An Opposable Thumbs Up for Co-Existing

5 min read

I rediscovered David Attenborough’s Life on Earth documentary series two weeks ago, when my four-year-old son had some questions about monkeys after flipping through our National Geographic magazines. 

On You Tube, we watched Attenborough’s now legendary 1978 encounter with a family of mountain gorillas in Rwanda, during which a pair of adorable baby gorillas rolled and sat with him on the lush forest floor. My son was particularly fascinated and asked for several replays while mimicking gorilla rolls and tumbles on the bed.

Yesterday, while browsing at a book shop, I picked up Attenborough’s A Life on Our Planet: My Witness Statement and a Vision for the Future. Flipping through the book, I come across Attenborough’s description of this exact gorilla scene. He had intended to explain the opposable thumb’s evolutionary significance on camera when the baby gorillas drew him into their gentle and playful exchange. 

The development of strong opposable thumbs, which allows for contact between the thumbs and other fingers, facilitated high levels of manual dexterity and has been described as the “killer app” that gave primates and early humans an evolutionary advantage. Specifically, having strong opposable thumbs was necessary for the making of tools. 

According to paleoanthropologist Katerina Harvati, the making and manipulation of increasingly complex tools in turn encouraged the growth of other cognitive skills –creativity, planning, and adaptation—resulting in a “complex feedback loop”. 

Interestingly, despite our shared opposable thumbs, Singapore scientist and primatologist Dr Andie Ang has found that while individual human beings demonstrate a preference for right-handedness or left-handedness, non-human primates do not display similar preferences. 

Slow Loris

The slow-loris is an exception. Individual slow-loris gravitate to either right-handedness or left-handedness but do not display any specific preference as a population. In contrast, humans are 90 percent right-handed. In her fascinating interview, Ang also speaks about the importance of primate conservation and Primate Watch, an initiative that aims to be a “tripadvisor” for watching primates in their natural habitat.

Our favourite place in Singapore to watch monkeys is Windsor Nature Park, less developed than nearby MacRitchie Reservoir but with winding footpaths still accessible by little feet. The first time we visited, our then 2-year-old city-slicker son asked to be carried on his father’s shoulders, Now, he often walks or runs along in front of us, stopping to point and whisper when he sees macaques, squirrels, fish, or forest ants. 

During one walk, we saw a mother macaque accidentally drop a piece of fruit onto the forest undergrowth from her perch in the tree. Full of ignorant good intentions, I picked up the dropped fruit and tried to place it on the footpath for her easy retrieval. What a terrible mistake! 

In a flash, the mother macaque leapt down from the tree to give me a piece of her mind. I tried to hide behind my husband (and my son), but she cleverly circled them to bare her teeth at me before picking up her fruit and leaping back into the trees. We have been back many times since and she seems to have forgiven me. I have also read up on how to keep a respectful distance


Reading Attenborough’s words about his magical meeting with the gorillas, I was reminded of my own brief macaque encounter. Of my ignorance, mistake, and momentary fear. 

 “Their sight, their hearing, their sense of smell are so similar to ours that they see the world the same way as we do. We live in the same sort of social groups with largely permanent family relationships. They walk around on the ground as we do, though they are immensely more powerful than we are. So if there were ever a possibility of escaping the human condition and living imaginatively in another creature’s world, it must be with the gorilla. The male is an enormously powerful creature but he only uses his strength when he is protecting his family and it is very rare that there is violence within the group. So it seems really very unfair that Man should have chosen the gorilla to symbolize everything that is aggressive and violent, when that is the one thing the gorilla is not – and that we are.” (pages 59-60)

Our common fear of wild animals, even as we continue to learn much from them, reminds me of one of my son’s favorite books – Macaques in our Estate by Emily Lim. The book tells the story of human-macaque interactions in Singapore and the importance of co-existence through the eyes and adventures of two children. 

While Singapore has domestic laws protecting wildlife and is party to CITIES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora), it is harder to change popular mindsets and culture. So often, our response to the natural behavior of monkeys and other wildlife is annoyance or even violence. 

The learning of our similarities and differences, as well as the larger story of evolution, may go some way to cultivating a culture of respect and co-existence. It would be a great loss if the day comes when we are only able to point out monkeys to our children on the screen or in the zoo, while telling them the story of our opposable thumbs. 

Written by Cheah Wui Ling
Illustrated by Lim Daphne


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