What do we know about spiders? They have 8 legs, they hide in dark corners and suddenly scuttle out, and a lot of people think they’re scary. Right? Arachnophobia, the fear of spiders and other arachnids, is very common but even spiders that are venomous to humans don’t seek us out but rather bite as a defence mechanism. Spiders get a bad press but the reality is that they are more scared of us than we are of them and if they weren’t around we’d be overrun with flies and other insects. They are fascinating creatures and we should protect them, not squish them.
Why are many people uneasy around, or even terrified of, spiders? It could be an evolutionary throwback to a time when avoiding venomous creatures was a necessary survival trait. It could be that the society we live in portrays spiders in a negative way, such as in this episode of the children’s series The Trap Door. It can be the result of a negative experience with a spider: my daughter, who was previously quite keen on anything creepy-crawly, turned over in bed one evening to find herself face to face with a rather large house spider and has been frightened of them ever since. Seeing an adult react in a negative way to a spider can also lead children to learn that there is something to be scared of.
What is a spider?
Spiders are arthropods, which means they have a hard exoskeleton. They are arachnids, along with mites, scorpions and harvestmen, and have 8 legs, each with six joints. Dense tufts of hairs at the ends of the legs, called scopulae, help the spider to grip. Spiders are made up of two body parts; the cephalothorax at the front, and the abdomen at the rear. They have chelicerae, or jaws, which may be shaped like fangs or pincers. Spiders have 8 eyes, and the way the eyes are arranged will often give a big clue as to who is eyeing you up. Read about spider eye arrangements here. The pedipalps at the very front of the spider are often mistaken for another pair of legs but are actually for sensing touch, handling food and, in males, for sperm transfer to the female during mating. The pedipalps of male spiders often have little ‘boxing gloves’ at the end, helping to identify the gender of the spider you are looking at. Spiders are known for spinning silk and they do this from between four and six spinnerets. Read about spinnerets and spinning silk here.
Spiders are famed for web building and the results can be beautiful, especially on a frosty morning. Webs can take two or more hours to build, some spiders make a new one every night and many eat the old one as a source of nutrition. The webs are made to catch prey and may catch an insect mid-flight, or be designed so insects fall into them. Spider silk is a form of protein and weight for weight it is five times stronger than steel. Spiders can produce up to seven different types of silk from their spinnerets, all with different uses, including cribellate or sticky silk which helps ensnare insects in the web. Further information on silk can be found here.
There are several different types of web: the familiar orb web of the garden spider, sheet, tangle, purse, funnel, lace and radial webs and the type of web will give you some good clues as to what type of spider made it. If you see an orb web with a bit missing, it was probably made by Xygiella x-notata, the missing sector orb weaver. Money spiders make sheet webs and wait beneath for their prey to fall in. Tangle webs are what we associate with cobwebs and are made by the cellar spider, Pholcus phalangioides, which despite it’s small body can take on and eat a giant house spider. Funnel webs are found in grass and brambles and the spider sits at the back of the tunnel and then dashes out when it senses movement and possible prey. Read all about webs here and watch time lapse web building and fly capture here.
Web of the common orb weaver, Araneus diadematus
Not all spiders make webs. Jumping spiders do what their name suggests and leap on their prey. They have powerful forelegs for jumping and the arrangement of the eyes means they can see all around them. Hunting spiders such as wolf spiders have long legs and can run very fast. Despite the fierce name, the female wolf spiders are very maternal and they carry their baby spiderlings around on their backs. The crab spider isn’t as fast but sits and waits in flowers for its prey to turn up. It is well disguised and by the time the hapless insect has realised the spider is there, it’s too late.
Crab spider, Misumena vatia, and prey. Credit Peter Harvey
So, what have spiders ever done for us?
The answer to this is quite simple. Spiders consume an astonishing 400-800 billion tonnes of insects every year which is more than the total amount of meat and fish consumed by humans in a year (1). If it weren’t for spiders, we would be drowning in insects and life would be extremely unpleasant at best and impossible at worst. Spiders also provide food for birds and are an important part of the food chain.
Let’s also dispel some spider myths. No spider in the UK is considered deadly or dangerous and spider bites are incredibly rare. Problems from spider bites usually arise because the skin has been punctured and bacteria have entered the body, rather than from the spider injecting venom. The noble false widow is often the subject of sensationalist press stories in this regard but, despite what certain newspapers would have you believe, they aren’t deadly and secondary bacterial infections are the cause of any discomfort following a bite.
If you do find a spider in your house, and would prefer it not to be there, gently remove it with a glass and piece of card, or invest in a spider catcher which allows you to deal with your unwanted visitor at arm’s length.
Let’s finish with this quote from Donna Lynn Hope: “Spiders are anti-social, keep pests under control, and mostly mind their own business, but they somehow summon fear in humans who are far more dangerous, deceitful and have hurt more people. Of the two I'm more suspicious about the latter.”
(1) Extraordinary Insects, Anne Sverdrup-Thygeson
Further reading
Help for arachnophobia
UK Spiders Facebook page - a friendly Facebook group with a surprisingly large number of recovering arachnophobic members
The Book of the Spider, Paul Hillyard - all things spider from mythology to interesting facts
Spiders: Learning to Love Them, Lynne Kelly - written by an Australian who conquered her disabling fear of spiders
Courses to help with overcoming a fear of spiders are available in London and East Sussex.
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