Form appears to be a property 
capable of eliciting or 
"releasing" instinctual 
reactions in other species as 
well. For example, herring-gull 
chicks, on the day after 
hatching, will "beg" far more 
frequently at a model whose 
shape resembles the bill of the 
parent than at models of other 
shapes. No such preference 
could be manifested unless the 
capability of form perception 
itself was present from birth.

    Human infants also show 
preferences with respect to 
what shapes they will look at 
during extended periods of 
observation. To discover such 
preferences, psychologists 
monitor the direction of the 
infant’s gaze. The object at 
which the infant looks is 
reflected off the cornea over 
the pupil of the eye. The 
experimenter can simply clock 
the amount of time spent 
looking at one thing or another 
or, better yet, can record the 
session on film or videotape 
and analyze it later. In recent 
research, the infant’s eye 
movements are accurately 
determined by an apparatus 
that tracks the eyes.