It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Friday, November 22, 2024
Overthinking what you said? It’s your ‘lizard brain’ talking to newer, advanced parts of your brain
Findings have implications for one day treating psychiatric conditions such as anxiety and depression
Study sought to better understand how humans evolved to become skilled at thinking about others
Newer parts of the brain that support social interactions are connected to and in constant communication with the ancient amygdala
First study to map with fMRI never-before-seen details of the brain’s social cognitive network
CHICAGO --- We’ve all been there. Moments after leaving a party, your brain is suddenly filled with intrusive thoughts about what others were thinking. “Did they think I talked too much?” “Did my joke offend them?” “Were they having a good time?”
In a new Northwestern Medicine study, scientists sought to better understand how humans evolved to become so skilled at thinking about what’s happening in other peoples’ minds. The findings could have implications for one day treating psychiatric conditions such as anxiety and depression.
“We spend a lot of time wondering, ‘What is that person feeling, thinking? Did I say something to upset them?’” said senior author Rodrigo Braga. “The parts of the brain that allow us to do this are in regions of the human brain that have expanded recently in our evolution, and that implies that it’s a recently developed process. In essence, you’re putting yourself in someone else’s mind and making inferences about what that person is thinking when you cannot really know.”
The study found the more recently evolved and advanced parts of the human brain that support social interactions — called the social cognitive network — are connected to and in constant communication with an ancient part of the brain called the amygdala.
Often referred to as our “lizard brain,” the amygdala typically is associated with detecting threats and processing fear. A classic example of the amygdala in action is someone’s physiological and emotional response to seeing a snake: startled body, racing heart, sweaty palms. But the amygdala also does other things, Braga said.
“For instance, the amygdala is responsible for social behaviors like parenting, mating, aggression and the navigation of social-dominance hierarchies,” said Braga, an assistant professor of neurology at Northwestern University Feinberg School of Medicine. “Previous studies have found co-activation of the amygdala and social cognitive network, but our study is novel because it shows the communication is always happening.”
Within the amygdala, there’s a specific part called the medial nucleus that is very important for social behaviors. This study was the first to show the amygdala’s medial nucleus is connected to newly evolved social cognitive network regions, which are involved in thinking about other people. This link to the amygdala helps shape the function of the social cognitive network by giving it access to the amygdala’s role in processing emotionally important content.
This was only possible because of functional magnetic resonance imaging (fMRI), a noninvasive brain-imaging technique that measures brain activity by detecting changes in blood oxygen levels. A collaborator at the University of Minnesota and co-author on the study, Kendrick Kay, provided Braga and co-corresponding author Donnisa Edmonds with fMRI data from six study participants’ brains, as part of the Natural Scenes Dataset (NSD). These high-resolution scans enabled the scientists to see details of the social cognitive network that had never been detected on lower-resolution brain scans. What’s more, they were able to replicate the findings up to two times in each individual.
“One of the most exciting things is we were able to identify network regions we weren’t able to see before,” said Edmonds, a neuroscience Ph.D. candidate in Braga’s lab at Northwestern. “That’s something that had been underappreciated before our study, and we were able to get at that because we had such high-resolution data.”
Potential treatment of anxiety, depression
Both anxiety and depression involve amygdala hyperactivity, which can contribute to excessive emotional responses and impaired emotional regulation, Edmonds said. Currently, someone with either condition could receive deep brain stimulation for treatment, but since the amygdala is located deep within the brain, directly behind the eyes, it means having an invasive, surgical procedure. Now, with this study’s findings, a much less-invasive procedure, transcranial magnetic stimulation (TMS), might be able to use knowledge about this brain connection to improve treatment, the authors said.
“Through this knowledge that the amygdala is connected to other brain regions — potentially some that are closer to the skull, which is an easier region to target — that means people who do TMS could target the amygdala instead by targeting these other regions,” Edmonds said.
The study is titled, “The human social cognitive network contains multiple regions within the amygdala.” Other Northwestern co-authors include Christina Zelano, Joseph J. Salvo, Nathan Anderson, Maya Lakshman and Qiaohan Yang.
