There are several animal species (hominid apes, elephants, and some cetaceans, for example), that we know have self-awareness, empathy, theory of mind, can reflect on their own thoughts and decisions, and show altrustic behaviour that goes beyond the tit for tat principle. They have deep relationships, often with animals that are not even of their own species (including but not limited to, humans). They have cultural traditions (learned behaviours transmitted transgenerationally within communities) and understand symbolism.
Often these animals show great interest for issues which do not, usually, concern animals. Chimpanzees have been reported to have proto-ritualistic behaviour in maintaining shrine-like structures with no directly apparent purpose, and elephants are very well known for their strange (but for a human, quite easy to understand) behaviour around the physical remains of their conspecifics.
In the aforementioned species, it has been experimentally demonstrated that these animals have an understanding of fairness and lies.
Some theologians propose the idea, based on the above findings, that some non-human animals (namely great apes, in the articles I brought as example) are moral agents, and that humans misinterpret the specialness of Imago Dei for exclusiveness. They argue, that most interpretations of Imago Dei are not aimed at genetics or physiology, but other traits, like actions or thoughts. There seems to be sufficient evidence that some animal species qualify for such interpretations, and consequentially, they should be understood as part of Imago Dei.
As someone who has worked with and studied animals for a long time, I think if I were a christian, I would find these arguments extremely compelling. At least, there have been some animals during my life, whom I have thought of, for all intents and purposes, as a person, because I was firmly convinced, that persons they were (and I didn't even like some of those persons ).
Can you identify with this, Christians, or do you find the thought abhorring / ridiculous? If so, why? What would be the implications of such an interpretation in your opinion?