Compared with many animals the sex life of the humble spider can seem bizarre to say the least.
Before looking for a mate the male spider needs to prepare himself for the deed. First he builds a specialised sperm web used to catch a droplet of sperm which is then collected through the front palps – those feelers which look like an extra pair of legs at the front of his body.
The palps are able to absorb the sperm into storage organs at the tip, and store it until a welcoming female is encountered. This is called sperm induction and is a necessary process as there is no internal connection in the mating process.
For web-making spiders the hazards of courtship are considerable. A female spider’s web can become a final resting place for an unlucky male; if he fails to send out the right signals, he may become lunch.
Survival strategies have the male orb-weaving spider waiting on the outskirts of the web and tapping a romantic tattoo to entrance his mate into submission. Certain male flower spiders can dabble in bondage by tying up their intended in silken strands. However, he’s not some kind of eight-legged rapist – the female can break free if she wanted. In same-size spider breeds recognition and acceptance appears to be a simpler process.
Once accepted, the next step involves the palps being used as a syringe to inject the sperm bubble into what is effectively a sperm bank on the underside of the female’s body. This is stored and used to fertilise each batch of eggs. It can take several hours for the transfer to occur and in some species it can be a hair-raising experience as the hairs rise and fall rhythmically.
It may sound kinky by human standards but it’s just another example of the mind-boggling diversity of animal behaviour.
