OREGON STATE UNIVERSITY

college of science

Terrifed insect escapes a permanent tomb – 50 million years ago

CORVALLIS, Ore. – Thousands of insects, plants and other life forms have been found trapped in ancient amber deposits, but a new discovery shows a rarity of a different type – the one that got away.

In a piece of Baltic amber about 50 million years old, research has uncovered an exoskeleton similar to that of a modern-day “walking stick” – evidence of an insect that literally was frightened out of its skin, and made its way to freedom just as it was about to become forever entombed by oozing tree sap.

The unusual piece also reveals the first mushroom that’s ever been found in Baltic amber, along with a mammalian hair that was left behind. In its entirety, the amber piece offers a little docudrama of life, fear and hasty escape in the ecology of an ancient subtropical forest.

The findings were just published in Fungal Biology by George Poinar, Jr., a researcher in in the College of Science at Oregon State University and an international expert in ancient life forms found in amber.

“From what we can see in this fossil, a tiny mushroom was bitten off, probably by a rodent, at the base of a tree,” Poinar said. “An insect, similar to a walking stick, was probably also trying to feed on the mushroom. It appears to have immediately jumped out of its skin and escaped, just as tree sap flowed over the remaining exoskeleton and a hair left behind by the fleeing rodent.”

Plants, insects and other material found in amber deposits, Poinar said, always offer details about ancient ecosystems. But on rare occasions such as this, they also show the interactions and ecology between different life forms. They are invaluable in helping scientists to reconstruct the nature of ecosystems in the distant past.

In this case, the amber came from near the Baltic Sea in what’s now Germany, Poland, Russia and Scandinavia. It was formed, beginning as a viscous tree sap, in a large subtropical coniferous forest across much of northern Europe that lasted about 10 million years.

In a climate much warmer than exists there today, the early angiosperms, or flowering plants, were starting to displace the gymnosperms, or cone-bearing evergreens that had previously been dominant. Dinosaurs had gone extinct a few million years before, and mammals were beginning to diversify.

“The tiny insect in this fossil was a phasmid, one of the kinds of insects that uses its shape to resemble sticks or leaves as a type of camouflage,” Poinar said.

“It would have shed its skin repeatedly before reaching adulthood, in a short lifespan of a couple months. In this case, the ability to quickly get out of its skin, along with being smart enough to see a problem coming, saved its life.”

The exoskeleton seen in the amber is extremely fresh and shows filaments that would have disappeared if it had been shed very long before being covered by amber, Poinar said.

This particular insect species is now extinct, as is the mushroom in the fossil, Poinar said. Although mushrooms have been found in fossils from other regions of the world, this is the first specimen to be identified in Baltic amber, and represents both a new genus and species.

The Baltic amber deposits are the largest in the world, have been famous for thousands of years and continue to be mined today. Amber from the mines were traded by Roman caravans, later taken over by Teutonic knights and are known around the world for the huge volume of semi-precious stones they produce.

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George Poinar, Jr.

poinarg@science.oregonstate.edu

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Narrow escape
Insect escapes

World’s greatest butterfly collection takes shape

CORVALLIS, Ore. – Researchers at 27 universities and museums around the United States have begun creating what will soon become the world’s greatest butterfly collection – in digital form.

When complete, the collection should comprise data from about three million butterfly and moth specimens in North America, providing invaluable data to answer ecological and scientific questions never before possible.

The initiative is supported by a $3.2 million grant from the National Science Foundation and is being coordinated by the Colorado Plateau Biodiversity Center at Northern Arizona University.

“For anyone who’s ever created an insect collection, butterflies and moths are the poster children,” said Christopher Marshall, curator of the Oregon State Arthropod Collection in the Oregon State University College of Science, which is one of the participants in this project.

“Butterflies generate such a huge base of enthusiasm that people have been collecting them for centuries,” Marshall said. “But the gigantic data set that this new collection will make possible is going to help us understand butterflies and moths in ways we never could before, looking back in time and gaining insights into the future.”

The digitized data, he said, will allow scientists to see where different butterflies and moths have lived, what changes may have taken place over time, and how they might have been affected by shifts in climate or seasonality. They can study where and when non-native species have arrived, or where native species have been pushed out or extirpated. It will show what species survived and thrived, which ones dwindled and died.  It will also help scientists visualize under-sampled places, where more surveys might turn up new, undiscovered species.

The ecological time machine offered by such data will not only be useful now, Marshall said, but will help scientists a century or two in the future better understand the ecological effects of a changing world.

Lepidoptera, the order of insects that includes butterflies and moths, is one of the most widespread, colorful and recognized in the world. They make up more than 200,000 of the 3 million specimens in the Oregon State Arthropod Collection, which is directed by David Maddison and is one of the top 10 university-owned butterfly and moth collections in the nation.

OSU plans to contribute about 140,000 butterfly and moth records to this collaboration. This data will be of particular value to the project, Marshall said, because OSU’s holdings are strong in Pacific Northwest species. The varied geographic terrain and unique geological history of Oregon also supports a diverse set of species that live in habitat ranging from coastal rain forests to valleys, mountains, prairies and high sagebrush desert.

