# Why Is Yawning Contagious?

Canonical: https://www.bookquiver.com/francesca-gould/why-is-yawning-contagious/9780749951580

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- Book: [Why Is Yawning Contagious?](https://www.bookquiver.com/francesca-gould/why-is-yawning-contagious) ([Why Is Yawning Contagious?.md](https://www.bookquiver.com/francesca-gould/why-is-yawning-contagious.md))
- Authors: [Francesca Gould](https://www.bookquiver.com/francesca-gould)
- Publisher: piatkus
- ISBN: 978-07-4995-158-0
- Pages: 1
- Published: 2007-10-25
- Language: en_GB
- Binding: Softcover

## Description

Everything you ever wanted to know about the human body - and some things you'd rather not... A wonderfully entertaining yet authoritative treasure trove of facts about our anatomy - it answers all the questions about our bodies we're usually too embarrassed to ask.· Why is yawning contagious? Some experts think that yawning may have developed as a means of communication. It may, for example, be a way of signalling to others that it's important to remain alert and stay awake in a certain situation. Another theory is that our early ancestors used it as part of their social behaviour, and as a way to help build a bond with the rest of the group.· Why are bogies green? When white blood cells meet germs, they make a large amount of an enzyme called myeloperoxidase, which is green because it contains a lot of iron. The colouration therefore comes from the iron.