Damon Cullen, of Green Island School, asks :-

Which is the most poisonous spider in the world?

Simon Pollard, an arachnologist at Canterbury Museum whose research on spiders that live in pitcher plants featured in a recent BBC series Planet Earth, and who has just returned from Kenya where he has been working on blood-drinking jumping spiders, responded.

As a spider biologist (arachnologist) who has been bitten many times by spiders (almost always my fault), I have never had an effect from the venom that was more than a bee sting and usually much less. However, there are some spiders that produce venoms that can be very dangerous to people and the top three would be the Sydney funnel-web, the black widow in North America and the Brazilian wandering spider. The venoms from all these spiders have killed people, but now there are anti-venoms available and further deaths have not been recorded.

I would not want to be bitten by any of this trio and I would certainly not want to repeat the experiment a doctor in the US in the 1930's carried out with a black widow spider. He was dubious that the black widow produced a venom that was particularly dangerous to people, so he allowed himself to be deliberately bitten on the finger and recorded what happened. After 12 minutes, his assistant had to take over the note-talking because the doctor could not write. After 15 minutes he was taken to hospital where an hour later the doctor who saw him, wrote, 'I found him in excruciating pain, gasping for breath and reclined in a tub of very warm water. I do not recall having seen more abject pain manifested in any other medical or surgical condition. All the evidence of profound medical shock were present'. During the night, his assistant wrote that the bite victim 'became so upset mentally that he was afraid if firm control was not exercised, he would go insane'. Fortunately, he did recover and I am sure never repeated the experiment.