There's an incredible blind spot which makes humans think of intelligence and sentience as individual.

It isn't. It isn't even individual among humans.

We're colony organisms individually, and we're a colony organism collectively. We're physically embedded in a complex ecosystem, and we can't survive without it.

We're emotionally and intellectually embedded in analogous ecosystems to the point where depriving a human of external contact with the natural world and other humans is considered a form of torture, and typically causes a mental breakdown.

Colony organisms are the norm, not the exception. But we're trapped inside our own skulls and either experience the systems around us very indirectly, or not at all.