It's been interesting to observe the mice I raise to feed our pet corn snakes (now numbering 4, all caught around our house). I wonder if these domestic white mice are as different from their wild relations as our laying hens are from their wild counterparts. If all the generations of selective breeding in white mice, probably favoring fecundity, has changed the way they carry their unborn, and the number of pups they will bear at one time. When I see my mouse mamas before delivery I wonder how they would ever manage in the wild in that shape. They look like Jerry the Mouse in the cartoons when he's swallowed a light bulb and changes into that shape. Their sides get so swollen and you can see the pups wiggling around under their fur. And they can bear a dozen pups easily, sometimes more. I guess they carry out to the sides rather than out in front of their abdomens, otherwise their feet wouldn't touch the ground. Do wild mice get like this when they're pregnant? Do they swell out so far? Or do they retain a slimmer profile and bear smaller litters? I wonder if the white mice, being raised in safe confinement, can now afford to grow bigger. And if breeders have favored the mouse Mamas who can bear the bigger litters, even if it makes them so bulgy, bulky and slow. Sometimes I think I'll hear a big kaboom! and find dozens of pinkies flying all over the patio coming from an exploded, exhausted Mama mouse.