The idea that animals are not conscious comes from religion, not science.

The only conscious entity that I’m 100% positive exists is myself. If you reject solipsism, none of the traditional criteria that tell apart humans from animals (e.g. language or ethics) hold up to scientific scrutiny as far as consciousness is concerned.

The criteria that have been scientifically vetted (based on information theory among others) also hold for animals and other living beings (genes known as transcription factors form network that are isomorphic in form and function to neuronal circuits).