Back Leg Bounce

Bugs’s hind legs inspire me.  I find them beautiful, awesome.  Share the joy.

 

 

 

 

 

 

 

 

Kim and I were wondering whether these hind legs could have inspired the design for automobile struts?  I found no answer to that question.  The bendy bit, in this picture, is what we were thinking about:

It’s amazing how much power Bugs’s back legs can generate.  When he and I were refugees in the pet-friendly motel, you may recall he found a tiny aperture behind the bed in which to wedge himself.  He hid like that when we first arrived and it took hours for him to come out.  He hid again when a knock on the door scared him.

I had piled up a mountain of pillows and bedspread at the mouth of the aperture, to try to prevent him from re-wedging himself.  I even jumped on the mountain with both feet, to pack it down.  At the knock on the door, though, Bugs fled back to the aperture.  He shoved his head under the mountain.  He dug his claws into the rug behind him.  He beat a rhythmical, furious tattoo with his back legs.  His head turned into the tip of a mining drill.  His horrible gray backside followed, inch by inch.  And then poof.  Gone again, for another couple of hours.

Later, as he began to work his way out, I did take the opportunity to spy on him thanks to the invaluable flashlight.  I was treated to Bugs’s horrible gray backside bouncing up and down – the aperture was too narrow to allow any sideways movement.  He inched out butt-first, of course, he could only go one way.  The spectacle will live in memory.

Those back legs bend.  They look as flexible as bamboo.  Here’s what bamboo did in our last ice storm:

Bamboo as it normally stands up, without ten tons of ice pressing it down.

Bamboo with ten tons of ice pressing it down.

Bamboo bounces back (for the most part)

I pictured Bugs jumping like bamboo in slow motion.

I wondered whether there could be any anatomical parallel between Bugs’s back legs and those of kangaroo rats –

 

 

— or jerboa —

— or rabbits —

I could find no answer.  Technical language like this defeated me:

“Small perturbations applied during the swing phase altered the movement of the contralateral leg in a manner that tended to maintain alternating stepping when the ankle force signal was included but tended to shift coordination away from alternating when the hip position signal was used alone.”

“Computer Simulation of Stepping in the Hind Legs of the Cat: An Examination of Mechanisms Regulating the Stance-to-Swing Transition,” Orjan Ekeberg and Keir Pearson, J. Neurophysiol. 94: 4256-68 (July 2005).
http://jn.physiology.org/content/94/6/4256.full

The diagrams from that article sure are pretty, though:

 

You may recall that Bugs and I had fled to the pet-friendly motel in the first place because trees were being cut from under the electrical lines.

https://catself.wordpress.com/2011/02/01/refugees-of-december-%E2%80%9910/
https://catself.wordpress.com/2011/02/04/it%E2%80%99s-all-relative/

Here’s what the tree-cutting ended up looking like:

It’s unlovely, true.  But when you consider the trees that were at risk, we are incredibly grateful that the big ones were spared.

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