Stark black against an open sky, common ravens are often spotted soaring above wolves in Yellowstone National Park. Researchers assumed that the notorious scavengers were following the wolves to get their scraps, but new research reveals a twist: Ravens don’t follow wolves, they remember common hunting grounds and regularly check back for fresh meat.

When food is easy to find, animals save energy by memorizing the path to retrieving it. Because scavengers rely on other animals to eat, their meals are less predictable. Some scavengers contend with this insecurity by tailing predators, but as this study shows, ravens don’t. Researchers tracked 69 ravens and 20 wolves across Yellowstone National Park for two and a half years and found that the ravens knew where to go without cues from the wolves.

“Scavengers are not quite as glorious as predators, and have traditionally been understudied by comparison. Getting a better understanding from the scavengers’ viewpoint might give us insight into sensory abilities, underappreciated environmental cues and spatial and temporal memory,” said , a ����Ӱ�Ӵ�ý professor emeritus of environmental and forest sciences and the study’s senior author.

March 12 in Science.

Ravens and wolves pick at the scraps of a wolf kill in Yellowstone National Park. Credit: Bob Landis

The mutualistic relationship between ravens and wolves has fascinated humans for centuries. According to Norse mythology, the god Odin created two ravens — — to travel the world gathering intelligence for him. Odin sent his two wolves, , with the ravens to ensure they remained fed.

“This tight coevolutionary relationship between predator and scavenger has persisted in human thought for millennia,” Marzluff said.

Modern scientific research documents a similar relationship between the two species. Ravens have been known to follow wolf tracks through the snow and respond to howls. After wolves were reintroduced to Yellowstone National Park in 1995, ravens were a wolf than anywhere else in the park. The odds of seeing a raven further increase when wolves are hunting.

Marzluff, who is well known for studying crows and ravens, teamed up with lead author , an assistant professor at the University of Veterinary Medicine Vienna then the Max Planck Institute of Animal Behavior, to study how ravens track wolves so well.

The wolves in Yellowstone are already closely monitored, but the researchers needed data on the ravens to compare. Over a few months, Marzluff and Loretto trapped 69 ravens and outfitted them with small GPS trackers. For two and a half years, the researchers monitored where the ravens and wolves went, which routes they took and when their paths crossed.

They only documented one instance of a raven following a wolf for an extended period, yet overall, ravens still managed to arrive promptly after the wolves made a kill. Ravens were spotted at nearly half the observed wolf kills within seven days and some flew more than 150 kilometers to reach a kill. Their flight patterns also suggested that the ravens were making a beeline instead of conducting a sweep.

Ravens were also far more likely to visit areas where wolf kills were more frequent, per the researchers’ “carcass abundance map,” which split the territory into nine square kilometer parcels and plotted kill sites.

The authors propose that ravens rely on spatial memory — the brain’s ability to follow directions — to monitor the wolves’ favorite hunting grounds. Their hypothesis is further supported by data showing that ravens fly over common kill sites en route to other food sources, including areas where humans hunt wild game.

“We already knew that ravens can remember stable food sources, like landfills,” Loretto said. “What surprised us is that they also seem to learn in which areas wolf kills are more common. A single kill is unpredictable, but over time some parts of the landscape are more productive than others — and ravens appear to use that pattern to their advantage.”

Additional co-authors include and from the Senckenberg Biodiversity and Climate Research Centre; , and Lauren Walker from National Park Service and and from ​​Max Planck Institute of Animal Behavior.

This study was funded by the European Union, the National Geographic Society, the German Research Foundation, the James W. Ridgeway endowment to the School of Environmental and Forest Sciences at the ����Ӱ�Ӵ�ý and Yellowstone Forever.

For more information, contact Marzluff at corvid@uw.edu or Loretto at�� matthias.loretto@vetmeduni.ac.at.

This story was adapted from by Max Planck Institute for Animal Behavior.

Four ����Ӱ�Ӵ�ý researchers have been named AAAS Fellows, according to a Jan. 31 by the American Association for the Advancement of Science. They are among 506 new fellows from around the world elected in 2022, who are recognized for their “scientifically and socially distinguished achievements” in science and engineering.

A tradition dating back to 1874, election as an AAAS Fellow is a lifetime honor, and all fellows are expected to meet the commonly held standards of professional ethics and scientific integrity. The new fellows will be celebrated in Washington, D.C., in summer 2023.