“Ecological change is constant, and studies of lepidoptera, which are often linked to particular plants and microhabitats, offer a means to examine how things are changing,” Marshall said.

“We have in our collection a single butterfly specimen collected by a schoolboy in Eugene in the 1930s that is now gone from Oregon. Dana Ross, a volunteer in our work, recently brought in a specimen of a moth from Jackson County, Oregon, that was last seen 80 years ago and is one of only three specimens collected in the state.

“As we put the scattered data from all these specimens together, we can begin to see patterns not visible with only a handful of records. This in turn lets us address bigger, more complex questions about the changing biodiversity in the world around us.”

Some work on this project has already begun at OSU. Both volunteers and student employees will be used on the project over the next four years. People interested in volunteering can contact Marshall at marshach@science.oregonstate.edu

Having long caught the fascination of humans, about 180,000 species of lepidoptera comprise 10 percent of the total described species of living organisms. Butterflies and moths play major roles in ecosystems as pollinators; their larvae as consumers of vegetation; and themselves as an important part of the food web for other animals.

This project will include the effort of citizen scientists, and organizers say they hope for it to stimulate education, public awareness and conservation efforts about butterflies. At OSU, there are literally hundreds of digitized collections related to natural history and other important fields of science.

“Digitizing these data will have a significant impact for centuries, as big data and analytics become more omnipresent,” said Sastry G. Pantula, dean of OSU’s College of Science. “A number of species are becoming extinct and new species are being discovered. We are grateful to the National Science Foundation and our policy makers for their vision to support such collections and expand access, especially given the recent constraints on federal funding.”

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Editor’s Note: Tube and high resolution downloadable video are available to illustrate this story.

High definition researcher interview and B-roll video: https://drive.google.com/folderview?id=0B_nEpHVYyPtpLVVndk5OZzdsWDA&usp=sharing

Watch-only YouTube video: https://youtu.be/agc_8WKvksI

 

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Christopher Marshall, 541-737-4349

marshach@science.oregonstate.edu

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Endangered butterfly
Fender's blue butterfly

Twenty years of progress: nutrition emerging as a “hard science” in human health

CORVALLIS, Ore. – A much better understanding of the role of diet and supplements in maintaining optimum health well into old age has emerged over the past 20 years, according to one expert, and today is helping to address chronic diseases that kill most people in the developed world - heart disease, stroke, diabetes and cancer.

As he retires this month after leading the Linus Pauling Institute at Oregon State University since 1997, Balz Frei, director and distinguished professor of biochemistry and biophysics in the College of Science, has outlined some of the key advances of that period, and the steps still needed for nutrition researchers to work more closely and successfully with the medical community.

In the recent past, Frei said, nutritional research was rife with inconclusive studies that showed  associations but no firm cause-effect relationships of disease prevention. Long-term trials with humans to study disease prevention are difficult and often cost prohibitive, and laboratory animal tests that showed effects – such as the effect of a certain food on cancer incidence - often lacked an explanation of “why.”

In the past two decades, a period of extraordinary growth for the Linus Pauling Institute, researchers have worked to answer that question of “why” with considerable success.

“What I wanted to achieve with the institute was to put science behind nutrition,” Frei said. “We’re helping to lead the field of nutrition into more science and mechanism-based research that can have a real impact on promoting human health and preventing disease.”

In this research, an underlying cause of aging and chronic disease has now emerged – chronic inflammation. Inflammation and its accompanying surge of “free radicals” are tied to several major killers, including cardiovascular disease and certain cancers.  Scientists are honing in on the mechanisms of inflammation and the antioxidants that can prevent free radical damage.

Important discoveries have been made with vitamin E, in particular, in understanding why this nutrient is required by the body and the role it plays in protecting critical fats, especially during brain development and in the aging brain. Research on vitamin C showed that it helps arteries relax and lowers high blood pressure, a chief cause of stroke.

The institute has also helped change the world view of vitamins and other nutrients. Instead of seeing them simply as a way to correct or prevent a deficiency condition like scurvy, they are increasingly recognized as a way to help prevent chronic disease, counter toxins and contribute to healthier aging.

One molecule in particular, lipoic acid, has shown promise in its ability to “bring cells back to a youthful state,” Frei said. This compound triggers a reaction in cells that makes them more capable of fending off free radicals and other toxic insults that cause inflammation and disease.

Other findings of importance during Frei’s tenure at the institute include:

  • The discovery and mechanisms of action of several phytochemicals that may help prevent cancer, metabolic syndrome, and cardiovascular disease.
  • Compounds of particular interest range from catechins in tea to quercetin in onions, sulforaphane in broccoli and xanthohumol in hops.
  • Chlorophyll, a phytochemical that gives plants their green color, can bind to a toxic mold compound called aflatoxin that causes liver cancer, and render it inactive.
  • Omega-3 fatty acids found in fish or fish oil have been shown to have important health effects, including their role in halting progression of fatty liver disease.
  • The role of vitamin D in boosting the body’s immune system is being viewed with significant future importance, with the advent of multi-drug resistant bacteria, including one recently confirmed strain that resists medicine’s last-ditch antibiotic.

