Although they hatch with only three pairs of legs, millipedes can reach into adulthood around 200; two for each body segment. It is the animal with most legs in the world. Recent research found that the leggiest species has 750 limbs, but new millipedes are yet to be discovered.
Males can be very creative when it comes to mating. They "sing" and rub their back on the female's curled body (as females see the initial mating attempts as a threat).
The most interesting fact about millipedes is that they live up to seven years. They were also the first animals to live on this planet. The oldest fossil found dates back around 428 million years.
Millipedes are not insects, as they have more than six legs, and they are only considered to be closely related invertebrates.