Savory - Arachnida 1977

36
The Spider's Web
The webs that spiders spin are objects of an exceptional interest which
they unquestionably deserve. They are the chief among the few things
that invertebrate animals build or construct, and they are made of
silk, in itself an extraordinary substance. Beavers build dams, birds
make nests, bees make combs, termites build cities, but only the spider
constructs a trap. Silk is produced by false scorpions and mites and by
some insect larvae, but they do so for occasional uses only, whereas
the spider depends throughout its life on constant silk-secretion. \Vhat
Tilquin calls "sericiphilie" is its outstanding characteristic. Probably,
too, webs have attracted attention and have acted so successfully as
advertisements that much of man's original interest in spiders, and
hence in other Arachnida, can be traced back to his seeing spiders'
webs. In other words, were it not for their webs, spiders would be of as
little concern as are silverfish or centipedes.
These basic facts raise many problems. How did web-making
originate? How have the different kinds of webs come into existence?
Why does each different web-pattern belong to a different family of
spiders? How does a spider find its way across its web, and how does it
make its way back? And so on. There is no end to such questions, and
the best known of all webs, the geometric or orb-web, is the most
baffling of them all.
The earliest of all spiders cannot be supposed to have been a webspinner:
probably, like other Arachnida, it was a wanderer, devouring
what it was able to catch, but, because it was a spider, trailing a thread
of silk behind it. To this it is reasonable to add the habit, widespread
among all cryptozoic animals today, of coming to rest in some crevice or
hiding-place, which gave it protection and shelter.
From here short sallies to pounce upon passing unfortunates would be
an obvious way of life, and a return to safety would be guided by the
action of the lyriform organs. Thus there began the use of silk to help
in the securing of food, for repetition of this habit would have had an