By Christophe Boesch
Philosophers, anthropologists, psychologists and others have been addressing the question of “What makes us humans?” for centuries. However, we have always been limited in our ability to answer that question by the fact that in most comparative studies either humans and/or chimpanzees, our closest living relatives, have been placed in speciesunnatural conditions or have been tested in species untypical situations. Thereby, either species were facing a systematic disadvantage that has hampered our ability to understand “What makes us humans?”
In theory, the solution to this quandary is rather straightforward, as it would “only” require to select some natural tasks that are performed by both species and to compare them in situ. My goal in this project is to do exactly this and compare humans with chimpanzees solving two similar natural tasks: Finding food producing trees in their natural environment and cracking wild nuts.
By making the human / chimpanzee comparison with natural populations solving similar natural daily tasks with all their local and historical accumulated knowledge of the technical challenge, we hope to be able to detect more precisely species differences that are only affected by the specie-specific way to solve such ecological challenges.
Finding food producing trees
Finding food sources is a basic challenge that all animals, including humans, have to solve. Finding sources such as trees may be complicated by the visibility conditions prevailing in different environments. Therefore, we are comparing the food tree finding strategies of the Mbendjele foragers in the Republic of Congo, living in a closed tropical rainforest, similar to those of the Taï chimpanzees in Côte d’Ivoire, both populations facing similar challenges to find their food.
As in previous studies (Normand et al. 2009a, b, Janmaat et al. 2013, 2014, 2016, Ban et al. 2016), we adopted exactly the same methodology for a similar natural task which should allow us to improve our knowledge of the similarities and differences between humans and chimpanzees, as well as understand the impact of ecological differences. Karline Janmaat and Haneul Jang have spent three seasons in the forest with the Mbendjele women following individual women in the same way than we did previously with Taï chimpanzee females to collect the best possible comparative data.