Drug users aren't choosing dangerous fentanyl - they don't know what's in their drugs; Selfies for health - a smartphone app can detect anemia; Making it on the Moon - 3D printing useful stuff with moon dust; The octopus might have traded its shell for intelligence; Have researchers been wrong about Alzheimer's? A new theory challenges the old story; What would happen to Earth if there were no volcanoes?

Will the 'rogue science' that created genetically edited babies lead to backlash against research?; Mysterious fast radio bursts from space: Five explanations for what they could be; Spinal injury patients take steps again thanks to spinal pacemaker; A lack of scientific data behind medical implants could seriously hurt Canadians; That sounds funny - the science behind why certain words make us laugh; Canadian Astronaut David Saint-Jacques will get to watch the world go around.

Captive rearing can accidentally change animals so they may not survive in the wild; A new plane with no moving parts flies by electrifying the air; Scientist refutes notion that gender identity is an 'unscientific liberal ideology'; Mars-quakes may shake the red planet, and NASA's new lander will detect them; How bats and dolphins use their sonar when everyone's talking at once; How do birds find seeds?

An asteroid impact on Greenland left a massive crater under the ice; Will coral reef islands rise or fall? It's a greenhouse-gas paradox; How moths evolved a kind of stealth jet technology to sneak past bats; Tiny people have evolved in rainforests because it's where tiny steps are better; The mysteries of animal movement - how they walk on water and climb up walls; What are the visible changes in the night sky in the last 3,000 years?

We interrupt your usual Quirks & Quarks podcast feed with a little bonus this week. It's called "Tai Asks Why" and it's hosted by a curious young fellow named Tai Poole - an 11-year old! - who's on a mission to solve the mysteries of life, love and science.

The 'Trump of the Tropics' is now in charge of the lungs of the planet. Here's why that's scary; Probiotics probably aren't making you well, and they could make you sicker; The biggest bird in history might have been blind as a bat; A step towards Optimus Prime - transforming robots can reshape themselves; Aged chocolate: Archeologists find evidence of 5000 year old chocolate drink; Why are salt water fish not salty to eat?

Neanderthals nursed their sick and injured back to health with ancient medicine; Listen to the Antarctic ice sheet sing a song of melting ice; There's a catch to 'catch and release:' hook injuries interfere with fish feeding; Purple reign: life on Earth might once have been dominated by purple micro-organisms; Evolution is going uptown as plants and animals adapt to city life; Why is the sound we hear in two ear buds not twice as loud as the sound from one?

Canada's latest Nobel winner is a 'laser jock' who loves the lab; Researchers are reading doctors' brains to see how good they are at surgery; 'Smelling' for shark DNA to see if it's safe to go back in the water; Watching a moon rise - in a solar system 8000 light years away; Thousands of women with autism may be going undiagnosed because it's a 'male disorder'.

What this man with narcolepsy can teach us about getting better sleep; Bird song is unique as well as beautiful - no other animal makes noise this way; 'Nuclear pasta' on a neutron star could support mountains centimetres tall; How manta rays eat could be the secret to filtering pollution from water; No more sunburns: a simple wristband helps us get just the right amount of sun; Why is bird poop white?

We can forecast the hurricanes. Can we figure out how to forecast their floods?; Octopuses on ecstasy: The party drug leads to eight-armed hugs; The Sahara's wind and sun could power the world, and turn the desert green; The Gulf of St. Lawrence is running out of oxygen thanks to climate change; Elephant families are very like ours, according to the filmmakers of 'The Elephant Queen'; What happens when opioids are released into the environment?