July & August 2006
The world around us
by Don Welty
As spring passes on, the long, warm summer days we’ve all been looking forward to finally show up. June arrives with all its beautiful wildflowers and songbirds. Another big change is the rapid increase in the insect population, many of which we would choose to do without.
However, we do have help. Junco’s, sparrows, fly catchers, and swallows all delight us as they consume large quantities of flying and crawling, biting and stinging insects.
There is another predator of these insects that is much more abundant and consumes many times more insects than all the birdlife combined. It goes about its business quietly and efficiently, eliminating countless numbers of insects, 24/7 all summer. With a job description like that you would think that we would be artificially breeding and releasing them and making homes for them. Although rarely noticed, when they are seen, they are often squished, squashed or flung into oblivion. This small, eight-legged arachnid, the spider, is one of our most unappreciated neighbors.
Spiders are the king of adaptability, found in nearly every corner of the earth. Found in caves, deserts, underwater, homes, on glaciers, alpines, rainforests, it’s hard to find a spot they haven’t found first. Although most live entirely on insects, some species feed on plant material.
While hiking out on the enormous Bagley Ice Field, we once came across a gravel moraine covered with small brown spiders. We had landed on the ice, several miles from the nearest mountainside and even further from the closest bush. How those spiders got there and what they were feeding on is still somewhat of a mystery to me.
Spiders have many marvelous attributes but are best known for their mastery of spinning silk. Spider silk is produced from six small fingerlike organs attached to the rear of the abdomen, called spinnerettes. In the tip of the spinnerette is the spinning field, covered by as many as one hundred spinning tubes. The fluid silk hardens rapidly as it comes into contact with the air. Up to five different types of spinning fluid can be manufactured by the same spider, skillfully mixed different ways, to use for different purposes. Another gland is also used to produce the sticky capture glue, used on the web to entrap their prey.
Different combinations of fluid strands are spun together to serve different purposes. One type is used to make a protective egg sack for the young. Another type is spun in sheets used to wrap up prey after capture. Spiders also produce a dra-gline that they use to catch themselves in a fall, or to drop for a speedy retreat. Some strands are spun with multiple strands parallel for strength without stretch, like a cable. Others are spun with a spiraling sheath that gives strength and impressive elasticity, with up to 200% stretch. Dragline silk, used as the main support for the web, is estimated as 100 times stronger than steel and even much stronger than KEVLAR®. It has been estimated that a cable of this silk slightly larger in diameter than a garden hose could support the weight of two full-loaded 747 aircraft. Spiders can also speed up the manufacture of silk 10 times allowing it to drop rapidly for a quick escape. Another type of silk is used to catch the wind allowing the spider to lift off and travel in the air currents to far off places. I have seen these thousands of feet in the air while flying and wondered what they were.
So, if this silk is such a miracle fiber why don’t we make it? We’ve tried. Some researchers have tried to make silk by forcing silk proteins through minute holes, but the fibers are less than half as strong than those produced by the spider. This is because the spider makes the proteins go through a “liquid crystal phase” to align their rod-shaped molecules, similar to the KEVLAR® manufacturing process. This process allows the silk to flow more easily and allows formation of the spiraling fibers. A technical description of this process can be found in Nature magazine 410 (6828):541-548, 29 March 2001.
I could go much further in demonstrating how vastly superior this small “ancient” design is to anything in today’s science and technology. A robotics expert would be recognized and praised worldwide if he could make a multiple jointed eight-legged robot. A robot capable of responding to all imaginable situations of terrain, danger avoidance, sensory and response coordination, self-repair or self-fueling from insects. And those would be the easy ones. How about being able to produce hundreds of exact copies capable of doing exactly the same things on its own! Nature magazine spends 6 pages on the complexity of just silk! They also give the usual homage to evolution as the designer without the slightest evidence.
The fossils show evidence of spinnerettes in specimens supposed to be 400 million years old. Do we find increasing complexity occurring? Natural selection leads to a loss of genetic information. Mutations always lose or re-arrange existing genetic information.
I encourage you to investigate in detail any facet of this awesome creation around us. It speaks for itself. I hope that with diligent investigation and a discerning spirit you will join me in praising our awesome Father in Heaven for this amazing world around us.
“Wisdom calls aloud outside; she raises her voice in the open places.” Proverbs 1:20
References:
1) Fox, D., The Spinners, “New Scientist,” 162 (2183):38-41, 24 April 1999.
2) How Spiders Make Their Silk, “Discover,” 19 (10): 34 October 1998.
3) BBC News http://news.bbc.co. Uk/go/pr/fr/-/2/hi/science/nature/3129777.stm 2003/08/07.
4) Answers in Genesis http://www.answersingenesis.org/creation/v13/i3/hairy.asp 2006 Dr. Wolfgang Kuhn, Professor of Biology, U. of Saarbrueken
July & August 2006