This year’s UW AAAS fellows are:

, professor in the Department of Linguistics, is honored for demonstrating the role of grammar in natural language processing (NLP), extending computational modeling to less-studied languages, and raising ethical issues in NLP – an interdisciplinary field concerned with the interactions between computers and human language. Bender studies the societal impacts of language technology, what it means for research and design of such technology, and how to include it in the NLP curriculum. She’s taught seminars on the topic and in 2021����for the North American Chapter of the Association for Computational Linguistics. Bender’s areas of focus include data documentation and the dangers of specific technology, such as large language models and chatbots used for search. She has worked to make linguistics accessible to computer scientists in NLP, giving tutorials at major conferences and writing two associated books. Bender also studies how computational methods can serve the purposes of linguistic analysis and how linguistic knowledge can be used to improve the performance of natural language processing systems. She has led the development of the , a framework supporting the creation of broad-coverage, precision, implemented grammars for diverse languages. Her other interests include sociolinguistic variation, or the ways speakers manipulate their languages to create style and register.

, a professor of wildlife science in the UW School of Environmental and Forest Sciences, is honored for advances in our understanding of how humans impact birds, and for communicating the importance of birds to the public. Marzluff’s lab studies the relationship between humans and birds to discover how to best conserve wildlife in our modern, human-dominated world. He focuses primarily on corvids — ravens, crows and jays — but he has also worked with falcons and hawks throughout North America and tundra-nesting birds in the Arctic. Marzluff also is interested in all the ways that birds affect people. He has written a number of books for researchers and lay audiences, including “Welcome to Subirdia” and “In Search of Meadowlarks.” Marzluff is a member of the board of editors for Ecological Applications, member of the U.S. Fish and Wildlife Service’s recovery team for the critically endangered Mariana crow, a fellow of the American Ornithologists’ Union and a National Geographic Society Explorer.

, professor of pharmacy and of health services, is honored for his work on medical and drug coverage and reimbursement policies, as well as for developing studies to address complex medical questions. Sullivan, who served as the dean of the UW School of Pharmacy from 2014 to 2022, was elected in 2020 to the National Academy of Medicine. He was one of the few people from the pharmacy field named to the academy, among the highest honors in health and medicine. Sullivan is widely recognized for pioneering U.S. guidelines for evidence-based preferred drug lists, also known as drug formularies. With insurers, he created the value-based formulary, which emphasizes a drug’s clinical effectiveness rather than its cost, and was the first health economist to serve on panels for global respiratory guidelines, incorporating economic considerations into recommendations. His research focuses on health technology assessment, medical decision-making, and the economic evaluation of medical technology, including pharmaceuticals. A member of the UW faculty since 1992, Sullivan holds adjunct appointments in the School of Medicine and in the Public Health Sciences Division at the Fred Hutch Cancer Center. Sullivan is currently on sabbatical at the London School of Economics and Political Science, and will return to UW this fall.

is being recognized for excellence in science and technical communication as a practitioner, instructor and mentor, particularly for her dedication to the communication of science to the public. Her research and teaching activities at the UW focused on science communication and media coverage of science and technology. She developed and taught courses for undergraduate and graduate students on writing about science for general audiences as well as on scientific and technical communication. Most recently, she received a Professional Development Fellowship from the National Science Foundation (NSF) to study mental models of audience and decision-making in science and technology communication. Previously, her research on accuracy in science news reporting received support from the NSF Ethics and Values Program in Science, Technology, and Society. Illman also directed the Chemistry Communication Leadership Institute, and in 2006, with funding from an , she focused on communicating about large and long-term multidisciplinary research efforts using the NSF Science and Technology Centers as a case study. Illman is a former Associate Editor of Chemical & Engineering News, the official news publication of the American Chemical Society, and she was founding editor of .

An astronomer tells tales of stargazing and pursuing the universe’s big questions, a grandparent shares wisdom for happy living, a jazz drummer lays down a cool new album …

But behold, yet more! An engineer pens STEM biographies for children, a cartoonist draws stories from his life, researchers ponder the future of river and wildlife conservation, and faculty masters bring out new classical recordings on guitar and piano.

Though 2020 was a holy humbug of a year, ����Ӱ�Ӵ�ý talents persevered, and published. Here’s a quick look at some giftworthy books and music created by UW faculty and staff, and a reminder of some recent favorites.

Stargazing stories: , associate professor of astronomy, published the anecdote-filled “” in August. “These are stories astronomers tell each other when all of us are hanging out at meetings,” Levesque said. Kirkus Reviews called them “entertaining, ardent tales from an era of stargazing that may not last much longer.”

‘Grand’ wisdom: , professor emeritus of English, has written novels, short stories and more, but takes a personal turn in “.” He offers his grandson, and readers, “what I hope are 10 fertile and essential ideas for the art of living.” It’s all presented “tentatively and with great humility,” Johnson says, as “grandfatherly advice is as plentiful as blackberries.”

