That's not the conclusion: no one is claiming "as smart as humans". Intelligence is multidimensional, and along some dimensions animals outperform us by a long shot.
Some birds remember thousands of locations of their stashed food. Some animals have a detailed internal map of many square miles of land on which they live. Pick just about anything a typical 3 year old can do, and we can find an animal to outperform them in that respect.
Are We Smart Enough to Know How Smart Animals Are?
https://www.amazon.com/Are-Smart-Enough-Know-Animals/dp/0393...