Parasitic fungus may have emerged 18 million years before the ants with which it lives today

Analysis of 309 strains indicates that the genus Escovopsis emerged 56.9 million years ago, but only began interacting with today’s mutualistic ants 38 million years ago, challenging the theory that they all emerged at the same time.

Fundação de Amparo à Pesquisa do Estado de São Paulo

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

An ant (genus Atta) removes fragments of a fungus garden used to feed the colony. The insects’ cleaning behavior functions as a social immune system

view more 

Credit: Quimi Vidaurre Montoya/IB-UNESP

A genus of fungi previously considered a parasite of fungi associated with ants may actually have much more complex ecological functions. According to a study published in the journal Communications Biology and supported by FAPESP, one piece of evidence is that they appeared 18 million years before the ants with which they are associated today.

The results are based on the analysis of 309 strains of the genus Escovopsis collected in eight countries in the Americas. By observing fragments of the genomes, morphological characteristics, geographic distribution, and phylogeny of the species – something like their evolutionary kinship – the researchers were able to determine the relationship with leafcutter ants over 38 million years. Escovopsis emerged 56.9 million years ago.

“Our main hypothesis is that they emerged associated with ancestral groups of fungus-growing ants and then began to coexist with the current leafcutter ants 38 million years ago. Another possibility is that they lived in a different context during those initial 18 million years, outside of their association with ants, as leaf colonizers or degrading organic matter, for example,” explains Quimi Vidaurre Montoya, the first author of the study. Vidaurre Montoya conducted the study as part of his postdoctoral research with a fellowship from FAPESP at the Institute of Biosciences of São Paulo State University (IB-UNESP) in Rio Claro, Brazil.

Leafcutter ants (subtribe Attina) cultivate fungi for food. According to a recent study by the group published in the journal Science in 2024, this mutualistic relationship is thought to have emerged 66 million years ago (read more at agencia.fapesp.br/52936). 

“Our current work is on Escovopsis, a genus of fungi that isn’t cultivated by ants, but is present in the colonies of some species of farming ants and can kill some of their cultivars. Because of this, it’s portrayed as a ‘parasite,’ when in fact only one of 24 species is known to cause infection in the fungus cultivated by ants,” Montoya explains.

The study is part of a project supported by FAPESP through the FAPESP Research Program on Biodiversity Characterization, Conservation, Restoration, and Sustainable Use (BIOTA-FAPESP), coordinated by André Rodrigues, a professor at IB-UNESP and a researcher at the Center for Research on Biodiversity Dynamics and Climate Change (CBioClima), which is one of the Research, Innovation, and Dissemination Centers (RIDCs) supported by FAPESP.

Adaptations

The authors note that Escovopsis underwent morphological and physiological adaptations over evolutionary time, apparently to increase reproductive efficiency and adapt to life inside anthills. These changes mainly occurred in the vesicles that produce conidia, which are structures that perform asexual reproduction.

“The vesicles change from a globular shape in species closer to the common ancestor to a cylindrical shape in more recent species. These changes may have been responses to barriers imposed by the ants or their symbiotic fungi,” Montoya says.

Physiological data indicate that the growth rate, number of vesicles, and production and viability of conidia gradually increased as the genus diversified. Species with cylindrical vesicles may grow faster than those with globular structures. The thinner, elongated vesicles of more recent species produce considerably more viable conidia than older groups with globular vesicles.

“Apparently, there’s a coevolution between ants, symbiotic fungi, and Escovopsis. We don’t know if they evolved to become parasites or if they're opportunists that feed on debris and can eat what remains when the system as a whole collapses. But if it were a specialized virulent host, as part of the literature assumes, it would destroy the system regardless of whether it was in equilibrium or not,” Montoya says.

Little-known fungi

This study is an offshoot of broader work on the genus Escovopsis that began during Montoya’s doctoral studies. He received a scholarship from FAPESP to conduct research under the guidance of Rodrigues. Montoya also completed an internship at Emory University in the United States.

At the time, Montoya analyzed the two largest existing collections of these fungi: the IB-UNESP collection, which was collected and maintained by Rodrigues’s group, and the Emory collection, which was maintained by Professor Nicole Marie Gerardo, Montoya’s supervisor abroad.

