Nature’s design can seem random upon first glance; however, a closer look reveals a common pattern that ties it all together, from the growth of a tree bark to the toss of a coin — the bell curve.

Two basic principles are involved, the idea of exponential growth and its ultimate control. The basics of population ecology emerge from some of the most elementary considerations of biological facts.

Researchers from the University of Freiburg have identified the HAN molecule as an important regulator that controls plant ...