Little by little, science is coming closer to understanding emotion as the universal operating system of animal consciousness. In this study,
various species of animals are found to respond to the distress calls of other species' infants. This is because an infant no matter the species is an emotional ground, a preyful essence. Similarly, when an animal is in distress, it is emitting prey energy, i.e. vulnerability. It is broadcasting that it can absorb and conduct another being's Drive and this draws others toward it, emotion running from predator to prey is the universal base line of code, this is the case whether one is looking at an infant, a paramour, or a defenseless prey. It's a thermodynamic principle, the very architecture of the animal mind, a universal principle of attraction. Now because an infant can manifest a predatory aspect pronounced enough to reflect the projection of emotion back to the adult, then a caregiving urge and species-specific suite of reflexes becomes available to the adult. Care giving follows from prey-making because the oldest relationship between sentient beings is the predator/prey dynamic, not the parent/offspring one, and evolutionarily the latter must follow from the former.
Emotion is thermodynamic, it moves from high to low pressure, which behaviorally translates from predator to prey, this is consistent across the animal bandwidth no matter the context, it is a principle of conductivity.