Pigeon
Upper Body Cavity

Pigeon
Lower Body Cavity

Comparison of Vertebrate Hearts

Vertical Cross Section showing ventricles and atria

Amphibian frog
Avian pigeon
Mammalian rat

Comparison of Vertebrate Digestive Systems

Amphibian frog l.outer Stomach r. inner stomach, note folds and beetle remains near top
Avian pigeon Gizzard Note stones for grinding and thick muscular wall
Mammalian rat stomach moved downward from under liver (top)