One of the first results of that effort was the description of two new genera previously classified as Escovopsis. Two others discovered in that work are still in the process of being described. Montoya and Rodrigues also led the description of 13 new species of Escovopsis, with ten more in the process of being described.

“These fungi are still poorly understood from physiological and ecological points of view. Therefore, it’s premature to treat them all as parasites. Our studies suggest that they have other functions and can live in relative harmony in colonies,” Montoya believes.

According to the researcher, only the Escovopsis weberi species has been proven to cause infections in fungi cultivated by ants. Experiments by his group and others show that several strains did not kill the fungi in the presence of these insects.

In vitro experiments that support the claim of parasitism disregard the fact that the affected fungi rely on ants for protection. Therefore, evaluating the effect of Escovopsis on mutualistic fungi without ants and their hygiene behaviors, which act as a social immune system, would not make sense (read more at agencia.fapesp.br/54199). 

“Some more virulent fungi are immediately removed by ants when inoculated into the colony. In experiments with Escovopsis, however, they don’t give it much importance,” the researcher says.

About São Paulo Research Foundation (FAPESP)
The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.

 

 

---

Journal

Communications Biology

DOI

10.1038/s42003-025-08654-z 

Article Title

Digging into the evolutionary history of the fungus-growing-ant symbiont, Escovopsis (Hypocreaceae

)

The genus Escovopsis emerged 56.9 million years ago, but only began interacting with today’s mutualistic ants 38 million years ago 

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

Microscopic photos, magnified 40 times, show conidiophores with cylindrical vesicles of the species Escovopsis weberi (left), which are more efficient in asexual reproduction, and globular vesicles of Escovopsis papillata (right), a species closer to the common ancestor of the genus and less efficient in this type of reproduction 

Credit

Quimi Vidaurre Montoya/IB-UNESP

Hplovecraft.comwww.hplovecraft.com/writings/texts/poetry/p289.aspx

"Fungi from Yuggoth" by H. P. Lovecraft

Oct 20, 2009 ... I. The Book The place was dark and dusty and half-lost. In tangles of old alleys near the quays, Reeking of strange things brought in from ...

GREEN  CAPITALI$M

Illinois research uncovers harvest and nutrient strategies to boost bioenergy profits

P

University of Illinois College of Agricultural, Consumer and Environmental Sciences

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

New University of Illinois Urbana-Champaign research investigates harvest and nutrient management strategies to attain maximum profitability for biomass growers.

view more 

Credit: University of Illinois Urbana-Champaign

URBANA, Ill. -- To meet ambitious U.S. Department of Energy targets for sustainable aviation fuel (SAF), production of purpose-grown energy crops must ramp up significantly. Although researchers have made substantial progress in understanding the management and conversion of these crops, key knowledge gaps hold the industry back. Now, two new studies from the University of Illinois Urbana-Champaign help fill in the blanks for Miscanthus and switchgrass management. 

“We have come a long way in our understanding of purpose-grown energy crops for SAF, but we still need to optimize agronomic management practices, like harvesting and nutrient management, to reduce production costs and incentivize growers,” said D.K. Lee, senior author of both studies and professor in the Department of Crop Sciences, part of the College of Agricultural, Consumer and Environmental Sciences at U. of I.

Previous studies have been limited in spatial scale or focused on the first years after establishment, early in the perennial life cycle. But Lee’s group is working to provide more realistic, long-term solutions to maximize biomass productivity and grow a more sustainable fuel industry. 

In the first of two recent studies, Lee’s team conducted an economic and environmental analysis of two harvest methods for switchgrass. 

“Harvesting operations account for 60-80% of the total production costs for switchgrass,” said Muhammad Umer Arshad, postdoctoral researcher in Lee’s group and first author on the Bioresource Technology paper. “We wanted to understand why the harvesting cost is so high and how each operation contributes to cost, energy use, and greenhouse gas emissions, as well as identify where reductions are possible.”

