The open faces of sunflowers expressing warmth and happiness symbolize the sun. The face is actually hundreds, perhaps thousands, of tiny flowers arranged on a solitary inflorescence called a head ...

In storms or other turbulence, pilots need to know how the plane is orientated and the angle at which the plane is tilted toward Earth’s surface. If the plane’s nose is tilted downward at a 45-degree ...

Navigation requires a sense of direction (‘compass’), which in mammals is thought to be provided by head-direction cells, neurons that discharge when the animal’s head points to a specific azimuth.