How cells grow differently from their neighbors: How noise becomes a symphony

In both living and non-living systems, it is widely observed that ordered behaviors emerge through noisy and nonlinear interactions among their components. In living organisms, in particular, highly reproducible, robust cell states and cell types, tissue-scale patterns, and organ shapes arise despite stochastic gene expression, heterogeneous cell growth, and environmental fluctuations. If life builds order from heterogeneity while never completely eliminating it, is heterogeneity merely a byproduct or could it be part of the means by which biological order is generated? In plant development, heterogeneous cell growth is a default arising from both noise (irregular biological fluctuation) and differential signals. Recent studies have investigated a variety of types of heterogeneity and illuminated how they shape morphogenesis. Here, we define and review the concept of heterogeneity. Then, we describe possible origins of cell growth heterogeneity. Finally, we show how plants use or buffer heterogeneity to pattern cell types and build robust and environmentally adaptable organs. We posit that to be robust or to reshape and adapt to the environment, biological systems tune heterogeneity.