Saturday, November 19, 2011

Culture in Human's Closest Relatives

We've always known apes, chimpanzees, and orangutans were closely related to humans biologically, but a recent study shows that this relationship goes a little bit deeper. Researchers from the University of Zurich have compiled data on orangutans located in Borneo and Sumatra to help answer the question of whether various environmental influences or genetic factors dictate how orangutans behave in nature. What they found surprised them.

Culture is easily seen and understood among human populations. For example, we immediately experience changes in culture as we go on vacation not only to domestic areas like Florida or California, but even more so in international countries like Spain and Japan. Countless times humans have undergone that awkward meeting with an international citizen and learned that kissing their cheek is equivalent to shaking their hand. Various types of culture change in humans is due partly to environmental factors and genetics, but the main differences are socially learned from parent to offspring. In the study, the researchers found a striking similarity among orangutans and humans. Of the two regions the researchers studied, Borneo and Sumatra, the orangutan populations are isolated and have no way of naturally interacting with the other population. This means that there is no way for the two populations of subjects to ever come into contact with the another. The environmental influences as well as genetic factors are similar between the two populations, but still behave differently. The researcher's study is helping bridge the behavioral gap between primates and humans. With evidence like this, it is wondered what other species might be making the same adaptation.

The study was especially successful because of several variables. Michael Krutzen, one of the researchers of the study, helped record over 100,000 hours of behavioral data. The extreme amount of evidence was important to the study in order to notice trends of behavior between infants, adolescents, and adult orangutans. Monitoring the behavior and growth of the two populations helped the researchers see consistency within a specific island culture for orangutans. Other important variables in the study was the use of satellite imaging and remote sensing technologies. The use of these techniques further monitored the primates in their own natural habitat keeping both the researchers and orangutans out of harm's way while also gathering meaningful data.

Some of the differences noticed between the two populations are bedtime rituals, eating habits, and sexual practices. The way orangutans in one population hunt for their food is an interesting aspect the researchers noticed. Certain tools and means of obtaining their diet are different in the populations. For example, the orangutans on one island had the ability to extract seeds from a local fruit (Neesia Fruit) as a main source of food. However, in regards to the other population where the food source was equally available, the orangutans neglected the seeds. Another difference between the two populations was how the groups interacted before they slept. For the orangutans at one site, they let out a loud cheer just before they were going to rest. This ritual, among others, were not seen at other sites and helps prove the theory of primates socially passing down their behavior to their offspring.

This may only be minor differences between the two populations of orangutans, but it illustrates a snapshot into how a species adapts to its environment, which is a vital role in the survivability of a species. Over time, if the population that eats the seeds from high atop the forest, they may adapt further and develop certain attributes to help them master their seed diet. That could be changes in the shape of teeth to better break up seeds or hands that make it easier to climb higher and retrieve the seeds.

"Now we know that the roots of human culture go much deeper than previously thought. Human culture is built on a solid foundation that is many millions of years old and is shared with the other great apes," says researcher Michael Krutzen. The similarities we humans share with our closest relatives goes beyond anatomical and genetic bonds and into cultural and behavioral realms as well. 

Helpful Link:
Bronx Cheer-Imitates the loud cheer some populations of orangutans do before bedtime.


  1. This post was interesting in seeing Darwin's theory of natural selection in today's world. It is also makes it a lot easier to understand why we act so much different from other cultures.

  2. Thanks Brad. When I first read the articles I thought it was interesting to see the difference in culture just like we humans experience culture change and culture shock. I would assume the orangutans would feel just as awkward as we do when introduced to someone from another culture.