Where do hiccups come from?

Hiccups are caused by involuntary contractions of your diaphragm — the muscle that separates your chest from your abdomen and plays an important role in breathing. This involuntary contraction causes your vocal cords to close very briefly, which produces the characteristic sound of a hiccup

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.