An atheist has defined morality as "agreed behavior in a community."
I responded, "If we came from animals who have existed and evolved over 2 billion years, then nothing in evolution "requires" agreement. A cat can climb a tree or avoid a tree, neither is right or wrong, neither is required. You cannot praise conformity nor shame non-conformity. Even praise and shame are decisions that are meaningless like having wings or not having wings. If an animal or human derived from animals has no shame, it is irrelevant as an animal having no wings. No trait is mandatory, required, or essential. Even survival is not mandatory, required or essential. Plenty of species are extinct and that is just fine. There are no goals and no purpose or objective in the outcome of an explosion."