“Vitamin D plays a crucial role in many functions of the body, not just bone health, and it’s now a public health challenge to raise the levels of it in the population worldwide, so that everyone has the best shot at fighting infections,” Frei said. “LPI works beyond the ivory tower to help people make the right decisions regarding the use of diet and dietary supplements.”

An important future goal, Frei said, would be a full outreach to the medical community.

“Communication between the nutrition science and medical communities is not happening at the scale it needs to right now,” he said. “We need a bridge, and LPI, its Micronutrient Information Center and other public outreach services are well-suited to be that bridge. If we could bring about a change in how medical doctors are educated, I think that would be a major contribution to public health.”

There’s an urgency to change perceptions on diet and supplements among the medical community as well as the general public, Frei said, as rates of chronic, preventable diseases continue to increase.

“There’s so much misleading information out there, so many false promises when it comes to dietary supplements,” Frei said. “We’re trying to counter these claims with evidence-based health information about vitamins, minerals, and phytochemicals. It has been, and to some extent continues to be an uphill battle for nutrition science to establish itself as a ‘hard’ science. But there’s also a realization now of how critical the field is to human health.”

During Frei’s tenure as director, LPI has grown from one principal investigator to 12, focused on the study of healthy aging, cardiometabolic disease prevention, and cancer prevention and intervention.

More than 650 published research papers and review articles have been cited by peers over 26,000 times, and more than $55 million in funding came from the National Institutes of Health and other agencies.

The institute’s endowment has quadrupled since its inception at OSU, and during the university’s recent capital campaign LPI raised $48 million, $15 million of which went toward the construction of the Linus Pauling Science Center, a state-of-the-art research and education facility.

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Anne Glausser, 541-737-5881

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Balz Frei, 541-737-5078

balz.frei@oregonstate.edu

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balz_frei
Balz Frei

Coral reefs fall victim to overfishing, pollution aggravated by ocean warming

CORVALLIS, Ore. – Coral reefs are declining  around the world because a combination of factors – overfishing, nutrient pollution, and pathogenic disease – ultimately become deadly in the face of higher ocean temperatures, researchers have concluded.

A study published today in Nature Communications, based on one of the largest and longest field experiments done on this topic, suggests that the widespread coral deaths observed in recent decades are being caused by this combination of multiple local stressors and global warming.

These forces greatly weaken corals, and allow opportunistic pathogens to build to such levels that corals cannot survive.

The findings were made by researchers from six institutions following a three-year experiment that simulated both overfishing and nutrient pollution on a coral reef in the Florida Keys. The large body of field data collected over an extended period of time helped resolve some of the fundamental questions about the cause of coral reef declines, scientists said.

“This is grim news, but at least it will help settle the argument over why corals are dying,” said Rebecca Vega Thurber, an assistant professor in the College of Science at Oregon State University and corresponding author on the study.

“This makes it clear there’s no single force that’s causing such widespread coral deaths. Loss of fish that help remove algae, or the addition of excess nutrients like those in fertilizers, can cause algal growth on reefs. This changes the normal microbiota of corals to become more pathogenic, and all of these problems reach critical levels as ocean temperatures warm.”

The end result, scientists say, is a global decline of coral reefs that is now reaching catastrophic proportions.

“We need to know how human activities are affecting coral reef ecosystems,” says David Garrison, program director in the National Science Foundation’s Division of Ocean Sciences, which funded the research.  “Coral reefs are among the most sensitive indicators of the health of the oceans. This report is a major contribution toward understanding how reefs will fare in the future.”

Scientists say the problems caused by bacterial infections due to local stressors and warm temperatures are in addition to damage from mass coral bleaching events already under way. Only in the early 1980’s did researchers observe the first mass bleaching event in recorded history. There have now been three such events just in the past 20 years.

“About 25-35 percent of the corals on the Great Barrier Reef are dying right now,” Vega-Thurber said. “In 2014-16 large portions of tropical reef across the planet experienced bleaching, and this past April, 90 percent of the Great Barrier Reef bleached as part of a massive El Nino event. Corals everywhere seem to be dying.”

In addition to helping to sort out the effects of known stressors like overfishing and nutrient pollution, the researchers made one bizarre and totally unexpected finding.

In normal conditions, parrotfish, like many other species, are essential to the health of coral reefs, nibbling at them to remove algae and causing no permanent damage. But in one part of the experiment corals were so weakened by nitrogen and phosphorus pollution that when parrot fish would bite them, 62 percent of the corals would die. A normally healthy fish-coral interaction had been turned into a deadly one.

“Normally benign predation by the parrotfish turned into coral murder,” said Deron Burkepile, also a corresponding author on the study at the University of California – Santa Barbara. “But it’s not the parrotfishes, they’re like the reef janitors, keeping it clean. Those extra nutrients — nutrient pollution — turn parrotfishes into an actual source of mortality by facilitating pathogens in the wounds left by their bites. Excess nutrients turn a coral accomplice into a coral killer.”

