<p>Look closely at a mouse's face and you'll notice fine lines running along its cheeks, almost like tiny stitches. The Alphabet of Ben Sira, a medieval text composed between 700 and 1000 CE, says those marks go back to Noah's Ark - and they're real stitches, sewn by Noah himself.</p>
<p>During the Flood, all the animals lived together on the Ark, crammed into close quarters. One day, a mouse was sitting with its mate near the cat. The cat looked at the mouse, remembered that his father used to eat mice, and figured he had the same right. He lunged.</p>
<p>The mouse ran. There was nowhere to hide on a boat full of animals - no holes, no crevices, no escape. Then a miracle happened. A hole appeared in the wall of the Ark, and the mouse squeezed inside. The cat reached in with his paw but couldn't fit through the opening. So he extended his claws, caught the mouse's cheeks, and tore them open - ripping the skin about half a finger's width below the mouth.</p>
<p>When the cat finally gave up, the wounded mouse crawled out and went straight to Noah. "Righteous man," he begged, "do a righteous act for me. Stitch up the cheeks that my enemy tore." Noah agreed, but he needed thread. He sent the mouse to pull a hair from the sleeping pig's tail. The mouse crept over, plucked the hair, and brought it back. Noah threaded it and stitched the mouse's torn cheeks shut.</p>
<p>And those stitches, Ben Sira says, are still visible on every mouse to this day. It's a charming folk explanation for an animal's physical features - the kind of story that the Alphabet of Ben Sira tells better than almost any other text in Jewish literature.</p>