Quote:
Originally Posted by mrs fish  My mum and dad swear by conkers placed around the floor edges to keep the spiders away  , I told people about this on the Autumnwatch message boards last year 
The theory is that the intruding spider thinks the conker is a much larger spider. |
I don't think this is the case. Spiders have good senses, based on sensing air movements and vibrations, as well as chemo-senses. They have poor eyesight (apart from a few families like jumping spiders and wolf spiders), and other spiders would generally be detected through direct contact or contact with silk (female spider silk contains phermones, strands of which the males follow to find the female). If conkers are repellant to spiders it's probably because they contain poisons (they're poisonous to people too, after all). Why specifically conkers I don't know, as spiders webs can be found on lots of (more poisonous) plants.
Greg