Mediterranean diet helps reduce effects of stress in animal model, study shows

WAKE FOREST BAPTIST MEDICAL CENTER

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WINSTON-SALEM, N.C. - Nov. 16, 2020 - Even before the pandemic and the presidential election, Americans reported some of the highest perceived levels of stress in the world, according to the American Psychological Association. Not only does stress have negative effects on work and personal relationships, it also increases the risk of many chronic conditions, such as heart disease and Alzheimer's disease, and is associated with higher mortality rates.

But eating a Mediterranean diet may provide a relatively easy way to help lessen the physiological effects of stress and promote healthy aging, according to a new study conducted by researchers at Wake Forest School of Medicine, part of Wake Forest Baptist Health.

Findings from the study, the first preclinical trial to measure the effects of long-term consumption of a Western versus Mediterranean diet on stress under controlled experimental conditions, are published in the current online edition of the journal Neurobiology of Stress.

"It is very difficult to control or reduce stressors in our lives," said Carol A. Shively, Ph.D., professor of pathology and comparative medicine at Wake Forest School of Medicine and principal investigator of the study. "But we do know that we can control our diet, and previous observational studies have suggested that lower perceived stress is associated with high fruit and vegetable consumption.

"Unfortunately, Americans consume a diet rich in animal protein and saturated fat, salt and sugar, so we wanted to find out if that diet worsened the body's response to stress compared to a Mediterranean diet, in which much of the protein and fat come from plant sources."

The researchers studied the effects of the chronic stress of low social status and the acute stress of being socially isolated for 30 minutes in 38 middle-age animals that were fed either a Mediterranean or Western diet. The diets were formulated to closely reflect human diets, with protein and fat derived largely from animal sources in the Western group and primarily from plant sources in the Mediterranean group.

To determine the diets' effect on stress responses, the scientists measured changes in the sympathetic and parasympathetic nervous systems and in the adrenal gland hormone cortisol, in response to acute and chronic stress.

The sympathetic nervous system is involved in the "fight or flight" response and regulates bodily functions such as heart rate and blood pressure. The parasympathetic nervous system has opposite effects that help the body return to a calmer state. High sympathetic nervous system activity can be harmful to health, so maintaining a healthy balance between the two systems is important, Shively said.

Cortisol, the body's main stress hormone, helps the body access resources needed to fight or flee. However, if stress is continuous, cortisol levels stay high and damage tissues.

Compared to animals fed a Western diet, those fed the Mediterranean diet exhibited enhanced stress resilience as indicated by lower sympathetic nervous system and cortisol responses to stress, and more rapid recovery after the stress ended, Shively said.

"Our study showed that the Mediterranean diet shifted the balance toward the parasympathetic nervous system, which is good for health," Shively said. "By contrast, the Western diet increased the sympathetic response to stress, which is like having the panic button on all the time - and that isn't healthy."

As the animals aged over the 31-month study, which is equivalent to about 9 years in humans, the research group noted that sympathetic nervous system activity increased. However, the Mediterranean diet slowed the aging of the sympathetic nervous system.

The study's findings suggest that population-wide adoption of a Mediterranean-like diet may provide a relatively simple and cost-effective intervention to reduce the negative impact of psychological stress on health and delay nervous system aging, Shively said.

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The study was supported by the National Institutes of Health R01HL087103, RF1AG058829, R01HL122393, U24DK097748, and the Wake Forest Claude D. Pepper Older American Independence Center P30AG012332.

Health care workers most at risk for COVID-19

A Rutgers study finds nurses have the highest prevalence of infection

RUTGERS UNIVERSITY

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Health care workers -- particularly nurses -- have a higher prevalence of SARS-CoV-2 infection than non-health care workers, according to researchers at Rutgers, which released baseline results from a large prospective study of participants at Rutgers and affiliated hospitals recruited during the early phase of the COVID-19 pandemic.

The study, published in the journal BMC Infectious Diseases, found that in early spring, the participants most likely to test positive for COVID-19 were nurses, workers taking care of multiple patients with suspected or confirmed COVID-19 and those who worked in a hospital with a higher proportion of infected patients.

As of Nov. 15, 2020, according to the CDC, there were more than 216,000 confirmed COVID-19 cases among health care workers in the United States, leading to at least 799 deaths. The Rutgers study evaluated 546 health care workers with direct patient exposure at two New Jersey hospitals and 283 non-health care workers with no direct patient contact.