Drums, duets: , assistant professor of music, released the album “” in March. Poor told UW News the music “is a celebration of space — space for drums to resonate and convey a feeling, and for the melody to dance around and push that feeling. It is primarily a collection of duets with saxophonist�� and the sound of the record is focused on drums and sax throughout.”

STEM stories: , professor of civil and environmental engineering, published two books for young readers this fall: “The Secret Lives of Scientists, Engineers, and Doctors,” volumes and . The volumes showcase “the struggle, growth and success” of 12 professionals in STEM fields, including a geneticist, a biologist, a cancer researcher and a scientist at the National Institutes of Health. More books are .

Life drawings: , professor of Slavic languages and literatures and comparative literature, published “,” a eclectic collection of drawings and essays, highlighting his different styles through the years, “from tragedy to tragicomedy to documentary to black humor,” he said.

Guitar works: School of Music faculty guitarist released his 10^th album in March. “” features classical guitar works written for him by composers and

Sheppard plays Brahms: , internationally known professor and pianist, put out a digital release of 107 early Brahms works in October, titled “.” The work joins Sheppard’s lengthy from a decades-long career.

Ecological restoration: How has climate change affected regional ecological restoration? , a research scientist in human centered design and engineering, looks for answers in “,” from UW Press.

River history: Seattle was born from the banks of the Duwamish River, writes BJ Cummings of the UW Superfund Research Program, but the river’s story, and that of its people, has not fully been told. Cummings seeks to remedy that with “,” published by UW Press.

Coexisting: Agriculture and wildlife can coexist, says , professor of environmental and forest sciences, in his book “.” But only “if farmers are justly rewarded for conservation, if future technological advancements increase food production and reduce food waste, and if consumers cut back on meat consumption.”

And here are some favorites from 2019:

O’Mara’s ‘Code’: History professor provides a sweeping history of California’s computer industry titans in “ The New York Times called it an “accessible yet sophisticated chronicle.”

Mindful travel: of the English Department and the Comparative History of Ideas program discusses how travelers can respectfully explore cultures with lower incomes, different cultural patterns and fewer luxuries in “.”

Kingdome man: , associate professor of architecture, studies the life and work of Jack Christiansen, designer of the Kingdome and other structures, in “,” published by UW Press.

Powerful silence: “,” a documentary directed by English professor about NFL star Marshawn Lynch’s use of silence as a form of protest, is available for rent or purchase on several platforms.

Seattle stories: UW Press republished English professor ‘s well-loved 1976 reflections on his city, “.” Sale, who taught at the UW for decades, died in 2017.

• Joanne De Pue, School of Music communications director, assisted with this story.

“” was published in February by Yale University Press.

“Agriculture and wildlife can coexist,” Marzluff, a professor of environmental and forest sciences, writes, “if farmers are justly rewarded for conservation; if future technological advancements increase food production and reduce food waste; and if consumers cut back on meat consumption.”��

Known also for his , Marzluff is the author of several books, including “” (2007) and “” (2015).

He argues that with human populations predicted to surpass 11 billion by the year 2100, agriculture stands at “crossroads” in its evolution. The new book reflects Marzluff’s study of sustainable food production farms and ranches across North and Central America, including vineyards in California, a Nebraska corn and soybean farm and small, sustainable farms in Costa Rica.

UW Notebook caught up with Marzluff with a few questions about the new book and his recommendations for sustainable food production that is not harmful to wildlife.

This work reflects a lot of field research, including actually camping in fields. What does it mean to “bird” a field — is it to count all visible birds? Or do you look for other evidence as well?

John Marzluff: Yes, in this case “bird” is a verb! When I bird a farm or ranch I’m mostly listening for birds.��It is a thrill when I can get my binoculars or scope on a bird, but hearing a bird sing or call is how most birdwatchers actually record the presence of a particular species. In addition to hearing or seeing a bird I might also record the presence of a nest, but that is a rare find.

You recommend that we waste less, eat less beef and other meat, and “close the yield gap.” What is the yield gap and how can it be reduced?

J.M.: Yield gaps are the difference in productivity between a field farmed as it is today and the same place farmed with technological advancements that increase productivity.��These gaps in what is and what could be harvested from a particular place on earth vary tremendously across the globe. In many parts of the Midwest of the United States or the breadbasket of Europe yield gaps are small, but in some regions of Africa where drought or low soil fertility limit harvest the gaps are large.

Even within a field of say 40 acres, yield gaps can vary as some pockets of soil dry quickly or have low nutrient content. Improving the drought resistance of seeds, planting cover crops and limiting tilling to enhance soil fertility, timing irrigation and the application of fertilizer to the needs of specific plants, fields, or regions, and developing crop varieties that are easier to harvest or more fecund are some of the ways farmers can close their yield gap.

