Consciousness is not a well-scoped object of scientific investigation. It doesn't have a definition or characterization based on observable things or behavior. If I were a natural scientist, I wouldn't take a bet that I can scientifically explain a phenomenon which I can't even describe in terms of observable things.
Conscious experience is an observable thing, meaning that we can subjectively experience it and infer its existence in other sentient beings (including in cows and pigs), and it is part of nature. The problem is, we still have no good idea how it comes to be.