NZ study supports evolutionary theory of `punctuated equilibrium’

Paleontologist Niles Eldredge sees paper as `tipping point' for acceptance of long-contentious theory

University of Auckland

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Dr Jordan Douglas

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Over the past 500 million years, nearly all evolutionary changes in octopuses and squids occurred in rapid bursts during the emergence of new species, according to research from the University of Auckland.

The findings support the theory of `punctuated equilibrium’, first proposed in the 1970s by paleontologists Stephen Jay Gould and Niles Eldredge. This controversial theory suggests that evolution is mainly not a slow, continuous process but instead happens in short, intense periods of change, followed by long stretches of stability.

The study was led by evolutionary biologist Dr Jordan Douglas from the University of Auckland’s Department of Physics. Douglas refined a probabilistic model for use with BEAST 2, a software tool for constructing evolutionary trees to test how species evolve over time.

Douglas and senior scientist Peter Wills applied the model to cephalopods (including octopuses, squids, cuttlefish, and vampire squids), as well as to the evolution of Indo-European languages, and ancient enzymes required for genetic coding. Their analysis of cephalopod traits—such as shell shapes, tentacle numbers, and fin structures—suggested that gradual evolution played only a “trivial role.”

The Indo-European languages and aminoacyl-tRNA synthetases—enzymes dating back to the dawn of life—also evolved in sudden leaps, said the scientists and co-authors Dr Remco Bouckaert, Associate Professor Simon Harris, and Professor Charlie Carter, an origin-of-life scientist from the University of North Carolina-Chapel Hill.

For the Indo-European languages, the research supported the so-called “hybrid theory,” which posits that they originated south of the Caucasus Mountains before spreading northward.

Eldredge, 81, is a curator emeritus at the American Museum of Natural History in New York. In an email to the authors of the paper, he said the new research may serve as a “tipping point” for acceptance of the theory, which has remained controversial for decades.

Over the past 50 years, the concept has been applied to everything from bacteria to dinosaurs, cancer, and even human culture, but doubts have remained about its general applicability, he said.

The new paper, using advanced mathematical techniques, confirms that rapid evolutionary change almost always coincides with the branching of new species. The paper “removes all doubt,” he said.

“Saltative branching” is the term that the University of Auckland scientists prefer to punctuated equilibrium, highlighting that the rapid evolutionary bursts take place when a new species emerges, branching off from the family tree.

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Journal

Proceedings of the Royal Society B Biological Sciences

DOI

10.1098/rspb.2025.0182 

Method of Research

Computational simulation/modeling

Subject of Research

Not applicable

Article Title

Evolution is coupled with branching across many granularities of life

 

Vigilance and targeted public health measures are essential in the face of the diphtheria epidemic that has affected vulnerable populations in Western Europe since 2022

Institut Pasteur

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Corynebacterium

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Credit: Institut Pasteur

A study published in the New England Journal of Medicine (NEJM) reveals that the largest diphtheria epidemic in Western Europe for 70 years, which broke out in 2022 among migrants and in 2023 spread to other vulnerable populations in several European countries, is the result of contaminations occurring during migratory travel or in destination European countries, and not in the countries of origin. However, the geographical area and conditions of these initial contaminations are still unknown. A genetic link has also been established between the strain that circulated during the 2022 epidemic and an epidemic that occurred in Germany in 2025, suggesting that the bacterium has been circulating silently in Western Europe. While demonstrating the effectiveness of vaccination programs for the general population, this research, carried out by an international team including researchers from the Institut Pasteur and epidemiologists from Santé publique France, underlines the importance of maintaining a high level of vigilance and public health support dedicated to diphtheria (vaccination, screening, clinical examination) among vulnerable populations in Western Europe.

In 2022, several European countries observed an unusual spike in cases of infection with the bacterium responsible for diphtheria (Corynebacterium diphtheriae), mainly among migrants who had recently arrived in Europe. Three hundred sixty-two cases were recorded in Europe that year by the European Centre for Disease Prevention and Control (ECDC). By the end of 2022, rapid intervention measures such as contact tracing and screening of secondary cases had mitigated the epidemic. In 2023, 123 cases were reported in Austria, France, Germany, Switzerland, the Netherlands and the UK (March 2025 - Emerging Infectious Diseases). Despite this decline, rare infections have been observed in these countries among migrant populations and other vulnerable populations, particularly the homeless, since 2022 and up to the present day. A total of 536 cases, including at least three deaths, have been reported in Europe since the start of the 2022 epidemic.

