I see you altered your original post. I didn't say there was "eternal morality" anywhere...
If there were no beings with higher order consciousness like us to abstract the concept of morality, then it wouldn't be known to be there. But that doesn't mean it's not a part of the process of interacting with other beings capable of feeling physical and psychological pain that we come to recognize.
Other animals demonstrate care, which is part of moral understanding, but they have lower consciousness capacities that limit abstraction of higher order concepts like morality which is a word to describe positive reciprocal interactions between psychological beings.
As such, the morality wasn't invented by us, it was a natural development of interacting with others. If only one psychological being with higher order consciousness to understand morality (human) was present somewhere and there were no other psychological beings (animals) to interact with, they wouldn't be able to necessarily recognize the abstract idea of morality because there would be no interactions possible with other psychological beings (animals) since they are the only one. That doesn't make it eternal though... You assumed I was talking about that.
You've blogged about "Good" and "Evil" before and this post tied in to it. In this post, you say that "Ka is a moral essence" with a "moral potential" that we can develop to become better people.
Good and Evil are useful concepts but they tend to be based on what a person or group values.
Lately we've heard a lot about the values of Freedom and Equality. We've also heard new definitions of those values like Freedom means the Freedom to force your sexual fetishes on others or kill your unborn child. Equality means that everyone must have the same outcomes or someone somewhere is an evil racist. These weren't the intended definitions of the people who wrote our Constitution and yet they have been skewed into this new bizarre self-destructive "morality" based on nihilism or complete ill-regard for human nature and reality itself.
A lot of animal behavior is instinctive. I'm not sure that humans are that different. Our morality in the past was based on survival of groups or tribes. As populations grow and individuals are more able to get along without belonging to groups or tribes, new moralities may be necessary.