Why do dogs love to play with trash? – Sarah G٫ age 11٫ Seguin٫ Texas
When I think about why dogs do something, I try to imagine what motivates them. What does a dog get out of playing with trash? As a veterinarian and a professor who teaches college students about companion animals, I believe there’s an easy answer: Garbage smells delicious and tastes good to dogs.
Dogs have an amazing sense of smell. They have 300 million receptors for smell in their noses, while humans have only 6 million. People can make use of this sniffing ability to train dogs to detect illegal drugs, explosives and endangered species, and to help locate people lost in the woods.
While you might not like how your trash smells, to your dog it is an appealing buffet brimming with apple cores, banana peels, meat scraps and stale bread. Even used napkins and paper towels are tempting to dogs, when they are smeared with and carry the smell of yesterday’s lunch.
Because dogs can find trace amounts of explosives or a person buried under 6 feet (1.8 meters) of snow after an avalanche, they are certainly capable of locating last night’s pizza crust and chicken bones in the kitchen garbage can.
Sometimes it’s hard to see what the attraction is. My Australian cattle dog mix, Sparky, loves to eat used tissues – gross, right?
Even empty cans smell inviting to dogs. Trash cans in kitchens and bathrooms are often at their nose level, too, making for easy access. Add to that the fact that if the dog got into the garbage once and found something tasty, they will likely keep searching with the hope of being rewarded again.
A Colombian police officer uses a drug-sniffing dog to search packages of flowers prior to export at El Dorado International Airport in Bogota on Feb. 5, 2025. Raul Arboleda/AFP via Getty Images
Thrill of the hunt
Searching and digging around for food is natural for dogs because it provides some of the thrill of the hunt, even if they just ate and aren’t hungry.
The most successful prehistoric dogs ate the bones and scraps that humans left behind more than 10,000 years ago. Hanging around humans and their garbage was a way they could get plenty to eat. Even your pup today has some of those same old searching instincts.
While our trash has changed from the days of hunting and gathering, the discarded paper napkins, plastic wrappers and food scraps we throw away all still smell like food to dogs. And this scavenging behavior is still hardwired in our pampered pets. Although it may look to us like they’re playing, our dogs’ sniffing out and tearing things up from the trash and tossing them around mimics what their ancestors did when they tugged on and tore up an animal carcass they had found.
Many people take advantage of this instinct and use “snuffle mats” – cloth or paper where food is hidden – or puzzle feeding toys to keep their pups’ minds active. Having to hunt for and find their food helps them use their noses and sharpens their skills.
Annoying or even dangerous
While spreading trash all over the home may be natural for dogs, cleaning it up is no fun for the people they live with. And if your dog pokes its nose in a garbage can, it could be in danger. Eating plastic bags, string, chicken bones, chemicals or rotten food can cause blockages, diarrhea and poisoning. Commonly referred to as “garbage gut,” garbage poisoning can be life-threatening.
I’ve treated dogs that cut their tongues and mouths on cans or broken glass. I once performed surgery to remove a corncob from the intestines of a dog that had eaten it a month earlier. He was certainly relieved when he woke up.
How can you keep your dogs away from the trash?
It can be hard to train a dog to leave garbage alone, especially if they have found a tasty morsel or two by raiding the trash can in the past. I recommend that you invest in a garbage can with a lid closed by a latch that they can’t open. If that fails, you can put garbage – especially food scraps – out of reach in a closet, cupboard or behind a closed door.
My trash cans are all behind closed doors, and the bathroom doors are always shut, which also keeps my cat, Penny, from unrolling the toilet tissue. But that’s another story. Our kitchen trash is in a latched cupboard.
No one knows exactly what goes through dogs’ minds. And yet looking at what motivates your canine companion and how dog behaviors have evolved may help explain why these animals do the things they do.
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Cancer research in the U.S. doesn’t rely on a single institution or funding stream − it’s a complex ecosystem made up of interdependent parts: academia, pharmaceutical companies, biotechnology startups, federal agencies and private foundations. As a cancer biologist who has worked in each of these sectors over the past three decades, I’ve seen firsthand how each piece supports the others.
When one falters, the whole system becomes vulnerable.
