Fire was integral to human development. Seen in the Greek stories of Prometheus and his gift of fire to civilization to being supported in scientific papers, fire has appeared to be the key to unlocking the secret to human development. More specifically, fire led to cooked food which thus lead to the formation of the human social system.
Now what if humans didn’t exclusively use fire? What if other species could harness this tool? We will explore these questions by analyzing one study of chimpanzees and cooked meals.
What are Chimpanzees?
Chimpanzees or Pan troglodytes are mammals that live off of an omnivorous diet. Because these mammals (including Bonobos) are closely related to humans (sharing 98.7% of our DNA), we share many similarities. One of these similarities is intelligence. For example, in the book “Great Ape Societies“, tool usage, social intelligence and communication through symbols were clear markers of intelligence.
These human-like qualities have left scientists curious to explore the capabilities of these primates.
Chimpanzees and Cooked Food.
In 2015, a paper proved that chimpanzees not only knew how to cook, but preferred it over raw food sources. The paper, written by Felix Warneken and Alexandra G. Rosati, identified this through 9 experiments:
Showed that chimpanzees prefer cooked foods.
Showed that the apes had the patience to wait for cooked food.
Chimpanzees are able to seek-out effective cooking devices and have a preference for them. The experimenters tested through a device, that when given raw food, would give away an equally-sized cooked version.
The chimpanzees had a willingness to cook their own food.
Experiment 5 introduced another 11 apes four years later to repeat experiments 1, 3 and 4. The results of this larger test group confirmed their original findings.
Initially, the prior experiments used white sweet potatoes to test the food preferences of the apes. In experiment 6, the experimenters switched the food source:
- A) Cooked versus raw carrots.
- They found that although chimpanzees preferred the cooked versions of both carrot and potato, cooking had a greater influence on their preference for potatoes.
- B) Other food sources.
- The researchers wanted to find if their cooking skills could be applied to other food sources. As a result of their experiment, they found that their skills could be generalized for other food sources. Furthermore, the apes had cognition of their food preferences: they placed food in the cooking device based on their preference but seldomly “cooked” pre-cooked items.
Attempted to see if the chimpanzees could differentiate between cooking edible items and inedible items. The experiment consequently showed that the chimps cooked edible items at a higher frequency than their non-edible equivalents, further strengthening that apes are aware of the cooking process.
Found that chimpanzees were successful at transporting their food to a cooking device.
This experiment aimed find whether chimps could save their raw food for future cooking. They found that if the chimpanzees anticipated to cook their own food, it would be held on to. However, if there were no clues for future cooking, the raw food was consumed.
Looking at the same study outlined above, studying chimpanzees seems to provide information on not only their psychological capabilities and evolutionary past but also shines a light to support the theory that cooking and fire kick-started our development.
A Red Herring?
Despite the promising findings of this study, other professionals seemed to be skeptical about their findings. For example, one review questions the conclusion in Experiment 2 (showed ability to wait for cooked food), that suggested the apes understood the cooking process. Instead, the critique suggests that it was a matter of “more-preferred cooked potato” versus a “less-preferred raw potato.
Another review on the report, although written by the same people, brings up another valid point by scrutinizing the findings that the apes know how to cook as “these data in total do not more strongly support than conclusion than one grounded in more basic forms of learning . . .”. This critique questioned whether Warneken’s and Rosati’s conclusion was accurate in explaining the primates abilities or whether their findings were inflated.
In the same review, they state that the conclusion made by Warneken and Rosati is insufficient. Because one should not base our studies on a singular species as this does not create “firmer conclusions”.
Although this may not have been the most satisfying article to read (it would have been really cool to discover that another animal can cook) it revealed importance of questioning in science —the heart of the scientific method. Because by continuously questioning our peers, we will only get closer to the correct answer. An answer free from the grip of prejudice and human error.