Animal Souls?

It's possible that spiders dream. Also octopuses and some birds and fish:

If Animal Dreams Imply Sentience

This article proposes (following the example of WHEN ANIMALS DREAM, a recent book by David Peña-Guzmán) that dreaming suggests an animal is sentient, "a unique individual who experiences life and processes it via thoughts and feelings." The article mentions multiple examples of animals that appear to display emotions and mental states such as joy, sorrow, empathy, gratitude, friendship, loneliness, and self-awareness. Many creatures have been observed coming to the aid of other members of their species, even at personal risk to themselves. The authors of the article go further and propose, "If a creature can feel and express feeling. . . then it is entirely possible that it is a spiritual being."

Clearly, they're using the term "spirituality" more broadly than most people do. For these authors, it seems the capacity for self-awareness, emotion, and response to other living beings constitutes spirituality. The article also suggests animals have souls. By this term, the writers don't mean "soul" as an incorporeal part of the personality that survives death. In fact, they state explicitly that they aren't asserting anything specifically religious. "The stronger capability a given species has for fellow feeling, the more likely it is that members of that species have perceptions we would recognize as spiritual. . . . The ability to emote is, in our estimation, a nascent form of soul." They're advancing a "biophilia view that many sorts of creatures share a connected sentience" on our planet.

Classically, Aristotle propounded a similarly broad definition of "soul" as "intrinsic principles of animal and vegetable life." All living things have souls, in ascending orders of complexity. The vegetative or nutritive soul contains the elements of growth, nutrition, and reproduction. The sensitive soul has the powers of sensation, emotion, and desire. The highest, the rational soul, constitutes the capacity for reason. Plants have only vegetative souls. Animals have both vegetative and sensitive souls. Human beings, in addition, have rational souls. This essay from the online ENCYCLOPEDIA BRITANNICA explains the concept in more detail:

Aristotle's Philosophy of Mind

Contrary to the view of animal cognition prevalent until only a few decades ago, contemporary biologists seem to be discovering more and more evidence that "lower" life forms exist on a continuum with us, not separated by a sharp line.

Margaret L. Carter

Carter's Crypt