Comment 24 by Zeuglodon :

However, within a few thousand years, cities have emerged and many old dangers have vanished. It is pointless being afraid of creatures like lions, spiders, and snakes in most cities, yet arachnophobia is more prevalent than the actual risks (as posed by most spiders) can justify, whereas city-goers are not "phobic" of guns, smoking, electric sockets, or cars on busy streets, which have a much greater chance of killing them.

A little off-topic but there are many cities in Australia where you can quite easily encounter a deadly snake. Deadly spiders such as funnel webs are common on the eastern seaboard. By deadly I mean something that is going to kill you quite rapidly if medical assistance is not obtained very quickly. Where I live there are some spiders which won't kill an adult but whose bite can cause quite significant loss tissue requiring grafts to repair. I saw one of these in the garden just last weekend.

Michael