To put some numbers on the human/orangutan comparison: a recent large study of normal weight adult human women living in Texas (Butte et al 2003 American Journal of Clinical Nutrition) found that on average, women weighing 125 lbs burn about 2400 kilocalories per day. By comparison, the adult female orangutans in our study, which also weigh 125 lbs, burn about 1600 kilocalories per day. So the difference is actually pretty large.
There are a lot of studies out there like the one you suggest -- measuring energy use in sedentary humans (go to PubMed, the NIH database for research articles, and search "human doubly labeled water" and you get about 550 hits). One thing that is striking if you look at those articles: the "2000 calories a day" benchmark that people often use/cite as normal for adults is bogus -- people generally use more. So the energy used by orangutans is remarkably low compared to us.
Support Local Journalism.
Join the Riverfront Times Press Club
Local journalism is information. Information is power. And we believe everyone deserves access to accurate independent coverage of their community and state. Our readers helped us continue this coverage in 2020, and we are so grateful for the support.
Help us keep this coverage going in 2021. Whether it's a one-time acknowledgement of this article or an ongoing membership pledge, your support goes to local-based reporting from our small but mighty team.
Join the Riverfront Times Club for as little as $5 a month.