Quote Originally Posted by meatwad
The main difference is that the vegetable matter has been digested fully and transformed into materials that are being used by the deer. If the wolf was a parasite, it would never give the deer a chance to use this material to grow. The same applies to the placenta; the baby is not eating part of the mother; it is using preprocessed material that was never used by the mother.
Speaking as somebody with a pregnant wife, trust me, she's able to grow in addition to the baby itself. Crap, I think she saw that.... no baby, you're not starting to show yet.... *ducks*

I'm afraid you're going to have to distill this parasite theory for me a little more. I'm simply not getting it. No organism on the planet that lacks photosynthesis feeds itself independently. In fact, even plants require nutrients they get out of the soil from the byproducts of bacteria biodegrading other lifeforms. Your point about life forms that can produce their own food independently is lost on me, because I cannot think of a single example.