Wednesday, February 08, 2017

It is Like a Sponge or a Box of Spaghetti

Today is the second day with temperatures in the warm 60s F.  In and off itself not a fact of global warming, but another chain in the link of a very mild winter which is another factual example (along with that YUGE breakin the ice shelf up North that is now 17 miles long.)  Yet this post is not about climate change.

I put out some bird feed in my bare feet on such a warm morning and then stood still for a minute or two and heard the song of the bluebirds just at the edge of the woods. Amazing. Singing! I am hoping they are not getting in the mating mood as we have many weeks of cold weather ahead. We are actually supposed to get snow tonight! 


Anyway, this got me thinking about bluebirds in specific and in general. Birds with yellow or red feathers get their pigment from food they eat.  Do bluebirds do the same?  Your first thought is blueberries, right?   But the science community says the blue color in blueberries is destroyed in the digestion process so the answer is "no".


So I did some reading.  I found the answer and while the reason is a bit complicated, my readers are intellectuals and love this stuff so I will share. Birds that have blue feathers in part or whole have changes in that colored feather itself as it grows. Inside each feather cell is stringy keratin molecules that separate from the water in the cell, something akin to oil and water. "When the cell dies, the water dries away and is replaced by air, leaving a structure of keratin protein interspersed with air pockets like a sponge or a box of spaghetti. When white light strikes the blue feather, the keratin pattern causes red and yellow wavelengths to cancel each other out, while blue wavelengths of the light reinforce and amplify"...and return to your eye as blue.



Difference in shapes and sizes of the air pockets mean different shades of blue. Therefore the color is not a pigment in the feather itself but a light reflection.

Why have the birds evolved this way?  Scientists don't really know but they theorize the bluest blue represents health to the female or perhaps just plain beauty.  OK.  You did not waste your time here today. You learned something new unless you already knew.


13 comments:

Bob Bushell said...

Wow, those are beautiful images, especially the Bluebirds, and the one at last, absolutely stunnings.

Studio Maywyn said...

Lovely photos
Thank you. I didn't know.
I think maybe the blue sky plays a part in the blue jay's evolution, survival thing. Then I think, wait a minute, they nest in pine trees that are dark green. Oh so maybe, blue to fly and not be nabbed, and blue for nesting so the mates can easily find each other. Cool.

Jenny Woolf said...

They are pretty little birds. I have never understood why some birds blend in with the background and others stand out - but I suppose it makes sense if birds have a variety of different survival strategies, and don't all have the same ones.

messymimi said...

Yes, i did learn something, and i thank you.

Marie Smith said...

Our feathered friends provide great science lessons, Tabor!

Red said...

I learned something new and it was interesting. Blue birds start to nest here at the end of march. they are some of the earliest nesters.

The Furry Gnome said...

Fascinating! I did learn something new. Are those really10 Bluebirds round a birdbath.

Linda Reeder said...

Oh, those little bluebirds are so cute!
And science stuff is always cool.

Snaggle Tooth said...

A different way to think about color n light. Like when I looked up Why is the sky blue? Also looked about dragonfly colors n found out differences between them n damsel flies, n a similar thing about those metallic blue colors, it is light n not pigment on them. Our eyes don't know it tho!

Always like your bluebirds!

Marcie said...

I learned that about blue feathers just a few months ago with the children I tutor. I love all the nature science that is part of their curriculum, and as a nature lover myself, I expand on it. Amazing how much there still is to learn, after all these years, about this beautiful world! Your photos are fantastic, by the way!

joared said...

Fascinating, as blue is my favorite color -- all shades -- and I never thought about why birds feathers blue. Bluebirds are favorites from when I lived in Great Lakes area, but we have none here in Southern California. My recently deceased friend used to entertain me with accounts of them visiting her east coast home or viewing them when she able to take a walk in the woods behind her home.

joared said...

Fascinating, as blue is my favorite color -- all shades -- and I never thought about why birds feathers blue. Bluebirds are favorites from when I lived in Great Lakes area, but we have none here in Southern California. My recently deceased friend used to entertain me with accounts of them visiting her east coast home or viewing them when she able to take a walk in the woods behind her home.

ellen abbott said...

well, that was interesting. I knew there were bluebirds around here but I had never seen any until last spring when I put a birdhouse I had bought for $5 on a low wall over at the shop. I put it there mainly for decoration because I thought the hole was too large to keep predators out and no bird would nest in it. To my surprise, a pair of bluebirds did and raised three chicks.