Atoms are the building blocks of our world. Many have been around since right after the Big Bang created the universe nearly 14 billion years ago. And if life on Earth is made of atoms that are from all the way back then... will those atoms keep existing forever? That’s what CrowdScience Listener Rob in Australia would like to know.

Caroline Steel investigates the immortality of atoms by travelling to CERN, the world’s largest particle physics laboratory located along the border of France and Switzerland. There, theoretical physicist Matthew McCullough explains whether the smallest atoms can decay or survive the test of time.

Physicist Marco van Leeuwen from Nikhef, the National Particle Physics Laboratory in the Netherlands, gives Caroline a behind-the-scenes tour of the ALICE experiment and the Large Hadron Collider at CERN. She learns how atoms are smashed at incredibly high speeds, and whether that might spell the end of an atom.

And all life on earth is made up of atoms, but how does a collection of tiny particles become a living being? Astrobiologist Betül Kaçar from the University of Wisconsin, Madison, breaks down how life works from an atomic point of view.

Presenter: Caroline Steel

Producer: Imaan Moin

Editor: Ben Motley

(Photo: Hands cupping a glowing atom in the studio - stock photo. Credit: Paper Boat Creative via Getty Images)

Listener Jude in Canada wants to know why some animals are black and white. Why do zebras risk being so stripy? Why do pandas have such distinct marking? And do they have something in common? Presenter Caroline visits Pairi Daiza, a zoo in Belgium. Together with her guide for the day, Johan Vreys, she looks at these weird and wonderful animals up close. First, she visits three zebras having breakfast. Ecologist Martin How from the University of Bristol explains his ingenious experiment involving horses with zebra blankets. Next on the tour is the giant panda which, according to Prof Tim Caro from the University of Bristol, looks at the way it does to camouflage in snowy forests in China. But there are many more animals to see, and many more reasons to be monochrome, including the penguin and its tuxedo-like colouration. Hannah Rowland, senior lecturer at the University of Liverpool explains that it might have more than just a single function. It turns out, scientific answers aren’t always black and white.

Presenter: Caroline Steel Producer: Florian Bohr Editor: Ben Motley

(Photo: The zebra was running gracefully running in the green water. Credit: Surasak Suwanmake/Getty Images)

Sometimes in science, when you try to answer one question it sparks even more questions.

The CrowdScience inbox is a bulging example of that. We get tons of new questions every week and many of those are following up on episodes we’ve made. Sometimes you want us to go deeper into part of the answer, or sometimes a subject intrigues you so much that it inspires further questions about it.

In this episode presenter Caroline Steel is on a mission to answer some of those questions.

The CrowdScience episode How do fish survive in the deep ocean? led listener Ivor to wonder what sort of vision deep sea fish might have. On hand to answer that is Professor Lars Schmitz, Kravis Professor of Integrated Sciences: Biology, at Claremont McKenna College in the USA

Sticking with vision, we also tackle a question inspired by the CrowdScience episode Do we all see the same colour? For years listener Catarina has wondered why her eyes appear to change colour. Professor Pirro Hysi, ophthalmologist at the University of Pittsburgh, sheds some light on that subject.

In India, Rakesh listened to the CrowdScience episode Will the Earth ever lose its moon? and wondered about Jupiter’s many moons. The European Space Agency’s Ines Belgacem is working on a new mission to study Jupiter’s moons. She explains which of the giant planet’s ninety seven moons are ones for Rakesh to watch.

We also hear how the episode Why can’t my dog live as long as me? caught the attention of listener Lisa... and her cat. She had us falling in love with the long history of falling cats and the scientists who study them. Caroline is joined by Professor Greg Gbur, physicist at the University of North Carolina, Charlotte in the USA and author of Falling Felines and Fundamental Physics.

Could this episode of follow up questions lead to an episode investigating the follow up questions to these follow up questions? Have a listen and, who knows, maybe you’ll find yourself inspired to email [email protected]

Presenter: Caroline Steel

Producer: Tom Bonnett

Editor: Ben Motley

(Photo: Innovation and new ideas lightbulb concept with Question Mark - stock photo Credit: Olemedia via Getty Images)

CrowdScience listener David is a bird whisperer.

On his family farm in Guinea, he would mimic the call of the black-headed weaver. He could replicate it so well that the birds would fly in close, curious to find out who was calling. David has been wondering if he was actually communicating with the weaver.

In the foothills of the Austrian Alps is a research hotspot with a curious history. It was here that a scientist first began studying birds in their natural environment. That work continues today with Andrew Katsis from the University of Vienna, who knows the local flock of greylag geese by name. His research shows that animals aren’t just anonymous members of a group, they have personalities, relationships, and the ability to recognise one another.

But what else do birds know? Thomas Bugnyar, professor of social behaviour and animal cognition, spends his time trying to get inside the mind of ravens. His work suggests they can understand their surroundings, make rational decisions, and even solve complex problems.

Plus, we meet Ellie, a cockatoo with the ability to use a touchscreen computer to “talk.” She has a working vocabulary of more than 1,500 words. And when she presses a button, it would appear she is not just pecking at random, she is choosing purposefully, responding in ways that suggest birds may not only understand us, but communicate back.

Presenter: Caroline Steel Producer: Minnie Harrop and Harrison Lewis Series producer: Ben Motley

(Photo: Close up of Greylag goose with blue background Credit: Harrison Lewis, BBC)