Thinking about how this plays with Gurdjieff's[0] idea that I've been partial to lately that one is not born with, but instead must develop a soul through effort.
That's an interesting concept which aligns well with our vernacular use of the expressions "soulless" and "selling your soul." If a soul is sensitivity to others then that certainly has to be developed. The fact that it's poorly developed in many people (and even less so down the line of animals) is a good indicator that it might be learned or built-up evolutionarily in the species and the individual.