Arshad explains that switchgrass harvesting can happen via the stepwise method, in which tasks like mowing, raking, baling, and roadsiding are separated into individual operations; or the integrated method, which uses different equipment to consolidate mowing and raking into one pass. Hypothetically, an integrated approach could reduce effort, energy consumption, and costs. But, after analyzing data from 125 Virginia commercial-scale sites varying in field size and biomass yield, Arshad found a more nuanced answer.

“We found that the integrated method makes more sense for smaller fields (less than 3 hectares, or 10 acres) and low-yield (less than 3.2 tons per acre) conditions, reducing GHG emissions by 9% and energy use by 5%,” Arshad said. “The stepwise method was better for large fields with high biomass yield, reducing harvesting costs to $37.70 per ton and achieving the lowest GHG emissions.”

The costs were estimated assuming the farmers are using their own machinery, tractors, and harvesting equipment.

Lee adds that the results reveal the importance of tailoring harvesting strategies to site-specific conditions and provide the first evidence-based guidance that harvest methods can improve both economic and environmental outcomes.

In a separate study published in Biomass & Bioenergy, the team tackled age-related declines in Miscanthus biomass yield, a function of tiller (stem) mass and density. These long-lived perennial grasses follow a predictable growth trajectory, including a juvenile stage that builds over several years to reach peak biomass yield, followed by a slow decline after about 10 years. Until now, it wasn’t clear which components of yield change over time and how nutrient management might help.

Postdoctoral fellow Nictor Namoi analyzed data from a long-term Miscanthus trial with nitrogen fertilization treatments that varied in amount and timing. First, he looked at how tiller mass and density changed over time and with various nitrogen treatments. Then, he asked what other soil fertility factors may influence the decline in biomass yield in older stands. 

“We found that both tiller mass and density increase from the first year of establishment to the fourth year, and if you apply nitrogen, you get an increase in both factors,” Namoi said. “But over time, as you withdraw nitrogen by harvesting biomass, the first component to be impacted is tiller mass. So tiller mass is very sensitive to nitrogen management.”

Namoi adds that tiller density continues to increase until individual stands become saturated, with no more space for further expansion. After that point, biomass yield is determined by tiller mass. 

He notes that the decline in biomass yield over time may not be entirely tied to nitrogen. With every harvest, soil nutrients tied up in plant biomass are removed from the system, depleting elements that play a role in photosynthetic efficiency. When Namoi analyzed soil phosphorus and potassium in mature Miscanthus stands, he found significant deficits in both essential nutrients.  

“Our findings identify tiller mass as a key determinant of biomass yield in aging Miscanthus and highlight the need for nitrogen, phosphorus, and potassium management for long-term productivity,” he said.

Both studies provide practical guidance to increase profitability, a key factor for any producer looking to explore biomass crops.

The first study, “Optimizing bioenergy biofuel harvest: a comparative analysis of stepwise and integrated methods for economic and environmental sustainability,” is published in Bioresource Technology [DOI: 10.1016/j.biortech.2025.133288]. 

The second study, “Soil fertility management for sustainable Miscanthus × giganteus production: Increased tiller weight from nitrogen management explains yield gains in aged miscanthus,” is published in Biomass & Bioenergy [DOI: 10.1016/j.biombioe.2025.108394].

Research in the College of ACES is made possible in part by Hatch funding from USDA’s National Institute of Food and Agriculture. This work was also funded by the U.S. Department of Energy, Bioenergy Technologies Office (DOE-BETO) under Award Number (DE-EE0008521) and the DOE Center for Advanced Bioenergy and Bioproducts Innovation (U.S. Department of Energy, Office of Science, Biological and Environmental Research Program under Award Number DE-SC0018420).

---

Journal

Biomass and Bioenergy

DOI

10.1016/j.biombioe.2025.108394 

How did Bronze Age plague spread? A sheep might solve the mystery

University of Arkansas

\FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Univeristy of Arkansas assistant professor of anthropology Taylor Hermes.

view more 

Credit: Russell Cothren

In the Middle Ages, a plague killed a third of Europe’s population. Fleas carried the plague bacterium, Yersinia pestis, transmitting the Black Death from infected rats to millions of people. 