The researchers said they want to make it clear that parrotfish are not the problem, they are an essential part of healthy reef ecosystems.

“The problem is when corals are so weakened they cannot withstand normal impacts,” Vega-Thurber said. “And the solution will be to help those corals recover their health, by ensuring that their local environment is free of nutrient pollution and that fish stocks are not depleted.”

Among the findings of the study:

  • Overfishing, nutrient pollution and increased temperature all lead to an increase in pathogens;
  • The sheer abundance of pathogens is more important than what particular type or species they are;
  • Coral reef mortality mirrors the abundance of pathogens;
  • Heat exacerbates these problems, with 80 percent of coral deaths coming in the summer or fall, but only when fish are removed or nutrient pollution is present;
  • While high thermal stress has received the most attention, even modest temperature increases make corals more vulnerable to bacteria;
  • Loss of fish can increase algal cover up to six times;
  • In a distressed system with many algae, coral disease levels double and coral mortality increases eight times;
  • Increased algal cover or elevated temperature can reduce levels of naturally-secreted antibiotics that help protect corals from harmful bacteria;
  • Direct algal contact driven by overfishing and nutrient pollution destabilizes the coral microbiome, in some cases leading to a 6- to 9-time increase in mortality.

The findings, researchers say, make it clear that in the face of global warming, some of the best opportunities to protect coral reefs lie in careful management of fishing and protection of water quality. This would give corals their best chance to have a healthy microbiome and resist warmer conditions without dying.

Collaborators on this research were from Florida International University, the University of California/Santa Barbara, Penn State University, Rice University, the University of Florida/Gainsville, SymbioSeas and Marine Applied Research Center, and the Laboratoire d’Excellence.

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Editor Notes: Video and audio are available to illustrate this story.

 

Interview with Rebecca Vega-Thurber:  http://bit.ly/1TSUe1N

Link to audio-only version of same interview: http://bit.ly/24ubTg0

YouTube view-only link of same video: https://youtu.be/dq8jtyuYp_U

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Rebecca Vega-Thurber, 541-737-1851

rebecca.vega-thurber@oregonstate.edu

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Coral surveys

Divers in field study


Sampling coral microbiome


Testing coral microbiome


Experimental design


Study design


Parrot fish on coral reefs
Parrot fish cleaning coral

Common antimicrobial agent rapidly disrupts gut bacteria

CORVALLIS, Ore. – A new study suggests that triclosan, an antimicrobial and antifungal agent found in many consumer products ranging from hand soaps to toys and even toothpaste, can rapidly disrupt bacterial communities found in the gut.

The research was published today in PLOS ONE by scientists from Oregon State University. It was based on findings made with zebrafish, which researchers believe are an important animal model to help determine possible human biological and health impacts of this antimicrobial compound.

Triclosan was first used as a hospital scrub in the 1970s and now is one of the most common antimicrobial agents in the world, found in shampoos, deodorants, toothpastes, mouth washes, kitchen utensils, cutting boards, toys, bedding, socks and trash bags. It continues to be used in medical settings, and can be easily absorbed through the skin.

“There has been a legacy of concern about exposure to microbial pathogens, which has led to increased use of these antimicrobial products,” said Thomas Sharpton, an assistant professor of microbiology and statistics in the OSU Colleges of Science and Agricultural Sciences, and corresponding author on the new study.

“However, there’s now a growing awareness of the importance of the bacteria in our gut microbiome for human health, and the overuse of antibiotics that can lead to the rise of ‘superbugs.’ There are consequences to constantly trying to kill the bacteria in the world around us, aspects we’re just beginning to understand.”

In the new study, researchers found that triclosan exposure caused rapid changes in both the diversity and composition of the microbiome in the laboratory animals. It’s not clear what the implication may be for animal or human health, but scientists believe that compromising of the bacteria in the intestinal tract may contribute to the development or severity of disease.

Some bacteria were more susceptible to the impact of triclosan than others, such as the family Enterobacteriaceae; and others were more resilient, such as the genus Pseudomonas.

“Clearly there may be situations where antibacterial agents are needed,” said Christopher Gaulke, lead author on the study and a postdoctoral microbiology researcher in the OSU College of Science.

“However, scientists now have evidence that intestinal bacteria may have metabolic, cardiovascular, autoimmune and neurological impacts, and concerns about overuse of these agents are valid. Cumulative impacts are also possible. We need to do significantly more evaluation of their effects, some of which might be dramatic and long lasting.”

The gut-associated microbiome performs vital functions for human health, prevents colonization with pathogens, stimulates the development of the immune system, and produces micronutrients needed by the host. Dysfunction of this microbiome has been associated with human disease, including diabetes, heart disease, arthritis and malnutrition, the scientists pointed out in their study.

Humans are routinely exposed to an array of chemicals, metals, preservatives, microbes and nutrients, some of which may be beneficial, some innocuous, and others harmful, the researchers said. Part of the strength of the present study is developing improved ways, through rapid screening of zebrafish, to more easily determine which compounds may be acceptable and which are toxic, scientists say.

