Some plants like it hot. Cotton with superior heat tolerance can be a profitable crop for warmer climates, so scientists are identifying tolerance-specific genetic selection tools to assist breeding efforts. Unfortunately, it’s nearly impossible to differentiate between heat tolerance and heat avoidance simply by examining the quantity and quality of final crop yields. Heat avoidance refers to characteristics that enable a plant to withstand the heat with similar, but less reliable, results–for example, by shifting the bulk of metabolic activity to cooler, evening periods.