Can I just say the Metroid life-cycle doesn't make any goddamn sense?
It starts out fine. Infant makes sense, Larva Makes sense, Alpha a little weird but I can see it. Gamma Okay now your pushing it but I'll let it slight because it at least looks like a more evolved version of Alpha.
Then Zeta comes along and Holy shit now their big dinosaur-bug things!? How does a floating jellyfish with teeth turn into fucking dinosaur!? Now granted real life has some crazy examples of metamorphosis during an animals life-cycle, like tadpoles and frogs.
But this is like if a tadpole turned into a dog with frog skin instead of fur!