Other problems with the human supremacy myth

I prefer to say that a lion doesnt need morality or laws--its behavior is already governed by instinct and a modest temperament. You never see lions or other carnivores engaging in bloodsport or making a spectator sport out of what they need to do to survive. To say that a lion needs to be able to understand human laws is like expecting a blind man to be able to read a newspaper or a man with no arms to be able to juggle.
Who said moral regard needs to be reciprocal? As noted, it isnt the case for the mentally disabled.

But then you get into the real issue, which is the myth that humans as a group are superior in value to all other life. This myth has no basis in fact, because all the criteria used to claim this(from dna, to scripture, to mental ability) are based upon subjective conditions conveniently determined by those who stand to benefit from the discrimination. Human supremacy would need to be an objective fact--something Nature or the universe demonstrates in every day life(like humans being immune to gravity or spared from being burned by volcanic eruptions).
Humans are just as mortal as any other species, so the claim of superiority is dubious.

But for the human supremacist, the biggest problem is that they want to have their cake and eat it. They want to say that it is ok to discriminate on the basis of species, but not on the basis of race, gender, age, wealth, religion etc--which humans have been doing since the beginning of recorded history despite all the laws in place to stifle such behavior. So the claim that humans are superior as a species is undermined by the fact that humans prey on each other. You cant make a good case against racial supremacy when you are advocating the very same type of flawed ethical belief(and it should be noted that other species dont adhere to speciesism--a lion doesnt say it has a right to kill a gazelle but no one has a right to kill it..the burden of adhering to moral laws falls on human shoulders since they are the ones that require moral laws to govern their behavior. Other species do not).

Ultimately, the issue isnt so much whether humans are superior to other life, but how they can reconcile that myth with the fact that much of the criteria they use to suggest human superiority falls apart under scrutiny.
Humans are irrational, humans are sadistic(and take pleasure from knowing they cause suffering to others), humans are greedy, humans are self destructive, humans are arrogant. Its hard to find any of those characteristics as being observable in the natural world, even though human language tries to reinforce the myth(i.e. to be humane is to be kind and good, to be inhumane or non human is to be evil). Other species have exhibited altruism however, and much of the type of altruistic behavior that humans do is actually damage control-attempts to fix problems created by human activity so defining it as pure altruism is problematic as well. Ironically, i is much easier to show human inferiority than superiority, based on the very criteria humans use to suggest supremacy.