Egypt, third millennium b.c. The Great Pyramid of Giza is both the oldest of the Seven Wonders and the only one still standing. Built by the pharaoh Khufu (reigned ca. 2551–2528 b.c.) to serve as his ...

A majestic row of five circular pyramids known as yácatas dominates a promontory overlooking Lake Pátzcuaro in the western Mexican state of Michoacán. Embodying the former might of the Purépecha ...

Pattern formation is the developmental process by which cells acquire different identities, depending on their relative spatial positions within the embryo. Pattern formation ensures that tissues and ...

A central pattern generator (CPG) is a neuronal network in which interconnected excitatory and inhibitory neurons produce an oscillating, rhythmic output in the absence of sensory feedback. CPGs play ...