I simply wish my parents would have taught me about speciesism and how it was just as evil as racism, sexism and heterosexism. Sadly, my parents were lied to by their parents who were lied to by their parents and so on.
Speciesism is morally objectionable because, like racism, sexism, and heterosexism, it links personhood with an irrelevant criterion. Those who reject speciesism are committed to rejecting racism, sexism, heterosexism, and other forms of discrimination as well.