Orangutan Obstacles

Can I get extra fries with that Big Mac?

This is Sandra Tsing Loh with the Loh Down on Science. 

Rainforest animals like fruit-loving Bornean orangutans sometimes have trouble finding food due to deforestation and drought! They may eat 70% fewer calories than their bodies require. From a human perspective, that adds up to just ONE Big Mac a day! How do they survive?

Enter Caitlin O’Connell and colleagues from Rutgers University in New Jersey. 

The scientists collected urine from one hundred wild orangutans over eight years. They tested these samples for water and creatinine, a chemical indicator of muscle mass. They then estimated the great apes’ orangutans’ lean body mass – or the mass without fat. 

Results? Using creatinine calculations, the researchers deduced that adult orangutans have adapted by developing lower lean body mass. Baby orangutans, however, managed to maintained stable keep similar lean body masses. The researchers think young apes’ kidneys can’t filter creatinine as well. 

These findings emphasize how impactful human-driven environmental change can be. 

Who could survive on just ONE Big Mac a day? The orangutans sure aren’t LOVIN’ it!


Reference: O’Connell, C. A., DiGiorgio, A. L., Ugarte, A. D., Brittain, R. S., Naumenko, D. J., Utami Atmoko, S. S., & Vogel, E. R. (2021). Wild Bornean orangutans experience muscle catabolism during episodes of fruit scarcity. Scientific Reports, 11(1). https://doi.org/10.1038/s41598-021-89186-4