Another, earlier strain of Y. pestis emerged 5,000 years ago in the Bronze Age. It infected people throughout Eurasia for 2,000 years and then vanished. Unlike the Middle Age plague bacterium, this earlier Bronze Age strain could not be transmitted by fleas. How the plague circulated for so long across a vast area has long been a mystery. 

Now, an international team of researchers, including University of Arkansas archaeologist Taylor Hermes, has found the first evidence of a Bronze Age plague infection in a non-human host. The scientists discovered Y. pestis DNA in a 4,000-year-old domesticated sheep from Arkaim, a fortified settlement located in the Southern Ural Mountains of present-day Russia near the border of Kazakhstan. The discovery provides a missing link for how the Bronze Age plague spread so widely. 

The results, titled “Bronze Age Yersinia pestis genome from sheep sheds light on hosts and evolution of a prehistoric plague lineage,” were published in the journal Cell. The other authors are from Harvard University and top institutions in Germany, Russia and South Korea. 

A LUCKY DISCOVERY 

Hermes co-directs a large, ongoing study of ancient livestock DNA. By analyzing the DNA in animal bones and teeth, Hermes and his collaborators are tracing how domesticated cattle, goats and sheep spread from the Fertile Crescent throughout Eurasia and gave rise to nomadic societies and empires. 

“When we test livestock DNA in ancient samples, we get a complex genetic soup of contamination,” Hermes said. “This is a large barrier to getting a strong signal for the animal, but it also gives us an opportunity to look for pathogens that infected herds and their handlers.” 

The research is highly technical and time intensive. A host’s DNA must be filtered out from all the other DNA in the sample. Organisms that lived in the surrounding ground where the bones and teeth were buried leave their own DNA. The researchers themselves contaminate the samples with DNA from their saliva and skin cells. The recovered DNA fragments are often only 50 base pairs long. In comparison, a complete strand of human DNA is more than 3 billion base pairs. 

Animal remains are also rarely as well preserved as human remains, which are normally carefully buried. Heat from cooking the animals and the leftovers being left in trash piles and exposed to the elements degrade genetic material. 

While analyzing livestock samples excavated from Arkaim in the 1980s and 1990s, Hermes and his colleagues realized a sheep bone contained DNA from Y. pestis. 

“It was alarm bells for my team. This was the first time we had recovered the genome from Yersinia pestis in a non-human sample,” Hermes said. “We were extra excited because Arkaim is linked to the Sintashta culture, which is known for early horse riding, impressive bronze weaponry and substantial geneflow into Central Asia.” 

THE NEXT QUESTION TO ANSWER

Scientists have found numerous examples of identical strains of Bronze Age plague in humans thousands of kilometers apart. How did the disease spread so widely? 

“It had to be more than people moving. Our plague sheep gave us a breakthrough. We now see it as a dynamic between people, livestock and some still unidentified ‘natural reservoir’ for it, which could be rodents on the grasslands of the Eurasian steppe or migratory birds,” Hermes said. 

A natural reservoir is an animal that carries the bacteria but does not get sick from it. In the Middle Ages, rats were the reservoir and fleas were the vector for Y. pestis. Today, bats are often the natural reservoir for pathogens like Ebola and the Marburg virus. 

To continue this work, Hermes has received a five-year grant from Germany’s Max Planck Society for 100,000 Euros to dig for human and animal samples in the Southern Urals near Arkaim. He will be looking for more examples of Y. pestis infections. 

The Bronze Age was the moment when people in the Sintashta culture began to maintain larger herds of livestock, while also riding horses well for the first time. The Bronze Age plague was likely a result of that closer contact with animals and frequently moving into areas where they would be exposed to the reservoir. Even though it occurred thousands of years ago, Hermes believes the ancient plague has lessons for us today. 

When we encroach on natural environments with new economic needs, there can be deadly consequences. We should appreciate the delicate inner workings of the ecosystems we might disturb and aim to preserve the balance. 

“It’s important to have a greater respect for the forces of nature,” he said. 

---

Journal

Cell

DOI

10.1016/j.cell.2025.07.029 

Article Title

Bronze Age Yersinia pestis genome from sheep sheds light on hosts and evolution of a prehistoric plague lineage