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Orangutans and humans grow two sets of teeth during their lifetime: a set of 20 baby teeth, and a set of 32 adult teeth that replace the baby set when they fall out. Tooth placement is also the same in both orangutans and humans, with incisors, canines, and molars having similar functions. At birth, orangutan babies depend completely on breast milk, as their teeth do not appear for quite some time, just like human babies. When their first baby teeth appear, baby orangutans begin to eat solid food. 

In November, during a routine check-up on Mema, our medical team found that her lower primary teeth had fallen out. However, the surrogate mothers said they had not noticed any changes in her diet. Mema was still able to bite fruit – and even wood! Not long after this, her adult teeth started to come in.

(Photo Credit: BOSF)

In Forest School, Mema will actively explore right after finishing the fruit and vegetable breakfast provided by the surrogate mothers at the feeding platform. Once she finishes eating, Mema loves to disappear quickly into the thick forest canopy. From time to time, the surrogate mothers have seen Mema playing with Tuti, a young, wild orangutan who often visits the Forest School Group 3 area. When she is satisfied with her adventures, Mema will rest on a thick, comfortable pile of leaves before returning to the complex.

Mema is now seven years old and is in the sub-adult phase of development. Amongst the Group 3 students, Mema and Kristina are the largest and oldest. As is the case with wild orangutans, at this stage Mema is starting to drift away from her surrogate mothers and will only approach them if she feels uncomfortable about something.

At this stage, orangutans tend to start building an interest in the opposite sex, by approaching and observing other individuals. Mema is showing signs of this interest and has confidently started approaching young male orangutans in her group. However, none of the males from Group 3 are going through the same stage as her. 

After assessing Mema’s excellent behaviours and skills, the surrogate mothers and animal welfare team decided to promote Mema and Kristina to Group 4 in February. In Group 4, Mema joined six other orangutans her age and older. We hope that Mema will learn a lot of new skills and pick up more natural behaviours here.

Welcome to Group 4, Mema!

Text by: Communications Team at Nyaru Menteng, Central Kalimantan & BOS Headquarters, Bogor, West Java

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