Check out our podcast feed for shows you might have missed, or visit us online at cbc.ca/quirks to see our on-demand audio archive.

Christ Kennedy from Moncton, New Brunswick asks: If someone had the means to, how close could we bring the Moon to the Earth while still keeping it in orbit around us? And fast would a month fly by?

Answer from Brett Gladman, a professor of astronomy at the University of British Columbia,

Matoli Degroot from Manitoba asks: Do animal species in the wild get bigger over time, since the bigger males would end up mating more than the smaller ones?

Answer from Danielle Fraser, head of paleobiology at the Canadian Museum of Nature in Ottawa.

Bill Sullivan from Hamilton, Ontario asks: Why does the hair on my head turn grey while hair on the rest of my body does not change colour?

Answer from Frida Lona-Durazo, a postdoctoral fellow in computational genetics at the University of Montreal, who’s studied the genetics of hair colour.

Dan from Quebec City asks: We know that the Earth’s crust is built of plates that float on the molten centre of the Earth. What is the force that moves those plates?

Answer from Alexander Peace, an assistant professor in the School of Earth, Environment and Society at McMaster University in Hamilton, Ont.

Frances Mawson from Heckmans Island in Nova Scotia asks: Prey animals like deer are intermittently forced to flee from various predators. When danger has passed, they pause for a moment and then resume browsing. How can they recover so quickly? 

Answer from wildlife ecologist and Western University professor Liana Zanette.

Richard Lukes from Winnipeg asks: As a hydro generating station generates energy, what is the effect on the downstream water? Has the temperature of the water been lowered? If so, then could hydropower help to cool the oceans and combat global warming?

Answer from Jaime Wong, an Assistant Professor in the Faculty of Mechanical Engineering at the University of Alberta.

Luc in Edmonton asks: With more people planting native grasses and plants around their houses and businesses in cities, will the bird population in these cities change or increase?

Answer from Sheila Colla, an Associate Professor in the Faculty of Environmental & Urban Change at York University and York Research Chair in Interdisciplinary Conservation Science.

John Ugyan from Kelowna, British Columbia asks: If atoms are 99.99% empty, why do our eyes see matter as if it was 100% solid? 

Answer from condensed matter physicist, Cissy Suen. who’s a joint PhD student from UBC’s Quantum Matter Institute and the Max Planck Institute for Solid State Research in Germany

Debbie Turner in Fenelon Falls, Ont. asks: How does climate change affect animals that hibernate?

Answer from Jeffrey Lane, an associate professor in the department of biology at the University of Saskatchewan.

Greg Hollinger from Owen Sound, Ontario asks: Since the planets orbit the sun in a plane, does their combined gravity pull on and distort the shape of the sun?

Answer from Roan Haggar, a postdoctoral fellow at the University of Waterloo’s Centre for Astrophysics.

What would you do with a third thumb? Research suggests our brain can quickly adapt  

Birds can dream - and even have nightmares - and now scientists are tuning in

A comprehensive new collection of medical information shows the health risks of space travel

A study in mice sheds new light on how exercise can reverse aging in the brain

Rare fossils from the ‘age of monotremes’ found in Australia 

How the brain can instantly tell the difference between speech and music

PODCAST EXTRAS

Organic farms next to conventionally farmed fields leads to increased pesticide use

Orca whales hunt, play and dive – one breath at a time

The secret of the beaver’s orange teeth can help us make our teeth strong

The sun’s ramping up its activity and now we have a better idea of what’s driving it

This spring we’ve seen some spectacular displays of northern lights and we’re expecting to see  more as we approach the peak of the sun’s natural cycle, the solar maximum. Every 11 years the sun cycles from having few sunspots on its surface to having many. Now according to a new study in the journal Nature, scientists have figured out what may be driving this process. Geoff Vasil, an associate professor of computational and applied mathematics at the University of Edinburgh, said instabilities in swirling magnetic systems near the sun’s surface gives rise to sunspots on its surface that can erupt and send solar storms our way.