At the start of the study in March, 40 health care workers and one non-health care worker tested positive for SARS-CoV-2 infection. Among all participants enrolled, more than 7 percent of health care workers were found to be positive for the novel coronavirus as compared to the very low rates of positive testing among non-health care workers. Also, consistent with disparities observed in the general public, Black and Hispanic participants had more positive test results.

Health care workers who reported caring for five or more patients with suspected or confirmed COVID-19 and those who spent a greater proportion of their time in patients' rooms were more likely to test positive for the infection themselves.

Of the 40 infected health care workers, 25 were nurses. Intensive care unit workers had the lowest rates of infections among the health care workers, possibly due to the more consistent use of personal protective equipment.

"We have all heard about how health care workers are the heroes on the frontlines of this pandemic, but we still don't have solid answers about the risks to health care workers and who is most at risk ," said lead co-author Emily Barrett, an associate professor of biostatistics and epidemiology at Rutgers School of Public Health. "The initial results show that at the beginning of the pandemic, the higher rate of infection observed in urban North New Jersey areas, like Newark, was also reflected in the health care workers serving those communities."

"The baseline data reported here have helped us to monitor the spread of infection and examine risk factors for transmission among health care workers and others," said lead co-author Daniel Horton, an assistant professor of pediatrics at Rutgers Robert Wood Johnson Medical School and assistant professor of epidemiology at Rutgers School of Public Health. "These findings and our ongoing follow-up of study participants have informed local strategies to protect the health care workforce, their families and their patients."

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The study was coordinated by Rutgers Biomedical and Health Sciences, the university's academic health system. Study investigators are also involved in clinical trials and other studies exploring new drug treatments, antibody testing and long-term health tracking to provide insight into how to treat COVID-19 and prevent its spread. The study was funded by the National Center for Advancing Translational Sciences and the National Institute of Allergy and Infectious Diseases at the National Institutes of Health.

Other Rutgers authors include Jason Roy, Maria Laura Gennaro, Andrew Brooks, Jay Tischfield, Patricia Greenberg, Tracy Andrews, Sugeet Jagpal, Nancy Reilly, Jeffrey Carson, Martin Blaser and Reynold Panettieri.

Implementing carbon pricing during the pandemic could help countries recover greener, smarter

PRINCETON UNIVERSITY, WOODROW WILSON SCHOOL OF PUBLIC AND INTERNATIONAL AFFAIRS

Research News

 

PRINCETON, N.J. --Countries across the globe have been struggling to deal with the impact of Covid-19 and its accompanying economic slowdown. As economies "build back better," it may be an opportune time to introduce carbon pricing to tackle climate change, according to new Princeton University policy research.

While endorsed by many economists, carbon pricing has been slower to gain traction because of its potential to shock economies and the difficulty of securing political support for increasing taxes. However, fuel prices are already low and people are buying fewer goods and traveling less, so there could be greater benefits to introducing or strengthening carbon prices, the authors argue in the journal Climate Policy.

Carbon pricing -- whether in the form of taxes or emissions trading -- is an economic approach to account for the environmental costs of emitting greenhouse gases from burning fossil fuels. Carbon taxes typically apply to the producer with increased costs ultimately trickling down to any activity using carbon. For example, oil-extraction companies would be taxed, adding costs to any process that involved burning oil. Emissions-trading schemes set some cap on emissions and permits to emit are traded, but the number of total permits available correspond to that cap.

"When we think about long-term problems like the pandemic or climate change, it's easy to assume that the solutions could conflict since they all require massive resources," said lead author Kian Mintz-Woo, a former postdoctoral research associate in Princeton's University Center for Human Values and the Princeton School of Public and International Affairs (SPIA). "But what we describe in this article is how the context of the coronavirus crisis actually provides a unique opportunity for mutually reinforcing forward-thinking solutions to improve sustainability and wellbeing as countries recover."

Mintz-Woo, who recently joined the Philosophy and Environmental Research Institute at University College Cork, Ireland, added that this research expands on an op-ed co-authored with Princeton Professor Peter Singer published on May 7 by Project Syndicate.

With markets already reorienting to adjust to supply-and-demand shocks brought on by the pandemic, introducing carbon pricing now would result in marginally less disruption and could actually help drive greener economic activity. Placing a price on carbon could prompt industries to move away from more costly fossil-fuel intensive practices and toward long-term economic and environmental sustainability.

