How comparative anatomy provides insight into human anatomy

Abstract

Human anatomy instructors in the United States have remarkably varied backgrounds for an academic discipline; we work alongside those trained at every scale of biological organization, from molecular genetics to ecology, and these different training regimens provide anatomy departments with a variety of strengths. In this talk, I outline and detail how comparative whole organism anatomy can be useful in teaching human anatomy, primarily in the context of traditional lectures (at both the undergraduate and graduate levels) through three broad categories. First, understanding how relatively anatomically more complex animals like humans develop embryologically is facilitated by appreciating the anatomy of relatively simpler animals like platyhelminth and annelid worms; furthermore, some developmental defects are better understood through the lens of evo‐devo (i.e., normal conditions in other animals are sometimes abnormal conditions in humans, like syndactyly in bats). Second, comparative functional biomechanics yields insight into normal and abnormal musculoskeletal function. The trade‐offs between joint stability or flexibility, or power arm ratios for power or speed, are well‐illustrated by extreme morphology of homologous structures in other animals, such as the incredibly speedy ankles of cheetahs compared to the relatively powerful ankles of humans. Third, much of any scientific professional's development relies upon mastery of Greek‐ and Latin‐derived vocabulary; genus and species names of animals can help anatomy students better remember structural terms. For example, Pterodactylus was a remarkable genus of flying reptiles, and understanding the etymology of the Greek words “pteron” (wing) and “dactyl” (finger) helps students appreciate how the sphenoid bone's pterygoid process and the pterygoid muscles are wing‐shaped, and the clinical conditions syndactyly and polydactyly refer to webbed or conjoined fingers and extra fingers, respectively.Application of human anatomy knowledge by physicians to animals gave rise to the field of comparative anatomy in the 1600s; Edward Tyson, a human physician, recognized chimpanzees were more like humans than monkeys, and porpoises were more like land mammals than fish from detailed comparative gross dissections. These observations of patterns in the anatomy of humans and animals contributed to Darwin and Wallace independently developing the theory of evolution, which underpins the national One Health initiative. Recognizing humanity's shared ancestry with animals ensures a measure of shared descendance in the instruction of human and animal anatomical education.Support or Funding InformationThis work was supported by the American Association of Anatomists and the Arkansas College of Osteopathic Medicine.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.