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.