I can probably Google these three questions, but I’m asking here just in case anyone happens to know a bit about this subject.
Q1. Bats and their echo location apparatus. One source says they can emit up to 100,000 clicks (for echo location) per second. This sounds so impressive it’s unbelievable. Is it true?
Q2. How large is a bat’s brain? And what would be a good way of conveying it with a simple, memorable comparison, e.g. “it’s about the size of half your top-most little finger (‘pinkie’) joint”.
Q3. How much larger is an average human brain than an average bat brain. 100 times? 500 times? 1000 times?
I find that a little unlikely. 100 kHz would probably close to the higher end of the frequency of the sound which makes up the click. I don’t see how a click could usefully be as short as the period of the sound wave. I think your source may have these two frequencies confused. Using a bat detector I have heared the clicks for several bat species common in the UK and would estimate the click frequency (as distinct from the frequency of the sound itself) between 1/sec and 100/sec. For some species the clicks speed up as the bat homes in on prey
For the smallest UK bat - the Pipistrelle - I think your example size could account for the whole head, let alone the brain.
Thanks for your helpful answer. So, it seems the figure I read was the frequency of the sound, not the number of sounds (clicks) per second. Imagine I’m a very simple, none too bright, non-science sort of person. Please explain what the ‘frequency’ means, if it doesn’t mean 100,000 of something happening per second.
No way. This site notes that some bats’ hearing ranges above 100 khz. But that’s the carrier frequency, not the number of clicks in a second.
I recently ran into a guy with a “bat detector” - an electronic circuit that makes bats audible. The bats he was listening to (Little Brown Bats) were emitting something like 2 to 3 clicks per second. When they located an insect, they’d shift to a sort of zzzzzzzzzzziiiiiiiipppp noise that lasted about a second and rose in frequency at it progressed. This apparently allows them to do precise homing as they attempt to capture dinner.
It does mean that 100,000 vibrations are happening in a second. A typical “click” probably consist of a few thousand of those vibrations.
For an analogy, when a singer hits the note of A, his vocal chords are vibrating around 440 times a second. (It would be rather more difficult for him to generate 440 separate notes in a second.)
To be pedantic, the vibrations are happening at the rate of 100,000 per second. But most of them don’t last as long as a second, so very few seconds contain as many as 100,000 vibrations.
Think of it in musical terms. There is the note the bat ‘sings’ and how rapidly it repeats that note. The bat sings at a very high pitch, maybe at 100 kHz (i.e. 100,000 cycles pre sec), and it repeats this note at maybe 100Hz.
Going by my Golden Guide To Bats Of The World, insectivorous bats top out at 200 clicks per second when moving in for the kill.
Ignoring megachiroptera and bumblebee bats, I’d say your safe with ‘size of pea’.
Why just focus on size? Some shaded graphics would help. OTTOMH, we’ve got a bigger, far more wrinkly cerebral cortex. Color all the parts we have and they don’t
I want this information for part of a spoken presentation that goes with a routine I use in my show. It’s not a suitable context to be introducing graphics and visual aids. I just wanted to mention something fascinating in the natural world about brain function, and I thought echolocation would be a good choice, and then follow it with a reference to how much larger the human brain is.