Spiderwebs are intricate wonders of creation. Spider silk is considered one of the most versatile natural products on earth, and ounce for ounce is five times stronger than steel.
Spiders use silk to transport themselves, often by repelling; also in courtship, and of course, to capture prey.
These beautifully engineered webs come in a multitude of designs. Spiral orb webs are the most familiar, with radiating spokes and symmetrical patterns fanning out in concentric circles. Then there are large, flat funnel webs which serve a dual purpose: they have a funnel at one end to capture prey, and provide the spider’s room and board.
Tangled webs, also called cobwebs, are found indoors such as those woven by the black widow. These may appear disjointed and chaotic, but they’re really an architectural feat. Upper portions are support threads, central zones contain tangle threads, and lower zones have vertical trap threads.
Triangle webs have three spokes fanning out in a triangle with lateral strands connecting the spokes. Unlike other webs the fibers are not sticky, but they appear fuzzy with tiny fibers that latch onto prey. Sheet webs contain dense silk layers that can be flat, convex, or concave in shape; the spider remains beneath the web, waiting to strike its captive.
These intricate forms of construction have been tested by time; spiders have called the planet home for 400 million years.
This Earth Note was written by Carrie Calisay Cannon and produced by KNAU and the Sustainable Communities Program at Northern Arizona University.
