Giant Orangutans Becoming Smaller Over Time

 Last week, I read a blog post from a peer that talked about birds having smaller bodies over time due to climate change and other outside factors. So, I wondered if there were any other animals that were going through the same thing, and there is. Orangutans. 

 

The discovery of these ancient fossils were mainly found in Southeast Asia, where they thrived and lived in the forests on the islands of Sumatra and Borneo. While observing the fossils and the teeth, they discovered that they all belonged to the same species that had progressively gotten smaller over 2 million years. 

 

Ancient orangutans were actually giants. From around 2 million to 111,000 years ago, orangutans had a body mass of about 96 kilograms (~212 pounds), which is double the size of orangutans that exist today. From around 111,000 years ago, orangutans progressively had gotten smaller but still quite large, with a body mass of about 80 kilograms (~176 pounds). Which is still a lot larger than the orangutans that we see today. 

 

 

Studies have shown that their bodies had begun to get smaller roughly around 400,000 years ago due to the climate becoming cooler. Not only was it just orangutans and other apes bodies that had evolved to be smaller, other animals that resided in Asia had become smaller as well. Such as rhinos and monkeys, and they all had started to shrink around the same time, 400,000 years ago. 

 

Unfortunately, orangutans had died out in Asia, but it isn’t clear when they had. Scientists suspect it is because of climate change and possibly the arrival of humans in their region around more than 60,000 years ago played a factor in their extinction in Asia.

 

Selena Yim (9)

 

https://www.sciencenews.org/article/orangutan-body-size-evolution