Experimental Apparatus (IMAGE) Cell Press Caption (A) Tool laterality probing apparatus and tool. Note the perpendicular placement of the tool to prevent approach bias. (B) Eye-dominance apparatus. (C) Right-sided tool use by Mango, viewed from above. (D) A right-eye ''look,'' with eye placed directly to the hole, by Liane, viewed from above. Credit Current Biology, Martinho III et al. Usage Restrictions Credit Required License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.