CrowdScience

Our species started in Africa, but what was the last habitable landmass we reached? CrowdScience presenters Marnie Chesterton and Geoff Marsh team up to investigate how and when our species journeyed around the world and settled its most far flung landmasses. Geoff heads to some ancient caves in Israel to investigate the ‘false starts’ humans made out of Africa, and Marnie speaks with Professor Lisa Matisoo-Smith in New Zealand, uncovering the development of Polynesian sailing canoes and how they enabled the last landmasses to be found by people. This is a story spanning over seventy thousand years, huge changes in culture and technology, and the repeated remodelling of the earth thanks to the ice ages. Produced by Rory Galloway (Photo: Polynesian canoeists at sunset. Credit: Richmatts/Getty Images)

It’s the sort of plot you would expect from a classic sci-fi movie; what if there are viruses trapped deep in Antarctic ice that could wreak havoc on humans? Crowdscience presenter Alex Lathbridge puts on warm gloves and meets the scientists venturing into the icy wilds. He wants to answer listener Tony’s question - can viral life exist in such inhospitable climes and if so, might it pose us a danger? Alex meets teams who venture to the Antarctic to find out about how their work to understand climate change leads them to drilling and analysing ice cores that are tens of thousands of years old. He then visits a dynamic husband and wife duo in France who are extracting viruses from 30,000 year old Siberian permafrost and bringing them back to life. He discovers that - rather than killing us all, - their findings of novel giant viruses might contribute to medicine and our understanding of evolution.(Photo: Scientists working in a laboratory. Credit: Getty Images)

Waste, trash, garbage – whatever you call it, unwanted materials have become a major presence in many of our lives and our environment. Every year it is estimated that humans around the world produce 2 billion metric tonnes of waste. Listener Clare from Devon in the UK wants to start tackling this herself. She would like to know if she can not just sort but process all her own recycling at home.Presenter Marnie Chesterton attempts to find out by asking the professionals. She heads out to an industrial-scale recycling plant to see if any of their gear could work in our homes, hears from reporter Chhavi Sachdev how waste collectors in Mumbai, India have to balance thrift with risk, and asks environmental engineer Jenna Jambeck whether she thinks solely domestic recycling is possible.(Image: Garbage bags with various bits of recycling, iron, paper and plastic. Credit: Getty Images)

The ritual of burying the dead stretches back to the obscure beginnings of human history - and perhaps beyond, with archaeologists uncovering evidence of burials that pre-date our own species. But why do we bury our dead? How important is it, and how did the practice evolve? CrowdScience listener Moses from Uganda began pondering these questions after attending a close relative’s funeral.We search for clues in some of the earliest known burial sites, compare other methods for dealing with human remains, and explore how the funeral practices around the world today compare to those of our ancestors. Did these rituals originally develop for reasons of simple hygiene, or are religious and symbolic aspects the real key to understanding them?Presented by Anand Jagatia Produced by Cathy Edwards for the BBC World Service(Photo: A bereaved young woman in black, taking flowers to a grave. Credit: Getty Images)

When CrowdScience listener, Grady, crashed violently on his motorbike in the desert, he thought he was going to die. Years later he still can’t remember the dramatic seconds just before the impact. Where did the memory disappear to? Did the hard hit to the head knock his memories out or are they still in his brain somewhere? CrowdScience turns to brain science to find out if those last few seconds are lost for good or if the brain tells a different story. Under normal circumstances our brains like to hold onto memories that are emotionally important to us. We can remember our wedding day but not yesterday’s breakfast. But scientists have discovered that during near-death experiences, our brains are flooded with chemicals that disrupt our ability to remember. Grady may never recall how he was able to keep his motorbike steady as he drove off the road because – maybe – the memory was never created in the first place.Presenter: Marnie Chesterton Producers: Melanie Brown and Louisa Field Sound design: Eleni Hassabis(Image: A biker helmet lies on street near to a motorcycle accident. Credit: Getty Images)