A clearer epidemiological picture, but the origin and scope are still unknown

The researchers analyzed 363 isolates from 362 patients in ten European countries. The data reveal that 98% of patients were male, with a median age of 18, 96% of whom had recently migrated to Europe. The majority of infections (77%) were cutaneous, with 15% of more severe respiratory forms.

The study shows that the epidemic, which has mainly affected migrant populations from Afghanistan and Syria, is not the result of initial contamination in these countries of origin, but rather contamination during migratory journeys or in reception centers in European countries. Genomic analysis of the bacterial strains circulating during the epidemic showed a very high degree of genetic proximity between the strains observed in people from different countries, implying the existence of a recent point of contact, outside the country of origin, which led to contamination. The most likely hypothesis is that this point of contact is one or more places frequented by migrants on their journey from their country of origin or in the destination countries. The exact scale of the epidemic remains difficult to determine due to the limitations inherent in screening these vulnerable populations.

Significant results for public health

"This study highlights the crucial importance of cross-border epidemiological surveillance and international collaboration in epidemic response," says Prof. Sylvain Brisse of the Institut Pasteur, one of the study coordinators. "The rapid sharing of sequencing data between countries has made it possible to define the common characteristics of diphtheria strains and adapt the health response."

In view of the major unknowns that persist with regard to this epidemic, public health experts are calling for vigilance and the strengthening of public health measures aimed at vulnerable populations in Western Europe: raising awareness of disease symptoms among doctors and, more broadly, people in contact with the vulnerable populations concerned, checking (and updating if necessary) vaccination status, appropriate antibiotic therapies, etc. Overall, the results highlight the need to step up surveillance of infectious diseases in vulnerable populations, improve access to healthcare and vaccination for migrant populations, and maintain heightened vigilance in the face of emerging antibiotic resistance.

Isabelle Parent du Châtelet, unit manager at Santé publique France states that "the study shows how important it is to ensure that diphtheria immunization levels are up to date, particularly for vulnerable population groups, such as migrants, and that diphtheria poses a risk especially among homeless people, injecting drug users, unvaccinated individuals and elderly people with pre-existing illnesses, as well as people with professional ties to these groups. It also means that clinicians need to be aware of and pay attention to the common symptoms of diphtheria, especially when their patients have a professional or other link with these vulnerable populations."

Collaborative research on an international scale

This study was conducted with financial support from the Institut Pasteur and Santé publique France as part of the missions of the National Reference Center (CNR) for diphtheria. The center was recently appointed as one of the members of the European Reference Laboratory for Diphtheria and Pertussis. The study is part of a concerted approach to diphtheria monitoring and control in Europe, led by the European Centre for Disease Prevention and Control (ECDC) and an ad hoc consortium of research and public health institutions in the countries concerned.

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Journal

New England Journal of Medicine

Subject of Research

People

Article Title

Corynebacterium diphtheriae outbreak among migrant populations in Europe

Article Publication Date

4-Jun-2025

 

Engineers make a big splash, turning water treatment sludge into sustainable concrete

University of South Australia

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By combining sludge – a byproduct of the drinking water purification process – and blast-furnace slag, University of South Australia (UniSA) engineers have demonstrated that a new, corrosive-resistant material is more than 50% stronger than cement and resistant to acid-induced degradation.

Concrete is widely used for making sewage pipes due to its availability, affordability and structural strength, but it is highly susceptible to acid and microbial corrosion in sewers, requiring ongoing repairs and maintenance that cost Australian taxpayers close to $70 billion each year.

The scale of sewage networks is immense; for instance, South Australia alone maintains over 9300 km of sewage piping [1,2], and globally, the combined length of these networks is estimated to circle the equator multiple times.