The United States has long led the world in cancer research. It has spent more on cancer research than any other country, including more than US$7.2 billion annually through the National Cancer Institute alone. Since the 1971 National Cancer Act, this sustained public investment has helped drive dramatic declines in cancer mortality, with death rates falling by 34% since 1991. In the past five years, the Food and Drug Administration has approved over 100 new cancer drugs, and the U.S. has brought more cancer drugs to the global market than any other nation.
But that legacy is under threat. Funding delays, political shifts and instability across sectors have created an environment where basic research into the fundamentals of cancer biology is struggling to keep traction and the drug development pipeline is showing signs of stress.
These disruptions go far beyond uncertainty and have real consequences. Early-career scientists faced with unstable funding and limited job prospects may leave academia altogether. Mid-career researchers often spend more time chasing scarce funding than conducting research. Interrupted research budgets and shifting policy priorities can unravel multiyear collaborations. I, along with many other researchers, believe these setbacks will slow progress, break training pipelines and drain expertise from critical areas of cancer research – delays that ultimately hurt patients waiting for new treatments.
A 50-year foundation of federal investment
The modern era of U.S. cancer research began with the signing of the National Cancer Act in 1971. That law dramatically expanded the National Cancer Institute, an agency within the National Institutes of Health focusing on cancer research and education. The NCI laid the groundwork for a robust national infrastructure for cancer science, funding everything from early research in the lab to large-scale clinical trials and supporting the training of a generation of cancer researchers.
This federal support has driven advances leading to higher survival rates and the transformation of some cancers into a manageable chronic or curable condition. Progress in screening, diagnostics and targeted therapies – and the patients who have benefited from them – owe much to decades of NIH support.
The Trump administration is cutting billions of dollars of biomedical research funding.
But federal funding has always been vulnerable to political headwinds. During the first Trump administration, deep cuts to biomedical science budgets threatened to stall the progress made under initiatives such as the 2016 Cancer Moonshot. The rationale given for these cuts was to slash overall spending, despite facing strong bipartisan opposition in Congress. Lawmakers ultimately rejected the administration’s proposal and instead increased NIH funding. In 2022, the Biden administration worked to relaunch the Cancer Moonshot.
This uncertainty has worsened in 2025 as the second Trump administration has cut or canceled many NIH grants. Labs that relied on these awards are suddenly facing funding cliffs, forcing them to lay off staff, pause experiments or shutter entirely. Deliberate delays in communication from the Department of Health and Human Services have stalled new NIH grant reviews and funding decisions, putting many promising research proposals already in the pipeline at risk.
Philanthropy’s support is powerful – but limited
While federal agencies remain the backbone of cancer research funding, philanthropic organizations provide the critical support for breakthroughs – especially for new ideas and riskier projects.
Groups such as the American Cancer Society, Stand Up To Cancer and major hospital foundations have filled important gaps in support, often funding pilot studies or supporting early-career investigators before they secure federal grants. By supporting bold ideas and providing seed funding, they help launch innovative research that may later attract large-scale support from the NIH.
Without the bureaucratic constraints of federal agencies, philanthropy is more nimble and flexible. It can move faster to support work in emerging areas, such as immunotherapy and precision oncology. For example, the American Cancer Society grant review process typically takes about four months from submission, while the NIH grant review process takes an average of eight months.
Ted Kennedy Jr., right, and Jeff Keith raise money for the American Cancer Society in 1984. Mikki Ansin/Getty Images
But philanthropic funds are smaller in scale and often disease-specific. Many foundations are created around a specific cause, such as advancing cures for pancreatic, breast or pediatric cancers. Their urgency to make an impact allows them to fund bold approaches that federal funders may see as too preliminary or speculative. Their giving also fluctuates. For instance, the American Cancer Society awarded nearly $60 million less in research grants in 2020 compared with 2019.
While private foundations are vital partners for cancer research, they cannot replace the scale and consistency of federal funding. Total U.S. philanthropic funding for cancer research is estimated at a few billion dollars per year, spread across hundreds of organizations. In comparison, the federal government has typically contributed roughly five to eight times more than philanthropy to cancer research each year.
