceived control and quiet quitting is complex. While lower perceived control is strongly associated with quiet quitting, the precise mechanisms and causal pathways remain an important area for future research. Understanding how feelings of replaceability, diminished affective commitment, or other psychological processes translate a loss of control into quiet quitting will require further investigation.

The collaborators also think that quiet quitting behaviors can be reduced. When people feel that they have a voice, some autonomy, and that their contributions matter, they’re less likely to scale back to the bare minimum, Oh explains. “That doesn’t just mean giving employees more tasks or perks — it’s about creating conditions where they feel their work has impact, their input is valued, and they’re not easily replaceable,” she clarifies. “Managers can take small steps, like involving employees in decision-making, clarifying how their work connects to the bigger picture, or giving them ownership over meaningful projects.” Those signals of agency and trust can go a long way in preventing quiet quitting, authors say.

Herve and Oh are excited about being able to conduct this interdisciplinary research at Stevens, which encourages cross-disciplinary projects and collaborations. “Justine studies economics, and my work is in consumer psychology and marketing, which are pretty different disciplines,” says Oh. “But because of the multidisciplinary nature of our school, we were able to join forces on such an interesting project.”

About Stevens Institute of Technology
Stevens is a premier, private research university situated in Hoboken, New Jersey. Since our founding in 1870, technological innovation has been the hallmark of Stevens’ education and research. Within the university’s three schools and one college, more than 8,000 undergraduate and graduate students collaborate closely with faculty in an interdisciplinary, student-centric, entrepreneurial environment. Academic and research programs spanning business, computing, engineering, the arts and other disciplines actively advance the frontiers of science and leverage technology to confront our most pressing global challenges. The university continues to be consistently ranked among the nation’s leaders in career services, post-graduation salaries of alumni and return on tuition investment.