"Since carbon pollution already increases health and environmental costs borne by society, forcing those generating the costs to pay for them would lead to fairer production and consumption," Mintz-Woo said.

In the context of low fuel prices over an extended period, as seen in recent months, the researchers suggest that a carbon tax could help stabilize prices and ensure that renewable energy sources -- the prices of which were becoming cost-competitive even before the Covid-19 crisis -- can remain competitive. The researchers say that as economies move toward recovery, a carbon price can drive individuals and firms to adopt less carbon-intensive processes, rather than locking-in unsustainable energy practices that will ultimately require more drastic future corrections.

"Preventing commitment to future emissions is the key," Mintz-Woo said. "But that cannot come at the expense of those who may be at risk for job losses in this transition. Governments should use the revenue to both reduce any regressive effects of the taxation and retrain those who come from industries that could be adversely affected."

The researchers acknowledge that governments are under pressure to prioritize economic recovery from the Covid-19 crisis, so any policy changes with the potential to dampen a stimulus effect could be unpopular. However, they argue that high prices are not the primary obstacle to consumer purchasing; the cause of the economic slowdown has more to do with restricted market activity during the pandemic.

Revenue generated from a carbon price could contribute toward government spending on social safety nets, fund other green priorities to drive innovation and new jobs, or be returned as credits to taxpayers. In all cases, the potential revenue source could be a welcome infusion during the Covid-19 crisis, when regional and national governments face massive fiscal shortfalls which can be expected to grow in the coming months.

"Right now, governments are considering bailouts for carbon-intensive sectors, like the airline industry," Mintz-Woo said. "While it's really hard on employees in that industry right now, government money would be far better spent on clean research and development investments and other strategies to help companies prepare for the future. And that means preparing for employment transitions away from carbon-intensive jobs and towards areas that will be more beneficial to the environment. Carbon pricing can help us do just that."

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The paper, "Carbon Pricing and COVID-19," first appeared in Climate Policy on 15 November.
Additional co-authors on the article are Francis Dennig (Yale-NUS Singapore); Hongxun Liu (Center for Policy Research on Energy and the Environment, Princeton School of Public and International Affairs); and Thomas Schinko (Risk and Resilience Program (RISK), International Institute for Applied Systems Analysis).

A short version of the article's arguments is expected to be released on the blog
https://climatestrategies.wordpress.com.

Computer scientists launch counteroffensive against video game cheaters

Cheat detection system could gracefully kick out cheating players

UNIVERSITY OF TEXAS AT DALLAS

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IMAGE: DR. LATIFUR KHAN, PROFESSOR OF COMPUTER SCIENCE IN THE ERIK JONSSON SCHOOL OF ENGINEERING AND COMPUTER SCIENCE view more 

CREDIT: THE UNIVERSITY OF TEXAS AT DALLAS

University of Texas at Dallas computer scientists have devised a new weapon against video game players who cheat.

The researchers developed their approach for detecting cheaters using the popular first-person shooter game Counter-Strike. But the mechanism can work for any massively multiplayer online (MMO) game that sends data traffic to a central server.

Their research was published online Aug. 3 in IEEE Transactions on Dependable and Secure Computing.

Counter-Strike is a series of games in which players work in teams to counter terrorists by securing plant locations, defusing bombs and rescuing hostages. Players can earn in-game currency to buy more powerful weapons, which is a key to success. Various software cheats for the game are available online.

"Sometimes when you're playing against players who use cheats you can tell, but sometimes it may not be evident," said Md Shihabul Islam, a UT Dallas computer science doctoral student in the Erik Jonsson School of Engineering and Computer Science and lead author of the study, who plays Counter-Strike for fun. "It's not fair to the other players."

In addition to fair play, cheating also can have an economic impact when dissatisfied players leave to play other games, Islam said.

Cheating incidents also can have serious consequences in esports, a fast-growing industry with annual revenues close to $1 billion. Cheating can result in sanctions against teams and players, including disqualification, forfeiture of prize money and a ban on future participation, according to the Esports Integrity Commission based in the United Kingdom.

Detecting cheating in MMO games can be challenging because the data that goes from a player's computer to the game server is encrypted. Previous research has relied on decrypted game logs to detect cheating after the fact. The UT Dallas researchers' approach eliminates the need for decrypted data and instead analyzes encrypted data traffic to and from the server in real time.

