A hot cup of tea, coffee or cocoa is calming and comforting—but how can holding a warm mug affect our emotions? In Heartwarming, social psychologist Hans Rocha IJzerman explores temperature through the long lens of evolution. Besides breathing, regulating body temperature is one of the fundamental tasks for any animal. Like huddling penguins, we humans have long relied on each other to maintain our temperatures; over millennia, this instinct for thermoregulation has shaped our lives and culture.

As IJzerman illuminates how temperature affects human sociality, he examines fascinating new questions: How will climate change impact society? Why are some chronically cold and others overheated? Can thermoregulation keep relationships closer, even across distance? The answers offer new insights for all of us who want to better understand our bodies, our minds and each other. Heartwarming takes readers on an engaging journey through the world, seen from the perspective of coldness and warmth.