site is arguably our most dominant human sense. The sense that we rely on most.

I really value my sight and I find it hard to imagine what life must be like

without the ability to see the world around you. But according to the World Health

Organization, there are roughly 36 million blind people in the world and a total of 1.3 billion who have some form of visual impairment.

For many losing your sight is a big deal.

Of course, there are many animals which have evolved

to be active at night, or in dark environments,

such as in caves or in the deep ocean,

and its sound they use,

not only to communicate with one another but also to navigate.

Many bats species have really mastered this art of navigating and hunting using sound instead of sight.

And the way they do this is now inspiring scientists and designers to come up with ideas which might offer more help to

blind and partially sighted people. I'm Patrick I with 30 Animals that Made A Smarter, an original podcast from the BBC

World Service that explores some of the amazing ways in which animals have solved

human problems.

If you've enjoyed the story so far, then please do spread the word and remember we want

your expertise too.

What examples do you have when it comes to animal inspired

designs? We'd love to hear from you. Please email us at 30 animals at BBC.com

or you can contact us via our website

BBC World Service.com slash 30 animals.

You can see our privacy notice there too. Well now in this episode number five, Bat and Visual Aids.

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