"Players who cheat send traffic in a different way," said Dr. Latifur Khan, an author of the study, professor of computer science and director of the Big Data Analytics and Management Lab at UT Dallas. "We're trying to capture those characteristics."

For the study, 20 students in the UT Dallas class Cyber Security Essentials for Practitioners downloaded Counter-Strike and three software cheats: an aimbot, which automatically targets an opponent; a speed hack, which allows the player to move faster; and a wallhack, which makes walls transparent so players can easily see their opponent. The researchers set up a server dedicated to the project so the students' activity would not disrupt other online players.

The researchers analyzed game traffic to and from the dedicated server. Data travels in packets, or bundles, of information. The packets can be different sizes, depending on the contents. Researchers analyzed features, including the number of incoming and outgoing packets, their size, the time they were transmitted, their direction and the number of packets in a burst, which is a group of consecutive packets.

By monitoring the data traffic from the student players, researchers identified patterns that indicated cheating. They then used that information to train a machine-learning model, a form of artificial intelligence, to predict cheating based on patterns and features in the game data.

The researchers adjusted their statistical model, based on a small set of gamers, to work for larger populations. Part of the cheat-detection mechanism involves sending the data traffic to a graphics processing unit, which is a parallel server, to make the process faster and take the workload off the main server's central processing unit.

The researchers plan to extend their work to create an approach for games that do not use a client-server architecture and to make the detection mechanism more secure. Islam said gaming companies could use the UT Dallas technique with their own data to train gaming software to detect cheating. If cheating is detected, the system could take immediate action.

"After detection," Khan said, "we can give a warning and gracefully kick the player out if they continue with the cheating during a fixed time interval.

"Our aim is to ensure that games like Counter-Strike remain fun and fair for all players."

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Other authors of the study include Swarup Chandra PhD'18, a research engineer at Hewlett Packard Enterprise, and UT Dallas computer science doctoral student Bo Dong. Dr. Bhavani Thuraisingham, Founders Chair in Engineering and Computer Science, professor of computer science and executive director of the Cyber Security Research and Education Institute at UT Dallas, is senior author of the study.

The research was funded by the National Science Foundation, Air Force Office of Scientific Research, National Security Agency, IBM and Hewlett-Packard Development Co.

OHIO's Franz publishes study on strategies hospitals adopt to address opioid epidemic

OHIO UNIVERSITY

Research News

 

While the world's attention to public health remains focused on COVID-19, Berkeley Franz, Ph.D., assistant professor at the Ohio University Heritage College of Osteopathic Medicine, continues to focus her attention on one of the largest public health crises in the United States today - the opioid epidemic.

Franz, along with Cory Cronin, Ph.D., assistant professor in OHIO's College of Health Sciences and Professions, and José Pagán, Ph.D., professor of public health policy and management at New York University, co-authored the article, "What Strategies Are Hospitals Adopting to Address the Opioid Epidemic? Evidence From a National Sample of Nonprofit Hospitals," to identify what hospitals are doing to combat the opioid epidemic and how they could better address these problems in communities.

The study led by Franz is published in Public Health Reports, the official journal of the Office of the U.S. Surgeon General and the U.S. Public Health Service.

"Prior to the COVID-19 pandemic, the opioid epidemic was the most vexing health problem," Franz said. "High rates of addiction were cited as one of the main reasons that American life expectancy declined in multiple years, something we rarely see. At the same time, opioid misuse increased to be the greatest causes of preventable death. This study shows that hospitals can play a clear and important role in implementing interventions and effectively treating patients, especially if they are willing to do so on site."

This study is part of ongoing research Franz is doing to understand whether hospitals are addressing the most critical public health needs in their communities. She is also studying institutional barriers to adopting new programs to address opioid misuse, including the presence of bias/stigma among health care professionals.

Through their research, Franz, Cronin and Pagán found that hospitals often don't do evidence-based programs despite evidence that treating the patient at the hospital rather than through a referral leads to more effective treatment and reduces death from subsequent overdoses.

"With opioid misuse, people often end up in hospitals for care, which is a great place to address other, secondary health consequences that come from the misuse," Franz explained. "Aside from an actual overdose itself, people can get infections at the injection site, heart and skin infections, infectious diseases linked to intravenous drug use and more. By taking care of these individuals in a hospital setting, medical professionals can also address these issues as well as introduce treatment for the underlying substance use disorder."

