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Content with tag solar radiation .

Solar and terrestrial radiations explain continental-scale variation in bird pigmentation

Animals living on the earth's surface are protected from the damaging effects of solar ultraviolet (UV) radiation by melanin pigments that color their integument. UV levels that reach the earth's surface vary spatially, but the role of UV exposure in shaping clinal variations in animal pigmentation has never been tested.

Avian eggshells coping with solar radiation

Solar radiation is an important driver of animal coloration, not only because of the effects of coloration on body temperature but also because coloration may protect from the deleterious effects of UV radiation. Indeed, dark coloration may protect from UV, but may increase the risk of overheating. In addition, the effect of coloration on thermoregulation should change with egg size, as smaller eggs have higher surface?volume ratios and greater convective coefficients than larger eggs, so...

Why do kestrels soar?

Individuals allocate considerable amounts of energy to movement, which ultimately affects their ability to survive and reproduce. Birds fly by flapping their wings, which is dependent on the chemical energy produced by muscle work, or use soaring-gliding flight, in which chemical energy is replaced with energy harvested from moving air masses. Flapping flight requires more energy than soaring-gliding flight, and this difference in the use of energy increases with body mass. However,...