Moxie’s Designer Highlights
New Uses for Old Patents
Our uses for good bonding agents are almost endless. We glue craft items, chipped china, broken toys, furniture which has come apart, and so on. The list seems endless. There are industrial uses and medical uses for glue too. During the Vietnam war, for example, the American army developed a medical superglue for treating wounds. This product was less than ideal however because it required dry surfaces in order to set. But, as everyone knows, wounds tend to be wet and yucky. Certainly there would be no dry surfaces inside the body. Now English scientists are getting into the act. Actually they are working with a glue which was invented long ago. They are just learning how to make use of this special product.
Ever since the creation, mussels have effortlessly produced a superglue which is so remarkable that it seems almost too good to be true. Mussels, by the way, are bivalves (like clams). They enclose their soft tissues inside two similar shell halves. These protective hard parts do not leave these creatures a lot of leverage for maintaining their place in the environment. They have no hooks, or fingers to grab hold of a surface. Typically they live in the sea near the shore, where their chances of being smashed on rocks or driven out to sea, would normally be high — if it were not for their special capacity. The mussels simply glue themselves to the rocks. Then whatever violent storm produced waves pound over them, or however insistent the advance or retreat of the tides, these creatures simply stay put.
Now let’s see. These mussels glue themselves to rocks while under water. The glue then sets and never lets go. That is some glue! The English scientists expect that this glue will be useful for closing wounds, mending broken bones and chipped teeth. The glue is nontoxic and does not produce an immune response. It can bind to metals, glass and plastics among other surfaces. It was discovered early on that mussels have little to share with anyone else. Harvesting from the animals simply did not work. Thus what the scientists have done is to isolate the appropriate mussel gene and to insert it into tobacco plants. Tobacco is easy to work with and there is no danger anyone will eat the tobacco plants since the nicotine would kill them.
Thus we expect soon to benefit from a wonderful natural product, far more versatile than our own manufactured adhesives. Moreover mussels are not the only marine animals with special bonding capacity. Brachiopods also enclose themselves within two shells (but one is larger than the other) and their soft tissues are very different from bivalve anatomy. Brachiopods too glue themselves to rock faces or to sandy or gravel surfaces. Moreover this glue sounds similar in properties to the mussel glue. As one scientist remarked concerning brachiopod glue: “Many scientists and chemists have pondered the chemistry of this glue, so strong that it makes our synthetic cements seem ludicrous by comparison.” (P. D. Ward. 1992. On Methuselah’s Trail: Living Fossils and the Great Extinctions. W. H. Freeman & Co. p. 56) And so while some scientists speculate about how evolution “perfected” this glue over millions of years, we turn our attention to the real designer of these products. Let’s give praise where praise is due.
IT’S OFFICIAL: BEES’ BLUEPRINT IS BEST
The hexagonal arrangement of walls in a honeycomb results in a strong but light-weight structure. It is obvious that the bees’ building design is good, but is it the best possible choice? Up until 1999, no one could say for sure. We expected it was most efficient but the idea was hard to prove mathematically. Finally in June of this past summer, Thomas Hale of the University of Michigan, presented a suitable proof. He concluded that “a hexagonal honeycomb has walls with the shortest total length, per unit area, of any design that divides a surface into equal sized cells.” (Science August 27, 1999 p. 1338). Moreover, once the proof was developed, it was realized that the mathematics was uncomplicated. It did not even require the use of a computer!
The problem for mathematicians was that no one knew whether equal numbers of walls were best or whether cells with fewer and more wall parts would fit best together. Could a more efficient honeycomb be produced from pentagon cells for example alternating with heptagons? What Dr. Hale did was to calculate whether one cell’s gain in efficiency (use of minimum wall material) could compensate for another shape’s loss in efficiency. In the end he found that the hexagon worked best. All the cells would be equally efficient. This realization, that the bees build their hives to the best possible specifications, should not come as a surprise to us. Their architect, after all, is the Designer of all things.
ANOTHER TOUCHING DISCOVERY
The expression “out of sight, out of mind”, certainly applies to moles. Typically unsociable, these little insect eaters (insectivores) spend most of their lives underground. Thus the special design features of these animals are not well known. In actual fact, these little mammals are among the most talented of diggers. There are several North American species, but one is especially interesting. But the star-nosed mole, Condylura cristata is not a typical mole. It is actually much more interesting! Living in the eastern part of our continent, from Northern Quebec and Labrador to Manitoba and south the Okefinokee Swamp of Georgia, this little mammal actually prefers to spend most of its time in ponds. But that is not its claim to fame. Up to 13 cm long, the star-nosed mole is said to be peculiar at both ends. While its tail is a weird shape, the snout is the most remarkable part. It resembles a disk which is surrounded by twenty two moveable fingers. Apparently this is an organ of touch so sensitive that the information it produces is almost as detailed as vision. No other creature, that we know of, has a similar feature. However it is the unique pattern of development of this organ in the unborn mole that has biologists really excited.
Throughout the animal kingdom, scientists tell us, the development of limbs and digits or whatever projects from the main body surface, all develop from a similar set of controlling genes. Thus the pattern of development follows a very predictable sequence of events. This is not however the case with this creature. Ridges develop from front to back along the snout. Assume that the nose is the front end of the snout and the back end is near the eyes. Eventually each ridge becomes detached from the snout except at the front. These “fingers” then droop forward from their point of attachment so that what was once the back end of the appendage, is now the front end. The reason that scientists are so excited about this developmental process is that the foundation is critically important to the later success of a machine, building, body plan or whatever may be under construction. If the first stages are go wrong, of course, the whole system will be a flop. This applies to development of body plans as well as to manufacturing. Thus the success of an animal later in life depends upon the early stages of cell division in an embryo. No other animals is known which changes front and back orientation of a body part at maturity. Since this is so unique, scientists wonder how the mole obtained its special talents.
Here is a hint for you to consider. The horseshoe crab has a completely unique eye with sensitivity to light a million times greater at night than in the daytime. Scientists wonder how the horseshoe crab obtained its special talents. Could it be that both these creatures were specially designed? Do you suppose there are other special cases out there in nature? Maybe you know of some already. Consult your friends and see if they have any ideas on this interesting topic.
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