This brilliant, distinctive toadstool is hallucinogenic. Eating it can distort perception and cause objects to appear to expand and contract, making this mushroom at home in Wonderland. Fly amanitas inspired the magic mushrooms in Super Mario Brothers and are littered throughout art and literature. Other members of the Amanita genus, like the death-cap mushroom, are fatal.

Yet these fanciful and sometimes dangerous mushrooms are also friendly — at least to plants. Most Amanitas can only survive by closely partnering with plants, providing their roots with minerals and nutrients in exchange for sugars. This symbiosis evolved more than 50 million years ago and helps forest ecosystems thrive.

Anne Pringle, a professor of botany and bacteriology at the University of Wisconsin-Madison, researches what genetic changes drove some Amanitas away from their ancestral, decomposing lifestyle toward this intimate relationship with plants. In new work, Pringle and her collaborators show that gene loss — not the evolution of new genes — helped drive this major change in the mushrooms’ lifestyle.

The team also suspects that they’ve identified a species of Amanita that is on its way to evolving a new symbiosis with plants. In all, the results provide further evidence that symbiosis may be a lot easier to develop than scientists once thought.

Or, as Pringle puts it: “Making friends is easy.”

The new study was published Sept. 18 in the journal Molecular Biology and Evolution. Jaqueline Hess of the University of Vienna led the study, with collaborators in Norway, the Netherlands, France and Saudi Arabia.

To get at what separated symbiotic from free-living Amanitas, the researchers sequenced the genomes of three symbiotic Amanita species — including the fly amanita — and three close relatives that aren’t symbiotic. The genomic sequences allowed them to reconstruct the evolutionary paths that led to the fungi’s different adaptations.

“We went into this thinking we’d find commonalities between the three symbiotic Amanitas,” Pringle says.

But despite their similar lifestyles, symbiotic Amanitas looked vastly different from one another on the genomic level. Some symbiotic species had almost double the number of genes as their similarly symbiotic relatives. The symbiotic mushrooms seemed to take different genomic paths after they first diverged, developing unique ways to tailor their partnership with plants.

Earlier research on other families of mushrooms had suggested that one defining characteristic of symbiotic lifestyles was the loss of enzymes capable of degrading the cellulose-laden walls of plant cells. These genes are crucial for decomposers eating through leaf litter. But for fungi that associate with plants and must avoid harming their partners, cellulose-digesting enzymes are only a liability.

So when Pringle, Hess and their team looked at this group of digestive enzymes, they were surprised to find that the free-living species Amanita inopinata was missing these genes. Although symbiotic Amanita mushrooms had indeed lost this suite of digestive enzymes, Amanita inopinata‘s lack of them meant the researchers couldn’t link this loss to symbiosis itself.

Pringle says the unexpected absence of cell wall-digesting genes in Amanita inopinata‘s genome may actually be a clue pointing to evolution at work. If symbiosis only develops once fungi let go of these digestive enzymes, the researchers reason, then Amanita inopinata may be primed to evolve a closer partnership with plants.

Not quite symbiotic, perhaps not fully independent, Amanita inopinata seems to be “stuck between two worlds,” says Hess, who began the work while a postdoctoral researcher in the Pringle lab and is now a senior scientist at the University of Vienna.

The evolution of Amanita inopinata — “the unexpected one,” in Latin — and the other Amanitas also seem to support a developing consensus that symbiosis, once thought to be exceptional, may actually be easy to evolve. The researchers didn’t find that Amanita needed to develop a new, complex suite of genes in order to start partnering with plants. Instead, just letting go of a few once-vital genes may be sufficient to forge new relationships in nature.

“The story of making friends is one of loss,” says Pringle.

In a new study appearing in this week’s issue of the journal Science, researchers identified a cluster of genes related to the production of domoic acid in microscopic plants, or phytoplankton, called Pseudo-nitzschia.