The human social cognitive network contains multiple regions within the amygdala
Article Publication Date
22-Nov-2024
From food crops to cancer clinics: Lessons in extermination resistance
Borrowing principles from pest management, ASU researchers aim to extend survival rate, quality of life for cancer patients
Arizona State University
image:
Despite significant strides in cancer research and therapy, the disease continues to kill roughly 10 million people a year worldwide. A new approach to the disease draws on techniques long used by farmers to control insect pests. The resulting method — known as "adaptive therapy" — seeks to manage, rather than eradicate cancer cells, transforming cancer into a disease patients can live with, but not die from.
Just as crop-devouring insects evolve to resist pesticides, cancer cells can increase their lethality by developing resistance to treatment. In fact, most deaths from cancer are caused by the evolution of therapeutic resistance.
In a new review, Arizona State University researchers, working with colleagues around the world, explore how established agricultural pest management strategies could be adapted to address cancer therapy. The pioneering method opens new possibilities for controlling drug resistance and improving patient survival.
The research, which appears in the current issue of the journal Cancer Research, explores 10 pest management principles that could be adapted to treat cancer.
The approach represents a paradigm shift, with an emphasis on managing cancer as a chronic condition rather than seeking complete eradication in cases where curing the disease is unlikely. Clinicians are just beginning to apply these strategies, in a treatment called adaptive therapy.
Drawing from pest management opens a new avenue of cancer research and treatment for a disease that now kills nearly 10 million people worldwide each year, according to the World Health Organization (WHO).
“We’ve been treating cancer as if it doesn’t evolve in response to what we do to it. It is time that we take that evolution seriously, guiding it rather than succumbing to it,” says Carlo Maley, co-corresponding author of the new study.
In the 1940s, a central obstacle to effective cancer therapy was already evident to researchers. The cause was the evolution of treatment-resistant cells that could not be killed through existing cancer-fighting drugs. Some 40 years earlier, farmers faced an analogous situation with the development of pesticide-resistant insects, which, left unchallenged, could overwhelm crops.
Drug resistance, a major cause of cancer treatment failure, occurs when therapies inadvertently select for the survival of drug-resistant cancer cells — similar to how pesticides can lead to resistant pests.
When resistance is "selected," cancer cells or insects with resistant traits to treatment or pesticides, respectively, survive and reproduce, while the others are eliminated. Over time, resistant insects or cancer cells dominate. These resistant populations then proliferate, making treatment less effective and more difficult to manage.
Agricultural techniques inspire improved cancer treatment
A suite of agricultural techniques called integrated pest management combines biological, chemical and mechanical controls to sustainably manage pests. Researchers hope to apply ten principles adapted from these techniques in revolutionizing cancer research and treatment.
The techniques include:
Prevention first: Optimizing patient care and modifying the environment to create conditions that are less favorable for cancer cell growth.
Continuous monitoring: Using advanced tools like liquid biopsies to track tumor progression and resistance markers in real time.
Only treat when necessary: Identifying specific thresholds for treatment to minimize unnecessary drug use.
Adaptive treatment: Rotating therapies and adjusting doses based on tumor response to maintain long-term control.
Minimal impact: Selecting treatments with fewer side effects and lower toxicity.
Nonchemical approaches: Incorporating methods such as surgery and immunotherapy to reduce reliance on toxic drugs.
Dose optimization: Using the lowest effective drug doses to slow resistance evolution.
Cross-resistance reduction: Avoiding repeated use of drugs with similar mechanisms of action.
Long-term success metrics: Focusing on survival and quality of life rather than complete eradication of the disease.
Forecasting outcomes: Using predictive models to anticipate tumor behavior and refine treatment plans.
The approach could help overcome treatment resistance that occurs with existing cancer therapies, whether they rely on a single drug or multiple.
The applicability of adaptive therapy to all forms of cancer offers a broad framework for advancing oncology. For example, colorectal cancer, which has multiple treatment options but poor outcomes in the late stages, is an ideal candidate for clinical trials of this approach.
To maximize the potential of the new approach, the researchers emphasize the importance of personalized medicine. Continuous genomic profiling and liquid biopsies during therapy, for example, are powerful tools for tailoring cancer treatments to individual patients. By analyzing changes in tumor mutations and monitoring cancer biomarkers in bodily fluids, these techniques can help oncologists know when to change tactics and slow the evolution of drug-resistant cells while minimizing toxic side effects.
Adaptive therapy in action
In an earlier study — one of the first of its kind — Maley, first author Sareh Seyedi and their colleagues applied adaptive therapy to a preclinical model of a stubbornly resistant form of breast cancer in mice.
