Dr. Konstantina Stankovic

Subangstrom level.

Subangstrom level.

It's really phenomenal.

And another example to really highlight the sensitivity of this organ, if you have a trained violinist, if they move their finger by only a micron, so that's a millionth of a meter, right?

the ear can perceive that as a change in pitch.

You can't see that with your naked eye, but the ear can perceive it.

So these examples really highlight how delicate this organ is.

And another absolutely stunning thing about the ear is that there are these cells, they are sensory cells that we talked about, but they're called inner and outer hair cells.

And what's special about these outer hair cells, they actually move.

but they move at audio frequencies.

So what does that mean?

To put it in perspective, let's say that the heart beats at 60 beats per minute, which is one hertz.

If the heart starts beating at two hertz, 120 beats per minute, that's arrhythmia that could be life-threatening.

Well, these cells in the inner ear move in humans up to 20,000 hertz and in bats up to 100,000 hertz.

So this is to tell you how incredible this system is, and it's designed to let us detect sounds.

And it's evolved so that we can detect sounds at any point in a day or night.

Sound travels through any media.

Sound travels around obstacles.

It's really essential for survival.

There are species that don't even...