You bring some hope by writing that we can all play a part in “meeting the grand challenge of feeding the world and saving nature.” What might a world look like that has successfully met these challenges?��

J.M.: First, agricultural landscapes would be much more diverse than most are today.��Rather than rows of crops running from horizon to horizon, we would see a mix of intensively farmed patches, reserves of native land, and many small and varied farms that intermix crops, livestock, fallow land, and natural features such as ponds, hedge rows, and “weedy” ditches.

The factories that today make pesticides and herbicides will in the future produce natural substitutes. As we shift our diet to one that includes less meat generally, and less grain-fed beef, specifically, we will no longer see feedlots but rather cattle and bison grazing in harmony with prairie wildlife, such as meadowlarks, bobolinks, prairie dogs, and badgers.�� By effective lobbying of our policymakers we would see incentives for farmers to grow human food and conserve habitat and the elimination of subsidies for those who grow cattle feed and fuel stocks. As a result, the corn fields of the future will grow varieties we can eat and many grassland and shrubland endangered species would start to recover.

But this is only half of the equation, we must also see a revitalization of farming communities, which will happen more quickly when we purchase foods and goods that provide farmers a decent wage and empower the young and the women who choose to return to the land with the ability to own the land that they work.

While I am hopeful, I am not patient, so we need to do our part to meet this challenge now.

• Read John Marzluff’s story map article about his book “In Search of Meadowlarks” and sustainable food production.

Here in what is called the era, humans and our urban environments appear to be driving accelerated evolutionary change in plants, animals, fungi, viruses and more — changes that could affect key ecosystem functions and thus human well-being. These interactions between evolution and ecology are called “eco-evolutionary feedback.”

The National Science Foundation has awarded a five-year, $500,000 to a multi-institution research network team headed by , ����Ӱ�Ӵ�ý professor of urban design and planning, to advance understanding of these global eco-evolutionary dynamics.

Alberti is the author or co-author of several papers on the emerging topic, as well as a 2016 book, “Cities that Think Like Planets: Complexity, Resilience, and Innovation in Hybrid Ecosystems” (UW Press).

“Cities are microcosms of the evolutionary changes that are occurring on a planetary scale,” Alberti writes in the grant statement, “and thus provide a natural laboratory to advance our understanding of eco-evolutionary dynamics in a rapidly urbanizing world and��generate new insights for maintaining biodiversity.”

Human-caused evolutionary changes in plants, animals, fungi, viruses and other organisms can affect nutrient cycling, pollination, seed dispersal, water and air purification and food production. The challenge, Alberti writes, is to understand these mechanisms, “and determine whether these changes might affect ecosystem function at the planetary scale.”

Such a challenge can’t be fully met by any single field, she adds, and calls for a new level of collaboration — and sharing of data and methods —among evolutionary biologists, ecosystem scientists, urban ecologists, paleoecologists and archaeologists.

Alberti, who also directs the UW Urban Ecology Research Lab in the UW College of Built Environments, intends to lead the researchers to “perform long-term cross-comparative studies, to synthesize the science, and to explore mechanisms that link urban development patterns to rapid evolution and the potential for those changes to feed back to shape ecosystems.”

Key questions the research network will address are:

• What is the evidence for urban signatures of phenotypic change — the physical manifestation of genes — distinct from natural and other anthropogenic, or human-caused drivers?
• To what degree does urban trait change differ among branches of the tree of life?
• To what degree can trait changes be attributed to phenotypic plasticity or to evolutionary change?
• What are the functional consequences of urban-induced evolutionary changes on ecosystems?

Alberti is principal investigator for the new Research Coordination Network under the title “Eco-Evolutionary Dynamics in an Urban Planet: Underlying Mechanisms and Ecosystem Feedbacks.”

Co-principal investigators are of McGill University in Montreal, of the University of Toronto at Mississauga, of Washington University in St. Louis and , of Fordham University. The UW’s , a professor of environmental and forest sciences, is also part of the network.

Other researchers with the network are from Universidad Austral de Chile; Arizona State University; the University of Leuven, Belgium; the University of California, Santa Cruz; the Cary Institute of Ecosystem Studies; the University of New Mexico; the University of Warsaw and Virginia Commonwealth University.

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For more information, contact Alberti at malberti@uw.edu. Follow her on Twitter: @ma003.

NSF grant # 1840663

For over a century, speciation — where one species splits into two — has been a central focus of evolutionary research. But a new study almost 20 years in the making suggests “speciation reversal” — where two distinct lineages hybridize and eventually merge into one — can also be extremely important. The , appearing March 2 in Nature Communications, provides some of the strongest evidence yet of the phenomenon, in two lineages of common ravens.