Unlike standard cancer treatments that aim to eliminate as many cancer cells as possible using maximum tolerated doses, adaptive therapy uses lower or intermittent doses to keep tumor growth under control. The approach exploits competition between drug-sensitive and drug-resistant cancer cells to prolong survival and reduce treatment resistance.
The researchers found that by alternating or modulating the doses of two anti-cancer drugs, they could significantly improve survival times compared with traditional therapy. The method also used lower cumulative drug doses, reducing toxicity while achieving better outcomes.
The researchers envision a future where adaptive therapy becomes a cornerstone of cancer care. Ongoing preclinical studies aim to validate these principles, and clinical trials will follow to evaluate their effectiveness in patients with advanced cancers.
In addition to ASU colleagues, Maley is joined by national and global researchers from Mayo Clinic; University of Arizona; North Carolina State University; University of California Santa Barbara; The Institute of Cancer Research; The Royal Marsden Hospital; Research Casting International; Istanbul University; and University of Lausanne.
Gwendolyn Purifoye, assistant professor of racial justice and conflict transformation in the Keough School of Global Affairs at the University of Notre Dame.
Credit: Photo by Peter Ringenberg/University of Notre Dame
Black men on buses and trains — whether as passengers or transit workers — face hostile encounters that threaten their sense of safety and well-being, according to a new study by a Keough School of Global Affairs sociologist. By reinforcing racist tropes that they are dangerous or invisible, these encounters can also erode Black men’s sense of dignity and self-worth.
“Black men who want to go to work, school, appointments, visit others, or do any of the other things that people use public transport for, find the experience to be degrading rather than liberating,” said Gwendolyn Purifoye, assistant professor of racial justice and conflict transformation in the Keough School at the University of Notre Dame. “Any hostile encounter in a public space is stressful, but it’s magnified when you are trapped in a space until a vehicle stops.”
Purifoye’s study, co-authored with Derrick Brooms of Morehouse College, was published in the journal Sociology of Race and Ethnicity.
The researchers conducted ethnographic observations on Chicago-area buses and trains between 2010 and 2022, choosing routes that, according to census data, traversed racially and economically diverse areas of the city and suburbs, including downtown Chicago. They traveled at varied times of day and amid diverse weather conditions.
The researchers observed repeated avoidance of Black male passengers by non-Black passengers, which included behaviors such as ignoring a request for directions, moving away or averting eye contact. They also noted surveillance behaviors by authority figures such as police in train stations.
“Being treated as undesirable or as a cause for fear is harmful to Black men, especially because these incidents often play out in front of other people,” said Purifoye, who is a core faculty member of the Keough School’s Kroc Institute for International Peace Studies. “Black men are simultaneously hyper-visible and invisible — visible as potential problems yet invisible as citizens with rights, as human beings with feelings or as persons deserving civility in public spaces.”
The researchers also found that Black male transit personnel faced repeated hostile behaviors such as challenges to their authority and criticism for doing their jobs, especially during large-scale special events such as parades, concerts and sporting events.
“Black men’s status as transit personnel or security does not shield them from racial animus,” Purifoye said. “These types of stressors in everyday life not only have implications for their health and well-being but also can impact their dispositions, relationships and sense of self, which in turn impacts their families and communities.”
Purifoye has shared the study’s findings with Chicago’s Regional Transportation Authority. She is a member of its steering committee that works to implement transit service that is safer, more frequent, reliable and affordable for riders. Based on study results, Purifoye recommends that Chicago’s transit boards adopt policies that add or increase security for transit personnel, regardless of their routes, and provide more funding for security. Purifoye also advises adopting clear policies that protect all passengers and personnel from any form of harassment, she said, while ensuring that policies do not include measures — such as hyper-surveillance or police dogs — that have historically been used against Black populations.
Purifoye said the study revealed a need for further research on how negative interactions on public transportation inform conditions that leave Black men at risk in public. The research was funded by the Midwest Sociological Society and is part of a larger ongoing project that examines social interactions on public transportation across race, class and gender groups.
