[rojobuffalo]

Good point about corvids. Ants are another example I was thinking about. They actually do engineer ecology on the scale of individual mounds by feeding and growing fungi that they eat. They are spread all over the Earth, and I think they have us beat in terms of biomass. Maybe there could be another definition for a weaker form of intelligence that covers those cases.

[SAI_Peregrinus]

Ants are especially interesting. Each individual is very simple, you could probably create an accurate ant model with a (very big) finite state machine. Yet entire colonies are extremely complex. I suspect that it's analogous to human brain cells vs the entire brain. Each cell isn't intelligent alone, but the whole is.