Magma is the hot, molten rock found beneath the Earth’s crust. It’s so plentiful that it got Greek listener Dimitrios wondering whether we could harness this heat. Could we drill directly into the magma and use it to power our homes, he asks presenter Marnie Chesterton? And from Ghana, Madock also got in touch with CrowdScience to ask why there are lots of volcanoes in some areas of the world, but then none in others?Marnie dispatches Anand Jagatia to Kenya, a country that is one of the biggest providers of geothermal energy in the world and home to the East African Rift system. At 4,000 miles long, a string of volcanoes sits along this fault line. Anand hikes up one of these to find out why volcanism is so active here. Anand then travels to a geothermal power plant to get to grips with how conventional geothermal energy works, before turning to Iceland, where they’ve drilled directly into magma - albeit by accident. What they discovered was supercritical steam. It’s neither a liquid nor a gas but holds up to 10 times more energy than both. And to find it naturally occurring is the ‘holy grail’ of geothermal power. But can our equipment stand such temperatures? Presenter: Anand Jagatia and Marnie Chesterton Producer: Graihagh Jackson(Image: A volcano erupts. Credit Getty Images)

Birds are dinosaurs, but did their extinct relatives move, look, or even sing like their avian relatives? From revealing the hidden information within fossilised dinosaur footprints, to reading the messages left by muscle attachments on fossil bones and seeing how modern palaeo-artists have started to draw fluffy feathered Tyranosaurs, presenter Geoff Marsh starts to reimagine dinosaurs as living animals. Beginning with CrowdScience listener Malcolm asking about hopping dinosaurs while on a fossil finding mission with world expert Dr Peter Falkingham, Geoff explores the vaults of the Natural History Museum with Dr Susie Maidment and meets palaeoartist Dr Mark Witton’s pet dinosaurs in his living room studio. Producer: Rory Galloway(Image: A Velociraptor dinosaur. Credit to Mark Witton)

CrowdScience goes interstellar this week to answer listeners’ questions about the future of space travel. Marnie Chesterton heads to Nasa’s Kennedy Space Centre in Florida, where she hears about the engineering challenges of creating a spacecraft that could eventually take us all the way to Mars. Then there are the challenges of engineering the humans for that momentous journey. In space, no-one can hear you scream, which is probably a good thing if you’re going to be trapped in a metal box for two years with the same people, as you cruise through the void on your way to the red planet. So how do astronauts prepare for the physical and psychological impacts of long-term space travel? We also discover how space travel can be made greener and cleaner as the European Space Agency implement the next phase of their plan to tackle the millions of pieces of space debris floating around our planet that potentially, could impact a mission before it even leaves Earth orbit.(Image: An astronaut in outer space. Credit: Getty Images)

Wouldn’t it be great if you could lose weight and stay fit just by exercising your brain? Trouble is everything takes so much effort - from burning off excess weight to powering our cars. But why?Presenter Marnie Chesterton rummages through the CrowdScience inbox to tackle all your energy-expending queries. Is the entire universe spinning? How much energy do we expend when sleeping? Can I think myself thinner? Scientists Helen Czerski, Andrew Pontzen and Andrea Sella join listeners from around the world to discover how effort and energy affect our lives.(Image: A young boy sits at an office desk searching for successful ideas using a homemade thinking cap with a lit up light bulb. Credit: Getty Images)

Loving someone who doesn’t love you in return makes us feel wretched – can science explain why we must suffer? Parental love makes perfect evolutionary sense but romance just seems to have it in for us time after time. CrowdScience listener Leja wants to know why we fall in and out of love. Marnie Chesterton discovers the irrational things, the impulsive things and the financially ruinous things BBC World Service listeners have done in the name of love and meet the rapper who turned herself into a science subject in an effort to flush out thoughts of her ex-boyfriend.We delve into our ancestral past and into our brains to find out why romantic love is so central to the human experience.Presenter: Marnie Chesterton Producer: Louisa Field(Image: A loving couple hugging each other, the woman holding a rose. Credit: Getty Images)