Photo by Chicago Transit Authority via Flickr Creative Commons
Without Risk Reduction: How Black Men’s Well-being and Humanity Are Compromised in Mobile Public Spaces
Race-blind college admissions harm diversity without improving quality
Cornell University
ITHACA, N.Y. – A new study by Cornell University researchers finds that ignoring race leads to an admitted class that is much less diverse, but with similar academic credentials.
The team used data from an unnamed university to simulate the impacts of the 2023 Supreme Court ruling in Students for Fair Admissions (SFFA) v. Harvard, which prohibits colleges and universities from considering race in admissions. They found that the number of top-ranked applicants who identified as underrepresented minorities (URM) dropped by 62% when removing race as a factor from the school’s applicant-ranking algorithm. At the same time, the test scores of top-ranked applicants did not meaningfully increase.
Jinsook Lee and Emma Harvey, both doctoral students in the field of information science and co-first authors, presented the study, “Ending Affirmative Action Harms Diversity Without Improving Academic Merit,” at the ACM Conference on Equity and Access in Algorithms, Mechanisms, and Optimization (EAAMO ’24).
In the new study, the researchers started by building an AI-based ranking algorithm for the university, which they trained on past admissions decisions to predict the likelihood of a candidate’s acceptance based on their common application. Then they retrained the algorithm without features related to race and rescored the applicants to see how the recommendations changed.
“There's a huge drop in the URM students when you look at the top-ranked pool of applicants,” Lee said. In the original algorithm, 53% of the top group consisted of URM students, which is similar to the composition of the admitted class before the SFFA ruling. After they removed race, the top-ranked group had only 20% URM students.
Taking race out of the equation did result in a tiny increase in the average standardized test scores among the top-ranked students. But the change was negligible – equivalent to the difference between scoring a 1480 and a 1490 on the SAT.
Additional analysis showed that the subset of qualified students in the top-ranked pool under the original algorithm was somewhat arbitrary, because there were so many excellent applicants – the ranking changed substantially when the algorithm was trained with different random subsets of the data. But the rankings became even more arbitrary when race was removed from consideration.
The researchers received support from the National Science Foundation, the Amazon Research Award, the Graduate Fellowships for STEM Diversity, the Urban Tech Hub at Cornell Tech and a seed grant from the Cornell Center for Social Sciences.
For additional information, read this Cornell Chroniclestory.
Cornell University has dedicated television and audio studios available for media interviews.
Ending Affirmative Action Harms Diversity Without Improving Academic Merit
Study finds health disparities in PFAS levels linked to drinking water, food access and industrial pollution
Researchers from the Keck School of Medicine of USC found that certain neighborhood factors were associated with higher levels of PFAS in the blood of Southern California residents, which increases the risk for disease.
Keck School of Medicine of USC
Evidence is mounting on the health problems linked to per- and polyfluoroalkyl substances (PFAS), a group of manufactured chemicals used in consumer products that accumulate in the body and take a very long time to break down. These substances increase risk for a number of medical concerns, including cancer, liver damage and fertility issues.
In a study funded in part by the National Institutes of Health and the USC President’s Sustainability Research Initiative, researchers from the Keck School of Medicine of USC explored whether drinking water, food access and industrial pollution were linked to differences in blood levels of PFAS among 446 Southern California residents. It is one of the first studies to analyze PFAS in relation to certain neighborhood factors, including food access and proximity to Superfund sites—areas designated by the U.S. Environmental Protection Agency (EPA) as contaminated with toxic substances.
“Instead of placing the burden on individuals to avoid PFAS, we’re looking at neighborhood factors beyond their control. How can we improve our neighborhood environments to reduce PFAS and the associated disease risk?” said first author Shiwen (Sherlock) Li, PhD, a postdoctoral researcher in the Department of Population and Public Health Sciences at the Keck School of Medicine.
Several factors were associated with higher levels of PFAS in the blood. These include living in a neighborhood with low food access, living in a water district with PFAS contamination, and living within a three-mile radius of a PFAS-polluting facility or Superfund site. The results were just published in the journal Environmental Research.
Because participants in the study were primarily Latino, the findings provide evidence for the power of addressing neighborhood-level factors in reducing racial and ethnic environmental health disparities.
“We’re adding a different perspective to solving the PFAS problem, because the risk to exposure of PFAS at the neighborhood level is not evenly distributed,” Li said.
