Lifespan Sound Speed is an attempt to replicate the the way other animals hear.

Through speed percentage change based on a lifespan ratio calculation, the clip on the right acts as a kind of translation of the original field recording on the left.

It’s a little like imagining a robin the size of a person, but with the unit being the amount of moments in their life, instead of the amount of inches.

If life is a collection of moments, then maybe every living thing gets the same amount of moments in their lives - its just divided up differently. A bird, then, will have shorter moments than a human (divide 6 years and 80-something years into a million moments each, and theirs will be many seconds faster than ours) so its okay to slow the recordings down when we listen back, because each individual little whistle, one of many in the bird's call, might each be like a human sigh or shout.

What would they sound like if they heard with the same timing that we do?

This project was inspired by

a BBC piece named What might birdsong sound like in bird-time?,

as well as

Tom Lopez’s work with ZBS’s Dinotopia manipulating field recordings of other animals in order to sonically reintroduce dinosaurs to the anthropocene.

But the theory behind Lifespan Sound Speed is most directly explained in Hayao Miyazaki’s talk given to section three of the sixth grade class at Hachiman Elementary school, Sendai City, June 19, 1992, excerpted here:

When drawing picture for animation, we have to study how fast lots of different animals walk.
And if we were to look out the window and carefully observe how fast children of your age walk, we would find that it takes them about half a second to take one step.
So in other words, in one second you can take two steps.
When I'm really exhausted, I tend to think, "Wow I feel beat..." while I'm walking. And if you compare the speed I walk in the morning, when I've got lots of energy, with the speed at which I walk when I'm coming home at night, you'd see that I walk a lot faster in the morning.

Now, let's think about how fast a mouse walks. If a mouse only this big takes half a second per step, it will take him an awfully long time to walk from here to here. [Miyazaki points from one edge of the teacher's desk to the other.] Since mice can only take very small steps, at one half second per step the mouse would also be walking very, very slowly. But mice are actually really fast, right? Sometimes mice walk really slowly, but most of the time they're scampering about.
They're moving super fast.

Now what about elephants? When we're making an animated film and drawing picture of elephants walking, we have to think about long it takes an elephant to take a step. Take the example of a mammoth. Mammoths are like long-haired elephants, except that they were hunted to extinction long ago; when a mammoth took a step it didn't take half a second. Mammoths obviously walked much slower than that, but I think they probably could walk about as fast as a human, or even faster.

When we create animation, we draw twenty-four pictures for one second of film. So we always have to think about how we should use those twnty-four drawings to depict one second.

And after doing this sort of work for a long time, I realized that a human child takes half a second per step when walking, an elephant takes two seconds, and a mouse walks much, much faster. But I also began to realize that to the child, the elephant, and the mouse, they're all taking steps of the same relative length, so that to an elephant, a human, a mouse, or even a bee, what we think of as a second is experienced differently.

Now lets think of something on an even larger scale. Has anyone here heard of "mantle convection?" What? You haven't?" [laughter] Well, have you heard that entire continents actually move? You have, right? That's what we call mantle convection. At least, that's according to current scientific theories. We call the very center of the earth its core, and the mantle oozes out from somewhere between the earth's core and crust, slowly slithering and moving; it pushes the continents, which causes them to move. For example, the Japanese islands are apparently pushed around, little by little, by a part of the mantle called the Pacific Plate. And they say that this movement is what causes earthquakes, too.
Now how fast does the mantle move? Apparently about thirty centimeters a year. Of course, no matter how long and hard we stare at something moving thirty centimeters a year, there's absolutely no way that we can see it move.
We can't see it, but if you boys and girls were animals a thousand meters tall, or if you were giant living creatures made out of rock that lasted on average ten thougsand years - or, since thats probably not enough, a million years - you might actually be able to see the mantle move.

