lightning bugs

fireflies in a tree at night.
10 seconds, Lampyridae display. They are hanging out in a quercus palustris.
They don't hang out in the tulip tree to the right.
This chemically-produced light from the lower abdomen may be yellow, green, or pale red — wavelengths from 510 to 670 nanometers. Most fireflies are quite distasteful and sometimes poisonous to vertebrate predators.--Wikipedia