<p>Does anyone know? I think its so funny, I will scratch dogs’ bellies all day just to see that.</p>
<p>To give you more access to their entire lower body…they lack inhibitions…they just want a full-body rub!</p>
<p>Maybe the dog’s thinking “why does joev scratch my belly when I move my hind leg?”</p>
<p>Why? Because they can.</p>
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<p>I think that’s the answer to a different question…</p>
<p>It’s called the Scratch Reflex:</p>
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It’s really an itch but I think of it as something fun, like tickling. Hopefully dogs like it, too.</p>
<p>Here’s a link to a longer, more detailed answer from Google: <a href=“Google Answers: Dog Leg Shaking”>Google Answers: Dog Leg Shaking;
<p>CC is so educational, don’tcha think?
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