Rogers found that a chick's lateralisation depends on whether it is exposed to light before hatching from its egg—if it is kept in the dark during this period, neither hemisphere becomes dominant.

罗杰斯发现，小鸡的偏侧性取决于它在孵出蛋之前是否暴露在阳光下——如果在这段时间里保持黑暗，右脑或左脑都不会占优势。