To compile data, the researchers analyzed data from a 20% sample of all U.S. hospitals to determine what they were doing to address opioid abuse.

The researchers looked at whether hospitals offered specific kinds of services - and specifically whether the hospitals were directly addressing the issue or redirecting patients to primary care or other outpatient care.

"While individual health needs assessments and implementation strategies are publicly available, our hope is that by aggregating strategies and trends, we can provide a snapshot of the overall picture, which may be helpful to decision makers in health care organizations or public agencies," Cronin said.

The study shows that nonprofit hospitals invest in clinical strategies and risk education, but they could do more by initiating medication-assisted treatment at the hospitals and adopting harm reduction initiatives, such as distributing naloxone or offering syringe exchanges.

"We have created a great partnership between Ohio University and New York University researchers interested in the contribution of hospitals to improve the health of our communities," Pagán said. "I am very lucky to have had the opportunity to work with this great team and bring awareness to the important leadership role hospitals play in our communities to help reduce opioid abuse."

Pagán added that state support is important, as hospitals are more likely to adopt harm reduction programs and other strategies in states that take the lead encouraging the use of these strategies.

Although some hospitals are adopting evidence-based strategies to address opioid misuse, the pandemic is affecting how hospitals can implement such programs effectively. For instance, many hospitals are currently focused on fighting COVID 19, so they may have fewer opportunities to offer substance abuse services. At the same time, the added societal stress of the pandemic can actually exacerbate substance misuse. Also, some hospitals do not offer direct services for those who misuse substances.

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Franz is also holder of the Heritage Career Development Faculty Endowed Fellowship in Population Health, Osteopathic Heritage Foundation Ralph S. Licklider, D.O., Research Endowment, which supported this research study through providing funding support to train/work with Jose A. Pagán and also provided direct funds for carrying out the research itself. 

 

Deafening insects mask true biodiversity assessed via acoustic surveys in Japan

TRINITY COLLEGE DUBLIN

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VIDEO: SAMUEL ROSS EXPLAINS THE RESEARCH view more 

https://www.eurekalert.org/multimedia/pub/248959.php?from=484134

CREDIT: TRINITY COLLEGE DUBLIN AND OKINAWA INSTITUTE OF SCIENCE AND TECHNOLOGY GRADUATE UNIVERSITY

A collaborative team of ecologists, led by those from Trinity College Dublin, has been using recordings of animal noises to assess biodiversity in sub-tropical Japan. The team assessed how effective these acoustic surveys were for pinpointing Okinawa's wild and wonderful fauna in different sonic conditions--and discovered that the incessant choruses of the local cicadas disguise the true diversity of the region.

The work, just published in the journal Ecological Indicators, underlines the great potential that acoustic surveys have for characterising the biodiversity of habitats while also highlighting some major potential pitfalls.

Many scientists believe we are now living through the sixth mass extinction in Earth's history, which has largely been driven by human actions and our exploitation of the environment, but there is general consensus that it is not too late to halt declines in biodiversity if we act now. However, we need to know which species (and how many) are present in any given habitat before designing conservation programmes.

Acoustic surveys

Acoustic surveys--simple audio recordings of the animal sounds in a habitat--offer the potential to record large volumes of data. They can do this relatively cheaply and easily, given that recording devices can be left unattended once set up. This technique also means researchers need not spend lengthy periods in unhospitable or dangerous habitats, species are more likely to be accounted for as they won't be scared away by human presence, and the data can be very sensitive as each species makes unique sounds.

However, the new research shows that consideration must be given to ambient conditions, with the time of day, season, and proximity to urban areas and human activity all likely to interfere to varying extents with the recordings, such that some species cannot be heard. Interestingly, on the sub-tropical island of Okinawa off the coast of Japan, it is the incessant noise of the cicada insects that have the biggest impact in masking the hoots, clicks and chirps of hundreds of native animals.

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A bird in Okinawa.

Lead author of the study, Samuel Ross, is a PhD Candidate in Trinity's School of Natural Sciences. He said:

"In total, we used about 230 hours of sound recordings from a wide range of habitats across Okinawa to gain insights into the biodiversity of the region, to characterise how it changes near urban areas, and most importantly, to assess how effective the various audio recording and assessment techniques are in extracting reliable information."

