Butterflies are self propelled flowers.
— R.H. Heinlein
Summer might be ebbing, but butterflies, like this Painted Lady resting on a piece of wood, are colorful reminders that autumn isn’t quite due.
Wondering about this behavior, I found the following explanation for basking on the University of Kentucky’s Web site (Dept. of Horticulture):
Butterflies are cold-blooded, meaning they cannot regulate their own body temperature. As a result, their body temperature changes with the temperature of their surroundings. If they get too cold, they are unable to fly and must warm up their muscles in order to resume flight. Butterflies can fly as long as the air is between 60°-108° F, although temperatures between 82°-100° F are best. If the temperature drops too low, they may seek a light colored rock, sand or a leaf in a sunny spot and bask. Butterflies bask with their wings spread out in order to soak up the sun’s heat.