The Shadow Bird
The shadow bird, Passer Umbra, is one of the lesser known representative of the finch genus. Due to its subtle camouflage, it has only been discovered recently, and a comprehensive study of its life-cycle and behavior has yet to be completed.
The shadow bird, as its name inidicates, is black in color, varying from light to dark depending on its surroundings. During cloudy days, it mostly stays hidden, coming out only when the sun is strong enough to cast the shadows in wich it can hide.
In addition to its color, the shadow bird can compress its own body, making it flat, and has special feathers on the left side that allow it to cling on to surfaces without moving, thus effectively apearing to be a shadow.
Although science has only recently discovered the animal, it is present in a lot of folklore, from Europe to Asia and Africa, and has inspired a number of popular stories. However, due to its furtive nature, it has always been considered more fairy-tale than reality. Until, in 1999, Dr. Anita Ombress, of the Institute of the Strange and Wonderful (ISW), managed to indisputably proove its existence by capturing one in her light-lab.
Papers have since abunded, but few have been published in peer-reviewed journals, because, no one knowing much about the bird, and it being very difficult to capture, few felt confident enough to be able to judge whether or not the papers had any real value, and experiments were in general not repeatable due to lack of subjects to experiment on.