“The bottom line is [speciation reversal] is a natural evolutionary process, and it’s probably happened in hundreds or almost certainly thousands of lineages all over the planet,” said , professor of biological sciences at University of Maryland, Baltimore County (UMBC) and co-author on the new study. “One of our biggest goals is to just have people aware of this process, so when they see interesting patterns in their data, they won’t say, ‘That must be a mistake,’ or, ‘That’s too complicated to be correct.’”

“We examined genomic data from hundreds of ravens collected across North America,” said , the study’s first author and a former postdoctoral fellow at UMBC, who is now a postdoc at the Smithsonian Center for Conservation Genomics. “Integrating all of the results across so many individuals, and from such diverse datasets, has been one of the most challenging aspects of this study. Next-generation genomic techniques are revealing more and more examples of species with hybrid genomes.”

When Omland initially began work on this project in 1999, common ravens were considered a single species worldwide. He thought further research might uncover two distinct species — perhaps an “Old World” and “New World” raven — but the real story is much more complicated. Omland reported the existence of two common raven lineages in 2000, one concentrated in the southwestern United States dubbed “California,” and another found everywhere else (including Maine, Alaska, Norway and Russia) called “Holarctic.”

Since then, the plot has thickened. Two undergraduates in Omland’s lab, Jin Kim and Hayley Richardson, analyzed mitochondrial DNA from throughout the western United States and found the two lineages are extensively intermixed. In 2012, the Norwegian Research Council provided major funding for the project and Kearns spent a year at the University of Oslo analyzing nuclear genome data.

The best explanation based on the team’s analysis is that the California and Holarctic lineages diverged for between one and two million years, but now have come back together and have been hybridizing for at least tens of thousands of years.

“It is fascinating to me that this complex history of raven speciation has been revealed. For decades my students and I held and studied ravens throughout the West and never once suspected they carried evidence of a complex past,” said co-author , professor of wildlife science at the ����Ӱ�Ӵ�ý. “Thanks to collaborations among field workers and geneticists, we now understand that the raven is anything but common.”

How does this relate to people? Humans are also a product of speciation reversal, Omland notes, with the present-day human genome including significant chunks of genetic material from Neanderthals and Denisovans, another less well-known hominid lineage. Recent genetic studies have even indicated a mysterious fourth group of early humans who also left some DNA in our genomes.

“Because speciation reversal is a big part of our own history,” Omland said, “getting a better understanding of how that happens should give us a better sense of who we are and where we came from. These are existential questions, but they are also medically relevant as well.”

Next steps in the current avian research include analyzing genetic data from ravens who lived in the early 1900s to investigate the potential role of humans in the speciation reversal process. “Getting genomic data out of such old, degraded specimens is challenging,” Kearns said, “and all work must be done in a special ‘ancient DNA’ lab at the Smithsonian’s Center for Conservation Genomics.”

If those ravens have a similar distribution of genes from the Holarctic and California lineages as the ravens living today, it’s unlikely changes in human civilization over the last century played a role.

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For more information, contact Kearns at kearnsa@si.edu; Johnsen at arild.johnsen@nhm.uio.no; Omland at omland@umbc.edu or 410-455-2243; and Marzluff at corvid@uw.edu or 206-616-6883.

Suburban development is forcing some songbirds to divorce, pack up and leave and miss their best chances for successful reproduction.

As forested areas increasingly are converted to suburbs, birds that live on the edge of our urban footprint must find new places to build their nests, breed and raise fledglings. published Dec. 28 in the journal finds that for one group of songbirds — called “avoiders” — urban sprawl is kicking them out of their territory, forcing divorce and stunting their ability to find new mates and reproduce successfully, even after relocating.

“The hidden cost of suburban development for these birds is that we force them to do things that natural selection wouldn’t have them do otherwise,” said lead author , a professor of wildlife science in the ����Ӱ�Ӵ�ý’s .

“Because development requires that these birds move, we force them to abandon the places they selected and go elsewhere, which often entails finding new mates when they wouldn’t have otherwise.”

Avoider birds are species that are known to decline in response to urbanization, for example when forested areas are removed for developments. In the Pacific Northwest, two avoiders are the and — birds that are generally shy of humans and rely on groundcover and brush such as fallen trees, root balls, shrubs and ferns for breeding.

The manicured yards of many suburban neighborhoods often do away with native habitat, and these species must flee to be able to nest and mate. When they leave, the birds travel uncharacteristically far for breeding adults — about one and a half football fields, on average.

The researchers suspect this forced dispersal is the most damaging aspect of suburban development on birds and the reason why some species decline when forests are replaced with subdivisions. When forced to move, the avoider birds largely failed to reproduce again for at least one year after relocating. The whole transition to a new home and often a new partner might cause a bird to lose half of its breeding years.

