My not-so-good friend zaius137, please don't try to derail this thread.
To me, not being a biologist, this was facinating to learn how new features can evolve. The citrate digestion research stated here really was excellent (well, the parts that I more or less could follow). I learned an enormous amount and I'm very grateful to the contributors who shared their expertise so freely.
Please don't try and derail this thread.