Those are very good questions. First, I was distinguishing between multiple types of intelligence, rather than ranking them. However, there are several aspects of human intelligence that we’d probably be justified in saying something like “By these metrics, humans are more intelligent than any other species on the planet.” Those include the sophistication of technology, the amount and complexity of of information exchanged between persons, the ability to learn, and so on. Other animals can learn through accident or experimentation and adopt a new behavior. Some even exhibit social learning, as when a troop of baboons learned to wash their food by observing the matriarch, who had discovered it on her own. Most other species have languages, whether vocal, visual, or chemical. But most learning occurs over evolutionary time rather than at the individual level, and most of those languages are fairly hard coded.

The answer is definitely yes for the second question, with the eusocial animals like ants and bees being the obvious examples. The queen is not the “brain” of the colony. She is more like the reproductive organ. The brain emerges from of all the ants collectively interacting with each other and the environment. I agree with EO Wilson that humans are also eusocial, and so by extension carry out collective computation - information processing and learning - at the social level using what we might think of as an emergent brain layered on top of your individual brains.