“These birds don’t like to move once they have established a territory,” Marzluff said. “But when it comes to having enough food and safety for a nest, and being able to attract a mate, that’s when things get tough. That’s probably when they decide to move.”

In general, monogamous birds will “divorce” their mate and move to a new territory if they have a reason to. Maybe they miss a season to reproduce because of a poor partner, and moving is beneficial because ultimately it increases their reproductive success. But for sensitive species, the opposite is true when movement is forced.

The researchers also studied another category of bird, called “adapters” or “exploiters,” which includes species that tolerate or even thrive around human development. These are the , , and . Sparrows and towhees will live in tandem with humans, often finding suitable breeding grounds in backyards, while Bewick’s wrens will gladly nest in a bird box and juncos even see opportunity in a door-hung Christmas wreath.

The adapter birds also moved around, but mainly of their own accord to improve their chances of breeding successfully, not in response to changing landscapes. As a result, suburban development didn’t appear to impact their ability to reproduce.

The researchers identified and monitored hundreds of individually marked songbirds from six common species found in Seattle-area suburbs. For about 10 years, Marzluff and a number of graduate students tracked bird activity in three types of landscapes: forested preserves, already developed suburban neighborhoods and neighborhoods transitioning from forest to subdivision. By placing bands around the birds’ legs and mapping sightings of mated pairs and nest locations, the researchers were able to tell when a bird relocated, broke up from its mate or stayed put year to year.

This study’s long tenure and focus on multiple species is a first for the field and allowed researchers to compare birds’ behavior across species. It is also one of the only studies to look at how and why birds disperse in the urban ecosystem — and what effect that can have on mating and breeding.

The researchers expect a similar pattern in other cities and suburbs across the U.S., though the species involved will vary depending on region. In other parts of the world where species diversity is much higher — in the tropics, for instance — the effects of urbanization on birds dispersing and some ultimately failing to reproduce could be much greater, Marzluff said. Instead of just one or two territories lost to deforestation, entire colonies that are specific to a small area might be lost.

“To conserve some of these rarer species in an increasingly urban planet is going to require more knowledge of how birds disperse,” Marzluff said. “I expect that as we look more closely, we will find birds that are compromised because of us.”

Other co-authors are , a UW assistant professor of environmental and forest sciences; and Jack DeLap, David Oleyar and Kara Whittaker, all former UW doctoral students.

This study was funded by the National Science Foundation and the UW.

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For more information, contact Marzluff at corvid@uw.edu or 206-616-6883.

More images:��

A new multi-institution study led by the ����Ӱ�Ӵ�ý that examines 1,600 global instances of phenotypic change — alterations to species’ observable traits such as size, development or behavior — shows more clearly than ever that urbanization is affecting the genetic makeup of species that are crucial to ecosystem health and success.

Their was published Jan. 2 in the . Lead author is , professor of urban design and planning and director of the in the UW .

“We found a clear urban signal of phenotypic change — and greater phenotypic change in urbanizing systems compared to natural and non-urban anthropogenic, or human-created systems,” Alberti said.

She said the findings open new opportunities for advancing our understanding of the role of humans in Earth’s evolution: “By explicitly linking urban development to heritable traits that affect ecosystem function, we can begin to map the implications of human-induced trait changes for ecological and human well-being.”

Rapid urbanization, the researchers write, poses new challenges for species, some of which will adapt or relocate while others go extinct. With this study, they sought to learn whether signs of human-caused change could be detected across species in urban ecosystems worldwide, and to what extent humans and our cities and societies might be speeding up these changes.

They analyzed 1,600 observations of phenotypic change across multiple regions and ecosystems worldwide, in a geo-referenced database, looking to discriminate between such human-caused signals and natural baselines and “non-urban drivers.”

They also assessed the relative impact of several human-caused “urban disturbances,” including the acidification and pollution of lake habitats, the relocation of animals, heat and effluent associated with a power plant, long-term harvesting of certain medicinal plants — even the apparent effects of global warming on the reproductive patterns of birds.

They propose that “urban-driven contemporary evolution” will affect sustainability from the level of the urban ecosystem to the planetary scale.

“The significance of these changes is that they affect the functioning of ecosystems,” Alberti said. “They may inhibit the ability of seeds to disperse, cause exposure to infectious diseases, or even change the migratory patterns of some species.”

