Let me elaborate, how likely is that there’s an animal on earth that’s smarter than us? By smarter, I understand intelligence is a nuanced topic unique to different animals, so for the sake of argument, let’s talk about, mathematics, critical thinking about where and how to apply those mathematical concepts, and creativity in any form.
The likelihood of that is a statistical zero.
Intelligent civilisations leave traces. We’ve found none that would indicate another species that would have the potential of rivaling us
What if they don’t have hands and live in the ocean?
The question was more intelligent that us in applied mathematics and critical thinking. Dolphins, whales, orcas have all been well studied. And while they are in the top 0.01% of intelligent life on earth. They are on average not smarter than humans. Though I can not speak for the below average humans.