Final answer:
The animal with a heart-shaped right kidney is the horse. Horses exemplify internal organ asymmetry, a common characteristic among animals where organs are not symmetrically shaped or positioned.
Step-by-step explanation:
The question, "Which animal has a heart-shaped right kidney?" pertains to the anatomy of certain animals. Upon examining the list provided, which includes various mammals such as rabbits, horses, and monkeys, we can identify that the animal with a known peculiarity in kidney shape is the horse. Horses have an interesting anatomical feature where their right kidney is indeed heart-shaped, unlike their left kidney which is more typically bean-shaped like in most mammals.
It's important to note that internal organ asymmetry is common in animals. While external symmetry can often be observed, internal organs like the heart and liver tend to have an asymmetric position or shape within the body. Understanding these anatomical details is critical for veterinary practice and biology studies.