"As you'd expect the weather is important, with heavy winds and rain affecting the information we can get from recordings, and human noise pollution is also problematic. However, it's cicadas that really impact the quality of such assessments during Okinawa's summer months."

To date, most bio-acoustic surveys have been conducted in the Tropics but the field is developing quickly and these monitoring techniques will prove useful in Ireland, which provides homes to a number of iconic, endangered animals.

Many of Ireland's creatures have a cultural significance and the ability to soothe and inspire, while other research is opening our eyes to the power of the acoustic environment in influencing mental health.

Samuel Ross added:

"These methods are still relatively new and the prospect that we can monitor biodiversity using only audio recording equipment is really exciting. I see this as the next frontier in assessing the state of the world's ecosystems."

The study was led by Samuel Ross and Ian Donohue, Associate Professor in Zoology, at Trinity, working closely with colleagues at the Okinawa Institute of Science and Technology (OIST), including Professor Evan Economo and Dr Nick Friedman, who run an island-wide project to monitor Okinawa's ecosystems using sound.

Dr Friedman added:

"The forests in Okinawa are really noisy when the cicadas are out. The sound they make is so loud, it's at least annoying if not painful. It conceals a lot of different species that are in the forest because they don't really bother calling to each other while the cicadas are going. Knowing this helps us strategise how to use soundscape recordings to measure biodiversity or track the health of an ecosystem."

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A cicada in Okinawan forest

People in developing countries eat less bushmeat as they migrate from rural to urban areas

PRINCETON UNIVERSITY, WOODROW WILSON SCHOOL OF PUBLIC AND INTERNATIONAL AFFAIRS

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IMAGE: THE YELLOW-FOOTED TORTOISE (CHELONOIDIS DENTICULATUS), ALSO KNOWN AS THE BRAZILIAN GIANT TORTOISE, CAN BE FOUND IN THE AMAZON BASIL OF SOUTH AMERICA. (PHOTO CREDIT: THAIS MORCATTY) view more 

CREDIT: THAIS MORCATTY

PRINCETON, N.J.-- People around the world, especially in developing countries in Africa, Asia, and South America, consume wild game, or bushmeat, whether out of necessity, as a matter of taste preference, or, in the case of particularly desirable wildlife species, to connote a certain social status. Bushmeat consumption, however, has devasted the populations of hundreds of wildlife species and been linked to the spread of zoological diseases such as the Ebola virus.

New Princeton University research finds that when people in developing countries move from rural areas to cities, they consume less bushmeat over time, perhaps because other sources of animal protein are more readily available. They also found that children in urban areas generally have less of a taste for wild game than their parents. In the long term, this could be good news for conservation.

The researchers traveled to Brazil -- one of many countries worldwide experiencing a dramatic migration from rural to urban areas -- and interviewed thousands of adults and children about their wildlife consumption habits.

The study, published in the journal Conservation Biology, is among the first to explore how the consumption of wildlife changes as countries become increasingly urbanized. The results have profound implications for the rapidly growing wildlife trade, which is a multi-billion-dollar industry that threatens human health, drives species extinction, and damages ecosystems.

"In the Amazon, as in most developing countries, people are leaving rural areas and moving into cities. We find -- for whatever reason -- they are reducing their consumption of wild animals over time, providing a needed break for overhunted wildlife," said study co-author David Wilcove, professor of ecology and evolutionary biology and public affairs and the High Meadows Environmental Institute.

"A decline in per capita consumption of wild animals by urban residents gives us hope that pressure on hunted species may decrease over time. At the same time, we don't know whether this decline will be large enough to compensate for an increasing human population in urban areas," said Willandia Chaves, the lead author of the study, who worked on the project as a postdoctoral researcher at Princeton and is now an assistant professor in the Department of Fish and Wildlife Conservation at Virginia Tech.

Wilcove and Chaves conducted the study with Denis Valle of the University of Florida, Aline S. Tavares of the Universidade Federal do Amazonas, and Thais Q. Morcatty of Oxford Brookes University.

The researchers surveyed six small towns, three large towns, and Manaus, the largest city in the Amazon Basin. This included 1,356 households and 2,776 school-age children. They studied the consumption of imperiled tortoises and freshwater turtles, as they are among the top five most consumed and traded species in urban areas in the Amazon. An estimated 1.7 million turtles were eaten in northwestern Brazil in 2018.

