Previous looking time studies have shown that infants use the heads of cat and dog images to form category representations for these animal classes. The present research used an eye-tracking procedure to determine the time course of attention to the head and whether it reflects a preexisting bias or online learning. Six- to 7-month-olds were familiarized with cats or dogs in upright or inverted orientations and then tested with a novel cat and novel dog in the same orientation. In the upright orientation, infants fixated head over body throughout familiarization; with inversion, no head preference was observed. These findings suggest that infant reliance on the head to categorize cats versus dogs results from a bias that pushes attention to the head.