if an organ digests food then the food must pass through that organ
digestive_system has esophagus_and_stomach turkey is food. health_food is food. bird_digestive_tract is body_part. mammal_digestive_tract is body_part. digestive_system has do_with_food digestive_tract is organ_system. digestive_tract is body_part. all_animals has digestive_system bird_digestive_tract is digestive_tract.