On a tangential diversion, I have this little offering to present, which I wheel out whenever I'm introducing people to the wonders of invertebrate zoology.
Spiders have an interesting variation on the usual theme of internal fertilisation during reproduction. At the head end, alongside the chelicerae that are modified into a venom sac and fangs in spiders, are two short, leg-like appendages known as labial palps. Which are usually used for manipulating food during feeding. However, in male spiders, they perform a second function as well.
Basically, when male spiders are ready to mate, they spin a pad of silk beneath them on the current walking surface, then squat and deposit a sperm package onto the silk pad. Then, they reverse, insert the palps into the sperm, and syringe a portion of sperm into specialised receptacles in each palp. Then, they go and search for a female to mate with. Upon successfully locating a female, and persuading her to mate, they they insert the labial palps, one after the other, into the female epigyne in order to fertilise her eggs.
So spiders, in short, are organisms that have sex using their cutlery.