Triclosan has been a concern in part because it is so widely used, and it’s also readily absorbed through the skin and gastrointestinal tracts, showing up in urine, feces and breast milk. It also has been associated with endocrine disruption in fish and rats, may act as a liver tumor promoter, and can alter inflammatory responses.

This study showed it was quickly associated with shifts in the microbial community structure and can alter the abundance of specific taxa.

Collaborators on this research included scientists from the OSU Environmental Health Sciences Center and OSU College of Agricultural Sciences.

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Thomas Sharpton, 541-737-8623

thomas.sharpton@oregonstate.edu


Sea star juveniles abundant, but recovery is anything but guaranteed

CORVALLIS, Ore. – An unprecedented number of juvenile sea stars have been observed off the Oregon coast over the past several months – just two years after one of the most severe marine ecosystem epidemics in recorded history nearly wiped the population out.

The appearance of the juveniles does not mean the threat of “sea star wasting disease” is over, researchers caution. A second round of the disease could be disastrous to the purple ochre (Pisaster ochraceus) and other sea stars, some of which are considered “keystone” species in marine habitats because of their influence on the ecosystem.

A team of Oregon State University scientists who have been monitoring the sea stars for years reported on their status this week in the journal PLOS ONE.

“When we looked at the settlement of the larval sea stars on rocks in 2014 during the epidemic, it was the same or maybe even a bit lower than previous years,” said Bruce Menge, the Wayne and Gladys Valley Professor of Marine Biology at Oregon State University and lead author on the study. “But a few months later, the number of juveniles was off the charts – higher than we’d ever seen – as much as 300 times normal.”

“It wasn’t a case of high settlement, or more sea stars being born. They just had an extraordinary survival rate into the juvenile stage. Whether they can make it into adulthood and replenish the population without succumbing to sea star wasting disease is the big question.”

Menge and his colleagues believe the reason for the high survival rate is the availability of more food. The young sea stars feed on larval and juvenile mussels and barnacles, competing with adult sea stars for the same food source. The scarcity of adults provided a temporary smorgasbord for the juveniles.

Sea star wasting disease first appeared in Oregon in the summer of 2014. In rocky intertidal habitats, disease rapidly depleted populations of the dominant sea star, Pisaster ochraceus. The sea stars first developed twisted arms, then showed deflation and lesions, and eventually lost arms and the ability to grip onto the substrate before finally disintegrating completely.

Over a period of about 15 months, the disease reduced the overall sea star population by 63 to 84 percent at different site along the Oregon coast, and reduced the Pisaster ochraceus population by 80 to 99 percent. The epidemic ranged from Alaska to Baja California.

Scientists from Cornell University attributed the epidemic to a Sea Star-associated Densovirus and researchers in Washington say warmer water may have provided the trigger for the disease in that state.

But Menge’s research group found no association between water temperature and the disease outbreak in Oregon.

“The sea temperatures were warmer when the outbreak first began,” he said, “but Oregon wasn’t affected as early as other parts of the West Coast, and the outbreak reached its peak here when the sea temperature plummeted and was actually cooler than normal.”

The Cornell researchers found evidence of densovirus in the sea stars, the water column and in sediments. It occurs naturally and can become virulent, possibly as a result of stress.

“Something triggered that virulence and it happened on a coast-wide basis,” said Menge, a distinguished professor in the Department of Integrative Biology in OSU’s College of Science. “We don’t think it was a result of warming because conditions were different in Oregon than they were, for example, in Washington and likely other parts of the West Coast. Ocean acidification is one possibility and we’re looking at that now. Ultimately, the cause seems likely to be multi-faceted.”

Menge and his research team have been studying these intertidal rocky zones at different sites for as long as 32 years and analyzing the community structure. Historical research has shown that the ochre star is a “keystone” species because of its influence in these ecosystems, suggesting that the absence of so many adults could have a significant impact.

Ochre sea stars prey on barnacles and mussels and keep their populations under control. When left unchecked, mussel populations can explode, covering up algae and small invertebrates.

“The longer-term ecological consequences of this (disease) event could include wholesale elimination of many low zone species and a complete change in the zonation patterns of rocky intertidal communities along the West Coast of North America,” the authors wrote in their study.

Among the other findings the OSU researchers reported in PLOS One:

  • Sea stars that were continuously submerged, such as those in tidepools, had a higher rate of the disease than sea stars on rocks outside of tidepools where periodically they were above water;
  • During the last two years, the number of gooseneck barnacles has exploded along the coast – likely because they are not being preyed upon as heavily by adult sea stars;
  • Adult sea stars are much more likely to be affected by sea star wasting disease than juveniles, which may be because of longer exposure or some other factor.

The OSU research has been funded by the David and Lucile Packard Foundation, the National Science Foundation, the Kingfisher Foundation, and the Wayne and Gladys Valley Foundation.

Other authors on the study, all from OSU, include Elizabeth Cerny-Chipman, Angela Johnson, Jenna Sullivan, Sarah Gravem and Francis Chan.

