behavior · environment · Nature

Movement study using Parkour athletes reveals orangutans’ climbing secrets

English: dave 59 took it myself at the Orang r...
Orangutan at the Orang rehabilitation centre, Buket Lawang ,Sumatra. (Photo credit: Wikipedia)

My M.A. thesis was on parkour, and how traceurs’ movement compared similarly to other primate movement behaviors, particularly the great apes. Now, a researcher in the U.K. has used traceurs to demonstrated how orangutans can move efficiently and effectively through the trees. Never would have thought of that, awesome!

From Io9:

Orangutans spend their lives swinging in trees and eating fruit… a fruit-based diet like the one orangutans prefer won’t provide much raw energy, while choosing to live up in the trees instead of padding about on the ground really should require a lot of it. To solve this apparent paradox, Dr. Lewis Halsey and his team at the University of Roehampton enlisted some expert practitioners of parkour to simulate orangutan movements in a controlled environment.

…According to the researchers, the orangutans’ secret is to use the natural moment of the trees to keep their own energy costs down. Here the primates’ extra mass is actually a benefit, allowing them to make their tree sway back and forth until it’s close enough to the next tree to move on. It’s not necessarily going to be the quickest way to move about, but it is energy-efficient, saving about 90% of the energy it would take to climb down one tree and up the next one.

It’s also considerably safer than going to the ground — as the researchers point out, the orangutans of Sumatra share their environment with tigers, which means any time spent out of the trees is time spent courting death.

From the BBC:

The results could help explain how orangutans are likely to be affected as their forest environment is cut down.

“We wanted to measure the energy expenditure as they moved through the trees,” he told BBC Nature, “so we put a mask on [the athletes] to measure their oxygen consumption.”

For one particularly precarious-looking test, the team designed a tall pole that mimicked the flexibility of a tree. The participants then used this to recreate a “tree-sway manoeuvre”.

“This is something the orangutans use to cross gaps,” said Dr Coward. “They sway [the tree] backwards and forwards until they’re able to get across.”

The team found that this method of moving from tree-to-tree used just one tenth of the energy that it cost to climb down and back up.

“As their environment is affected by humans cutting down trees, they are coming across more gaps and those gaps are bigger and more expensive.”

Dr Coward added that, for Sumatran orangutans, climbing down was not an option.

What a great study that not only demonstrates how a sport based on play can help researchers understand other primate behaviors, but it also helps promote conversation for orangutans. 🙂