Parkour Athlete Swaying a Model Tree (video) Society for Experimental Biology Loading video... Caption Standing in for an orangutan, a parkour athlete sways and jumps from a model tree. Researchers measured his energy expenditure during this and other activities to gain insights into why orangutans spend so much time up in the trees. Credit SRL Coward and LG Halsey Usage Restrictions None 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.