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Bruce Menge, 541-737-5358, mengeb@oregonstate.edu

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This photograph of a disintegrating adult purple sea star, Pisaster ochraceus, is available at: https://flic.kr/p/nzd81S

West Coast scientists sound alarm for changing ocean chemistry

CORVALLIS, Ore. – The ocean chemistry along the West Coast of North America is changing rapidly because of global carbon dioxide emissions, and the governments of Oregon, California, Washington and British Columbia can take actions now to offset and mitigate the effects of these changes.

That is the conclusion of a 20-member panel of leading West Coast ocean scientists, who presented a comprehensive report on Monday outlining a series of recommendations to address the increase in ocean acidification and hypoxia, or extremely low oxygen levels.

“Ocean acidification is a global problem that is having a disproportionate impact on productive West Coast ecosystems,” said Francis Chan, an Oregon State University marine ecologist and co-chair of the West Coast Ocean Acidification and Hypoxia Science Panel. “There has been an attitude that there is not much we can do about this locally, but that just isn’t true. A lot of the solutions will come locally and through coordinated regional efforts.”

Ocean acidification and hypoxia are distinct phenomena that trigger a wide range of effects on marine ecosystems. They frequently occur together and represent two important facets of global ocean changes that have important implications for Oregon’s coastal oceans.

Among the panel’s recommendations:

  • Develop new benchmarks for near-shore water quality as existing criteria were not developed to protect marine organisms from acidification;
  • Improve methods of removing carbon dioxide from seawater through the use of kelp beds, eel grass and other plants;
  • Enhance coastal ecosystems’ ability to adapt to changing ocean chemistry through better resource management, including marine reserves, adaptive breeding techniques for shellfish, and other methods.

“Communities around the country are increasingly vulnerable to ocean acidification and long-term environmental changes," said Richard Spinrad, chief scientist for the National Oceanic and Atmospheric Administration, and former OSU vice president for research. “It is crucial that we comprehend how ocean chemistry is changing in different places, so we applaud the steps the West Coast Ocean Acidification and Hypoxia Science Panel has put forward in understanding and addressing this issue. We continue to look to the West Coast as a leader on understanding ocean acidification.”

Chan said regional awareness of the impact of changing ocean chemistry started in Oregon. Some of the first impacts were seen about 15 years ago when the state began experiencing seasonal hypoxia, or low-oxygen water, leading to some marine organism die-offs. Then the oyster industry was confronted with high mortality rates of juvenile oysters because of increasingly acidified water. It turns out that Oregon was on the leading edge of a much larger problem.

“It was a wakeup call for the region, which since has spread up and down the coast,” said Chan, an associate professor in the Department of Integrative Biology in OSU’s College of Science.

California responded to this call, and in partnership with Oregon, Washington and British Columbia, convened a panel of scientific experts to provide advice on the issue. The panel worked with federal and state agencies, local organizations and higher education institutions to identify concerns about ocean acidification and hypoxia, then developed a series of recommendations and actions that can be taken today.

“One of the things all of the scientists agree on is the need for better ocean monitoring or ‘listening posts,’ up and down the West Coast,” said Jack Barth, a professor and associate dean in OSU’s College of Earth, Ocean, and Atmospheric Sciences and a member of the panel. “It is a unifying issue that will require participation from state and federal agencies, as well as universities, ports, local governments and NGOs.”

Barth said one such “listening post” has been the Whiskey Creek Shellfish Hatchery in Netarts Bay, Oregon, which was able to solve the die-off of juvenile oysters with the help of OSU scientists George Waldbusser and Burke Hales, who both served on the 20-member panel. Together, they determined that the ocean chemistry changed throughout the day and by taking in seawater in the afternoon, when photosynthesis peaked and CO2 levels were lower, juvenile oysters could survive.

The West Coast is a hotspot for acidification because of coastal upwelling, which brings nutrient-rich, low-oxygen and high carbon dioxide water from deep in the water column to the surface near the coast. These nutrients fertilize the water column, trigger phytoplankton blooms that die and sink to the bottom, producing even more carbon dioxide and lowering oxygen further.

“We’re just starting to see the impacts now, and we need to accelerate what we know about how increasingly acidified water will impact our ecosystems,” said panel member Waldo Wakefield, a research fisheries biologist with NOAA Fisheries in Newport and courtesy associate professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

“There’s a lot at stake. West Coast fisheries are economic drivers of many coastal communities, and the seafood we enjoy depends on a food web that is likely to be affected by more corrosive water.”

Last year, OSU researchers completed the deployment of moorings, buoys and gliders as part of the Endurance Array – a component of the $386 million National Science Foundation-funded Ocean Observatories Initiative, created to address ocean issues including acidification.

These and other ocean-monitoring efforts will be important to inform policy-makers about where to best focus their adaptation and mitigation strategies.

“The panel’s findings provide a road map to help us prepare for the changes ahead,” said Gabriela Goldfarb, natural resource policy adviser to Oregon Gov. Kate Brown. “How Oregon and the West Coast address ocean acidification will inform those confronting this issue around the country and world.”