The researchers, whose work is funded by the National Science Foundation (NSF), found that the genes contain the biological directions for how the toxin is made; these genes are “switched on” when Pseudo-nitzschia is producing domoic acid.

“By identifying the genes that encode domoic acid production, we are now able to ask questions about what ocean conditions turn these genes on or off,” said Patrick Brunson, lead author of the study. Brunson is affiliated with the Scripps Institution of Oceanography (SIO) and the J. Craig Venter Institute. “The knowledge will allow us to track the development of bloom toxicity at the genetic level.”

By showing how genes for domoic acid production are turned on, the authors suggest a way to connect the ocean conditions that drive algae blooms with the development of toxin production.

“Understanding how algae blooms become toxic, and what conditions cause that, are critically important,” said Hedy Edmonds, a program director in NSF’s Division of Ocean Sciences. “This study offers a possible tool for monitoring algae blooms and predicting the production of toxin before it occurs.”

Harmful algae blooms often come in the form of “red tides,” so called because of the reddish tint they lend ocean waters. The blooms occur when phytoplankton grow rapidly, sometimes producing toxins that can sicken marine mammals and other species.

Harmful algae blooms also pose a threat to human health when the toxins accumulate in seafood. A high-dose exposure to domoic acid can lead to amnesic shellfish poisoning, a potentially fatal condition marked by seizures and short-term memory loss.

Several states have been severely impacted by harmful algae blooms. The largest harmful algae bloom ever recorded happened in the summer of 2015 off the West Coast of North America from Alaska to California, and resulted in the closure of fisheries to protect consumers from potential shellfish poisoning.

Harmful algae blooms are difficult to forecast, scientists have found. The bloom-causing organisms usually have very complex genomes. Knowledge of the genes involved in domoic acid production will allow for better monitoring of algae blooms, scientists say, and aid in identifying the conditions that trigger toxin production.

“Because the genomes of the algae are so complex, the biosynthetic pathways for marine microalgae toxins have remained elusive for some time,” said senior author Bradley Moore, a chemist and geneticist at SIO and the University of California, San Diego’s Skaggs School of Pharmacy and Pharmaceutical Sciences.

“Now that we have a genome for Pseudo-nitzschia and a genetic pathway for domoic acid production, we’re beginning to understand why these microalgae make a toxin and how that capability is activated,” Moore said. “This new knowledge will better educate us on how to predict and prepare for future toxic events.”

The work advanced earlier research by David Hutchins of the University of Southern California, also a co-author of the study.

When phosphate in the ocean is limited and the amount of carbon dioxide increases, Pseudo-nitzschia can make large amounts of domoic acid and become harmful.

Carbon dioxide in the sea is increasing above natural levels. Along with rising ocean temperatures, these conditions lead to more prevalent, more toxic, and longer-lasting blooms and domoic acid production.

Researchers who work on monitoring and forecasting harmful algae blooms say the findings offer an increased understanding of the phenomenon, and will help predict domoic acid events in response to climate change.

The National Institutes of Health, the Gordon and Betty Moore Foundation and the U.S. Department of Energy also funded the research.

But in many cases, this one-way relationship between cause and effect fails to accurately describe reality. In a recent paper in Nature Communications, scientists led by Albert C. Yang, MD, PhD, of Beth Israel Deaconess Medical Center, introduce a new approach to causality that moves away from this temporally linear model of cause and effect.

“The reality in the real-world is that cause and effect are often reciprocal, as in the feedback loops seen in physiologic/endocrine pathways, neuronal regulation, ecosystems, and even the economy,” said Albert C. Yang, MD, PhD, a scientist in the Division of Interdisciplinary Medicine and Biotechnology. “Our new causal method allows for mutual or two-way causation, in which the effect of a cause can feed back to the cause itself simultaneously.”

Yang and colleagues’ new approach defines causality independently from time. Their covariation principle of cause and effect defines cause as that which when present, the effect follows, and that which when removed, the effect is removed. The team demonstrates the new approach by applying it to predator and prey systems. Moreover, Yang and colleagues showed that their model can work well in systems where other causality methods cannot work.

