Intelligence is a term too vague to be of use for the comparison of species. If you were tasked with finding the next waterhole in an arid landscape you might not be found very intelligent compared with a whole range of other species. Or if the proof of intelligence was to manage a planet in a sustainable way.

Rights are difficult. Basically we have, gradually, invaded a lot of spaces once occupied by other species, and keep invading more. Giving rights to dogs, cats, whales or horses is an invader giving rights to the invaded. On the other hand, as we keep turning the temperature of the planet up, we worsen the conditions for ourselves and some bug, fungus, microbe or lizard might prove to be the next big thing after mammals had their chance?