definition of "what is right" had to be instilled there
Actually no it doesn't. Right and wrong is not instilled in any single person. It is learned through interaction as we develop things like empathy.
Humans are social beings, and thus our every action has consequences that affect not only ourselves but those around us. This is an observable fact and there for any thinking being to comprehend and evaluate.
From the time we are born there are certain things (like homan contact, not being left alone for long periods of time etc) that help us in the first couple of years as our brain develops which alot of the time determines the extent of our perception of what is good and bad as well as our level of empathy toward others. If you look at the classic example of children who were either lost or abandoned and raised by animals, they have no sense of morality in human terms. Their morality is learned from the animals through observation and interaction.
At what point in our evolutionary development did God install our morality, so that none of our closest animal relatives have it?
God did not instill our morality, because if he did, he gave a higher moral code than he has.
There are lots of animals that display morality within their social groups, just as we do. Whether people like or not, the fact is we are animals as well regardless of whether a god exists or not. Morality isn't some airy fairy notion, it is simply a standard of behaviour within a social context. Apes, dolphins, dogs etc are all social creatures and their survival, much like ours depends on standard of behaviour that would ensure their survival.
I want to be happy and avoid pain. Because we are the same species and our brains are pretty much wired the same, I would also assume others want to be happy and avoid and suffering. Bearing that in mind, even though I have my own goals in life and other peopl have theirs, it is hoped that we would want to pursue that life without causing any pain and suffering to others and vice versa, hence the reason we have laws in place to help weed out those that would want to intentionally cause disharmony.