Those ancient teeth and the endurance predator: Dentition and human heat adaptation

Human thermoregulation is characterised by the ability to sustain endurance activities in hot environments through sweating and efficient heat dissipation. Combined with habitual bipedality, these adaptations enabled persistence hunting, where prey animals, constrained by panting, succumbed to hyperthermia during prolonged pursuit. This strategy offered early Homo access to calorie-dense animal foods, but it also imposed the critical requirement to consume prey rapidly under thermally stressful conditions. We argue that dentition was a key, though often overlooked, enabler of this thermoregulatory foraging niche. Fossil evidence demonstrates reductions in canine size, the disappearance of the honing complex, and modifications to molars and enamel thickness that enhanced versatility and durability in food processing. Teeth acted in concert with emerging tool use to minimise mastication time, reduce heat production, and accelerate nutrient intake. Alongside changes in gut morphology and microbiome composition, dentition formed part of an integrated system that linked diet, thermoregulation, and survival. Viewed in this light, dental evolution was not merely a dietary adaptation but a central contributor to Homo's ecological success as an endurance-adapted omnivore. We frame our hypothesis on heat and handling time: in hot-dry contexts, versatile human dentition together with stone tools and cooperation helped compress the post-kill processing, reducing on-site heat and dehydration; we avoid teleological 'optimization' and emphasize mosaic, trade-off responses.