Page 68 - The Miracle in the Spider
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68                    THE MIRACLE IN THE SPIDER






















              Ptocasius is a species of spider which joins two leaves together to make its nest.
              It uses its silk as glue to join the leaves together. This nest enables it to hide at
              night and when hunting.

              thought this would be as simple as getting silk from silkworms, but later
              it dawned on them they were wrong.
                   Evolutionary zoologist Fritz Vollrath, of Aarhus University in

              Denmark, realised, as a result of his research, that it would not be possible
              to make it by taking it directly from spiders. This being the case, scientists
              then came up with the idea of "the production of artificial spider silk" as
              an alternative. But, before that, it was necessary for the researchers to find
              out how the spider produces the silk. This took quite a few years. The
              zoologist Vollrath discovered an important part of the method in his later
              work. The spiders' method is remarkably similar to the process used to
              manufacture industrial fibers such as nylon: spiders harden their silk by
              acidifying it. Vollrath concentrated his work on the garden cross spider
              known as Araneus diadematus and examined a duct through which the silk
              flows before exiting. Before entering the duct, the silk consists of liquid
              proteins. In the duct, specialized cells draw water away from the silk

              proteins. Hydrogen atoms taken from the water are pumped into another
              part of the duct, creating an acid bath. When the silk proteins make
              contact with the acid, they fold and form bridges with one another,
              hardening the silk. 22  But of course the formation of the silk is not as
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