A new study published in the Journal of Building Engineering evaluates the effectiveness of the alkali-activated materials (AAMs) and demonstrates why they could revolutionise sewage infrastructure worldwide.

Samples containing 20% to 40% of alum-based water treatment sludge (AWTS) retained over 50% higher compressive strength compared to 100% ground granulated blast furnace slag (GGBS), which is used in the production of cement.

The new material also limited the penetration of sulphur-oxidizing bacteria and slowed acid-reduced degradation.

UniSA civil engineering PhD candidate Weiwei Duan, whose research is based on this project, says there is another major benefit: finding a cost-effective and environmental use for water treatment residue.

“Sludge is usually disposed of in landfill sites, which not only reduces available land for other uses, but also harms the environment, creating CO₂ emissions from transporting the waste,” Weiwei says.

Principal supervisor and lead researcher on the project, Professor Yan Zhuge, says the findings suggest that partially replacing the blast furnace slag with 20-40% of water treatment sludge makes them “promising candidates” for use in sewers.

“This has the potential to extend the service life of sewage pipes, reduce maintenance costs, and promote the reuse of water treatment byproducts, thus contributing to the circular economy.

“The construction industry is one of the world’s biggest greenhouse gas emitters, so if we can cut down on the need for cement, we will be helping to lower carbon emissions,” Prof Zhuge says.

In May, Weiwei Duan took out the 2025 Australian Water Association’s Student Water Prize for his research – the first UniSA student to receive this national honour in 60 years.

“Evaluating microbiologically influenced corrosion in alkali-activated materials incorporating alum sludge” is authored by UniSA researcher Professor Yan Zhuge, Weiwei Duan, Dr Yue Liu, Professor Christopher Chow and Alexandra Keegan from the SA Water Corporation. DOI: 10.1016/j.jobe.2025.112682

 

 

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Journal

Journal of Building Engineering

DOI

10.1016/j.jobe.2025.112682 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Evaluating microbiologically influenced corrosion in alkali-activated materials incorporating alum sludge

Article Publication Date

4-Jun-2025

 

Changing winds could amplify North Atlantic climate anomaly

University of Alaska Fairbanks

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Maps show projected sea surface temperature trends over 2015-2099 due to moderate-high greenhouse gas emissions. The upper map includes a model where winds can't change the ocean circulation, and the lower one shows the same model with wind-driven changes.

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Credit: Image by Kay McMonigal

As the planet’s oceans are gradually warmed by the effects of climate change, a huge area in the North Atlantic stands out as an unusual zone of relative cooling.

A region that stretches roughly from Greenland to Ireland, counterintuitively dubbed the North Atlantic warming hole, is a conspicuous patch of blue on global climate change maps. Researchers say its temperature contrast could intensify in the decades ahead as shifting climate-driven winds amplify the cooling process in the North Atlantic.

A new study, published this month in the Journal of Climate, projects that wind-driven changes in ocean circulation would begin adding to the cooling effect in the region by about 2040.

“Even though there’s global warming, it’s an area that’s cooling, and it’s expected to continue to cool,” said Kay McMonigal, an assistant professor at the University of Alaska Fairbanks College of Fisheries and Ocean Sciences and lead author of the study.

Scientists are still working to fully understand why the relative cooling in the North Atlantic warming hole is happening, but global circulation patterns are considered a key ingredient. That led researchers to use computer modeling to create two scenarios: one in which changing winds affect ocean circulation, and one in which they don’t.

Those models, which incorporate a moderate-high scenario for future greenhouse gas emissions, indicate that the North Atlantic warming hole won’t immediately be affected by wind-driven ocean circulation changes. That changes by about 2040, with weaker winds contributing to added cooling in the region for several decades. Lighter winds would reduce stirring in the ocean between Newfoundland and Greenland, diminishing the amount of warm subsurface water being mixed upward. Large-scale ocean circulation would then spread that cooling signal to the wider region.

Temperature shifts in the North Atlantic warming hole are an important ingredient in future climate change, with the potential to significantly affect precipitation levels and temperatures throughout the broader region. Because of that outsized role in climate impacts, a clearer understanding of the dynamics that could sustain or intensify the warming hole are important for building accurate models.

