蜘蛛是怎么织网的？

形容一个人恋爱了我们常说他/她“坠入情网”，可见爱情对人的影响之大。不过，要说到网，在自然界中，最会织网的怕是蜘蛛了。只不过，蜘蛛这张网不是用来网住爱情的而是用来捕食的。难怪，人们也会把张开情网的人比作猎手呢。闲话少说，我们还是来探究一下蜘蛛究竟是怎么织网的吧。

To spin a tale about the spider, an arachnid¹, we must first examine the common thread that ties them together...the way they produce the silk they use to weave their webs, as well as other contraptions, to suit their particular needs.

Spiders differ from insects in that they have eight legs, eight eyes, in most cases, no wings, and have only two parts to their bodies, one of which produces silk. They are found in a host of climates, can scurry² across the ground, can scale plants, and can skate on, and live in, water. These factors determine how the spider uses it's silk, and what type of silk it produces.

The production of silk begins in certain glands³ located in the abdomen⁴, or belly⁶, of the beast. Spinning organs at the tip of the abdomen, contain many tiny holes, and function much as a sieve⁷, through which the silk is pressed. The silk strained through is in liquid form, but immediately takes on a solid form, much like cotton candy does, when exposed to air.

The spider creates a variety of types of silk, each of which serves a separate, yet distinct function. Spiders use the sticky kind to spin webs, to catch and to hold the insects they invite into their parlors⁹ until they are ready for dinner. They use the non-sticky, stronger variety to tether down the spokes¹⁰ of the wheel, and yet a different kind of silk for their cocoons¹¹.

Even the webs the spider spins differ greatly, depending upon the factors listed above. The most common of all webs we see is the wheel-shaped web. Less common are the so-called "sheet" webs, which blanket surfaces with a funnel¹², or dome⁵ like shape. The trap-door spiders burrow¹³ out their webs, and complete them with built-in chutes, through which their unsuspecting guests fall through, right onto the spider's plate. The web we see least often, is the air-tight, bell-shaped home some spiders build...probably because it is completely submerged in water!

Why aren't spiders caught in their own webs?

In short, startled spiders can be entangled¹⁴ in their own webs, in the same manner as their prey¹⁵. Generally speaking, however, the spider avoids this deadly mishap¹⁶, by differentiating¹⁷ between the various types of silk it produces, and by knowing its home turf.

When the spider weaves its sticky, insect-catching type of web, it builds into it safety threads of the non-sticky variety, upon which it traverses without being snared¹⁸. Its nimble, highly sensitive feet orient the spider about its new home, and past the potential pitfalls¹⁹, to which its prey falls victim. Unless, of course, something, or someone, startles the spider, in which case all bets are off, and the parlor⁸ game is over.

contraptions: 奇妙的装置，稀奇古怪的玩意

sieve: 筛子，滤网

spoke: 轮辐