Invisible Dust

London | Monday 23 July
Pollution level: Moderate

Grey Long Eared (© Hugh Clark / Bat Conservation Trust)

Bats hear in 3D and may “hear in colour” according to Prof. Richard Dawkins.

Human hearing ranges 15 to 20 kHz depending on age. In comparison, some bats can hear sounds up to 110 kHz. Bats make calls as they fly, and listen to the returning echoes to build up a sonic map of their surroundings (echolocation). The bat can tell how far something is by how long it takes the sounds to return to them.

Here’s a little playlist we put together – feel free to add your own bat video to it!

Although Britain’s 18 species of bat are protected, an estimated 70% of UK bat populations were lost last century and are yet to recover. Professor Kate Jones, UCL (University College London) has studied bats for over 20 years and is the Chair of the Bat Conservation Trust and director of iBats . “Bat numbers are declining globally and our new technology lets us track populations better and learn much more about their fascinating sounds”.

Greater Horseshoe (© Gareth Jones / Bat Conservation Trust)

Interesting bat facts:

1: Scientists have found a trade off between brain size and testicle size in bats – so smarter bats have smaller balls.

2: The 30 million Mexican free-tailed bats from Bracken Cave in Texas (near where Jeremy Deller’s film Memory Bucket is set) eat 250 TONS of insects every summer night.

3: Most bat mothers give birth to only a single pup each year, making them very vulnerable to extinction. Bats are the slowest reproducing mammals on earth for their size.

4: The world’s smallest mammal is the bumblebee bat of Thailand, which weighs about as much as 5p piece and is critically endangered due to habitat loss.

5: The pallid bat of western North America is totally immune to the stings of the scorpions and centipedes upon which it feeds.

6: There are over 1200 known species of bats, just about 20% of all mammal species. Most of these bats are small enough to fit in the palm of your hand

7: Many important agricultural plants, like bananas, peaches, breadfruit, mangoes, cashews, almonds, dates and figs rely on bats for pollination and seed dispersal.

8: All bats can see, however they have developed the use of echolocation for navigating and hunting at night. The echoes of their high-frequency sounds bounce back from even the smallest objects, giving them an exact location, size and even texture.

9: Relative to body size bats testicles are around 8 times the size of human testicles.

10: Vampire bats adopt orphans, and are one of the few mammals known to risk their own lives to share food with less fortunate roost-mates.

Bats in Space is supported by Arts Council England.