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Chase a spider
If you want to live and thrive, let a spider run alive! Interesting saying, right? Have you ever noticed some webs in the corner of the walls that you just carelessly sweep away? How frustrating it is to see these webs invading your beautiful and clean house? I am sure you have not noticed the expertise with which these webs are spun. Who spins them?
Spiders! They are a group of invertebrates found throughout the world from the sea shores or from the zones where splashes reach the hot sands of the deserts. It is the most common animal who lives from high mountains and great forests to home garden and even in the bathroom. Pretty boring but in reality when you closely inspect spiders — their lifestyle, appearance, movement and various other characteristics —you’ll find them quite fascinating.
People think that it is just a small insect making webs. But you would find it funny to know that spiders are not insects! They belong to the class known as arthropod. Arthropods are a large group of invertebrates (animals without backbones) that have spinning glands used to produce silken threads and webs. Spiders have eight legs while insects have six legs and an antenna.
It is almost impossible to tell the species because there are 40,000 species of spiders throughout the world.
Body parts
Their body consists of two parts: fused head and thorax (cephalothoraxes), and an abdomen. The fused head has two fangs which they use to capture the prey. They have eight legs, each of which is controlled by more than 30 muscles, and eight eyes so that they can look in all direction but they usually use their sense of touch which is better-developed than their eyesight. Spiders have hair on their feet which they use to taste things. The web is produced from the back part of the abdomen which is called Spinneret.
Size and colour
Spiders range in size from less than 1.0 mm to more than 10 cm in length, with a leg span of up to 20 cm. You all know that camels can store water for weeks in their hump, but they are so large; similarly, while spiders are so small, they too can store food in their extensive digestive system for weeks or even months without the need to catch prey. Pretty unique, right?
Spiders are found in brown and black, red and green, white, black and in almost every colour. A single spider may have just one colour or maybe two colours. We also find spiders that bear colours such as red, black, brown, grey, and yellow in a magnificent pattern at the same time. This gives the impression of it being swaddled in some kind of cloth.
Respiratory and digestive systems
Another unique feature of spiders is that they can respire from two distinct respiratory organs that are trachea and book lungs. Weird name right? But the reason why the organ is called book lungs is that it looks like the pages of a book.
Spiders are carnivorous animals and they have an unusual way of digestion that begins outside the spider’s body. When the spider catches its prey, it uses its venom to paralyse the prey through its sharp fangs and then the spider vomits juices containing the digestive enzymes into the wound of the victim to break down and liquefy its body tissue. This liquefied tissue is then drawn through the spider’s mouth and into its body by the sucking action of the stomach. Two mechanical filters in the mouth prevent solid food particles from passing into the digestive system.
Brain
A spider’s brain is relatively highly developed, enabling spiders to easily adapt to changes in their environment. Some species use their sense of touch and brain more than their eyesight which is not well-established when they are young.
Silk glands
Nearly all spiders produce silk composed of the protein fibroin. This is the same protein produced by silkworms, the larvae stage of certain silk moths. Each spider has four to eight different kinds of silk glands in its abdomen, and each gland produces a different type of silk with different properties. For instance, the cocoon produced by the gland is different from the silk gland that they used to catch prey. A spider silk thread is as strong as a nylon thread with much more elasticity.
Web
The web patterns vary considerably, depending on the species of spider. Perhaps the most recognisable web is the circular orb web, in which an outer framework supports a continuous spiralling thread and a series of threads radiating from the centre of the web. You might have seen this one in your garden. Other web types may have a more irregular shape. Some spiders build irregular, flimsy webs. Common house spiders construct funnel webs, flat silk sheets with a raised tube in the corner that serves as a retreat for the spider. Cobweb spiders build an irregular silk meshwork with sticky threads at the bottom that trap insects. Sheet web spiders construct a horizontal silk sheet with a dome, from which the small spider hangs upside down.
The size of a web depends on the size of the spider. Whether the web has a tight or wide mesh depends on the size of the prey the spider expects to capture. Spiders usually weave their webs at night, completely relying on their sense of touch. So if you want to see spiders spinning web, just go to your garden, if you have one, and start observing the borders of trees and shrubs. You will be sure to find one. I have observed that they can complete their web building in less than 30 minutes if the wind is not blowing.
Notice the time when the spider is in the process of weaving its web, it will remind you of the old lady who spins cotton on the moon or your grandmother knitting sweaters. Another interesting thing that one observes is that their silk gland is not just a single thread; it is like three or four different threads twisted together —this adds to the strength of that thread.
Types of spiders
The spiders are categorised according to their hunting ability. There are two types, web spiders and ground spiders. Web spiders use the web to capture prey while ground spiders wait for the prey to come near and then pounce and kill the prey with their strong chelicerae (fangs). The ground spiders also include jumping spiders, which, depending on their specie, can leap up to 25 times their body length.
Species of large spiders can deposit several thousands of eggs within just a few minutes. Eggs of the size of a moth ball are also found. I once found one such egg in the garden; on closer inspection, I saw hundreds of tiny (1mm in size) spiders coming out of the egg in a row on a web exactly what I had read about them.
When and where to find spiders?
Summers are coming and this is the season in which spiders usually come out from their homes to hunt for prey. The Golden rod spider or Flower spider is gifted with many Flowering plants, for example rose. The Golden rod spider is white in colour which changes from white to yellow and is not dangerous so if you want to play with it you can.
Jumping spiders are also found on rose plant and a spider with two legs in upward direction. This specie boasts of many colours. Look in an open gutter with no water flowing in it, a spider may be there. Another place where you can find a spider is when a web of any kind is present.
Try finding spiders if you are interested and you will find the research fascinating.
You will see that they can fly using their web. They can throw webs a long distance to the desired location and may walk on it or pull themselves. Once again do not kill the spider, because you never know one of them might bite you and you might become the next Spiderman!
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