Egg, larva, pupa and adult
Answer:
Reproductive System
All the body systems have one role or the other to play in digestion and absorption. Even the excretory system removes waste and toxins from the body, leaving the useful materials.
However, the reproductive system is not actively involved in digestion.
Answer:
The genetic variations that are best suited for their enviornment
Explanation:
Those that are not well suited for their environment will die off, leaving only the ones that are suited for it. This species will slowly take hold until the species has adapted and become a completely different one.
Forceps, they literally are almost the exact same thing.