curiosity across disciplines

Hidden in plain flight

There’s a concept in physics known as emissivity. It’s about the absorption and radiation of energy from something.

To explain it, imagine a hot summer’s day. It’s 104°F (that’s 40°C for you non-Yanks). The sun is bearing down, with nary a cloud in the sky. A bead of sweat rolls off your forehead onto the ground. You swear it sizzles on impact.

Being a negligent twat, you’re barefoot and you can either choose to stand on regular concrete sidewalk or blacktop. Which do you choose?

The sidewalk, obviously. And so, now you understand something about emissivity.

It can get far more complex, but the scientific gist is that darker colors absorb and emit energy more readily. Birds, especially migratory sea birds, leverage this in some extraordinary ways.

Take the albatross, generally having darker topsides of their wings, with lighter undersides, and often with black tips.

image of a flying albatross

Photo by Nareeta Martin / Unsplash

The darker top wings get hotter, which reduces skin friction drag[1], increasing the air velocity over the top of the wing, and therefore increasing lift.

Researchers also postulate that darker wing tips, like those shown on the albatross above, additionally help increase lift forces by using this color dynamic on the underside of the wing to generate convective currents[2].

All of this amounts to an exceptionally efficient flyer. Albatrosses are so baller that they can spend up to a year without ever setting foot on land; grabbing takeout from the sea and shuteye, literally, on the wing.

Okay, clearly that’s pretty metal. But what can these birds teach us besides the badassery that is giving gravity the middle finger?

That they, and the rest of the natural world, are intrinsically interesting? That elegant designs are everywhere around us, waiting to be seen and appreciated more deeply? That the pale-but-dapper-black-suited, impressive-schnozzed albatross with its unexpected sophistication strangely resembles John Oliver?


But also: humility is an evergreen resource.

Though we’re perpetually uncovering more about ourselves, the environment, and technology, our “time [as modern humans] in the [evolutionary] market” is limited.

Only the hubris of man could think it’s possible to circumvent eons of iterative adaptation by “timing the market,” bending nature to our will via civilization and technology.

And maybe we can, but that’s quite the gamble. “Time in the market” beats “timing the market." So it goes.

Admittedly, our biology, genes, and psychology are the product of the “time in the market” sorts of evolutionary processes. However, our cities, global-interconnectedness, and technologies are but a blip to the millions of years of evolution concentrated into the design of a single albatross.

We should keep doing the things: be curious, research, foster connections, create art, and add to our collective compounding project that is humanity.

But we should also leave space for appreciating the beauty in what we don’t know.

  1. Hassanalian, M., G. Throneberry, M. Ali, S. Ben Ayed, and A. Abdelkefi. “Role of Wing Color and Seasonal Changes in Ambient Temperature and Solar Irradiation on Predicted Flight Efficiency of the Albatross.” Journal of Thermal Biology 71 (January 2018): 112–22. https://doi.org/10.1016/j.jtherbio.2017.11.002. ↩︎

  2. Rogalla, Svana, Liliana D’Alba, Ann Verdoodt, and Matthew D. Shawkey. “Hot Wings: Thermal Impacts of Wing Coloration on Surface Temperature during Bird Flight.” Journal of The Royal Society Interface 16, no. 156 (July 24, 2019): 20190032. https://doi.org/10.1098/rsif.2019.0032. [3] ↩︎

  3. Also, look at this citation above! “Hot wings”?! Scientists know how to have a good time. ↩︎