Industry innovation − and its priorities
Private-sector innovation is essential for translating discoveries into treatments. In 2021, nearly 80% of the roughly $57 billion the U.S. spent on cancer drugs came from pharmaceutical and biotech companies. Many of the treatments used in oncology today, including immunotherapies and targeted therapies, emerged from collaborations between academic labs and industry partners.
But commercial priorities don’t always align with public health needs. Companies naturally focus on areas with strong financial returns: common cancers, projects that qualify for fast-track regulatory approval, and high-priced drugs. Rare cancers, pediatric cancers and basic science often receive less attention.
Industry is also saddled with uncertainty. Rising R&D costs, tough regulatory requirements and investor wariness have created a challenging environment to bring new drugs to market. Several biotech startups have folded or downsized in the past year, leaving promising new drugs stranded in limbo in the lab before they can reach clinical trials.
Without federal or philanthropic entities to pick up the slack, these discoveries may never reach the patients who need them.
A system under strain
Cancer is not going away. As the U.S. population ages, the burden of cancer on society will only grow. Disparities in treatment access and outcomes persist across race, income and geography. And factors such as environmental exposures and infectious diseases continue to intersect with cancer risk in new and complex ways.
Addressing these challenges requires a strong, stable and well-coordinated research system. But that system is under strain. National Cancer Institute grant paylines, or funding cutoffs, remain highly competitive. Early-career researchers face precarious job prospects. Labs are losing technicians and postdoctoral researchers to higher-paying roles in industry or to burnout. And patients, especially those hoping to enroll in clinical trials, face delays, disruptions and dwindling options.
Researchers have been rallying to protect the future of science in the U.S. AP Photo/John McDonnell
This is not just a funding issue. It’s a coordination issue between the federal government, academia and industry. There are currently no long-term policy solutions that ensure sustained federal investment, foster collaboration between academia and industry, or make room for philanthropy to drive innovation instead of just filling gaps.
I believe that for the U.S. to remain a global leader in cancer research, it will need to recommit to the model that made success possible: a balanced ecosystem of public funding, private investment and nonprofit support. Up until recently, that meant fully funding the NIH and NCI with predictable, long-term budgets that allow labs to plan for the future; incentivizing partnerships that move discoveries from bench to bedside without compromising academic freedom; supporting career pathways for young scientists so talent doesn’t leave the field; and creating mechanisms for equity to ensure that research includes and benefits all communities.
Cancer research and science has come a long way, saving about 4.5 million lives in the U.S. from cancer from 1991 to 2022. Today, patients are living longer and better because of decades of hard-won discoveries made by thousands of researchers. But science doesn’t run on good intentions alone. It needs universities. It needs philanthropy. It needs industry. It needs vision. And it requires continued support from the federal government.
Note: The following A.I. based commentary is not part of the original article, reproduced above, but is offered in the hopes that it will promote greater media literacy and critical thinking, by making any potential bias more visible to the reader –Staff Editor.
Political Bias Rating: Center-Left
This article reflects a centrist-left perspective, primarily emphasizing the critical role of federal funding in cancer research and its vulnerability due to political shifts, particularly under the Trump administration. It also highlights the challenges faced by researchers and the urgent need for stable funding to maintain U.S. leadership in cancer research. While it acknowledges the importance of private and philanthropic contributions, it leans towards advocating for government involvement in maintaining a balanced and effective research ecosystem. The discussion of past funding cuts and their impact further signals a mild left-leaning concern over government policy changes.
Did you eat cereal this morning? Or have you walked on a gravel path? Maybe you had a headache and had to take a pill? If you answered any of these questions with a yes, you interacted with a granular system today.
Scientists classify any collection of small, hard particles – such as puffed rice, sand grains or pills – as a granular system.
Even though everyone has interacted with these kinds of systems, describing the physics of how the particles collectively act when they are close together is surprisingly hard.
Granular systems sometimes move like a fluid. Think of an hourglass where sand, a very typical granular material, flows from one half of the glass to the other. But if you’ve run on a beach, you know that sand can also act like a solid. You can move over it without sinking through the sand.