Mapping PFAS contamination
Li and his colleagues started with a simple question: What neighborhood factors predict differences in blood levels of PFAS? After obtaining blood samples and residential addresses from two predominantly Hispanic participant groups, the Metabolic and Asthma Incidence Research Study and the Study of Latino Adolescents at Risk, they conducted a series of analyses to dig deeper.
Using data on drinking water contamination from both the EPA and the state of California, the researchers found that people who lived in areas where perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) or perfluorohexanesulfonic acid (PFHxS) was found in drinking water had higher levels of those substance in their blood: a 1.54 nanogram per milliliter average increase for PFOS; 0.47 ng/mL for PFOA; and 1.16 ng/mL for PFHxS, compared to people living in areas without PFAS-contaminated water. The national averages for those PFAS range from about 1 to 6 ng/mL, so the increases are substantial, Li said.
Because PFAS are commonly found in food packaging, the researchers also explored whether low access to fresh food related to PFAS exposure. They used data from the U.S. Department of Agriculture, which defines low food access as a census tract where more than 500 people or one-third of the population live more than 0.5 miles from the nearest supermarket. They found that people living in neighborhoods with low food access had higher levels of PFOS, PFOA and perfluoroheptanesulfonic acid (PFHpS) in their blood (2.51 ng/mL, 0.6 ng/mL and 0.06 ng/mL, respectively), likely because they were more apt to consume packaged foods, Li said.
Finally, researchers studied whether living near a designated Superfund site or an industrial site known to process PFAS was linked to higher blood levels of PFAS. They found that for each industrial site processing PFAS within a three-mile radius, blood levels of PFOS increased. Living near a Superfund site predicted higher levels of PFOS, PFHxS, PFHpS and perfluoropentanesulfonic acid (PFPeS) in the blood.
Raising awareness on PFAS risks
New EPA rules are changing the way PFAS are regulated. Starting in 2024, these chemicals were included on the list of hazardous substances that can lead to a “Superfund site” designation, opening up additional funding for toxic waste cleanup. Another new rule, set to take effect in 2029, will regulate the levels of six PFAS in public drinking water.
“But in the meantime, those water systems are still contaminated with PFAS, and a lot of people don’t know they live in a neighborhood with water contamination. So, the first step is to raise awareness,” Li said. The Keck School’s Department of Population and Public Health Sciences has launched several community engagement efforts to share their research findings with people living in high-risk areas.
Next, Li and his team will explore PFAS exposure near chrome plating facilities, which use high levels of PFAS in their manufacturing processes.
About this research
In addition to Li, the study’s other authors are Jesse A. Goodrich, Elizabeth Costello, Carlos Cardenas-Iniguez, Jiawen Carmen Chen, Sarah Rock, Sandrah P. Eckel, Rob McConnell, Frank D. Gilliland, John Wilson and David V. Conti from the Department of Population and Public Health Sciences, Keck School of Medicine of USC, University of Southern California; Beau MacDonald from the Spatial Sciences Institute, Dornsife College of Letters, Arts and Sciences, University of Southern California; Adam L. Smith, Daniel L. McCurry, Amy E. Childress and Adam M.A. Simpson from the Sonny Astani Department of Civil and Environmental Engineering, Viterbi School of Engineering, University of Southern California; Douglas I. Walker and Damaskini Valvi from the Icahn School of Medicine at Mount Sinai, New York, New York; Tanya L. Alderete from Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; and Lucy Golden-Mason from the Department of Pediatrics, Children's Hospital Los Angeles, Saban Research Institute.
This work was supported by the USC President's Sustainability Initiative; the National Institute of Environmental Health Sciences [P30ES007048, R01ES030691, R01ES029944, R01ES030364, P01ES022845, and 5P01ES011627]; the National Institutes of Health [R01DK59211, and U01HG013288]; the Environmental Protection Agency [RD83544101]; and the Hastings Foundation. Funding for the PFAS measurements in both cohorts came from the National Institute of Environmental Health Sciences [R01ES029944].
Examining disparities in PFAS plasma concentrations: Impact of drinking water contamination, food access, proximity to industrial facilities and superfund sites
Article Publication Date
18-Nov-2024
COI Statement
Dr. Chatzi has served as an expert consultant for plaintiffs in litigation related to PFAS-contaminated drinking water.
