Definition from Webster.com
Main Entry: 1soul
Pronunciation: 'sOl
Function: noun
Etymology: Middle English soule, from Old English sAwol; akin to Old High German sEula soul
1 : the immaterial essence, animating principle, or actuating cause of an individual life
2 a : the spiritual principle embodied in human beings, all rational and spiritual beings, or the universe b capitalized, Christian Science : GOD 1b
3 : a person's total self
4 a : an active or essential part b : a moving spirit : LEADER
5 a : the moral and emotional nature of human beings b : the quality that arouses emotion and sentiment c : spiritual or moral force : FERVOR
6 : PERSON <not a soul in sight>
7 : PERSONIFICATION <she is the soul of integrity>
8 a : a strong positive feeling (as of intense sensitivity and emotional fervor) conveyed especially by black American performers b : NEGRITUDE c : SOUL MUSIC d : SOUL FOOD e : SOUL BROTHER
... Answers ...
Definition 1: perhaps
Definition 2: No, this is the real world not fantasyland. There are no "souls"
Definition 3: No, other species are not humans
Definition 4: Yes, there are moving parts or essential parts for all species, remove the brain and the beast dies, thus the brain is essential.
Definition 5: Brain chemistry likely cause of human "soul" here, many species of animals have brains, so likely that some species will also be a yes here.
Definition 6: nope
Definition 7: Some animals can be personified
Definition 8: Some animals become soul food