As a geologist, I’m interested in understanding when a granular system flows and when it has strength and behaves like a solid. This line of research is very important for many agricultural and industrial applications, such as moving corn kernels or pills in a pipeline or shoot.
Understanding when a granular system might flow is also essential for geologic hazard assessments. For example, geologists would like to know whether the various boulders making up the slope of a mountain are stable or whether they will move as a rockslide.
Transferring forces between grains
To understand the behavior of a granular system, scientists can zoom in and look at the interactions between individual grains. When two particles are in contact with each other, they can transfer forces between each other.
Imagine this scenario: You have three tennis balls – the grains in this experiment. You place the tennis balls in a row and squeeze the three balls between your hand and a wall, so that your hand presses against the first ball. The last ball is in contact with a wall, but the middle ball is free floating and touches only the other two balls.
Tennis balls can act as grains in this simple granular system experiment. When you push against the tennis ball on the end, you exert a force, which acts upon the other two balls and eventually the wall. Jeremy Randolph-Flagg
By pushing against the first ball, you have successfully transferred the force from your hand through the row of three tennis balls onto the wall, even though you’ve touched only the first ball.
Now imagine you have many grains, like in a pile of sand, and all the sand grains are in contact with some neighboring grains. Grains that touch transfer forces between each other. How the forces are distributed in this granular system dictates whether the system is stable and unmoving or if it will move – such as a rockslide or the sand in an hourglass.
On the left are photoelastic discs used for two-dimensional experiments (9 mm diameter), and on the right are photoelastic grains used for three-dimensional experiments (14 mm diameter). Nathan Coon
Tracking forces in the lab
This is where my research team comes in. Together with my students, I study how grains interact with each other in the laboratory.
In our experiments, we can visualize the forces between individual grains in a granular system. While all granular systems have these forces present, we cannot see their distribution because force is invisible in most grains, such as sand or pills. We can see the forces only in some transparent materials.
To make the forces visible, we made grains using a material that is transparent and has a special property called photoelasticity. When photoelastic materials are illuminated and experience force, they split light into two rays that travel at different speeds.
This property forms bright, colorful bands in the otherwise transparent material that make the force visible. The brightness of the grains depends on how much force a grain is experiencing, so we can see how the forces are distributed in the granular system. The particles themselves do not emit light, but they change how fast light rays travel through them when they experience force – which makes them appear brighter.
On side A is a three-dimensional photoelastic grain without force applied, while on side B is the same grain once force is applied. In this case, we just squish the grain from the top and bottom. The brighter green bands start at the top and bottom of the grain where the force is applied and are the result of the photoelastic property. Jacqueline Reber
Scientists before us have used photoelasticity to visualize force in granular materials. These previous experiments, however, have examined only a single layer of grains. We developed a method to see the forces in not just a single layer of grains but throughout a whole heap.
Observing the forces on the outside of the heap of grains is pretty easy, but seeing how the forces are distributed in the middle of the pile is a lot harder. To see into the middle of the granular system and to illuminate grains there, we used a laser light sheet.
To generate a laser light sheet, we manipulated a laser beam so that the light spread out into a very narrow sheet.
With this light sheet, we illuminated one slice throughout the granular system. On this illuminated slice, we could see which grains were transferring forces, similarly to the previous two-dimensional experiments, without having to worry about the third dimension.
We then collected information from many slices across different parts of the grain heap. We used the information from the individual slices to reconstruct the three-dimensional granular system.
This technique is similar to how doctors reconstruct three-dimensional shapes of the brain and other organs from the two-dimensional images obtained by a medical CT scanner.
In 3D photoelastic experiments, the cart system shown at the top left is used to obtain regularly spaced laser light slices of the experiments, with the middle being sliced. The bottom left shows a schematic on how multiple slices can recreate a 3D object. The right shows three consecutive photos that are 0.7 cm apart – roughly one grain’s radius. The bright green crosshatch pattern shows how the forces are distributed between the individual grains. Nathan Coon
In our current experiments, we’ve been using only a small number of grains – 107. This way we can keep track of every individual grain and test whether this method works to see the force distribution in three dimensions. These 107 grains fill a cube-shaped box that is about 4 inches (10 centimeters) wide, tall and deep.