“There are a lot of implications for weather, especially over Europe,” McMonigal said. “If we want to be able to predict things well, the winds need to be accounted for.”

Other contributors to the study include Melissa Gervais, an associate professor at Pennsylvania State University, and Sarah Larson, an associate professor at North Carolina State University.

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Journal

Journal of Climate

DOI

10.1175/JCLI-D-24-0227.1 

 

From CO₂ to methane: Politecnico di Milano study featured on the cover of ACS Catalysis

Politecnico di Milano

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ACS Catalysis cover

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Credit: ACS Catalysis cover

Milan, 5 June 2025 - Every day, tonnes of CO₂ are released into the atmosphere, but what if we could transform it using clean energy? This is the question explored in a recent Politecnico di Milano study, which was featured on the cover of the scientific journal ACS Catalysis. The research focuses on a process that transforms carbon dioxide and hydrogen into methane using carefully engineered nickel nanoparticles. Entitled “Deciphering Size and Shape Effects on the Structure Sensitivity of the CO₂ Methanation Reaction on Nickel”, the study by Gabriele Spanò, Matteo Ferri, Raffaele Cheula, Matteo Monai, Bert M. Weckhuysen and Matteo Maestri investigates how the size and shape of nickel nanoparticles influence the rate at which carbon dioxide is converted into methane.

Researchers at the Laboratory of Catalysis and Catalytic Processes (LCCP) at Politecnico di Milano’s Department of Energy are tackling a key climate challenge: reusing CO₂ to produce sustainable fuels. The LCCP is an internationally recognised leader in heterogeneous catalysis, driving forward practical solutions for cleaner energy.

Combining atomistic simulations with experimental data, the team demonstrated that the size and shape of nickel nanoparticles play a decisive role in accelerating the methanation reaction. This insight resolves a longstanding scientific debate and opens new avenues for optimising other industrial processes such as ammonia synthesis and the Fischer–Tropsch process.

The study’s lead author and PhD candidate at the Politecnico di Milano’s Department of Energy Gabriele Spanò said: "Understanding the role of nanoparticle shape and size allows us to design more efficient catalysts. It’s a vital step in treating CO₂ as a resource rather than waste to be mitigated.”

Politecnico di Milano’s Department of Energy full professor and LCCP coordinator Matteo Maestri said: “This work shows that combining experimental evidence with advanced modelling can tackle complex, real-world challenges. The methodologies applied are the result of years of development in atomistic analysis for catalytic systems.”

The study offers valuable guidelines for developing catalytic materials geared towards CO₂ conversion, contributing meaningfully to the energy transition.

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Journal

ACS Catalysis

DOI

10.1021/acscatal.4c08084 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Deciphering Size and Shape Effects on the Structure Sensitivity of the CO2 Methanation Reaction on Nickel

ICYMI

CBD and related phytocannabinoids successfully clear topical fungal infections in moth larvae

PLOS

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Cryptococcus neoformans treated with CBD

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Credit: Dinh et al., 2025, PLOS Neglected Tropical Diseases, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

CBD and related phytocannabinoids show activity against fungi causing deadly cryptococcosis in moth larvae, as well as activity against fungi causing athletes foot, ringworm, and other diseases, successfully clearing topical infections.

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Access the freely-available article here: https://plos.io/4kV4DZa

Article Title: Uncovering the antifungal potential of Cannabidiol and Cannabidivarin

Author Countries: Australia, United Kingdom

Funding: This study was primarily funded by Macquarie University Research Acceleration Scheme (MQRAS298911389) grant to AKC, HD, MC and MJS. This work was supported by the Australian Research Council Industrial Transformation Training Centre for Facilitated Advancement of Australia’s Bioactives (Grant IC210100040) to AKC, MC, PAH, and ITP. EJMC was funded by the International Cotutelle Macquarie Excellence Scholarship (Cotutelle iMQRES 20224791). AKC was funded by ARC Future Fellowship FT220100152. Funders played no role in study design, data collection, analysis and interpretation of data, or the writing of this manuscript.

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Journal

PLOS Neglected Tropical Diseases

DOI

10.1371/journal.pntd.0013081 

Article Publication Date

5-Jun-2025