Why spiders have a thin waist

There was once a spider called Greedy spider. He love to eat very much. One day there were two dinners going on in each of the village to the east and west repectively of the one he was in. He wanted to go and eat in both dinners but the problem is that he didnt know when the dinners will start. So he use a long rope and tie to his own waist and handed the other end to his elder son kumar and ask him to go to the east village and to tug at the rope when the dinner there is serve and he will go over. Then he repeated teh same process and asked his second son Adri to go to the western village and do teh same thing.
So came dinner time and Greedy spider was happily waiting. But unfortunately the dinners were serve at exactly the same time. Kumar and Adri tugged at the rope but didnt see their father come so they continued to tug even harder. Poor Greedy spider was thus stuck in between them with the ropes tightening on his waist until he counld not grew fat anymore. That is why til now spiders have a very thin waist.