So far, the experimental method is working well, and we’ve been able to see how the force is distributed between the 107 grains. Next, we plan to expand the experimental setup to include more grains and explore how the force changes when we agitate the granular system – for example, by bumping it.
This new experimental approach opens the door for many more experiments that will help us to better understand granular systems. These systems are all around you, and while they seem so simple, researchers still don’t truly understand how they behave.
Note: The following A.I. based commentary is not part of the original article, reproduced above, but is offered in the hopes that it will promote greater media literacy and critical thinking, by making any potential bias more visible to the reader –Staff Editor.
Political Bias Rating: Centrist
The article is a scientific explanation about granular systems, which focuses on explaining the behavior of small particles and their applications in various fields. It is a neutral, factual piece of writing that doesn’t present any political viewpoint or leanings. The content is focused purely on academic research and is free of any political commentary or bias, making it centrist in its approach.
As outside temperatures dropped to the low- to mid-teens Fahrenheit on Feb. 10, 2025, two children died of carbon monoxide toxicity in a family van parked in a Detroit casino parking garage.
We are political scientists who study urban and housing public policies, and in the months since this tragedy, we took a deep look at the trends in homelessness and housing policies that foreshadowed the events of that night.
More kids are experiencing homelessness
One important trend is that the number of homeless children in the city reached a record high in 2024. This is true even though the overall numbers of people experiencing homelessness in the city is declining overall.
Most of these children were unhoused but considered sheltered because they had a place to sleep in an emergency shelter or transitional housing, or were able to temporarily stay with family or friends.
Nineteen of the kids were unsheltered – meaning they were sleeping in places not designed for human habitation, like cars, parks or abandoned buildings.
A different set of data comes from the Detroit Public Schools. The district looked at the entire 2022-2023 school year and found that roughly 1 in 19 students were unhoused at some point during that nine-month period — more than double the number in the 2019-2020 school year.
A lack of temporary solutions
The lack of adequate funding and staffing in the city’s shelter system means unhoused people often struggle to access temporary shelter beds.
Children who experience housing insecurity are often caught in the middle of bureaucracy and failed regulation.
The mother of the children who died in February had reached out to the city in November 2024 when they were staying with a family member. The mother noted that she wanted to keep all five of her children together.
The long wait for shelter has contributed to the rise in people living on the streets or in their vehicles. The number of unsheltered individuals — including both adults and children — doubled from 151 in 2015 to 305 in 2024. This trend of increasing unsheltered homelessness contrasts with the overall decline in the total number of homeless people in the city, which is down from a peak of 2,597 in 2015.
Their access to stable housing depends on their parents and what the adults in their life are able to provide. As rents increase in the city, some children are left vulnerable.
Some landlords pass the expense of these regulations on to tenants, making housing less affordable. Others leave their properties vacant, pushing up prices by lessening the supply.
The current average fair market rent for a two-bedroom apartment in Detroit is $1,314 per month. For the typical household in the city, this basic shelter cost, not including utilities, makes up 41% of the household income.
For the lowest-income households, any unexpected expense can disrupt a delicate financial balance and lead to eviction and homelessness. Children in these situations often face major instability, moving between shelters – or, as in the case of the children who died in February, sleeping in cars.
Detroit’s stricter housing regulations may have improved conditions for some renters, but a report by Outlier Media shows that only 8% of landlords are in compliance, leaving legacy residents in subpar rentals at higher prices.
And these new rules have victims who are too often ignored until tragedy strikes.
Note: The following A.I. based commentary is not part of the original article, reproduced above, but is offered in the hopes that it will promote greater media literacy and critical thinking, by making any potential bias more visible to the reader –Staff Editor.
Political Bias Rating: Center-Left
This content exhibits a center-left political bias as it focuses on social issues like homelessness, housing insecurity, and the struggles faced by vulnerable populations, particularly children. The piece critiques systemic failures, such as inadequate funding and bureaucratic shortcomings, while acknowledging the role of government regulations and COVID-era funding. The tone emphasizes the need for public policy solutions and social support improvements, aligning with a center-left perspective that advocates for government intervention and social welfare enhancements without veering into far-left ideological framing or far-right critiques.
