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Name: Victoria
Status: student
Age: 12
Location: N/A
Country: N/A
Date: 1999-2001

Why are so many natural or man made things curvilinear - How come I don't see many straight edges in nature?


This is a very good question, and I do not think I can do justice to it in a short reply and without thinking more about it. I share with you some ideas here.

First, the straight line is a very specific kind of a line and I do not think that it is particularly over- or under-represented in nature. In fact, if many of the "natural" lines were straight, we would then wonder why? Secondly, we need to ask what we mean by a straight line. I assume you are referring to "visually" straight lines. In that case, your perception and perspective are also important. The trunk of a tree may look straight to us at a distance but can be quite irregular as you look closer.

A more general and physical explanation for the shape and patterns in natural (and man-made) things could be given as follows. The physical, structural, and functional attributes of natural things have evolved over time, over millions and billions of years, as a consequence of their interactions with their natural environment. The outcome of these interactions, in most instances, is anything but random. There are laws governing these interactions. So, not only the shapes but also the properties and functions are determined by the governing laws. So, to ask why something has a peculiar shape or function is asking, "what relevant laws govern its creation, evolution, and function?" Laws of nature are peculiar and often elegant. We can discover them but we have no clue why they are there. We can find "what and how" they are and not "why" they are. Underlying many of these laws are others, such as the conservation laws. These, to me at least, seem to be nature's clever way of managing itself.

In summary, we can say that things have the shapes they have because their existence and evolution, by necessity, follow certain laws that dictates those preferred shapes. But we do not know why those laws are the way they are.

For example: Why are tree leaves mostly green? Why is the sky blue? Why are the pebbles on the shore round? Why is raindrop round and not square? Why are soap bubbles round and not cubic? And so on.

The answer to these are, respectively, chlorophyll, light scattering, wear by collision and water action, and surface tension (for the last two.) I am pointing to the governing laws to explain the shapes. But in the final analysis, I can say how they are but not why. The "why" question, I think, is not one that science can answer at this time. It is more of a philosophical and theological question and beyond my knowledge.

Good luck,

Dr. Ali Khounsary
Advanced Photon Source
Argonne National Laboratory

Because there are a zillion ways to be crooked but only one way to be straight. Nature tries everything, so if you take random samples of things Nature has tried, you get a straight line once every zillion samples. And you don't see precisely the same crookedness any more frequently than you see straight lines.

However, if you look closely at crystals of pure substances (or of precisely the right mixtures of the right different substances), you'll see lots of straight edges. Nature's not all that big on pure substances, though, because there are a zillion ways to be mixed...

Tim Mooney

Nature does have a lot of straight lines especially when discussing light direction and crystalline faces. Slate is a rock that has straight lines due to its crystalline structure. However, most living things are made up of organic compounds that are polar (unsymmetrical if you like) in nature and do not form "straight lines" in their compound bondings. If Nature was inorganic (bonding in patterns to a degree), we'd probably see more "straight lines".

A chemist would complain like crazy to my above explanation!! I have over simplified it all a bit!

Furthermore, organization takes energy and forming straight lines would be organization to a degree. Man makes straight lines out of nature, but it takes energy to do so. Nature is just plain lazy!

Steve Sample

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