Female otters use tools more than males – to crack open tasty treats and save their teeth

Otters are cute and clever – clever enough to be one of the few animals who use tools such as rocks, glass bottles, or even boat hulls to smash shells and access the tasty flesh inside. But researchers studying otters off the coast of California found that certain otters were using these tools more than others, and wanted to understand why. In a new study, published in the journal Science, research biologist Chris Law found that it was females that were using the tools more than the males, in order to access hard-shelled meals like clams and mussels without damaging their teeth.

The longest lasting human species (not us) were expert elephant hunters

Our cousins, Homo Erectus, inhabited Earth for nearly two million years, and they were capable hunters. An analysis of stone tool manufacturing sites, published in the journal Archaeologies, gives new insight into the high levels of organization and planning by these early humans. Tel Aviv University archeologist Meir Finkel studied the ancient stone quarries in the Hula Valley, and discovered that they were often located on elephant migration routes near water sources – so the humans didn’t have far to go to get weapons for slaying and butchering their meals. This triad of elephants, water and stone quarries is present across many Old Stone Age sites where the early humans lived, including South America, Africa and Europe. 

A plastic that carries the seeds of its own destruction

Researchers have been able to integrate spores of a plastic-eating bacteria into plastic to create a material that, over time, eats itself. In a controlled study, scientists found that the bacteria can break down 90 per cent of the soft plastic in the material in about 90 days. Mohammed Arif Rahman, a senior polymer scientist and R&D director of BASF, said they’re still working on it with hopes that the bacteria embedded within it will be able to keep on consuming the remaining plastic so as not to generate any microplastics. The proof of concept study was published in the journal Nature Communications. 

A new book about gravity celebrates failing and falling

When theoretical physicist Claudia de Rham didn’t quite make the cut as an astronaut candidate, she doubled down on her fascination with the phenomenon of gravity. This puts her on the path of great thinkers like Newton and Einstein who helped us to start to understand what holds the universe together. In a new book, The Beauty of Falling: A life in pursuit of gravity, she ties her personal adventures with her theoretical explorations of gravitational rainbows and the origins of dark matter, and details all the mysteries that still remain about this fundamental feature of reality.

Killer whales are likely ramming boats because they’re bored and having fun

Several years ago a small population of killer whales living off the coast of Spain began attacking boats, particularly sailboats, damaging some severely and even sinking a handful. While social media speculation has suggested whale rage as a cause, an international team of killer whale experts recently published a report suggesting the behaviour is not aggression, but is instead an example of these giant social creatures just playing and having fun with a toy. We speak with two contributors to the report: John Ford, research scientist emeritus at the Pacific Biological Station with Fisheries & Oceans Canada, and Renaud de Stephanis, the president of Spanish conservation group CIRCE.

4,000-year-old Egyptian skull shows signs of possible surgery for brain cancer

Researchers studying the history of cancer in human history recently hit the jackpot. In a collection of human remains at the University of Cambridge they found two skulls from Egypt, both thousands of years old, that show signs of advanced cancer. One of those skulls bore cut marks around the lesions. Lead study author and University of Santiago de Compostela professor Edgard Camarós said that regardless of whether these cuts were made as attempts at treatment or a post-mortem investigation, they show off the sophisticated medical knowledge of ancient Egyptians — and can also help better understand the evolution of cancer.This study was published in Frontiers in Medicine.

Gorillas’ tiny penises and low sperm count can help us understand infertility in humans

Gorillas are the biggest of the great apes, but their reproductive anatomy is diminutive. The males have small penises and testes, and low sperm quality. A new genetic analysis, published in the scientific journal eLife, identified the mutations that are responsible for male gorillas’ peculiar fertility. Vincent Lynch, an associate professor of biological sciences at the State University of New York at Buffalo, said these findings can help us better understand the genes responsible for lower sperm quality in humans.

1

Illuminating plumes of hot magma in the Earth’s mantle with earthquake seismic data

To understand the source of the magma fueling volcanic eruptions, scientists are using another significant geological event: earthquakes. The seismic waves that earthquakes send through our planet can shine a light on the chimneys of magma that connect the core of the Earth through the mantle to the surface. Karin Sigloch, a professor of geophysics at CNRS — France’s National Centre for Scientific Research, is part of an international effort to deploy seismic sensors throughout the oceans to illuminate the mantle plumes. Their research from recent observations in the Indian Ocean around Réunion Island was in Nature Geoscience. 

