Relationships between animals (including people) in nature can usually be classed as symbiotic, parasitic, or predatory. Altruism is an evolutionarily new and interesting one!
I'm arguing that evolution sees that symbiosis is utilitarian & motivates the individual to engage in this with a feeling of altruism, just as evolution sees sex as utilitarian & motivates the individual with lust. Is lust sometimes wasted (homo, fap, etc.?) yes c.f. "altruism"