“With the best scientific recommendations in hand from the science panel, we now have the information on which to base our future management decisions,” added Caren Braby, marine resource manager at the Oregon Department of Fish and Wildlife. “These are practical recommendations natural resource managers and communities can use to ensure we continue to have the rich and productive ecosystem Oregonians depend on for healthy fisheries, our coastal culture and economy.”

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Francis Chan, 541-844-8415, chanft@science.oregonstate.edu;

Jack Barth, 541-737-1607, barth@coas.oregonstate.edu

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oyster

An oyster at Whiskey Creek Shellfish Hatchery

An ancient killer: ancestral malarial organisms traced to age of dinosaurs

CORVALLIS, Ore. – A new analysis of the prehistoric origin of malaria suggests that it evolved in insects at least 100 million years ago, and the first vertebrate hosts of this disease were probably reptiles, which at that time would have included the dinosaurs.

Malaria, a scourge on human society that still kills more than 400,000 people a year, is often thought to be of more modern origin - ranging from 15,000 to 8 million years old, caused primarily by one genus of protozoa, Plasmodium, and spread by anopheline mosquitoes.

But the ancestral forms of this disease used different insect vectors and different malarial strains, and may literally have helped shape animal survival and evolution on Earth, according to George Poinar, Jr., a researcher in the College of Science at Oregon State University.

Poinar suggested in the journal American Entomologist that the origins of this deadly disease, which today can infect animals ranging from humans and other mammals to birds and reptiles, may have begun in an insect such as the biting midge more than 100 million years ago. And in previous work, Poinar and his wife, Roberta, implicated malaria and the evolution of blood-sucking insects as disease vectors that could have played a significant role in the extinction of the dinosaurs.

“Scientists have argued and disagreed for a long time about how malaria evolved and how old it is,” Poinar said. “I think the fossil evidence shows that modern malaria vectored by mosquitoes is at least 20 million years old, and earlier forms of the disease, carried by biting midges, are at least 100 million years old and probably much older.”

Since the sexual reproduction stage of malaria only occurs in insects, Poinar said in the new study that they must be considered the primary hosts of the disease, not the vertebrate animals that they infect with disease-causing protozoa. And he believes the evidence points toward the Gregarinida as a protozoan parasite group that could have been the progenitors of malaria, since they readily infect the insects that vector malaria today.

Understanding the ancient history of malaria evolution, Poinar said, might offer clues to how its modern-day life cycle works, how it evolved, and what might make possible targets to interrupt its transmission through its most common vector, the Anopheles mosquito.

Understanding the evolution of malaria also takes one on a worldwide journey, according to evidence found in insects preserved in amber. Poinar is an international expert in using plant and animal life forms preserved in this semi-precious stone to help learn more about the biology and ecology of the distant past.

Poinar was the first to discover a type of malaria in a 15-20 million-year-old fossil from the New World, in what is now the Dominican Republic. It was the first fossil record of Plasmodium malaria, one type of which is now the strain that infects and kills humans.

Even further back, malaria may have been one of the diseases that arose, along with the evolution of insects, and had a huge impact on animal evolution. In a 2007 book, “What Bugged the Dinosaurs? Insects, Disease and Death in the Cretaceous,” George and Roberta Poinar argued that insects carried diseases that contributed to the widespread extinction of the dinosaurs around the “K-T boundary” about 65 million years ago.

“There were catastrophic events known to have happened around that time, such as asteroid impacts and lava flows,” Poinar said. “But it’s still clear that dinosaurs declined and slowly became extinct over thousands of years, which suggests other issues must also have been at work. Insects, microbial pathogens and vertebrate diseases were just emerging around that same time, including malaria.”

Avian malaria has been implicated in the extinction of many bird species in Hawaii just in recent decades, especially in species with no natural resistance to the disease. Different forms of malaria, which is now known to be an ancient disease, may have been at work many millions of years ago and probably had other implications affecting the outcome of vertebrate survival, Poinar said.

The first human recording of malaria was in China in 2,700 B.C., and some researchers say it may have helped lead to the fall of the Roman Empire. In 2015 there were 214 million cases worldwide, according to the World Health Organization. Immunity does not occur naturally and the search for a vaccine has not yet been achieved.

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Biting midge


Biting midge
with ancestral malaria


Oldest fossil showing Plasmodium malaria
Oldest fossil with
Plasmodium malaria

DNA evidence shows that salmon hatcheries cause substantial, rapid genetic changes

CORVALLIS, Ore. – A new study on steelhead trout in Oregon offers genetic evidence that wild and hatchery fish are different at the DNA level, and that they can become different with surprising speed.

The research, published today in Nature Communications, found that after one generation of hatchery culture, the offspring of wild fish and first-generation hatchery fish differed in the activity of more than 700 genes.

A single generation of adaptation to the hatchery resulted in observable changes at the DNA level that were passed on to offspring, scientists reported.

This research was conducted at Oregon State University in collaboration with the Oregon Department of Fisheries and Wildlife. Scientists say the findings essentially close the case on whether or not wild and hatchery fish can be genetically different.

