| Will you step into my parlour?
 By Nutan
        Shukla
 WITH many species of spider, the
        female is threateningly large in comparison with the
        male, and may easily mistake him for a trapped insect and
        proceed to eat him. So any male wanting to mate must
        approach with utmost caution. Different species of spider
        use different tactics. A male may frantically wave his
        legs or his pedipalps (the sensory appendages on his
        head), or he may tread carefully over the females
        web using a complicated dance-like step to distinguish
        himself from any other insect. Alternately, he may resort
        to bribery and offer her an insect as a distracting
        snack.  In the case of Pisaura mirabilis, during
        breeding season these spiders scurry about in fresh green
        vegetation in search of a female. As soon as they come
        across her tracks or the signal thread that the female
        drags behind her, they set off with new energy to hunt
        for flies. When the male catches a fly, it immediately
        starts entwining it in its cobweb until a white ball is
        formed.
 He carefully holds the
        wrapped fly in his mouth and ceremoniously carries it in
        its silken packet to the female. When he sees her, he
        freezes in a bizarre, grotesque position, and then, very
        courteously, presents his gift. He stands in front of the
        female spider like an enigmatic and incomprehensible
        sculpture at an art exhibition. The male rests on the
        bottom of his vertically extended abdomen and on his six
        legs. His fourth pair of legs are raised over the fly
        packet that he is holding in his mouth. The female spider, who
        must be stunned by this unusual sight, slowly moves
        towards him as if she cannot believe her eyes. She then
        accepts the wedding gift, tears up the packet and starts
        sucking on the fly. Should the male turn up without a
        gift, he is in for it. The female will eat him up. But
        spiders can also cheat. Some bridegrooms pack up the
        remains of a fly carcass for their date. Some males are
        even more clever. They carefully wrap up nothing at all
        and give their female a large but completely empty cocoon
        to unwrap. The wrapping is important because it takes a
        female a long time to unravel it and get at her prize,
        and while she is preoccupied the male has long enough to
        mate without being eaten. With tactics like these, speedy
        sex becomes the order of the day. Male spiders employ even
        more varied techniques to avoid being their own wedding
        breakfast. Some males overcome this problem by making a
        series of special visual signals from a respectful
        distance. Others tap out a code of distinctive vibrations
        on the females web, tweaking the threads in a
        rhythm that lets her know that they are males and not
        meals. Some males are more assertive and put the female
        into a kind of hypnotic sleep by biting her in a special
        way, or by tying her down with silken threads and then
        mating with her when she is well wrapped up. Many of
        these tactics work and the males live to mate another
        day, but from time to time they fail and the female
        satisfies her protein hunger by sucking her mate dry
         an undeniably efficient way of giving her newly
        fertilised eggs a nutritious start in life. Tarantulas or
        bird-eating spiders do not have good eyesight, so they
        communicate by touch. When a tarantula male meets a
        female, he signals his presence by using his front legs
        to drum a tattoo on her body. She is alarmed, and raises
        her front legs ready to strike. It takes a lit of
        soothing and stroking from the male to calm her down. At last she raises her
        body and opens the lethal fangs that could finish him off
        with a single bite. But he is not unprepared. He has
        hooks on his front legs specially for holding her jaws
        apart. Safe at last, the male inseminates the female and
        then makes his retreat as quickly as possible. In the above mentioned
        cases it is one kind of cannibalistic tendency where
        adults eat adults, but there are cases where adults are
        eaten up by their offsprings. Once the life-giving and
        protective roles of the adults have been completed, they
        are still good for a meal. The female wall spider often
        dies before her young are ready to leave their cocoon
        nest. If this happens, they devour her body when they
        finally emerge. In this way they are provided with an
        easily obtained first breakfast before they set off to
        explore the world. A similar occurrence has been observed
        in certain sheet-web spiders too.  
 This feature was published on
        September 5, 1999
 
 
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