I thought this was fascinating -- scientists have modeled how cats drink. Naturally, once you have a model, you want to see how well if fits the data. For example, is there an optimal lapping speed?
After calculation of things like the Froude number and the aspect ratio, they were able to figure out how fast a cat should lap to get the greatest amount of water into its mouth. The cats, it turns out, were way ahead of them — they lap at just this speed.
Score one for the Darwinian camp!
And it's generalizable:
To the scientific mind, the next obvious question is whether bigger cats should lap at different speeds. The engineers worked out a formula: the lapping frequency should be the weight of the cat species, raised to the power of minus one sixth, and multiplied by 4.6. They then made friends with a curator at Zoo New England who let them videotape his big cats. Lions, leopards, jaguars and ocelots turned out to lap at the speeds predicted by the formula.
Don't waste your time watching your cat, though. At 4 laps per second, it's just too fast to see.