While subsistence hunting is permitted, most wildmeat consumption in Brazil is illegal. Moreover, the turtle species that were being consumed where this study took place are highly endangered. For this reason, the researchers had to design a survey that would allow interviewees to honestly answer questions without implicating themselves.

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The yellow-spotted river turtle was the most consumed throughout the Brazilian regions surveyed by Princeton University researchers.

To do this, they used dominoes. The head of each household (whether male or female) was asked a series of questions about their consumption of turtles (illegal) versus cornmeal (legal).

When asked, "Do you consume this item in your house?" respondents would randomly choose a domino from a bag: one dot represented cornmeal, and two dots for turtles. Because the researchers knew the ratio of one-dot to two-dot dominoes in the bag, they could calculate the consumption rates of turtles while protecting participants' responses by not linking the behavior to an individual participant.

While the domino approach is not new, it has rarely been employed in conservation studies, making this study more cutting-edge. "It's also exciting because it gives us much more reliable answers about sensitive activities than direct questioning does," Wilcove said.

Next, the researchers randomly selected 49 middle and high schools (11 in Manaus, 13 in large towns, and 25 in small towns) to study any generational differences in how much they liked and consumed bushmeat compared to adults. At each school, they randomly selected four classrooms and asked the schoolchildren to complete an anonymous questionnaire, with parental consent. This accounted for 2,700 students in 146 classrooms, and schoolchildren varied from 11 to 18 years in age.

First, the researchers found people generally consumed fewer turtles in larger urban areas. This could be because turtles cost more in larger cities than in small towns, and law enforcement also is likely stronger in larger urban centers. In small towns, on the other hand, the rates of turtle consumption are much higher, perhaps because people living there have ready access to wilder areas where the turtles live or perhaps because enforcement of wildlife laws is lax.

Second, children in urban areas are generally less likely to consume turtles than their parents. Social eating norms could play a role. If other children say it's "uncool" to eat turtles, then other kids might follow suit, or vice versa. Perhaps children consider the conservation implications of eating wildlife. Or perhaps it's simply because children's tastebuds haven't been fully developed. The researchers said more studies are needed to understand children's motivations.

"Is it a taste they will develop later in life, like children refusing to eat vegetables, or is it a lifelong switch?" Wilcove said. "We don't know yet, but the answer will mean a lot to the future of wildlife in the Amazon."

The researchers estimated that the overall consumption of endangered turtles in Amazonas state, the largest state in the Brazilian Amazon, is a very alarming 1.7 million turtles per year. Therefore, programs aimed at reducing consumption of illegal wildlife are urgently needed.

Certain towns seem to be "hotspots" for bushmeat consumption, so conservation efforts in those areas could be particularly important. Importantly, conservation education focused on schoolchildren, including increasing awareness regarding the plight of Amazonian turtles, could have long-term benefits if children forgo eating turtles as they become adults.

"Conservation efforts have focused on things like creating protected areas, working with rural communities to better manage wildlife, and improving enforcement - all important actions. However, unless we also target urban demand for wildlife, we will not be able to effectively address this issue," Chaves said.

"The bushmeat trade, both domestic and international has emerged as a massive threat to biodiversity, comparable to habitat destruction for some places. Yet, our knowledge of what drives this trade and how those drivers may change in the future is surprisingly weak. Until we better understand these issues, we are poorly equipped to solve this growing threat to wildlife," Wilcove said.

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The paper, "Impacts of rural to urban migration, urbanization, and generational change on consumption of wild animals in the Amazon," first appeared in Conservation Biology on Oct. 30, 2020. This research was funded by the High Meadows Foundation.

CAPTION

These yellow-footed tortoises have been captured for human consumption.

Paleontologists uncover three new species of extinct walruses in Orange County

Study gives insight to tusk evolution of the marine mammal

TAYLOR & FRANCIS GROUP

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IMAGE: MAP & SKULLS view more 

CREDIT: JOURNAL OF VERTEBRATE PALEONTOLOGY

Millions of years ago, in the warm Pacific Ocean off the coast of Southern California, walrus species without tusks lived abundantly.

But in a new study, Cal State Fullerton paleontologists have identified three new walrus species discovered in Orange County and one of the new species has "semi-tusks" -- or longer teeth.

The other two new species don't have tusks and all predate the evolution of the long iconic ivory tusks of the modern-day walrus, which lives in the frigid Arctic.