Study: A Speed Limit on 3% of the Ocean Would Protect Whales
An international group of researchers has published a new study that maps areas of whale activity with areas of high shipping activity in order to find the places with the highest risk of whale strikes, a leading cause of whale mortality (alongside fishing). The upshot, according to the research team, is that it should be possible to reduce the number of strikes by regulating marine traffic on just 2.6 percent of the ocean's surface - though that 2.6 percent happens to be in areas that are very important to shipping.
“This is the first study to look at this problem at a global scale, enabling global patterns of collision risk to be identified using an extremely large contemporary dataset of four recovering whale species," said coauthor Dr. Jennifer Jackson of the British Antarctic Survey.
Shipping is a global phenomenon, and the merchant fleet is larger and more active now than at any point in history. The study found that marine traffic overlaps 92 percent of the habitat for blue, humpback, fin and sperm whales, the globe-spanning species covered by the study. Hotspots of ship strike risk were identified in every ocean region, except for the Southern Ocean, where there is little commercial interest for shipping. As might be expected, the risk tends to be concentrated on the coastal margins, where whales gather to seek feeding or breeding grounds and ships congregate to call at ports.
Clear high risk zones include the southwest coast of India; the southern tip of Africa; the southern coast of Brazil; the Strait of Gibraltar; and the coast of California, a well-studied whale strike corridor. Some of the areas analyzed have not been previously identified as risk zones for whale strikes, particularly areas off the coasts of developing nations in the global south.
The study found that "virtually no ship-strike risk hotspots were protected by mandatory measures" for speed reduction or routing. Adding mandatory measures for another 2.6 percent of the global ocean surface would cover all the hotspots; alternatively, protecting just 0.6 percent of the ocean's surface would cover multi-species hotspots (affecting two or more of the four whale species studied). The team noted that previous research on voluntary speed reduction programs have found evidence of only partial compliance, as some shipowners are willing to continue operation at full speed, despite encouragement to slow down.
"Changes in ocean ecosystems caused by the loss of historic whale populations have been hard to reverse. Ship-strike risk is a ubiquitous yet solvable conservation challenge for large whales, and our results can provide a foundation for expanded management measures to protect these ocean giants," the authors concluded.
The identified hot-spot areas may be comparatively small, but they include some of the busiest waterways in shipping, like the Strait of Gibraltar and the Cape of Good Hope route, where traffic has soared because of security issues in the Red Sea. The mandatory measures discussed could include a 10-knot speed limit, which could have a significant impact on transit times for container ship and car carrier operators on these routes.
Fewer than 7% of global hotspots for whale-ship collisions have protection measures in place
University of Washington
image:
A whale near a large vessel in southern Sri Lanka.
For public release at 2 p.m. U.S. Eastern Standard Time (11 a.m. Pacific Standard Time) on Thursday, Nov. 21, 2024
Fewer than 7% of global hotspots for whale-ship collisions have protection measures in place
According to the fossil record, cetaceans — whales, dolphins and their relatives — evolved from four-legged land mammals that returned to the oceans beginning some 50 million years ago. Today, their descendants are threatened by a different land-based mammal that has also returned to the sea: humans.
Thousands of whales are injured or killed each year after being struck by ships, particularly the large container vessels that ferry 80% of the world’s traded goods across the oceans. Collisions are the leading cause of death worldwide for large whale species. Yet global data on ship strikes of whales are hard to come by — impeding efforts to protect vulnerable whale species. A new study led by the University of Washington has for the first time quantified the risk for whale-ship collisions worldwide for four geographically widespread ocean giants that are threatened by shipping: blue, fin, humpback and sperm whales.
In the paper, published online Nov. 21 in Science, researchers report that global shipping traffic overlaps with about 92% of these whale species’ ranges.
“This translates to ships traveling thousands of times the distance to the moon and back within these species’ ranges each and every year, and this problem is only projected to increase as global trade grows in the coming decades,” said senior author Briana Abrahms, a UW assistant professor of biology and researcher with the Center for Ecosystem Sentinels.
“Whale-ship collisions have typically only been studied at a local or regional level — like off the east and west coasts of the continental U.S., and patterns of risk remain unknown for large areas,” said lead author Anna Nisi, a UW postdoctoral researcher in the Center for Ecosystem Sentinels. “Our study is an attempt to fill those knowledge gaps and understand the risk of ship strikes on a global level. It’s important to understand where these collisions are likely to occur because there are some really simple interventions that can substantially reduce collision risk.”
