It’s hard to imagine life on Earth without mammals.They swim in the depths of the ocean,hop across deserts in Australia and travel to the moon.This diversity can be deceiving,at least when it comes to how mammals create the next generation.Based on how they reproduce,nearly all mammals alive today fall into one of two categories:placental mammals and marsupials.Placentals,including humans,whales and rodents,have long gestation periods.They give birth to well-developed young—with all major organs and structures in place—and have relatively short weaning periods,or lactation periods,during which young are nursed on milk from their mothers.Marsupials,like kangaroos and opossums,are the opposite:They have short gestation periods—giving birth to young that are little more than fetuses—and long lactation periods during which offspring spend weeks or months nursing and growing within the mother’s pouch,or marsupium.For decades,biologists saw the marsupial way of reproduction as the more“primitive”state,and assumed that placentals had evolved their more“advanced”method after these two groups diverged from one another.But new research is testing that view.In apaper published July 18 in The American Naturalist,a team led by researchers at the University of Washington and its Burke Museum of Natural History and Culture present evidence that another group of mammals—the extinct multituberculates—likely reproduced in aplacental-like manner.Since multituberculates split off from the rest of the mammalian lineage before placentals and marsupials evolved,these findings question the view that marsupials were“less advanced”than their placental cousins.“This study challenges the prevalent idea that the placental reproductive strategy is‘advanced’relative to amore‘primitive’marsupial strategy,”said lead author Lucas Weaver,a postdoctoral researcher at the University of Michigan who conducted this study as aUW doctoral student.“Our findings suggest that placental-like reproduction either is the ancestral reproductive route for all mammals that give birth to live young,or that placental-like reproduction evolved independently in both multituberculates and placentals.”Multituberculates arose about 170 million years ago in the Jurassic.Most were small-bodied creatures,resembling rodents.For much of their history,multituberculates were the most abundant and diverse group of mammals.But scientists know very little about their life history,including how they reproduced,because of their generally poor fossil record.The last multituberculates died out about 35 million years ago.Weaver reasoned that the microscopic structure of fossilized bone tissues can house useful life-history information about multituberculates,such as their growth rate.Working under co-author Gregory Wilson Mantilla,a UW professor of biology and curator of vertebrate paleontology at the Burke Museum,Weaver and his colleagues obtained cross sections of 18 fossilized femurs—the thigh bone—from multituberculates that lived approximately 66 million years ago in Montana.All 18 samples showed the same structural organization:a layer of disorganized bone“sandwiched”between an inner and outer layer of organized bone.Disorganized bone,or woven bone,indicates rapid growth and is so named because,under amicroscope,the layers of bone tissue are laid out in acrisscrossed fashion.In organized bone,which reflects slower growth,layers are parallel to one another.The researchers then examined femoral cross sections taken from 35 small-bodied mammalian species that are living today—28 placentals and seven marsupials,all from Burke Museum collections.Nearly all of the placental femurs showed the same“sandwich”organization as the multituberculates.But all of the marsupial femurs consisted almost entirely of organized bone,with only asliver of disorganized bone.The team believes that is stark difference likely reflects their divergent life histories.“The amount of organized bone in the outermost layer,or cortex,of the femur strongly correlates with the length of the lactation period,”said Weaver.“Marsupials have long lactation periods and alot of organized bone in the outermost cortex.The opposite is true for placentals:a short lactation period and much less organized bone in the outermost cortex.” 查看详细>>

Wireless sensors can monitor how temperature,humidity or other environmental conditions vary across large swaths of land,such as farms or forests.These tools could provide unique insights for avariety of applications,including digital agriculture and monitoring climate change.One problem,however,is that it is currently time-consuming and expensive to physically place hundreds of sensors across alarge area.Inspired by how dandelions use the wind to distribute their seeds,a University of Washington team has developed atiny sensor-carrying device that can be blown by the wind as it tumbles toward the ground.This system is about 30 times as heavy as a1 milligram dandelion seed but can still travel up to 100 meters in amoderate breeze,about the length of afootball field,from where it was released by adrone.Once on the ground,the device,which can hold at least four sensors,uses solar panels to power its onboard electronics and can share sensor data up to 60 meters away.The team published these results March 16 in Nature.“We show that you can use off-the-shelf components to create tiny things.Our prototype suggests that you could use adrone to release thousands of these devices in asingle drop.They’ll all be carried by the wind alittle differently,and basically you can create a1,000-device network with this one drop,”said senior author Shyam Gollakota,a UW professor in the Paul G.Allen School of Computer Science&Engineering.“This is amazing and transformational for the field of deploying sensors,because right now it could take months to manually deploy this many sensors.” 查看详细>>

