Is the Drinking Bird Alive?

On Dissipation Structures

Once upon a time, the World Honored One was walking with gods and devas and humans, when he paused. He pointed to the ground and said, “This is a suitable site to build a temple.” The god Indra then plucked a blade of grass from nearby and stuck it into the ground at the spot where the Buddha had pointed. Indra declared, “The temple is built!” The World Honored One smiled. — From The Book of Serenity, compiled by Hongzhi Zhengjue, twelfth century AD.

This drinking bird has been with us for five years now. It has followed the family through two house moves, and it still does its drinking duties nicely. It is part of the word experience of my grandchildren, who never fail to cheer when the little beastie dips its beak into the glass of water.

A toy, yes, but also a fascinating thing. My plan was to use it as a tool to illustrate some features of thermodynamics to my students at the University of Florence. But the bird was unfortunate to arrive during COVID times, and classes went online, and when they didn’t, they became dull and uninteresting anyway. In any case, in the few attempts I made, I noted that my students were normally unable to explain the mechanism that made the bird drink.

It is not complicated; the bird is nothing more than a thermal engine that exploits a small temperature difference. So small that its theoretical Carnot efficiency has been estimated as a little more than 1%. The efficiency of a real drinking bird is much smaller than that. For sure, you cannot use it to power the kitchen’s refrigerator!

But the fascination with the bird is the way it mimics real life. And it does that all by itself; the little thing looks alive. And, indeed, it is an illustration of one basic feature of the universe: that of the “dissipation structures,” the term coined by Ilya Prigogine. He was a Russian physical chemist who received the Nobel Prize for Chemistry in 1977. The bird dissipates the energy potential of the small difference in temperature created when water evaporates on its beak. It really “drinks” water. Note how the two glasses initially were at the same level. The bird has dissipated more water vapor than the glass without the bird. And so, yes, the bird is alive in a certain way.

The point of the story is that we often tend to think of thermodynamics as limited to closed systems. We speak of the “heat death” of the universe, and we believe entropy really increases all the time. It is true in closed systems, but the real universe is something completely different. It is dominated by complex, dissipative structures — and not necessarily biological ones. Stars, tornadoes, hurricanes, lava lamps, and drinking birds are all examples. And people, too, are dissipative structures.

The point of dissipative structures is that they can evolve. Not every structure can — the little drinking bird cannot. But evolution is the key feature of the universe. Everything that can evolve, evolves. It evolves in a Darwinian way, not by competition, but by adaptation. And everything follows this pattern as the universe moves on. Maybe even the universe we know is the result of the evolution of multiple universes. And we don’t know how this evolution will take us. The universe is fractal, and a blade of grass and a drinking bird reflect its complexity at all scales. William Blake had understood the point when he wrote his famous poem in 1863:

To see a world in a grain of sand
And a heaven in a wild flower,
Hold infinity in the palm of your hand
And eternity in an hour.