'"on what grounds to you assert that all other non-human beings...

'"on what grounds to you assert that all other non-human beings are less worthy of respect than humans?"

On the grounds that I'm not a believer in Darwinism and therefore understand that humans are not the moral equivalent of animals.'

we are still in some sort of 'age of excuses'.

Something that will take another 50-100 years to pass. Assuming theres that much time.