Accidentally trapping sharks,seabirds,marine mammals,sea turtles and other animals in fishing gear is one of the biggest barriers to making fisheries more sustainable around the world.Marine protected areas—sections of the ocean set aside to conserve biodiversity—are used,in part,to reduce the unintentional catch of such animals,among other conservation goals.Many nations are calling for protection of 30%of the world’s oceans by 2030 from some or all types of exploitation,including fishing.Building off this proposal,a new analysis led by the University of Washington looks at how effective fishing closures are at reducing accidental catch.Researchers found that permanent marine protected areas are arelatively inefficient way to protect marine biodiversity that is accidentally caught in fisheries.Dynamic ocean management—changing the pattern of closures as accidental catch hotspots shift—is much more effective.The results were published Jan.17 in the Proceedings of the National Academy of Sciences.A full list of co-author names and institutions is listed in the paper.No outside funding was used in this research.For more information,contact Hilborn at rayh uw.edu and Pons at mpons uw.edu. 查看详细>>

Many animals have tusks,from elephants to walruses to hyraxes.But one thing today’s tusked animals have in common is that they’re all mammals—no known fish,reptiles or birds have them.But that was not always the case.In astudy published Oct.27 in the Proceedings of the Royal Society B,a team of paleontologists at Harvard University,the Field Museum,the University of Washington and Idaho State University traced the first tusks back to ancient mammal relatives that lived before the dinosaurs.“Tusks are this very famous anatomy,but until Istarted working on this study,I never really thought about how tusks are restricted to mammals,”said lead author Megan Whitney,a postdoctoral researcher at Harvard University and aUW doctoral alum.“We were able to show that the first tusks belonged to animals that came before modern mammals,called dicynodonts,”said co-author Ken Angielczyk,a curator at the Field Museum in Chicago.“Despite being extremely weird animals,there are some things about dicynodonts—like the evolution of tusks—that inform us about the mammals around us today.”Dicynodonts lived from about 270 to 201 million years ago,largely before the so-called“time of the dinosaurs.”They ranged from rat-to elephant-sized.Modern mammals are their closest living relatives,but they looked more reptilian,with turtle-like beaks.One of their defining features is apair of protruding tusks in their upper jaws.The word dicynodont means“two canine teeth.”Not all protruding teeth are tusks.Their composition and growth patterns reveal whether they count.“For this paper,we had to define atusk,because it’s asurprisingly ambiguous term,”said Whitney.For atooth to be atusk,the researchers argued it must extend out past the mouth,keep growing throughout the animal’s life and,unlike most mammals’teeth—including ours—tusks’surfaces are made of dentine rather than hard enamel.Under these parameters,elephants,walruses,warthogs and hyraxes have tusks.Other big teeth in the animal kingdom don’t make the cut,though.For instance,rodent teeth,even though they sometimes stick out and are ever-growing,have an enamel band on the front of the tooth,so they don’t count.Some of the dicynodont tusks that the team observed in Zambia didn’t fit the definition of atusk either:They were coated in enamel instead of dentine.The different makeup of teeth versus tusks gives scientists insights into an animal’s life.“Enamel-coated teeth are adifferent evolutionary strategy than dentine-coated tusks,”said Whitney.“It’s atrade-off.”Enamel teeth are tougher than dentine.But because of the geometry of how teeth grow in the jaw,if you want teeth that keep growing throughout your life,you can’t have acomplete enamel covering.Animals like humans made an evolutionary investment in durable but hard-to-fix teeth—once our adult teeth grow in,we’re out of luck if they get broken.Tusks are less durable,but they grow continuously,even if they get damaged.It’s like the compromise of getting acar that’s very reliable but very difficult to get repaired,versus driving abeater that needs frequent repairs but is cheap and easy to fix. 查看详细>>

