Sydney funnel-web spider

Under a social business dinner recently the newly appointed CIO of Westpac, Clive Whincup, who is a literate of many subjects, told us that the neurotoxin from the Sydney funnel-web spider only was deadly to primates.

This is particularly interesting given that there are no other indigenous primates in Australia than the humans.

The neurotoxin causes wholesale release of neurotransmitters, especially acetylcholine. The puncture wound is intensely painful. Although the bite of the funnel-web spider (Atrax robustus) can be and has been fatal, there have been no reported deaths since the introduction of the antivenom in 1981.

This may be because all Sydney funnel-webs live within commuting distance of the Opera House, a relatively small area dense with well-supplied hospitals.

Although extremely toxic to primates, the venom appears to be fairly harmless to many other animals. So apparently science do not have an answer to why the funnel-web spider has developed a toxin that is harmless to many of its targeting small animals. It has been suggested that these animals may be resistant to the venom's effects due to the presence of Immunoglobulin G (lgG) and possibly cross-linked IgG and Immunoglobulin M (lgM) inactivating factors in their blood plasma that bind to the toxins responsible and neutralise them, or it may involve a non-specific reaction due to the highly basic nature of the toxins.

In other words, we don’t know why the funnel-web spider has developed a neurotoxin that is only able to kill the English convicts and immigrants at their arrival in Sydney more than 200 years ago…