And now for something completely different, a little chicken anatomy and physiology
Chickens have a third eye lid a nictitating membrane it moves sideways across the eye, from the inner corner of the eye to the outer; here is one of the white leghorns taking a drink from the pond,
I’ve unintentionally pressed the shutter when the membrane was across her eye, she normally looks a bit brighter eyed than this; we humans have a vestige of the membrane still remaining in the inner corner of our eyes, isn’t evolution clever.
some birds fly with the membrane closed, it’s thought that it helps protect the eye from dust and grit, its transparent so they don’t crash, sort of Biggles goggles for birds
The lower eye lid of the chicken is more mobile than the upper, they ‘blink’ with the membrane, closing the eyelids ‘proper’ for sleeping, this is Thing One basking in the sun.
Birds have developed a flock of adaptations to suit their needs Woodpeckers tighten their nictitating membrane a millisecond prior to their beak impacting the trunk of a tree in order to prevent their eyes from leaving their sockets
I think that is so cool,Tom thinks it is ‘mint,’ as I imagine, does the woodpecker.
That first photo is way cool! And I am educated at that! I hadn’t known about the third eyelid.
Its a bit like the fact we can’t sneeze without closing our eyes as the pressure exerted could pop our eyeballs from the skull!
Cool!! And how many times have I tried it? Even though I know it would be messy and painful? LOTS! Never works though………….. unconscoius brain safety techniques trumps curiosity everytime!
What amazing photographs, Thing1’s lower eyelid is just a tad scary. The woodpecker that took to demolishing my deck handrail this spring must have had heavy duty membranes. No bird, even one over a foot tall, should be able to make the windows shake and rattle in their frames. He was hammering the nails in the handrail as the house echoed and amplified his territorial warning, lovely just not at 5am!
Um, Bard, I hate to tell you this but it’s altogether possible that you have carpenter ants in the deck rail. You might want to investigate . . .
‘Gerry Sell, Global pest and vermin control specialist’, rather a snappy title
Fascinating stuff! I really like your clever description, “…sort of Biggles goggles for birds.” Thanks for the lesson.
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