Page 68 - The Miracle in the Spider

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