What causes cobwebs?
Cobwebs come from spiders, even if you do not see the spider. Indeed, there are quite a number of arthropods that can produce a sort of silk similar to that produced by spiders. For example, silkmoths or other butterflies produce a silk that is involved in some aspect of reproduction or development. The silk production may be used to produce a shelter for the eggs or for the pupae, e.g. “Cobwebs,” as they are commonly known, are built by spiders. Each spider species has its own pattern of weaving. Even the more or less irregular pattern shown on this picture is typical for the species producing it. Some spider species do not produce webs at all – jumping spiders, for example. Some species build a very regular web every morning, destroying it in the evening again, until they are covered with too much dust for hunting. Then they abandon it and build a new one somewhere else. Why do you never see a spider in it? You are too late. Fresh webs are nearly invisible. When you see a web easily
