Structure of a Spider Web

It is a well known biomimicry meme that ounce for ounce, spider silk is stronger than steel or Kevlar.  But what is it about the structure of a spider silk that makes it so strong?   Is it the nano scale makeup of the silk?  Is it the pattern?  Do the patterns indicate function?  Over the summer, I've collected a couple images of spider webs as I've seen them and tried to learn a little more about what makes them so special and how we can learn from them.

Spiral orb web in the forest

I started by taking a walk in the forest preserve near my house. Quite quickly I came upon the most ratty looking, massive spider web I'd ever seen.  It looked like something out of a haunted house movie - spiral, torn, and at the center was a huge spider.  As soon as I walked through the brush to get a closer look, the spider took off thinking it should be afraid of me (the feeling was mutual).


It's about Scale

The first thing I learned about spider web construction is that it is modular based on the size of the spider - the larger the spider, the larger the gaps between the threads for the simple fact that the spider must walk on it without getting stuck in its own web.  In fact, the scale of the space between the sticky threads that catch prey is directly proportional to the space from the tip of its back leg to its spinner.

This makes me think of the whole idea of "human scale" in architecture, which of course varies.  Frank Lloyd Wright designed homes for men of smaller stature, such as himself, so that when a taller person such as me walks through a home he designed, I feel like a giant.  The difference is mere inches, but it is noticeable.  Cathedrals were designed in direction opposition to the idea of human scale - they were designed to overwhelm the humans that entered them in order to convey the greatness of their god.  But the spaces where we feel most comfortable are the ones that have been designed down to the detail with our proportions in mind.

Life in and Around a Tree

We sometimes think of trees as solitary objects - lone specimens standing in a field of green.  Or we think of them in clusters of a forest, one indistinguishable from another.  But trees, like everything else, are interconnected and linked with all life around them.  I thought about this when looking at the tree in my backyard yesterday.  What life does this tree support along its vertical axis?  And what relationships do these life forms have with each other?  What can we learn from these connections?

The pride of my backyard - our Norway Maple

Our Norway Maple was planted well over 50 years ago, and is large and established, much like most of the trees in my downtown neighborhood.  This type of tree, however, is considered to be an invasive species because it sends off thousands of little "helicopter" seeds, sometimes a couple times in a season, that create tiny little trees everywhere you look.  Its leaves are also so complete as to shade everything below it and its roots are so dense and shallow such that very little else can grow among them. For these reasons, and the fact that it was planted underneath an elevated power line, I'm not sure it was the best selection that the former land owners could have made, but I love it just the same.  

I love that my house was designed on axis with the tree so that as soon as you walk in my front door, you see the tree centered in the back.  I love that it shades the back part of my yard so completely that you can lie in the grass in 90 degree weather and feel cool.  I love that my daughter's playhouse never sees the sun and is always cool for her to play in.  And I love all the critters it attracts to my garden - even the chipmunks which eat every last strawberry I plant.  Well, maybe not the chipmunks.  What other life does my maple support? 

Let's look a little closer.

Studying a Flower - the Plumeless Thistle

Here is the problem with a novice naturalist walking through a restored prairie and seeing pretty flowers - I assume they all should be there!  It turns out that the pretty pinkish purple flowers I saw on a walk I did way back in July (how summer flew by!) were actually Plumeless Thistle, an invasive weed, and it was everywhere, at least near the walking path I was on.

One invasive species on another - a Japanese beetle on a Plumeless Thistle bud.  From Prairie Flowers in July.

While walking through the prairie on bright July day, I wanted to observe the prairie species mix to see if I would find any patterns.  The main pattern I found was centered around water availability.  The highlands where there was no standing water found home for yellow coneflower, wild carrot, thistle, some milkweed, and turf grass gone to seed.  The lower areas where the creek ran through hosted cattails, grass, a spiky purple plant that looks like salvia, and some strange broadleaf species that seemed like it would be more at home on the forest floor.  Near the paths in higher elevations, I was taken by a pretty purple flower that I found and thought I could learn a little more about it.

Studying the thistle, by Amy.

Local Biomimicry

As a part of my coursework on Biomimicry's Life's Principle to "Be Locally Attuned and Responsive," I wrote an informal white paper on the intersection of Biomimicry and the Transition Town network using my town of Naperville, Illinois, as a case study.  I posed the question,

"What would Naperville look like if it followed the biomimicry principle to be ‘locally attuned and responsive’ in all of its (re)designs?"  

This fits in with our theme for the year at Greendrinks Naperville of local resilience in the face of peak oil and was written to further this discussion.  If you have time to spare and care to read and comment, I would love to hear your thoughts.  Read my paper "Local Biomimicry" here.