In 1638 Galileo Galilei, who is called the Father of Science, published the Square-Cube Law. Frankly, it’s not particularly clever as scientific discoveries go. It’s an observation that big things are bigger than small things. However, the particular way in which objects scale does create a few interesting implications.
I’m going to explain the concept using Jell-o. Alright, so imagine a perfect cube of that fruity lime-flavoured gelatin dessert sitting on a plate. Let’s say the cube is 1 inch in all directions. But, seeing as how there’s always room for Jell-o, you say you want “twice as much”. So, you would be expecting a cube that is two inches tall. Twice as much, right?
Not so! It may be twice as tall, and twice as wide, but the other measurements of size have more than doubled. The surface area has been squared, and the volume has been cubed. (hence Square-Cube Law) So, going by the volume, you actually have eight times more Jell-o in a 2-inch-sized serving as you do in a 1-inch-sized serving. A serving 4 inches across would contain 64 times as much Jell-o!
This exponential growth puts a hard limit on how big your Jell-o serving can get before it overwhelms the structural integrity of gelatin. As the volume increases, so does the weight of all that Jell-o pushing down on the bottom-most layer. (the mass is growing faster than the footprint, so the pressure increases) If you visualize this growing cube on your dinner table, you can picture it begin to bulge and eventually crush itself into a gooey mess.
This same law puts a limit on the size of land animals. It explains why ants can walk around on spindly little legs while lifting 50 times their body weight, compared to elephants with their tree-trunk sized feet who would strain to lift a quarter of their mass.
It also affects more than the size of animals. Elephants are practically naked (compared to most other fuzzy-haired mammals) because they have significantly more inside (volume) relative to their outside (surface area) and have a much harder time cooling down their body temperatures. Maximizing the surface area for cooling also explains the big floppy ears and wrinkly skin, which can expel more heat than a smooth surface.
It also explains why the Nazis failed when trying to build a massive tank, and why our giant friend Robert Wadlow needed leg braces to walk. Oh, and why an elephant might die if it could only jump, while a mouse could safely fall off a building. And lastly, if not to beat a dead horse, it explains why Goliath probably wasn’t ten feet tall.
- Source: Galileo’s Square-Cube Law – DinosaurTheory.com – which is just the introduction to the rather curious problem that huge dinosaurs seem to contradict the law. I’m not done reading the whole theory on that website, but so far it’s quite interesting!