system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 why do we have bones around almost all places but not around our tummy?
gpt
Bones provide *stability*; muscles and similar tissue provide *mobility*. The belly needs more mobility, both for things like digestion, pregnancy and breathing, and for things like the range of movement our torso is capable of (bending, turning, lifting, etc). With too many bones in the torso, these essential activities would be much more difficult. 

Your abdominal wall is 4 layered sets of muscles and lots of cool related tissues, giving some containment and structure as well as the capacity for all those actions. Bodies are amazing! 💚