The Sing ability is one of the social abilities available in the Creature Stage, used to impress other creatures. All creatures are capable of using the Sing ability (with the exception of some robotic creatures; see below), and a high Sing is considered absolutely essential for an effective social or balanced creature, simply because a creature with no other social skills (such as a well developed, predatory Carnivore) will still have Sing. Note, however, that the Social Creature Stage trait can still be acquired with a low Sing level, but with much more difficulty.
Sing can only be acquired from mouths, in the same way that Charm can only be gained through Details, Dance through Feet and Pose through Hands. All of the mouths in the basic parts set feature the Sing ability, with ability levels ranging from 1-5. The Carnivore mouths range from Sing 1-3, while the Herbivore mouths range from 1-5. The Omnivore mouths are the most versatile, with both Sing and Bite ranging from 1-5. In the Spore Creepy and Cute Parts Pack, many new head styles became available. These heads also offer Sing at various levels, with the 'Cute' heads offering higher levels of sing. The Spore Bot Parts Pack, on the other hand, offers two heads, called Cantops and Clamps, which have no Sing level, making it possible to create a creature with no social abilities. This is highly discouraged, as trying to socialise with such a creature will cause your game to crash.