Intense nocturnal warming alters growth strategies, coloration, and parasite load in a diurnal lizard

1. In the past decades, nocturnal temperatures have been playing a disproportionate role in the global warming of the planet. Yet, they remain a neglected factor in studies assessing the impact of global warming on natural populations. In ectotherms, physiological performance is influenced by thermal conditions and an increase in body temperature of a few degrees during night-time is sufficient to induce a disproportionate increase in metabolic expenditure.

2. Here, we question whether an intense augmentation of nocturnal temperatures is beneficial or deleterious to ectotherms. Warmer nights may expand a species thermal niche and open new opportunities for prolonged activities and improve foraging efficiency. However, increased activity may also have deleterious effects on energy balance if exposure to warmer nights reduces resting periods and elevates resting metabolic rate.

3. We assessed whether warmer nights affected an individual’s growth, dorsal skin colouration, thermoregul...