Two males red-eyed tree frogs
square off over a female. Fisticuffs will soon ensue and as a final challenge to each other, the males... er... vigorously shake their bums at each other. Their quivering buttocks shake the plants they sit on, sending threatening vibrations towards their rival. This secret line of communication has just been uncovered by Michael Caldwell
from Boston University. To decipher these messages, he has used a hi-tech combination of infrared cameras, saplings rigged with accelerometers and even a cybernetic Robofrog. During mating season, male red-eyed tree frogs gather in the rainforests of Panama to compete for females with dramatic multimedia performances, involving calls and visual signals. Studying these messages can be difficult because the frogs communicate at night. A white lamp would kill their natural behaviour, prompting males to become far more restrained than usual, save in the presence of females. Instead, Caldwell watched them under ...
