Elephants have the most blood of the animals referenced, possessing approximately 245 liters.
Let's compare the blood volumes of the animals mentioned to understand the differences better:
- Mice: Approximately 0.0016 liters
- Humans: Approximately 5 liters
- Cows: Approximately 39 liters
- Elephants: Approximately 245 liters
Clearly, the elephant holds the largest blood volume among this group. Body size is a major factor influencing blood volume; larger animals require more blood to support their larger circulatory systems and overall metabolic needs.