It’s intelligence all the way down: How cells, tissues and organs have their own smarts

We tend to think of collective intelligence as something we see among animals that work cooperatively to solve problems, like in an ant colony, a school of fish or flock of birds. But biologist Michael Levin, from Harvard and Tufts’ universities, thinks collective intelligence also extends to functions within the cell, all the way up to networks of cells, tissues and even organs. He suggests evolution has granted simpler biological layers in living systems the ability to flexibly solve problems. In a recent paper in Communications Biology, he argues we can harness these lower level problem-solving capabilities to make significant advances in regenerative medicine, and treating aging and disease.  

This little piggy escaped and wreaked havoc on crops and the environment

Wild pigs that have escaped or been released from farms have established self-sustaining populations in the prairies and central Canada and are wreaking havoc on farms and wilderness landscapes alike. A new study, led by Ryan Brook at the University of Saskatchewan, has tracked pigs to try to understand where, and how far, this porcine invasion can go. The research was published in the journal Biological Invasions.

Satellites and space junk burning up in the atmosphere is a new kind of pollution

Scientists doing high-altitude sampling of material deposited when meteorites burn up in the atmosphere are seeing a shift in the material they’ve been collecting. In a recent study in the journal PNAS, scientists found that increasingly the particles contain material that could have only come from vaporized space junk, such as the upper stages of rocket boosters and re-entering satellites themselves. Daniel Cziczo, an atmospheric scientist at Purdue University, said they’re now trying to find out what kind of impact this in material in the stratosphere may have on things like the ozone layer and global warming.

A 200 million year old marine reptile the size of a blue whale

Hundreds of millions of years ago, long before dinosaurs roamed the surface of our planet, ichthyosaurs ruled the Earth’s oceans. Analysis of bones found in a river basin in the UK suggests a new species might have been one the biggest marine animals that ever lived. Paleontologist Jimmy Waldron was part of the team, who published their research in the journal PLOS One. 

Fox skulls are optimized for diving into snow

Foxes hunt in winter by listening for rodents under deep snow and then leaping and diving into the snow, plunging down to snatch their prey. A team including Sunghwan Jung, a professor of Biological and Environmental Engineering at Cornell University, did a unique experiment to confirm that the pointed shape of the fox skull is better than any other shape they tested at penetrating deep into snow. The research was published in the journal PNAS.

Scientists propose a plan to study self-spreading vaccines

Researchers concerned with emerging diseases like H5N1 bird flu, which has devastated wild bird populations, are proposing a controversial way to stop the disease. Megan Griffiths, a postdoctoral researcher in viral ecology at the University of Glasgow, says transmissible vaccines would use harmless viruses to carry vaccines against pathogenic viruses. She’s the co-author of a recent study in the journal Science that presents a framework for how they could safely develop self-spreading vaccines.

The logic behind creating more dangerous viruses to understand them better

Anticipating how dangerous viruses — like avian influenza or coronaviruses — could transform from more innocuous forms into much more dangerous ones could help us prepare for future pandemics. Ron Fouchier, a molecular virologist at the Erasmus Medical Centre in Holland, says without doing “gain of function” research, like the kind he published in the journal Science in 2012, we never would have known which changes to lookout for with the current global H5N1 outbreak. Gain of function research, which involves experimenting with viruses to make them more dangerous, has become increasingly controversial, but Fouchier says with Europe’s strict regulations to ensure safety, the risk is worth the reward. 

The recent solar storm scrambled undersea sensors

The solar storm that lit up the evening sky with aurora recently was also detected by Canada’s Ocean Network system of undersea oceanographic observatories off both coasts of the country and up in the Arctic. The compass instruments that normally provide the direction of ocean currents fluctuated by as much as 30 degrees at the height of the solar storm and were picked up as deep as 2.7 kilometers. Kate Moran, the CEO and President of Ocean Networks Canada, said these measurements could prove to be useful for solar scientists to understand the depth of the impact geomagnetic storms can have on our electromagnetic field. 

Robots are stronger, and faster, and better – but still lose to animals

Despite being built to run, robots still can’t beat real animals in a race, says a new study published in Science Robotics. Researchers compared the physical abilities of animals to the latest generation of agile autonomous robots and showed that while they can exceed biology in strength and speed, robots still can’t match the performance of animals. Simon Fraser University professor Max Donelan explained that biology has better integrated systems, which makes animals able to respond faster to the situation at hand. 