Differences in survival and reproductive success between hatchery and wild fish have long offered evidence of rapid adaptation to the hatchery environment. This new DNA evidence directly measured the activity of all genes in the offspring of hatchery and wild fish. It conclusively demonstrates that the genetic differences between hatchery and wild fish are large in scale and fully heritable.

“A fish hatchery is a very artificial environment that causes strong natural selection pressures,” said Michael Blouin, a professor of integrative biology in the OSU College of Science. “A concrete box with 50,000 other fish all crowded together and fed pellet food is clearly a lot different than an open stream.”

It’s not clear exactly what traits are being selected for, but the study was able to identify some genetic changes that may explain how the fish are responding to the novel environment in the hatchery.

“We observed that a large number of genes were involved in pathways related to wound healing, immunity, and metabolism, and this is consistent with the idea that the earliest stages of domestication may involve adapting to highly crowded conditions,” said Mark Christie, lead author of the study.

Aside from crowding, which is common in the hatchery, injuries also happen more often and disease can be more prevalent.

The genetic changes are substantial and rapid, the study found. It’s literally a process of evolution at work, but in this case it does not take multiple generations or long periods of time.

“We expected hatcheries to have a genetic impact,” Blouin said. “However, the large amount of change we observed at the DNA level was really amazing. This was a surprising result.”

With the question put to rest of whether hatchery fish are different, Blouin said, it may now be possible to determine exactly how they are different, and work to address that problem. When the genetic changes that occur in a hatchery environment are better understood, it could be possible to change the way fish are raised in order to produce hatchery fish that are more like wild fish. This research is a first step in that direction.

This work was performed using steelhead trout from the Hood River in Oregon. It was supported by the Bonneville Power Administration and the Oregon Department of Fish and Wildlife.

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Michael Blouin, 541-737-2362

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Steelhead


Steelhead trout


Juvenile steelhead trout
Juvenile steelhead

Ancient flowering plant was beautiful - but probably poisonous

CORVALLIS, Ore. – Researchers today announced in the journal Nature Plants the discovery of the first-ever fossil specimens of an “asterid” – a group of flowering plants that gave us everything from the potato to tomatoes, tobacco, petunias and our morning cup of coffee.

But these two 20-30 million-year-old fossil flowers, found perfectly preserved in a piece of amber, came from the dark side of the asterid group – they belong to the genus Strychnos, which ultimately gave rise to some of the world’s most famous poisons, including strychnine and curare.

Poisons that would later find their way into blow-gun weapons, rat control, Sherlock Holmes stories and the movie “Psycho” appear to have had some of their ancestral and biological roots in the prehistoric jungles of what’s now the Dominican Republic, researchers say.

“The specimens are beautiful, perfectly preserved fossil flowers, which at one point in time were borne by plants that lived in a steamy tropical forest with both large and small trees, climbing vines, palms, grasses and other vegetation,” said George Poinar, Jr., a courtesy professor in the College of Science at Oregon State University, and one of the world’s experts on plant and animal life forms preserved in amber.

“Specimens such as this are what give us insights into the ecology of ecosystems in the distant past,” Poinar said.  “It shows that the asterids, which later gave humans all types of foods and other products, were already evolving many millions of years ago.”

Asterids, the researchers noted in this study, are among Earth’s most important and diverse plants, with 10 orders, 98 families, and about 80,000 species. They represent about one-third of all the Earth’s diversity of angiosperms, or flowering plants.

And one ancient genus, which has now been shown to be inherently toxic, existed for millions of years before humans appeared on the planet.

“Species of the genus Strychnos are almost all toxic in some way,” Poinar said. “Each plant has its own alkaloids with varying effects. Some are more toxic than others, and it may be that they were successful because their poisons offered some defense against herbivores.

“Today some of these toxins have been shown to possess useful and even medicinal properties.”

As natural poisons that humans came to understand and use, two extracts from plants in the Strychnos genus ultimately became famous – strychnine and curare.

Strychnine had practical uses for decades as a pesticide, and was often the deadly component of rat poison. But it also captured the imagination of writers, and was used by Norman Bates in the movie “Psycho” to kill his mother and her male companion. In small doses, it can increase mental and muscular activity.

Curare has an even stranger history. Sir Walter Raleigh may have first encountered it in 1596 when he observed poison arrows in South America, where natives also developed the poison in blow-gun darts to paralyze hunted prey. Curare was featured as the murder weapon in one Sherlock Holmes novel, and in lower doses it has been used as a muscle relaxant in surgery.

There are now about 200 species of Strychnos plants around the world, in forms ranging from shrubs to trees and woody climbing vines, mostly in the tropics. They are still being studied for medicinal properties, such as for the treatment of parasitic worm infections and even as drugs to treat malaria.

The discovery of these two fossil flowers, researchers said, suggests that many other related plant families could have evolved in the Late Cretaceous in tropical forests. Their fossil remains, however, still await discovery.

The co-author of this study, Lena Struwe, is an expert on plants in the strychnine family, Loganiaceae, and is a plant biologist at Rutgers University.

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Ancient asterid


Asterid fossil


Asterid flower
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