We live a hundred times longer than bees do. So, my personal interpretation of this is that, to these insects - which only live one-hundredth as long as a human - our one second probably feels like one hundred seconds. Of course, I don't know if this is really true or not, and it may be that I'm the only one who thinks this way. [laughter] In other words, if you write what I've said on your tests, you might flunk. But I like to imagine what it would mean if what I have said were really true.
You may have heard of the story Mitsubachi Māya no Bōken. The hero of the story is a honeybee, but the bee is almost like a human. Real honeybees of course don't actually carry pails to put honey in when they fly around, but this one does. I often imagine how different the world would look to a honeybee, if it were to see our one second as a hundred seconds. Of course, I haven't made such a film with a honeybee hero yet, but I'd love to do so someday.
I often wonder what rain would look like to our honey bee hero. What do you think it would look like? [Miyazaki points at a child in the front row; the child says, "I think the bee probably couldn't see the rain..."]
Really? But if one of our seconds feels like one hundred seconds to the honey bee, then to the bee a drop of rain would also seem to take one hundred seconds to fall the same distance that would only be one second to us. Yes? So instead of falling fast, the rain would seem to be falling very slowly, right? And when it rains we get wet, right? But I'll bet the bee doesn't get wet. The rain may seem to pour down to us, but it would seem slow to the bee, so I think the bee can probably avoid the drops. Bees flap their wings at an incredible speed, but to the bee, its wings probably seem to be flapping at roughly the speed we would see a walking person swinging their hands. And if that's the case, bees probably also see individual raindrops very clearly.
By the way, what sort of shape do you think raindrops really have? [Miyazaki asks a student to come up and draw a picture on the blackboard.] Right, that's how most people would draw them. But why do you suppose people draw them this way?
I think it's probably because humans can't see individual raindrops. And because we can't see them, we just imagine that, well, if water's going to fall out of the sky it must look like this. In other words, we're just drawing from our imagination. And it's because we humans don't have eyes like those of bees. But do you have any idea what water looks like if its released inside a spaceship? If water starts drifting in a weightless invironment, it gets all loopy, like this.
[Miyazaki demonstrates with hand gestures.]
The water gets all loopy while sort of collapsing at the same time. So when a bee flies through the rain it'd see one of these blobs over here, one way over there, and another way over there, too.
As it flew it'd have to weave its way through all these loopy blob things falling all about.
And if you made a cartoon film showing this, do you think everyone would know that these blobs are raindrops? Well, they probably wouldn't, right? [Children laugh and chime in with, "No, they wouldn't."]
But from the view point of the honeybee, I think the world would probably look like this. Don't you think so? [Miyazaki draws a picture.
The children marvel and say, "Maybe he's right..."]


Now, you can probably imagine all sorts of things if you start thinking this way. You've heard of giant tortoises, right? They're said to be some of the world's longest living animals, maybe living up to two hundred years. Well, the giant tortoises on the Galapagos Islands weat cactus, and I suspect that if they see a human walking by, that the human probably looks like they are walking awfully fast...


I can give you lots of other examples. By 1994, you'll all be in your first year of middle school, right? And you'll be in your second year by 1995. But that's really not much time at all for us grown-up animators, because by the spring of 1993 we really start to get nervous and feel the heat. We really feel like we're running out of time....
[Amazed children exclaim, "You're kidding!"]
Believe me, a year's really not enough to create a two-hour animated film. It's something I know from experience. And if we were to extend out schedule for a year, we wouldn't finish until 1995. [laughter] We're not even sure the world will be around that long. [laughter] So not just in our line of work, but in the entire grown-up world, everyone's always complaining about there not being enough time.
Summer vacation comes all of a sudden, and it's over all of a sudden, too. But when you're a kid, a month seems like an awfully long time if you're waiting for summer vacation to come. Am I right?
And once it starts, doesn't summer vacation seem awfully short? So then the question eecomes, if we're talking about the same span of time - a month - why do children and adults perceive it so differently?

Well, I think it's because different people and different forms of life sense time and the length of time in very different ways.
If you're a tree that lives five thousand years, a day probably seems to go by in a flash. And then to that tree winter comes, followed by spring; to the tree a single season probably seems like a day does to us.
In the same way, for a bug climbing from here to here - [Miyazaki raises hands a short distance from the desk, indicating height] - represents a huge distance.
For the bug, it's not a small world at all.

And if you think of things this way, the world of plants is also incredibly huge.

Of course, what I'm telling you is all from my imagination, but when we create animation and draw images of living things, we have to study their movements. If you did, I'm sure you would ultimately come to the same conclusion that I have - namely, that a second for a human is an altogether different thing than a second for a plant or an animal.
And if a second is sensed differently, if you think that a dog's been barking for fifteen minutes and it seems like a long time, well, to the dog himself it probably seems like hours. A tree won't tell us itf it feels hurt, but I always think it would be great if we could tell if trees are suffering. My dog made a big fuss this morning, asking me to take him for a walk, but I left home telling him I couldn't because I was busy. [laughter]

These are the sorts of things that you think about when you create animation.


Currently, on Earth in 2019 at least, a grizzly bear lives for 300 months.
It may have to change its size, its metabolism, its adolescence, but if it could live for 1000 months, like humans do...
300/1000 = 0.3 = 30/100 makes bear-time 30% of human-time.
Multiply a sound by that number to translate it timed by the human understanding of what makes a moment

Here’s the patch I used.

Eventually I’d like to embed it here (imagine a way to process audio based on this theory live online, a way for you to quickly test sounds you find online or sounds you’ve gathered at home...)
For the time being the formula above works to find a percentage, and you can always download Audacity (there’s a link somewhere at the bottom of the page I think, a small and free audio workstation!) and use the “percentage change” feature of their speed effect.

I heard once that some monkey calls sound like human laughter when slowed down, though that researcher wasn’t using this lifespan theory.

That might be one to try next…

All recordings on this page were sourced from, the digital collections site for Yellowstone’s natural sound archives at MSU.

Thanks to Jennifer Jerrett for running the collection and contributing many sounds to its holdings. Also thanks to the other recordists and photographers whose information can be found by following the soundcloud links.
Hayao Miyazaki was translated by
Beth Cary.

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