Final answer:
Per Scholander was a pioneering physiologist who researched diving mechanisms, how warm-blooded animals cope with cold environments, and fish swim bladder functions, contributing significantly to the field of comparative physiology.
Step-by-step explanation:
Per Scholander was one of the first physiologists who conducted in-depth research into various physiological adaptations in organisms. His work included the study of diving mechanisms in marine mammals, how warm-blooded animals respond to cold environments, and the function of fish swim bladders. These areas of study are crucial to our understanding of how animals have adapted to their environments to survive and thrive. For instance, Scholander explored how whales maintain their body temperature in cold waters through a mechanism known as a countercurrent heat exchanger, a concept that has parallels with the ways land animals, like those bearing thick fur or entering hibernation, manage heat retention.