How European brown rats took over North America

The brown rat is the clear undisputed winner of the rat race, having established ecological dominance in most cities across the continent. A new study led by Eric Guiry from Trent University involved analyzing piles of rat bones from dig sites and centuries-old shipwrecks to put together a timeline of when and how brown rats took over North America. He found that brown rats came across the pond much earlier than expected, and surprisingly dominated over black rats very quickly, even though the two animals weren’t actually in competition for the same food. The research was published in the journal Science Advances.

Decoding whale talk and primate calls 

Scientists are turning to technology to help decode animal communication. In the Caribbean researchers sorted rhythmic sperm whale clicks into an entire alphabet, while on land, machine learning algorithms revealed a new level of complexity in the calls of orangutans in Borneo.

Eavesdropping on nature sounds to save ecosystems in US National parks

In a basement at Penn State University, researchers with the Protected Areas Research Collaborative (PARC) Lab are listening to thousands of hours of recordings from the US National Park service in order to track every single noise - whether it be natural or human-made. This data is being used to understand how to preserve natural sounds in the parks, which have been shown to be beneficial to both humans, and wildlife. Now, the team is adopting machine learning and artificial intelligence to listen to more data than ever before. We spoke with co-principal investigator Peter Newman, and co-lab manager Morgan Crump. 

In a separate paper, recently published in Science Advances, researchers are calling attention to nature’s smellscapes—the various chemicals put out by trees and animals—and how they can affect humans. The multidisciplinary, international team, led by Gregory Bratman from the University of Washington, provides a conceptual framework for investigating nature’s smells, to fill in the gaps about what those scents are doing to humans, but also, to know what we’re doing to those scents.

Sabre tooth cats had baby-tooth backup

The fearsome canines of saber-toothed cats were terrific weapons for stabbing unfortunate prey, but their impressive length also made them vulnerable to breakage. A new study by University of California, Berkeley associate professor Jack Tseng suggests adolescent California saber-toothed cat kept their baby teeth to buttress the adult sabers, and reinforce them while cats learned to hunt. This research was published in The Anatomical Record.

Global warming could swallow Antarctic meteorites

Over 60 per cent of all meteorites found on Earth are discovered in Antarctica, embedded in the ice. But a new study published in Nature Climate Change cautions that the warming temperatures are causing the dark space rocks to sink below the surface before researchers can get to them. Glaciologist Veronica Tollenaar, who is the lead author of this study, says it’s important to collect as many of these meteorites as possible to avoid losing the insights they provide about the space around us. 

This worm’s eyes are bigger than its — everything

A pair of high-functioning eyes is perhaps not something you would associate with the various worm species on our planet. But down in the depths of the Mediterranean sea lives a small, translucent worm with alien-looking eyes that weigh more than twenty times as much as the rest of its head. Now, a group of vision researchers have found that their size is not just for show. Their vision works about as well as that of some mammals. Michael Bok, a researcher in the Lund Vision Group at Lund University in Sweden, said they may be using it to detect prey at night. They report their findings in the journal Current Biology.  

We’re breathing out an environment in which respiratory viruses may thrive

One of the questions that’s been raised by the COVID-19 pandemic is just what conditions allow viruses carried in aerosol droplets to survive and spread. A new study in the Journal of The Royal Society Interface found that a CO2 rich environment — like a crowded room with poor ventilation — makes the aerosol particles more acidic, which allows the virus to remain stable and survive longer. Allen Haddrell, a Canadian aerovirologist at the University of Bristol, said this means that CO2 levels don’t just tell you how well ventilated a room is, but it also tell how healthy the virus is in that air. 

Why an essential subatomic particle plays the field

The detection of the Higgs boson particle by the Large Hadron Collider in 2012 was one of the great moments for modern physics. But while many celebrated the discovery of the “God Particle,” physicist Matt Strassler was a bit frustrated by the way the particle discovery overshadowed what he said was truly important for our understanding of the universe: not the Higgs particle, but the Higgs field. In his new book called, Waves in an Impossible Sea: How Everyday Life Emerges from the Cosmic Ocean, he explains how the Higgs field literally makes the universe — and our place in it — what it is today. 

