Reciprocal Altruism and animals

I think Destiny's position of "I behave a certain way towards others because I would want them to behave the same way towards me if I were in their situation," can be appropriately labelled as Reciprocal Altruism.

The concept of "reciprocal altruism", as introduced by Trivers, suggests that altruism, defined as an act of helping another individual while incurring some cost for this act, could have evolved since it might be beneficial to incur this cost if there is a chance of being in a reverse situation where the individual who was helped before may perform an altruistic act towards the individual who helped them initially.

The examples in the wikipedia page mostly say how particular animals meet some, but not all, of the criteria for it and can often be explained by other behaviours such as kin selection. If an animal was shown to engage in reciprocal altruism then I think it would meet the requirement of abiding by a social contract.

Here's a study on reciprocal altruism in dolphins.

I think this is worth reading in order to form a strong argument one way or the other.