Recently, there was a little discussion on the use of animal bonus tiles in Singapore Style mahjong in the rec.games.mahjong newsgroup.
One poster had asked about how animal bonus tiles were used, and I had responded with what I know about animal bonus tiles. Some of this was described in an earlier post Mahjong, Singapore Style.
To the best of my knowledge, animal tiles (comprising of cat, rat, cockerel, and centipede) are special bonus tiles found predominantly in Singapore Style mahjong. Each animal tile gives the player one double/fan/tai. Additionally, a pairing of either cat and rat or cockerel and centipede (i.e. predator and its prey; this is known as a ‘bite’ or yǎo locally) results in an instant payout. Not every player in Singapore uses the instant payout rules though.
Interestingly, Strauser and Evans  describes a different way of using the predator and prey tiles whereby a player exposing a predator tile after its corresponding prey tile has been exposed can capture that prey tile, resulting in two fan for the player exposing the predator tile, and none for the player who earlier exposed the prey tile.
The even more interesting thing was that a fellow poster from Singapore stated that he plays Singapore Style mahjong (with various groups of people) with the use of prey-capturing! This was certainly surprising to me, in a way. I have been trying to survey the rules for Singapore Style mahjong for some years. The previous posts I wrote to describe Singapore Style mahjong are almost two years old! Every Internet source I read did not mention this prey-capturing rule, and I had also never encountered such rules when playing with various groups of people for some twenty years. So, is this rule authentically Singapore Style?
I am not particularly convinced yet, partly because all available documentation (no matter how unofficial, given that Singapore Style mahjong is not a standardised variant of mahjong) had not mentioned this particular way of using animal tiles. For example, the Wikipedia article on Singaporean Mahjong scoring rules does not mention this at all.
Yes, I do believe that there are many groups of people out there in Singapore (and all over the world) playing Singapore Style mahjong that would include variant/house rules. For all I know, this could be one of those variant rules that is quite popular, but for some reason or another, I have yet to encounter it at live play with any group.
I would appreciate any leads on this from you readers out there! Send me a comment if you do play with this rule in Singapore Style mahjong.
1. Kitty Strauser and Lucille Evans, 1964, “Mah Jong, Anyone? A Manual of Modern Play”, Tuttle Publishing. A more up-to-date and revised version with additional material by Tom Sloper was published in 2006 as “Mah Jong, Anyone?: A Manual of Western Play”.