Face-to-face with a predator, you don't need your digestive system, or your libido, or your immune system, because if you're body is expending metabolism on those things and you don't react quickly, you might become the lion's lunch, and then none of those things matter.
Akis į akį su grobuonimi tau nereikia virškinimo sistemos, ar libido, ar imuminės sistemos, nes jei kūnas šiems dalykams  eikvos savo metabolizmą ir nereaguosi greitai, gali likti liūto pietumis,  ir tada visa tai nebereikalinga.