From Branch to Breath: How Fan Coral and Human Lungs are Alike

A delicate, pink gorgonian (in Dhonfanu Thila, Baa Atoll, Maldives) extends its intricate branches into the deep blue as a shoal of glass fish become blurred silver specks in the background.

Life repeats itself. Not just in the way that days loop endlessly, or history echoes its mistakes, but in patterns. Structures that emerge over and over, as if nature keeps returning to the same design. Look closely, and you’ll see it everywhere. The way rivers split into tributaries like the veins of a leaf; how lightning strikes across the sky as neurons branch in your brain; the concentric rings of a tree stump that make the individual special, nearly identical to the swirls of a human fingerprint. Macro and micro, the universe weaves itself in patterns. 

I wonder, what if this repetition is not just coincidence, but intentional? What if nature speaks in a language of patterns?

Now, take a look at this image. 

What you are looking at is a gorgonian— a fan coral. It branches into the water, looking delicate, like lace against the darkness; but it is strong and sturdy, filtering the ocean, thriving in the quiet rhythm of the current (yet another pattern). If you were to trace its shape, you might feel a strange familiarity. Because, in a way, you’ve seen it before. Inside you.

On land, breath is an afterthought. Silent, automatic, unnoticed. But underwater, breathing is something you can hear. Inhaling in mechanical hisses, and exhaling in a stream of bubbles rushing to the surface. The ocean amplifies it, forces you to notice each breath as if it were something foreign, something fragile. 

A silent exchange takes place in your chest. Air moves through stems, two bronchi that host the filtration of oxygen in your blood and the expulsion of carbon dioxide from it. The sea breathes too, as currents move between the branches of a sea fan, nutrients and oxygen diffusing through its polyps. Two entirely different organisms, shaped by the same necessity. 

A lung outside, a lung inside. 

What I find fascinating about nature is how it doesn’t just stumble upon perfection in its designs; they are refined, repeated and repurposed. This is the heart of biomimicry, the idea that the natural world has already solved problems we are only beginning to understand. The key role of diffusion in coral branches and lungs mirror the use of filtration in medicine and engineering. Perhaps the world isn’t just presenting beauty, but is instead giving us a blueprint to function with. 

So the next time you take a breath, listen. Imagine a fan coral, its branches filtering sea water just as your lungs filter the air. One hidden inside you, one swaying with the current. They are not so different. 

And if life is built on patterns, maybe understanding them brings us closer- not just to nature, but to ourselves.

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Further Reading:

"Biomimicry" by Janine Benyus - https://open.spotify.com/episode/0pNG1RkiKdS0dPqVpdL0IA?si=GU6zOZrrQxGK98urI8W94A

Filtration in medicine: https://psl.eu/en/news/kidneys-water-filtration-example-biomimicry-research-significant-applications 

Filtration in oil and gas extraction: https://biomimicry.net/our-work/natures-ideas-cleaner-oil-gas/ (this article is just to illustrate the role of biomimicry towards cleaner fuel)