“I would expect the method to represent a breakthrough of causal assessment of observational data,” said Yang. “It can be applied to a wide range of causal questions in the scientific field.”

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In the journal Angewandte Chemie, researchers from the University of Illinois at Urbana-Champaign report on an electrocatalytic material made from mixing metal compounds with substance called perchloric acid.

Electrolyzers use electricity to break water molecules into oxygen and hydrogen. The most efficient of these devices use corrosive acids and electrode materials made of the metal compounds iridium oxide or ruthenium oxide. Iridium oxide is the more stable of the two, but iridium is one of the least abundant elements on Earth, so researchers are in search of an alternative material.

“Much of the previous work was performed with electrolyzers made from just two elements — one metal and oxygen,” said Hong Yang, a co-author and professor of chemical and biomolecular engineering at Illinois. “In a recent study, we found if a compound has two metal elements — yttrium and ruthenium — and oxygen, the rate of water-splitting reaction increased.”

Yao Qin, a co-author and former member of Yang’s group, first experimented with the procedure for making this new material by using different acids and heating temperatures to increase the rate of the water-splitting reaction.

The researchers found that when they used perchloric acid as a catalyst and let the mixture react under heat, the physical nature of the yttrium ruthenate product changed.

“The material became more porous and also had a new crystalline structure, different from all the solid catalysts we made before,” said Jaemin Kim, the lead author and a postdoctoral researcher. The new porous material the team developed — a pyrochlore oxide of yttrium ruthenate — can split water molecules at a higher rate than the current industry standard.

“Because of the increased activity it promotes, a porous structure is highly desirable when it comes electrocatalysts,” Yang said. “These pores can be produced synthetically with nanometer-sized templates and substances for making ceramics; however, those can’t hold up under the high-temperature conditions needed for making high-quality solid catalysts.”

Yang and his team looked at the structure of their new material with an electron microscope and found that it is four times more porous than the original yttrium ruthenate they developed in a previous study, and three times that of the iridium and ruthenium oxides used commercially.

“It was surprising to find that the acid we chose as a catalyst for this reaction turned out to improve the structure of the material used for the electrodes,” Yang said. “This realization was fortuitous and quite valuable for us.”

The next steps for the group are to fabricate a laboratory-scale device for further testing and to continue to improve the porous electrode stability in acidic environments, Yang said.

“Stability of the electrodes in acid will always be a problem, but we feel that we have come up with something new and different when compared with other work in this area,” Yang said. “This type of research will be quite impactful regarding hydrogen generation for sustainable energy in the future.”

Graduate student Pei-Chieh Shih, Zaid Al-Bardanand and Argonne National Laboratory researcher Cheng-Jun Sun also contributed to this research.

Researchers found that the steelhead trout age of migration, as well as their size and numbers, is controlled by a combination of temperature, co-occurring salmon, and other factors.

In years following large returns of pink salmon, steelhead migrated to sea at a younger age, and in some time periods, there were more young steelhead that were produced from the river system.

“We think that energy-rich eggs from spawning pink salmon provide an important food source for young steelhead,” says SFU biology PhD student Colin Bailey, who is leading the project.

SFU biology professor John Reynolds, a study co-author, also chairs the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), the federally-appointed independent committee that assesses the status of species of plants and animals across Canada.

He notes: “Many populations of steelhead are struggling, so the insights gained into their population dynamics can be helpful for conservation.”

Bailey adds: “It’s complicated — these fish seem to be controlled by many different factors at different times. We looked back through time and asked the data: do weather, spawning pink salmon, and other factors affect the steelhead life cycle?”

Next steps include examining how the survival of steelhead in the ocean is influenced by their size and age at entry to sea. This will allow researchers to determine If there are lasting effects of steelhead rearing conditions on their chance of returning to spawn.

Bailey says the research results are made possible because of a remarkable long-term field program on the Keogh River on northern Vancouver Island.

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