What an odd question. Also, what does it have to do with fiction? For me, at least, it’s important for world building. Right now, I’m creating a huge and detailed world, probably to set stories in later (I posted a map of one tiny section of it before). When making up completely new creatures, it is possible to change things that we think of as fundamental, like having limbs, or a central brain, or only existing in the physical world. Anything we can conceive of, we can create in a fictional world.
For instance, in my world there are intelligent creatures several inches high and other 350 feet high. I don’t have to explain how that’s possible, since it’s just fiction, but that got me thinking: why are we the size we are? Could we be just like we are now, except the size of ants, or the size of mountains? Here are my thoughts on the subject.
Why it would be harder to be bigger
Being a little bigger is not that hard. Elephants are pretty big, although compared to the tallest living thing on earth, a 380-foot redwood, they’re tiny. Trees have it easier though, since they have a rigid cell structure, they go straight up, and they don’t move. But could we ever be that tall? One problem is the weight. We would need to have incredibly strong bones to hold ourselves up if we weighed 100 tons or so. A couple ways around this would be to be mostly gaseous, like balloon people, to live on a smaller planet with less gravity or have bodies built of some insanely strong material, like titanium-alloy lattice or something.
Another problem with being very large is the time it would takes nerve signals to travel to the extremities. From what I have found (correct me if I’m wrong), nerve impulses travel about 100 meters, or 330 feet per second. So, if we were 350 feet tall and stepped on a nail, it would take a whole second for us to realize it. That’s kind of hard thing to live with, always being one step behind the rest of your body. This could be overcome possibly by having some other way of sending nerve impulses or to have a diffused brain, or even several brains that could handle various parts of the body. In any case, we would have to be radically different in design if we were going to be super huge.
Why it would be harder to be smaller
Well, how about being smaller? Could we be the size of ants and still be just as intelligent as we are now? The problem with being smaller is that we would have smaller brains. Perhaps if our brains worked differently, they could be much smaller, but as things are now, there is a reason why we are so much smarter than insects.
Another issues about getting very small is the loss of resolution. It’s like if you zoom in on a picture; at some point it will start to pixelate, because as the size of the whole picture gets closer to the size of the pixels, it is harder to show detail.
In the picture above, the number of pixels is huge, so even after zooming in three times, you can only just begin to see them. For living things, the things we are made of–atoms–are insanely small, so we would have to be pretty small before we started to lose complexity, but the point is, that we could not be just any size and still be intelligent human beings. Look at what a car looks like when it’s made of individual atoms, compared to a real car.

The molecular car image courtesy of Wired.
Yeah, there’s no comparison, in terms of complexity. In the same way, we could not be very tiny and still be us. At what size that loss of complexity would start, I’m not sure. If you have any idea, let me know.
So…that’s what I think about all day. I’m not an expert on this sort of thing; I just like to think about it. If you have any thoughts, please share them in the comments.
February 13th, 2013 at 1:11 am
David, If this is what travel does to you as a writer…..Awesome! 🙂
February 13th, 2013 at 4:42 pm
I would rather be big than small, if I had a choice. Ike the idea of giant gaseous beings floating around in the air. Still on your trip? How’s it going?
February 13th, 2013 at 6:14 pm
Actually, I came back early, but I’ll be totally gone all of next week. I might schedule a few posts for that time. The first part was good, hopefully the second part will be good too.
February 13th, 2013 at 6:48 pm
One whole second? In a hundred metre dash – think of the number of nails before we go ouch! – there goes my Olympic Gold 😦
February 13th, 2013 at 6:55 pm
At least if you were that tall, you could do the 100 metre dash in one stride. 🙂 A second doesn’t seem like much until you think about holding your hand on the stove for that long before realizing it.
February 13th, 2013 at 8:12 pm
Well, I’ve already run into some pretty gaseous normal-sized human beings; they’re usually seated next to me on airplanes…
I hadn’t thought about the pixelation of tiny humans — that’s pretty interesting. Could we interact with one another if we were “blurry”?
If we’re voting, I choose Titanium Alloy Giants.
February 13th, 2013 at 8:18 pm
Being titanium alloy giants would sure make football pretty interesting. 🙂
February 14th, 2013 at 12:22 pm
Great article, although I’m sorry but I just have to ask – where did you find the picture of the giant and the little town? I have to admit that although i was searching for Nanotechnology blogs, what made me click on yours was that picture!
February 14th, 2013 at 2:12 pm
I’m glad you liked it. I got the picture from a Google Image search. Here’s the image link: http://images4.alphacoders.com/235/235138.jpg
February 14th, 2013 at 11:07 pm
Thanks a lot for responding! I took a bit more time today to look over your blog – good job! I know just the person that would like it, so I’ll share the link with them 🙂
February 14th, 2013 at 11:08 pm
No problem. 🙂
February 16th, 2013 at 4:07 pm
mind boggling question if you look hard for its answer!