Some examples of this include:

• human-caused global warming is prompting the seasonal onset of reproduction to occur earlier in 65 species of migratory birds in Western Europe
• the use of galvanized (zinc-coated) transmission towers creates “novel habitats” characterized by high zinc tolerance in multiple plant species
• the size of brown trout is being affected by fish ladders, which subsequently affects predators and prey

Alberti’s UW co-authors are , professor of environmental and forest sciences, and Victoria Hunt of the Department of Urban Design and Planning.��

Marzluff said, “Our findings of rapid and substantial adjustment by many plants and animals to the challenges of living in an increasingly urban world demonstrate the power of natural selection where we live, work, worship and play.”

But he added that the research also offers hope to those interested in conserving biological diversity: “Certainly many species have been, and will continue to be, extinguished by human action, but we reveal how others are evolving the necessary strategies and physical characteristics to coexist with humanity.”

The research, Alberti concluded, calls for a new collaboration among evolutionary biologists, conservation biologists and urban scientists to better understand how humans may affect evolutionary processes and to inform conservation strategies to steer such changes toward a desirable future.

Other co-authors are Cristian Correa of the Universidad Austral de Chile; Andrew Hendry of McGill University; Eric Palkovacs and Travis Apgar of the University of California, Santa Cruz; Kiyoko Gotanda of the University of Cambridge; and Yuyu Zhou of Iowa State University.

The research was funded by the MacArthur Foundation as well as the National Commission for Scientific and Technological Research and National Fund for Scientific and Technological Development, in Chile.

Members of this research team on the theme of human influences on evolution. The summary to that series recalls Charles Darwin’s century-old comment on evolution that “we see nothing of these slow changes in progress, until the hand of time has marked the long lapse of ages.”

The authors of the series added: “Now, however, we have a completely different view. Rapid evolution is occurring all around us all the time. Many of the most extreme examples of rapid evolution are associated with human influences, leading to the oft-repeated assertion that humans are ‘the world’s greatest evolutionary force.'”

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For more information, contact Alberti at 206-616-8667 or malberti@uw.edu, or Marzluff at 206-616-6883 or corvid@uw.edu.

Grant numbers: 14-106477-000-USP (MacArthur Foundation), CONICYT-PAI 82130009 (National Commission for Scientific and Technological Research) and FONDECYT 11150990 (National Fund for Scientific and Technological Development)

If you live in Seattle or Berlin, the answer is yes, to the tune of $120 million and $70 million a year for each city, respectively.

A published last month in the journal tries to determine what economic value residents in two comparable cities place on having birds in their backyards and parks. Researchers at the ����Ӱ�Ӵ�ý and Humboldt State University compared two types of common birds – finches and corvids – in both cities, asking residents how much they would pay to conserve the species and what they spend, if anything, on bird food.

They found that both cities place a “sizeable” value on bird enjoyment, somewhat more so in Seattle. Residents in both cities spend more than the average U.S. adult on bird-supporting activities, suggesting that people from Seattle and Berlin value having birds around their homes and neighborhoods more than in most cities.

These activities, in turn, also show that birds benefit the local economies as residents invest in food and nesting structures.

“This paper shows that our interactions with birds actually have a pretty high economic return to the community where you live,” said , a UW professor of environmental and forest sciences and the paper’s co-author. “We know that having a livable, green community that attracts birds also increases the value of homes in that area. This paper shows there’s an economic service birds are providing.”

Researchers say this is the first look at estimating the economic value of enjoying common birds in an urban setting. Previous studies have assessed people’s willingness to pay to see rare or charismatic birds and to pay for conservation of endangered species, but these instances don’t affect most people.

“No one has really looked at what people will be willing to pay for these more common species, ones that aren’t necessarily endangered or threatened. We wanted to address that because people living in urban areas don’t encounter endangered species on a daily basis,” said co-author , a lecturer at Humboldt State University who completed this study as a postdoctoral researcher at the UW.

Clucas in the Seattle area and collaborators in Berlin went door-to-door and surveyed dozens of households in different types of neighborhoods – urban with apartments, dense suburban, light suburban and rural. The researchers asked specific questions about how residents viewed corvid and songbird species, whether they would pay for conservation of these species and what they spent annually on bird food.

In both Seattle and Berlin, residents’ willingness to pay for bird conservation was higher for finch species than for corvids. Interestingly, some Seattleites said they would pay to actually reduce the crow population in the city, though many also appeared indifferent about crows.

In contrast, Berliners were willing to pay a small amount to increase the city’s crow population, but they had an overall negative reaction to conserving magpies, another corvid species associated by legend with stealing and mischief.

“There’s a lot of culture that goes along with these birds, and that influences how we view them,” Marzluff said.

The researchers also noted that residents living in the urban core in both cities interacted the least with birds. The more that we as humans feed and house birds, the more variety and density appear around our homes. If that interaction isn’t happening in urban cores, “there’s a greater disconnect between nature and humans in those areas, and that’s where most of the population lives,” Marzluff said.

