x did evolve from y.
The lower right leg developed to enable the x to stand better, giving it a survival benefit over the top-heavy y.
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2 Can Chunder Word to your mums, I came to prod bums,
Sun 9 Oct 2011, 19:01,
archived)
or perhaps the y from x
it lost a leg enabling it to lie down more comfortably. maybe. who knows. one can only guess.
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artifus is doing it all wrong,
Sun 9 Oct 2011, 19:09,
archived)
All the cut absorbed by had it been a dog
Just mixing it up a bit there
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Photoshop Bitch 2014 edition,
Sun 9 Oct 2011, 19:40,
archived)