To get back to the thread topic, I would say that fiction has given us great examples of what nature could produce if God were willing.
The sentient Ents of Lord of the Rings come to mind, how their slow and methodical speech wins the day for deliberate action.
Where could I start with the Chronicles of Narnia? From the helpful little mice who chew away Aslan’s bonds on the Stone Table, to the noble Centaur warriors who defend Him in battle, to the… adorable Reepicheep who gains Heaven in a little kayak, the animal kingdom is accorded a nobility here that may not otherwise be evident.
I think Babylon 5 has some fascinating concepts of sentience. The Minbari believe that the Universe is sentient in itself–not an uncommon human belief. Humans themselves evolve into beings of light and energy after millions of years. The Vorlons and the Shadows provide two opposing views of “ancient aliens” who have marvelous features: the Vorlons are beings of light cloaked in ordinary “encounter suits” and they fashion living vessels not unlike squids. The Shadows are invisible on human light spectra and also employ biotechnology, even to enslave humans in psionic traps.
To stray even further from a Catholic viewpoint, I give you the Neanderthals of Robert J. Sawyer’s Neanderthal Parallax. They arose during a polar magnetic shift, when Homo sapiens lost the ability to reason. They have a unique structure for living, a “hub and spoke” habitat where the males live on the outskirts in homosexual relationships, and only join the females “when Two become One”. They have implanted themselves with Companion devices which are more or less permanent mobile phones. And their cultures clash when they come into contact with humans via a parallel universe portal.