While at the Indianapolis Zoo, I observed the orangutans and baboons. While observing
the orangutans, I observed one of the females gathering a nest. The female orangutan gathered
laid out straw with her arms and walked bipedally. After compiling the nest into one mound, she
rested on the mound of straw. Contrastingly while observing the baboons, I noticed there was no
nesting material provided in the enclosure. The enclosure was filled with many large rocks with a
rocky cave in the center. Inside the rocky cave, a baboon rested without a nest.
Orangutans live only in rain forests. They spend most of their lives in the trees. They
create nests in trees. They build new nests in new places almost every day. They bring together
different nesting materials such as brush and branches in the tree canopies. Baboons also live in
rain forests, but also live in rocky areas, savannas, and high elevations. While baboons can climb
trees, they spend more time on the ground. However, like orangutans, baboons also prefer to
sleep higher up. Baboons sleep in cliffs and tree canopies, sleeping in new areas every few days.
In the wild, baboons were observed to prefer sleeping sites with a large number of tall,
healthy trees. Groups of baboons with higher statuses occupied preferential sites more often.
However, the baboons were also observed to not remain in a sleeping site for long (Markham
2016). In the Indianapolis Zoo, both orangutans and baboons were observed. The orangutans
were observed to sleep longer. They almost always built platforms to sleep. They slept in more
comfortable resting positions and experienced deeper sleep. The baboons very rarely built nests,
slept in more guarded positions, and huddled together (Samson 2015).
The studies I read supported my observations. Orangutans build nests when sleeping.
This coincides with the nesting behavior I witnessed. They sleep in the treetops but are more
restful and less guarded. This explains the orangutan sleeping alone with no other animals.
Baboons are more guarded. They chose more protected sleeping areas and spent less energy on
comfortability. This was shown in the lack of nesting. Both the orangutans and baboons
exhibited flexibility in sleeping area and commonly changed their place.
Annotated Bibliography
Markham, A. C., Alberts, S. C., & Altmann, J. (2016). Haven for the night: sleeping site selection in a wild
primate. Behavioral Ecology, 27(1), 29-35. Cited by 30.
Samson, D. R., & Shumaker, R. W. (2015). Orangutans (Pongo spp.) have deeper, more efficient sleep
than baboons (Papio papio) in captivity. American Journal of Physical Anthropology, 157(3), 421-427.
Cited by 33.