The team found that only about 7% of areas at highest risk for whale-ship collisions have any measures in place to protect whales from this threat. These measures include speed reductions, both mandatory and voluntary, for ships crossing waters that overlap with whale migration or feeding areas.
“As much as we found cause for concern, we also found some big silver linings,” said Abrahms. “For example, implementing management measures across only an additional 2.6% of the ocean’s surface would protect all of the highest-risk collision hotspots we identified.”
“Trade-offs between industrial and conservation outcomes are not usually this optimal,” said co-author Heather Welch, a research scientist with the National Oceanic and Atmospheric Administration and the University of California, Santa Cruz. “Oftentimes industrial activities must be greatly limited to achieve conservation goals, or vice versa. In this case, there is a potentially large conservation benefit to whales for not much cost to the shipping industry.”
Those highest-risk areas for the four while species included in the study lie largely along coastal areas in the Mediterranean, portions of the Americas, southern Africa and parts of Asia.
The international team behind the study, which includes researchers across five continents, looked at the waters where these four whale species live, feed and migrate by pooling data from disparate sources — including government surveys, sightings by members of the public, tagging studies and even whaling records. The team collected some 435,000 unique whale sightings. They then combined this novel database with information on the courses of 176,000 cargo vessels from 2017 to 2022 — tracked by each ship’s automatic identification system and processed using an algorithm from Global Fishing Watch — to identify where whales and ships are most likely to meet.
The study uncovered regions already known to be high-risk areas for ship strikes: North America’s Pacific coast, Panama, the Arabian Sea, Sri Lanka, the Canary Islands and the Mediterranean Sea. But it also identified understudied regions at high risk for whale-ship collisions, including southern Africa; South America along the coasts of Brazil, Chile, Peru and Ecuador; the Azores; and East Asia off the coasts of China, Japan and South Korea.
The team found that mandatory measures to reduce whale-ship collisions were very rare, overlapping just 0.54% of blue whale hotspots and 0.27% of humpback hotspots, and not overlapping any fin or sperm whale hotspots. Though many collision hotspots fell within marine protected areas, these preserves often lack speed limits for vessels, as they were largely established to curb fishing and industrial pollution.
For all four species the vast majority of hotpots for whale-ship strikes — more than 95% — hugged coastlines, falling within a nation’s exclusive economic zone. That means that each country could implement its own protection measures in coordination with the U.N.’s International Maritime Organization.
“From the standpoint of conservation, the fact that most high-risk areas lie within exclusive economic zones is actually encouraging,” said Nisi. “It means individual countries have the ability to protect the riskiest areas.”
Of the limited measures now in place, most are along the Pacific coast of North America and in the Mediterranean Sea. In addition to speed reduction, other options to reduce whale-ship strikes include changing vessel routings away from where whales are located, or creating alert systems to notify authorities and mariners when whales are nearby.
“Lowering vessel speed in hotspots also carries additional benefits, such as reducing underwater noise pollution, reducing greenhouse gas emissions, and cutting air pollution, which helps people living in coastal areas,” said Nisi.
The authors hope their global study could spur local or regional research to map out the hotspot zones in finer detail, inform advocacy efforts and consider the impact of climate change, which will change both whale and ship distributions as sea ice melts and ecosystems shift.
“Protecting whales from the impact of ship strikes is a huge global challenge. We’ve seen the benefits of slowing ships down at local scales through programs like ‘Blue Whales Blue Skies’ in California. Scaling up such programs will require a concerted effort by conservation organizations, governments and shipping companies,” said co-author Jono Wilson, director of ocean science at the California Chapter of The Nature Conservancy, which helped identify the need for this study and secured its funding. “Whales play a critical role in marine ecosystems. Through this study we have measurable insights into ship-collision hotspots and risk and where we need to focus to make the most impact.”
The research was funded by The Nature Conservancy, NOAA, the Benioff Ocean Science Laboratory, the National Marine Fisheries Service, Oceankind, Bloomberg Philanthropy, Heritage Expeditions, Ocean Park Hong Kong, National Geographic, NEID Global and the Schmidt Foundation.
Nisi AC et al. "Ship collision risk threatens whales across the world’s oceans." Science. Nov. 22, 2024 print edition. DOI: 10.1126/science.adp1950
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