But the royal would not accept that this shift in attitudes meant it was possible for animals to ever have rights.
"Today we are always hearing about animal rights," she said. "I'm a great animal lover and I'm involved in a lot of conservation, but animals don't have rights. They don't have bank accounts. They don't vote.
"We have obligation. We have obligation to animals, but to say they have rights? They don't have rights. You only have rights if you pay your taxes. You earn your rights."
Animal campaign group PETA branded her comments "daft" and said they reflected "ignorance of the issue."
The organisation insisted people are now "waking up to the view" that legal rights should not be determined by species.
Princess Michael was at pains to stress her love for animals, telling the audience that she has adopted unwanted pets and had the word "cats" added into the title of Battersea Dogs and Cats Home after her husband was made patron.
She also spoke of how she helped rear a cheetah cub in Africa after its mother was shot. But this is not the first time the Princess has irked animal rights campaigners. She reportedly owns 14 fur coats and after she was spotted wearing one in 2007 she was sent a faux fur version by PETA.
She has also spoken out about urban foxes. The royal once revealed she "unashamedly hates" the creatures after they destroyed her collection of bantam hens.
"I sometimes see them sitting on the drive [at Kensington Palace] and I shout, "tally ho!" very loudly," she said. "But they pay me no attention."
PETA's Elisa Allen said: "PETA urges Princess Michael to study the subject, rather than making an off-the-cuff statement that reflects ignorance of the issue... her daft assessment would mean that children and certain classes of human beings are also not entitled to rights.
"Our understanding of who is deserving of "rights" has, of course, progressed... people are waking up to the view that legal rights should not be determined by your species any more than by your gender, age or skin colour.
"Princess Michael would do well to remember that our society has changed... people will look back on our treatment of these animals with shame, as many of us already do."
- Daily Mail