By CLIVE THOMPSON Illustrations by TATSURO KIUCHI MARCH 6, 2018 The spectacle of human bodies on an ice track, hurtling headfirst at speeds of up to 90 m.p.h., can make skeleton unsettling enough ...

The human skeletal system is not quite as simple as the popular children's song suggests. The "head bone" (actually made up of 22 separate bones) is not connected to the "neck bone," but rather to ...