CrowdScience

BBC World Service
CrowdScience

We take your questions about life, Earth and the universe to researchers hunting for answers at the frontiers of knowledge.

  1. 17 JAN

    Which animal has the biggest carbon footprint?

    Carbon footprints are a measure of how much we each contribute to the greenhouse gases that warm the Earth’s atmosphere. The global average of carbon dioxide emissions is nearly 5 tonnes per person per year, although it can be triple that in certain countries. But one CrowdScience listener in Ghana is wondering about the bigger picture. After all, humans aren’t the only species on this planet. So which other animal has the biggest carbon footprint? CrowdScience presenters Caroline Steel and Marnie Chesterton are on the case, examining and arguing over the animal that deserves the top spot for this title. Caroline, a vegan, points to the cow as the top contender, since the livestock sector produces 14.5% of total greenhouse gas emissions, and cows, whether as meat or dairy animals, are responsible for the majority of that. The team look at initiatives around the world to be more efficient with each animal out there. But maybe it’s time to put another sector in the spotlight? Pets. We love our dogs and cats but do their meat-based diets win them a place on the podium? From most loved to most detested, we look at the role that key pests play in upsetting the carbon budget. Could a small beetle with a large appetite for greenery be an unusual winner, thanks to the trees these pests destroy over their lifetimes? Is the biggest offender a carbon footprint, hoofprint, pawprint, or clawprint? Presenters: Caroline Steel and Marnie Chesterton Producer: Marnie Chesterton Editor: Cathy Edwards Production co-ordinator: Ishmael Soriano Technical producers: Sarah Hockley and Donald MacDonald

    29 min
  2. 10 JAN

    Is beer better without alcohol?

    In the past stout beer has been touted for its supposed health benefits. Is there any truth to those claims - and what happens if you take the alcohol out? CrowdScience listener Aengus pondered these questions down at the pub, after noticing most of his friends were drinking non-alcoholic beers. He wondered how the non-alcoholic stuff is made – what’s taken out and what’s added in – and whether the final product is better for you than the alcoholic version. It’s a question that takes us to Belgium, home to the experimental brewery of a global drinks company which takes the growing market for alcohol-free beer very seriously. David De Schutter, head of research and development, shows host Marnie Chesterton how to take alcohol out of beer without spoiling the flavour. We also find our way to a yeast lab in Leuven, Belgium where Kevin Verstrepen and his team have found another way to make alcohol-free beer with the help of industrious microbes: yeast varieties that brew beer without producing any alcohol in the first place. And how do they compare to the alcoholic versions? We discuss the importance of aromas in our perception of beer’s taste. So should listener Aengus stick to non-alcoholic stout? We speak to scientist Tim Stockwell about the health drawbacks of alcohol, even in moderation. And gut microbiome researcher Cláudia Marques fills us in on her delicious pilot study, which looked at the effects of both non-alcoholic and alcoholic beers on our digestive tract. Along the way, Marnie taste-tests what's on the market, and asks the experts why this particular grocery shelf has become so much bigger and more flavourful in recent years. Presenter: Marnie Chesterton Producer: Sam Baker Editor: Cathy Edwards Production co-ordinator: Ishmael Soriano Technical producers: Giles Aspen, Andrew Garratt and Donald MacDonald (Image: Close-up of waitress holding craft beer at bar, Brazil Credit: FG Trade via Getty Images)

    33 min

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We take your questions about life, Earth and the universe to researchers hunting for answers at the frontiers of knowledge.

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