The French word conscience covers the semantic ranges of English "conscience," "consciousness" and "awareness". Maybe that's one reason why I tend to think all those notions are closely connected.
Between us and (other) animals -- the topic and the ensuing discussion on "social conditioning" is strongly reminiscent of Pavlov's dog, a famous case of human-educated animal "conscience" -- there is both continuity and difference. The major breakthrough, I feel, is human language (or symbolism),through which we have developed an unprecedented imaginary representation of "self," including continuity in time (memory and future projection). On the mirror of language we watch ourselves and judge ourselves as we speak and act. The endless splitting (the watcher watching the watcher watching, ad lib.) makes homo sapiens a self-conscious animal. Science is con-science, as soon as we can say "I". Moral conscience (including guilt or self-satisfaction) is just one aspect of that basic process imo.