Listener Question — Do mated animals reject others crashing their relationships?

We hear the answer from Sarah Jamieson, a behavioural ecologist and assistant professor at Trent University.

We baby talk with both dogs and kids, but our faces say something different

Dogs can use their powerful noses to sniff out PTSD

A quarter of all Labradors are hard-wired to be hungrier and burn less energy

Your pet dog may know more words than you give them credit for

Size, face shape and other factors matter when it comes to a dog’s lifespan, study shows

It’s possible – and worthwhile – to teach an old dog new tricks

What a genome reveals about an extinct species of dogs - and the Indigenous people who cared for them

Chimpanzees are being forced to eat bat feces, and the viruses in it

Researchers in Uganda have noticed a new behaviour in the wild chimps they study. The apes are browsing on bat guano, apparently to access the nutrients it contains, as their normal source for these nutrients has been destroyed by humans. Since bats are carriers of a range of diseases, from ebola to coronaviruses, this may be a new way these diseases could spread. The study was published in Communications Biology. Dr Tony Goldberg, a professor of epidemiology at the school of veterinary medicine at the University of Wisconsin-Madison, was part of the team.

Controversial methods are working to buy Canada’s caribou some time

Woodland caribou have been in steady decline for decades, as logging, oil and gas exploration and other disturbances compromise their western mountain habitat. Steady progress has been made to restore habitat in order to save these caribou, but since these forests will take half a century to regrow, conservationists are trying a variety of interim actions to buy the caribou some time. A new study led by Clayton Lamb from the University of British Columbia Okanagan found that these methods, including direct feeding, maternal penning, and, controversially, culling predatory wolves, have helped caribou recover to some extent, but restoration of their habitat will be necessary for full recovery. The research was published in the journal Ecological Applications.

Giant ancient Pacific salmon had tusks sticking out of its face

Millions of years ago, enormous three metre-long salmon inhabited the seas of the Pacific coast. Named Oncorhynchus rastrosus, this ancient giant was first described in the 1970s as having long front fangs, which led to it being known colloquially as a “saber-toothed salmon.” But a new study published in PLOS ONE sets the record straight: the teeth actually protruded out to the sides from the fish’s upper jaw, as tusks do. Lead study author and Philadelphia College of Osteopathic Medicine professor Kerin Claeson says despite their menacing look, the salmon did not hunt with these tusks, since these strange fish were filter feeders.

The Gulf oil spill may have had ecological impacts we haven’t seen yet

Fourteen years ago an explosion destroyed the Deepwater Horizon oil rig and kicked off the largest oil spill in history. While commercial fisheries have largely recovered from the disaster, there are signs that rarer and more vulnerable species might have been devastated. Prosanta Chakrabarty from Louisiana State University surveyed deep sea fish catalogued in museum collections around the world and found that out of 78 endemic species found only in the Gulf, 29 of them haven’t been spotted in the years since the spill. The research was published in the Biodiversity Data Journal.

Primordial black holes may be the solution the problem of missing dark matter

The hunt for exotic black holes that Stephen Hawking first predicted back in the 1970s is now well underway. Primordial black holes behave just like any other black hole, but they would have  formed in the early universe and could  be any size. Many scientists are particularly interested in the primordial black holes that are the size of an atom and have the mass of an asteroid because they suspect they could be the answer for the missing dark matter in our universe. 

The climate is changing. So are we. On What On Earth, you’ll explore a world of solutions with host Laura Lynch and our team of journalists. In 1970, 20 million people showed up to fight for the environment on the first Earth Day. More than five decades later, is it time for this much tamer global event to return to its radical roots? 

OG organizer Denis Hayes recounts how – amidst other counterculture movements at the time – his team persuaded roughly one in ten Americans to take to the streets. As he approaches 80, Denis offers his singular piece of advice to the next generation of climate leaders. Then, environmental warriors Maria Blancas and Axcelle Campana share ideas on what a reinspired Earth Day could look like – including making it a public holiday.

More episodes of What On Earth are available at: https://link.chtbl.com/5zF03qcm

We love to hear from our listeners and regularly feature them on the show. Have a question or idea? Email [email protected]