This week’s new questions

Which animal has the most sensory access to reality?

Susan Williams
Lakewood, Colorado, US

Given the worldwide impact of carbon dioxide, why is it still used to put the fizz in water and soft drinks?

Ian Tindal
Seaton, Cornwall, UK

Last Word is New Scientist’s long-running series in which readers give scientific answers to each other’s questions, ranging from the minutiae of everyday life to absurd astronomical hypotheticals. To answer a question or ask a new one, email lastword@newscientist.com

To answer this question – or ask a new one – email lastword@newscientist.com.

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