Observations on Marriage from a [almost] 17 year old

I was doing biology when I came across something that I thought was interesting. I was reading about the different kinds of symbiosis and realized that they are very similar to the different kinds of marriages that are out there. Here are the 3 different kinds of symbiosis that I have edited so they apply to marriage. (I shared this with my mom and she thought it was pretty funny.)

1. Mutualism – A relationship between a man and a woman where all benefit from the association.

2. Commensalism – A relationship between a man and a woman where one benefits and the other is neither harmed nor benefited

3. Parasitism – A relationship between a man and a woman where one benefits and the other is harmed

(There is a fourth kind that they didn't mention in biology because it doesn't make much sense--but this kind of marriage does exist:)

4. ________-ism (<--can't think of a good name. any thoughts?)- a relationship between a man and a woman where neither one benefits.