Why is there a ribcage around heart and lungs, but only a muscular wall around stomach and intestines?

Question

Why is there a ribcage around heart and lungs, but only a muscular wall around stomach and intestines?

Answer 1

Not to mention that some of the muscles required for breathing need the rigidity of the ribcage to function properly.

Answer 2

if you had a ribcage all the way down your stomach and intestines your flexibility and mobility would be greatly limited. there is a compromise between flexibility and protection the way we have our ribcage.

Answer 3

Because you can live without pieces of your intestine, you only need one kidney, you can also live without pieces of your stomach. But you can not live without your heart or lungs. Therefore you need ribs to protect those extremely vital organs. Hope that helped.