Science is in the midst of adata deluge:Experiments are churning out more information than researchers can process.But anew endeavor,centered on artificial intelligence,will help scientists navigate this data-rich reality.On Sept.28,the National Science Foundation announced a$15 million,five-year grant to integrate AI tools into the scientific research and discovery process.The award will fund the Accelerated AI Algorithms for Data-Driven Discovery Institute—or A3D3 Institute—a partnership of nine universities,led by the University of Washington.The A3D3 Institute aims to accelerate the discovery pipeline by providing scientists with new,paradigm-shifting AI tools for analyzing the types of large and complex datasets that are an increasingly common feature of research—from medical laboratories to particle colliders.“I have been fortunate to work with an exceptional group of talented researchers,and am thrilled to continue to be apart of solving some of the most fundamental issues in science and engineering.The ultimate goal of A3D3 is to construct the institutional knowledge essential for real-time applications of AI in any scientific field,”said Shih-Chieh Hsu,a UW associate professor of physics and director of the A3D3 Institute.“A3D3 will empower scientists with new tools to deal with the coming data deluge through dedicated outreach efforts.”The A3D3 Institute—part of the NSF’s Harnessing the Data Revolution program—is acollaboration among researchers at the University of Washington;the University of Illinois at Urbana-Champaign;Duke University;the Massachusetts Institute of Technology;the University of Minnesota,Twin Cities;the California Institute of Technology;Purdue University;the University of California,San Diego;and the University of Wisconsin–Madison.In addition to Hsu,other UW faculty involved with the A3D3 Institute are Scott Hauck,professor of electrical and computer engineering;Amy Orsborn,assistant professor of bioengineering and of electrical and computer engineering;and Eli Shlizerman,associate professor of applied mathematics and of electrical and computer engineering.From detectors searching for gravitational waves to electrical sensors monitoring the activity of the brain,research is handing scientists ever-larger datasets to analyze.Experiments are generating more data in part because researchers are developing better tools,from sharper medical imaging techniques to more precise sensors for particle physics experiments.A single experiment at CERN’s Large Hadron Collider,for example,can generate 1petabyte of data—that’s 1million gigabytes—per second from tens of millions of collisions.But as datasets increase in size and complexity,the algorithms needed to analyze data and put the most relevant bits—or bytes—before the eyes of scientists run the risk of outstripping current computing capacity. 查看详细>>

It was wartime and food was scarce.Leaders of England’s effort to wage war and help the public survive during World War II needed to know:Were the rations in lifeboats adequate for survival at sea?And,among several experiments important for public as well as military heath,how much vitamin Cdid aperson need to avoid the deadly disease scurvy?In one experiment at the Sorby Research Institute in Sheffield,called the“shipwreck”experiment,volunteers were fed only what the navy carried in lifeboats.The grueling experiment resulted in more water and less food being carried in lifeboats.One of the more robust experiments run on human subjects during this time in England,which has had long-lasting public health consequences,was avitamin Cdepletion study started in 1944,also at Sorby.This medical experiment involved 20 subjects,most of whom were conscientious objectors living in the building where many experiments,including the shipwreck experiment,were conducted.They were overseen by afuture Nobel Prize winner,and detailed data was kept on each participant in the study.“The vitamin Cexperiment is ashocking study,”said Philippe Hujoel,lead author of anew analysis of the Sorby vitamin Cexperiment,a practicing dentist and professor of oral health sciences in the UW School of Dentistry.“They depleted people’s vitamin Clevels long-term and created life-threatening emergencies.It would never fly now.”Even though two trial participants developed life-threatening heart problems because of the vitamin Cdepletion,Hujoel added,none of the subjects were permanently harmed,and in later interviews several participants said they would volunteer again given the importance of the research.Because of the war and food shortages,there was not enough vitamin Cavailable,and they wanted to be conservative with the supplies,explained Hujoel,who is also an adjunct professor of epidemiology.The goal of the Sorby investigators was not to determine the required vitamin Cintake for optimal health;it was to find out the minimum vitamin Crequirements for preventing scurvy. 查看详细>>

Using data from two large,long-running study projects in the Puget Sound region—one that began in the late 1970s measuring air pollution and another on risk factors for dementia that began in 1994—University of Washington researchers identified alink between air pollution and dementia.In the UW-led study,a small increase in the levels of fine particle pollution(PM2.5 or particulate matter 2.5 micrometers or smaller)averaged over adecade at specific addresses in the Seattle area was associated with agreater risk of dementia for people living at those addresses.“We found that an increase of 1microgram per cubic meter of exposure corresponded to a16%greater hazard of all-cause dementia.There was asimilar association for Alzheimer’s-type dementia,”said lead author Rachel Shaffer,who conducted the research as adoctoral student in the UW Department of Environmental&Occupational Health Sciences.The study,published Aug.4 in the journal Environmental Health Perspectives,looked at more than 4,000 Seattle-area residents enrolled in the Adult Changes in Thought(ACT)Study run by Kaiser Permanente Washington Health Research Institute in collaboration with UW.Of those residents,the researchers identified more than 1,000 people who had been diagnosed with dementia at some point since the ACT Study began in 1994.“The ACT Study is committed to advancing dementia research by sharing its data and resources,and we’re grateful to the ACT volunteers who have devoted years of their lives to supporting our efforts,including their enthusiastic participation in this important research on air pollution,”said Dr.Eric Larson,ACT’s founding principal investigator and asenior investigator at KPWHRI.Once apatient with dementia was identified,researchers compared the average pollution exposure of each participant leading up to the age at which the dementia patient was diagnosed.For instance,if aperson was diagnosed with dementia at 72 years old,the researchers compared the pollution exposure of other participants over the decade prior to when each one reached 72.In these analyses,the researchers had to account for the different years in which these individuals were enrolled in the study,since air pollution has dropped dramatically in the decades since the ACT study began. 查看详细>>

