Animal Drawings from a Sculptor's Perspective

Animal drawings, like we have never showcased before.
We have shown animal studies, or. animals wrapped in text and notes. but never like this.  When I firs saw Ran Shapira's work, I was puzzled.  Then I noticed that he is a sculptor and it started to make sense for me.  There is no explanation on the site, so this was just my guess: as a sculpture you can either eyeball or measure, to get the proportions right and this is what might have been going on here.  Then I noticed that each of his drawings has x=42, not a clue? Me neither, so I looked it up on Google and this is what I found:
"X-42 is the designation of a still-classified U.S. military space project." 
None the wiser but a twice as intrigued, I leave you with the drawings...

Mountain Gorilla.
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Giraffe.
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Rhino.
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Wild Boar.
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Zebra.
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Kudu.
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Lion.
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Elephant.
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Water Buffalo.
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Gazelle.
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Nyala.
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Hyena.
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