The researchers describe a total of 12 specimens of fossil walruses from Orange, Los Angeles and Santa Cruz counties, all estimated to be 5 to 10 million years old. The fossils represent five species, with two of the three new species represented by specimens of males, females and juveniles.

Their research, which gives insights on the dental and tusk evolution of the marine mammal, was published today in the Journal of Vertebrate Paleontology.

Geology graduate Jacob Biewer, and his research adviser James F. Parham, associate professor of geological sciences, are authors of the study, based on fossil skull specimens.

Parham and Biewer worked with Jorge Velez-Juarbe, an expert in marine mammals at the Natural History Museum of Los Angeles County, who is a co-author of the paper. Velez-Juarbe is a former postdoctoral scholar in Parham's lab and has collaborated on other CSUF fossil research projects. Parham is a research associate at the museum, which provides research opportunities for him and his students.

The researchers teamed to study and describe the anatomy of the specimens, most of which are part of the museum's collection.

"Orange County is the most important area for fossil walruses in the world," said Biewer, first author of the paper who conducted the research for his master's thesis. "This research shows how the walruses evolved with tusks."

Extinct Walrus Species Get Names

Today, there is only one walrus species and its scientific name is Odobenus.

For the new species found in Orange County, the researchers named the semi-tusked walrus, Osodobenus eodon, by combining the words Oso and Odobenus. Another is named Pontolis kohnoi in honor of Naoki Kohno, a fossil walrus researcher from Japan. Both of these fossils were discovered in the Irvine, Lake Forest and Mission Viejo areas.

Osodobenus eodon and Pontolis kohnoi are both from the same geological rock layer as the 2018 study by Parham and his students of another new genus and species of a tuskless walrus, Titanotaria orangensis, named after CSUF Titans. These fossils were found in the Oso Member of the Capistrano Formation, a geological formation near Lake Forest and Mission Viejo.

The third new walrus species, Pontolis barroni, was found in Aliso Viejo, near the 73 Toll Road. It is named after John Barron, a retired researcher from the U.S.Geological Survey and world expert on the rock layer where the specimens were found, Parham said.

Analysis of these specimens show that fossil walrus teeth are more variable and complex than previously considered. Most of the new specimens predate the evolution of tusks, Parham said.

"Osodobenus eodon is the most primitive walrus with tusk-like teeth," Parham said. "This new species demonstrates the important role of feeding ecology on the origin and early evolution of tusks."

Biewer explained that his work focused on getting a better understanding of the evolutionary history of the walrus in regards to its teeth.

"The importance of dental evolution is that it shows the variability within and across walrus species. Scientists assumed you could identify certain species just based on the teeth, but we show how even individuals of the same species could have variability in their dental setup," said Biewer, who earned a master's degree in geology in 2019.

"Additionally, everyone assumes that the tusks are the most important teeth in a walrus, but this research further emphasizes how tusks were a later addition to the history of walruses. The majority of walrus species were fish eaters and adapted to catching fish, rather than using suction feeding on mollusks like modern walruses."

Biewer, now a paleontologist in the Modesto area, also examined whether climate changes in the Pacific Ocean had an impact on ancient walruses. His work suggests that a rise in water temperature helped to boost nutrients and planktonic life, and played a role in the proliferation of walruses about 10 million years ago, which may have contributed to their diversity.

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For the fossil walrus research project, geology graduate Jacob Biewer spent hours in the lab measuring and describing the walrus bones.

"I sat many hours with a handy caliper taking notes on the lengths of teeth and width of skulls, among many other measurements," he said. "Describing bones is much more in depth and meticulous than it sounds. There are traits that the bones of each walrus species have -- the size, shape and number of teeth. I recorded how the bones are different from, or similar to, other extinct walrus species."

Biewer, a paleontologist who lives in Modesto, noted that despite the pandemic, he and Parham worked on the scientific paper with 300 miles of social distancing.

Completing his first journal publication, based on his master's work, and conducting the research project helped him to understand scientific methods and techniques that he now uses in his career, where he monitors construction sites for paleontological resources. He also teaches undergraduate geology courses at Cal State Stanislaus, where he earned a bachelor's degree in geology, and is considering pursuing a doctorate.

"The experiences I had in conducting this research, especially the presentations at national paleontological conferences, led to a big increase in my confidence in my scientific abilities," Biewer said. "I credit my time working with Dr. Parham directly to the achievements in my current employment -- from the skills he imparted to the doors he helped open."

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