I think the most involved would be your circular system because since your running fast you need to pump blood. Your muscular system because your moving a lot and your respiratory system because you need more oxygen
Answer:
Therapsids were "mammal-like" reptiles and are ancestors to the mammals, including humans, found today. One group of therapsids is called dicynodonts. All species of dicynodonts were herbivores (plant eaters) and their sizes ranged from small burrowers to large browsers.
Mammals evolved from a group of reptiles called the synapsids. These reptiles arose during the Pennsylvanian Period (310 to 275 million years ago). It was over millions of years that some of these therapsids would evolve many features that would later be associated with mammals.
<h2>
Please mark me as brainliest</h2>
I think it would be crust