That interaction is important for human-nature connections that can lead to greater appreciation for the natural world, he added.

of the UW is a co-author on the paper. The study was funded by the U.S. Department of Agriculture and the German Research Foundation.

https://youtu.be/m7pOlAGRHnI

For more information, contact Marzluff at corvid@uw.edu or 206-616-6883 and Clucas at barbara.clucas@humboldt.edu or 707-826-5156.

Q: Please explain the suburban birds you describe as “adapters” and “exploiters.”
A: Adapters are birds that take advantage of the new foods and nesting opportunities that exist in suburban settings. They include familiar birds like chickadees, goldfinches, Canada geese and red-tailed hawks. The abundance of adapters increases with development because they utilize edges that exist between the many distinct built and natural landscapes in our neighborhoods.

Exploiters are even more in tune with humanity than are the adapters. They often have “house” or “barn” in their name, such as barn swallow, barn owl and house finch. My favorite, the American crow, and the denizen of Costco parking lots, the Brewer’s blackbird, are exploiters. Exploiters may attain dense populations, but some are declining as the last scruffy parts of today’s cities are tidied up and the cracks and crevices in older homes are sealed. The house sparrow and jackdaw of Europe are two exploiters on the decline.

In many cases, adapters and exploiters can show us how natural selection fashions the birds that live among us. Blackcap warblers in Europe, for instance, are in the throes of speciation as some in the population are evolving new migratory routes and morphologies that enable them to exploit bird feeders in England.

Evolution of birds in our backyards tells me that humans, while often destructive, also have a creative hand in shaping biological diversity.

Q: What about the “avoiders”?

A: In contrast, avoiders decline in the face of human action. To these species, our activities are as deadly as the meteors of the past. Avoiders require extensive natural habitat situated far from cities. A familiar local avoider is the northern spotted owl, but even the small Pacific wren is an avoider. Many birds that annually migrate from the neotropics to breed in and around Seattle, such as western tanagers, black-throated grey warbler, and Wilson’s warblers, are avoiders.

In the Northwest, there are many fewer avoiders than adapters, so bird diversity is highest in suburban settings and declines as we move either closer to the city or farther from it. This pattern is common across the northern Europe, Asia and Australia.

However, avoiders dominate tropical forest communities, so in those hyper-diverse settings development is likely to steadily decrease diversity.

Understanding that local diversity is a careful balance of animals that seek and avoid people teaches us that urbanization is not the answer to our conservation prayers. Rather, learning to appreciate the animals that co-exist where we live, work and play can motivate us to make the sacrifices – setting aside distant lands – that avoiders require.

Q: You’re tweeting on about wildlife in your suburban backyard in Snohomish County. What’s the most fun thing this fall?
A: What’s not to enjoy about a mature bald eagle or rough-skinned newt in the yard? But I’ve certainly had the most fun with the newest addition to my yard – a male mountain beaver that was unwanted in his former abode and now has been successfully transplanted to my sword fern-encrusted hillside. I’ll be following his progress throughout the winter.

How do you know Jack DeLap, the artist who illustrated the book?
A: is not only a talented artist, but also a scientist in my lab. Jack started at the UW the year I was hired. As part of an expansion of his fine arts degree, Jack was working on a second bachelor’s degree in wildlife science. Since then he completed a master’s at Colorado State University and then returned here to do doctoral work on the urban bird community that he elegantly illustrated for Subirdia.

Q: What are examples from your “Nature’s 10 commandments”– the things animals would ask for if they could get our attention?
A: All animals would appreciate it if we lessened our fascination for large, manicured, turf lawns. Reducing lawn size and replacing lawns with native (or even nonnative) shrubs would increase the ability of suburbs to support ground-nesting birds, small mammals, salamanders and garter snakes.

Our birds would ask that we do two simple things: keep our cats inside – outdoor cats kill up to 3.7 billion birds per year in the U.S. alone – and make our large-paned glass windows more visible. This can be accomplished by adding UV-reflective stickers to windows.

The UW could make a great contribution to bird safety by making our windows visible and by turning off Husky Stadium lights when the field is not in use. Birds and other animals living by the lake are negatively affected by excessive night lighting.

By stocking bird feeders and providing bird houses we can help build large populations of adapters and exploiters, which is a key feature in their ability to continually adapt and evolve in response to the challenges we present to them.

Finally, we live and work in such a wonderful and natural place that I hope we can all take a bit of time each day to celebrate the nature around us. Share that passion for life with colleagues, students and family members so that they, too, develop an ethic that, as Aldo Leopold wrote 60 years ago, values our land as a community, not simply a commodity.