Sign Stimuli
By Dave Hanks
Just looking at another animal does not stimulate a response. That which does stimulate is the result of signals. Signals can be changes in color, special body movements, special aromas, special sounds, and different positions of body parts. Tail position, or movement, is important to canines and Bison. Ear position is important to bears. Special smells and sounds are vital in courtship behavior, and movement can either be stimulating, submitting, or threatening. This is why a person must walk quietly, and not make any abrupt movements, when moving among either wild or domestic beasts - so as to not stir them up.
Colors are signals to lizards, fish, and birds. If an animal is colored, it can see color – not color blind like many mammals (who depend on light and dark shades). Many bird species utilize color, and because they are built differently than quadrupeds, crest feathers become important signal senders. Even if a species has no crest, the raising of feathers or wings become strong stimuli. Cardinals, Jays, Pyrrhuloxia, Phainopepla, and Titmice are some very notable birds with crest feathers.
The small Black-Crested Titmouse’s crest is certainly eye-catching and important in mate selection. Crests that are raised higher than usual, or forward, can indicate an aggressive mood – likewise the lowering of them can mean the opposite. Another sign stimuli of this bird is its alarm call. The alarm is a loud scold that fades away. Predators think that the prey has fled the scene and has given up the chase. The bird, however, is still nearby but hidden in a bush.
This songbird measures 5 ˝ to 6 inches at maturity. It loves to live wherever there is rampant tree growth, as they nest in tree cavities. In areas of urbanization, the Black-Crested Titmouse will also nest in telephone poles, fence posts, or man-made birdhouses. Urban shade trees, heavy timber, and deciduous forests may all be home to the Black-Crested Titmouse. It enjoys feeding on nuts, seeds, berries, spiders, insects and insect eggs.
(A Black-Crested Titmouse - Very alert, on a lichen covered branch)
|