What if Your Guinea Pig Grew Up to Be Larger Than Your Refrigerator?

What if you went down to the pet shelter and picked up a cute little guinea pig pup and brought it home to live with you? And what if, as it began to grow, it began eating unusually large quantities of grass and hay and drinking enormous amounts of water – much more than its little guinea pig brothers and sisters? After a few days, you begin to notice that the floor of the cage is beginning to sag a little – but still the pudgy little pig continues to eat.


And as the weeks go on, your cute “little” guinea pig eventually outgrows its cage and you are forced to build a little corral to house it in another room. By now, it’s about the size of a real pig – a potbellied pig. But still it continues to eat. And it continues to grow. It has now become virtually impossible to pick up the “little” guy and put him on your lap to pet him anymore.

By the time it’s done growing, it is the size of a mid-size sedan. And still it continues to eat. Of course, now that it’s more than 1400 times as large as the other cavies in your house, you’ve moved it outside. The floor in your house is no longer able to support its weight – it now weighs in at over 1500 lbs (not to mention the smell).

No doubt about it: if you had such a pig, at more than nine-feet long, it would definitely be the biggest cavy in the neighborhood. But is it conceivable that you could you get actually get a pet like this? Surprisingly you could – but only if you could build a time machine.

Phoberomys pattersoni was such an animal – a 1500 lb. guinea pig (actually an early relative of our modern guinea pig that lived in northwestern Venezuela eight million years ago). Scientists speculate that the large rodent eventually became extinct because it was not able to escape its natural predators as easily as swifter, hoofed animals such as antelopes and gazelles. And it was unable to scurry away and hide from predators as do smaller rodents. It’s a good thing that it did become extinct because we certainly couldn’t afford to buy a cage for it.