A study published June 16 in Biotropica by ateam of researchers at the University of Washington,the UW Burke Museum of Natural History and Culture,WWF Hong Kong and the University of Colombo has provided an important road map to conserving rough-nosed horned lizards in Sri Lanka.Rough-nosed horned lizards,or Ceratophora aspera,are small lizards that live in Sri Lankan rainforests and aren’t found anywhere else in the world.Characterized by the prominent horn in males,rough-nosed horned lizards live in moist,humid microhabitats in rainforests and palm groves.These lizards are particularly well-suited to understand the consequences of rainforest habitat destruction,climate change and the pet trade,as they are found throughout the lowland rainforests of Southwestern Sri Lanka.By analyzing the certain types of mutations in the genome of these lizards,the team was able to determine how geography and historical events impact the distribution of the remaining wild populations of rough-nosed horned lizards.Recent UW graduate Shanelle Wikramanayake led the study as part of her undergraduate work,and is now completing her master’s degree at California State University,Northridge.The team acquired DNA from the rough-nosed horned lizards by acatch-and-release approach of capturing wild lizards and taking tissue samples from the tips of their tails before releasing them back to the wild,which minimizes stress to the animals.Samples were taken across eight forests representing four forest groups from July through September 2018 and 2019,respectively.The remaining tissue samples will be housed along with photos of the lizards at the Department of Zoology and Environment Sciences at the University of Colombo.In addition,the DNA analysis from the team’s work is also available online,where the samples and analysis are available for other researchers around the globe to study. 查看详细>>

The University of Washington today signed amemorandum of understanding with the Aga Khan University to codify partnership activities already underway and to leverage complementary strengths to further expand research,service and education in low-and middle-income countries.The agreement was signed by UW President Ana Mari Cauce and Aga Khan University President Firoz Rasul.Representing the Aga Khan Development Network were Prince Rahim Aga Khan and Princess Salwa Aga Khan,nee Kendra Spears,UW Class of‘12,and AKU Provost Carl Amrhein.The Princess played akey role in encouraging the nascent partnership.“We are honored to partner with Aga Khan University to advance the health and well-being of communities around the globe.By combining our respective strengths and shared values,we can be apowerful force for creating access to healthcare and education,as well as supporting research and discovery,”Cauce said.Early collaborative activities between UW and AKU have included the launch of apaid international internship program with positions in Africa and Asia for UW students,joint projects to build research capacity in HIV/AIDs and HPV,and arange of other faculty collaborations. 查看详细>>

The National Science Foundation announced on Sept.11 that it is awarding grants totaling$8.5 million to 19 collaborative projects at 23 universities for the study of complex and entrenched problems in data science.Three of these projects will be based at the University of Washington and led by researchers in the College of Engineering and the College of Arts&Sciences.The grants build on 2017 awards in the Transdisciplinary Research in Principles of Data—or TRIPODS—program.These new grants make up the TRIPODS+X program,which expands these big-data projects into broader areas of science,engineering and mathematics.The lead faculty on these new projects are among the core founding faculty of the Algorithmic Foundations of Data Science Institute,the UW’s TRIPODS institute.“The multidisciplinary approach for addressing the increasing volume and complexity of data enabled through the TRIPODS+X projects will have aprofound impact on the field of data science and its use,”said Jim Kurose,NSF assistant director for Computer and Information Science and Engineering.“This impact will be sure to grow as data continues to drive scientific discovery and innovation.”The TRIPODS program’s convergent and interdisciplinary approach emerged from the 2016 NSF TRIPODS workshop.Since then,the program has evolved into acommunity of institutes that share expertise and work together to advance the three NSF priorities central to TRIPODS:research,visioning and education.Research-track projects aim to develop new algorithms and fundamental approaches to data-driven challenges.Visioning projects focus on fostering collaboration across disciplines and help spawn well-integrated research teams that yield truly new perspectives.Education projects are pilot efforts that aim to drive workforce development in multiple disciplines and at multiple education levels.Each TRIPODS institute will have three years to use its award to expand efforts in one of these program tracks. 查看详细>>