Why are some feathers blue? (2012)

smithsonianmag.com

19 points·jcl··11 comments

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> like a sponge or a box of spaghetti

In what way is a sponge like a box of spaghetti?

Lots of air pockets?

"interspersed with air pockets, like a sponge or a box of spaghetti."

Is a box of spaghetti more interspersed with air pockets than a box of just about anything else?

No, and no one said it was. It was just one out of many possible examples of something with a lot of air pockets.

What type of pasta would be more appropriate for the analogy? Clearly, spaghetti is probably the worst... I suggest macherroni (i.e. the mac and cheese noodle) or, perhaps, cavatappi.

I think it is a good example because it is fundamentally different than a sponge. Spaghetti have air pockets moving in just one dimension, in a linear fashion, and of the same size; whereas a sponge has multisize 3d air pockets.

Maybe it's the uniform pattern of the air pockets?

>scientists theorized that birds look blue for the same reason the sky looks blue: Red and yellow wavelengths pass through the atmosphere, but shorter blue wavelengths bounce off of particles and scatter, emitting a blue glow in every direction.

As XKCD has pointed out, there's a complicated physics reason behind every substance's color and the atmosphere isn't special or unusual in that regard. The sky is blue because air is blue.

Right, as I was reading this I was thinking "Isn't that just describing the way light and color normally works?" We haven't really answered the question "why is the sky blue," more like, "how does the sky get its blue color?"

Cool idea. The site is infuriating though. Auto play video bullshit.

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