Chimpanzees in Kibale National Park

In 2018, researchers in Uganda witnessed a female chimpanzee carrying her newborn infant, which had albinism, a rare condition in this species. Chimpanzee mothers often separate from the group to give birth, protecting their babies from infanticide. The researchers observed the mother rejoining the group, allowing them to document the reactions of her mates to the infant’s unusual appearance.

The chimpanzees displayed fear instead of the usual curiosity and care shown towards newborns. Their fur stood on end, and they made calls associated with dangerous animals like snakes or humans. Violence ensued, and the alpha male, with his allies, killed and dismembered the infant. After the death, the chimpanzees’ behavior shifted dramatically, and they became fascinated by the corpse. They sniffed, poked, and tugged at its fur, comparing it to their own, captivated by this being that smelled like a chimp but looked so different.

This tragic event provides compelling evidence that chimpanzees understand death. Their change in attitude after the baby’s death is key. What was initially perceived as a threat transformed into an intriguing object worthy of thorough investigation, so harmless as to allow physical exploration. It suggests the chimps recognized that the unusual animal could no longer pose a threat.

However, some scientists studying animals’ relationship with death might disagree with this conclusion. They may argue that understanding death implies comprehending its finality, inevitability, unpredictability, and impact on all beings, including oneself. This perspective is rooted in what I call “intellectual anthropocentrism,” the assumption that the only way to understand death is the human way. This belief suggests animals either possess a human-like concept of death or none at all.

This notion is inaccurate. Intellectual anthropocentrism biases comparative thanatology, the study of how animals deal with and understand death. To eliminate this bias, we must acknowledge that the concept of death exists on a spectrum, not as an all-or-nothing phenomenon. When studying animal understanding of death, we should not start with the complex human concept, but rather with what I call the “minimal understanding of death.” This entails grasping that dead individuals do not behave as living beings of their kind typically do and that this state is irreversible. The chimpanzees’ behavior strongly suggests they understood this minimal concept of death.

Another bias affecting comparative thanatology is what I call “emotional anthropocentrism.” This bias dictates that animal reactions to death are only noteworthy when they appear human-like. This bias has led comparative thanatologists to focus on mourning behavior in animals, exemplified by the story of “Tahlequah,” the orca who carried her dead baby for 17 days and over 1000 miles, or “Koko,” the gorilla who attempted to suckle from her dead mother’s breast despite being weaned. Don’t misunderstand: mourning is a real and significant phenomenon deserving our attention. However, focusing solely on mourning behavior may obscure the bigger picture.

Consider the chimpanzees again. Their behavior was not characterized by mourning but rather by curiosity. This does not diminish their understanding of what had happened. Grief does not signal a superior or deeper understanding of death. It reflects the existence of a strong social bond between the mourner and the deceased.

There are many emotional reactions to death beyond grieving. One might react with joy upon inheriting a large sum of money, with anger if the deceased owed money, with excitement or hunger in a survival situation, or with indifference if the deceased was unknown or insignificant. While these reactions are taboo in our societies and not publicly acknowledged, they are still possible. Importantly, they do not negate an understanding of what happened. The polar bear catching a seal might comprehend death as well as the grieving monkey mother clinging to her baby’s corpse, even though the former perceives it as a gain, not a loss.

The biases of emotional and intellectual anthropocentrism have obscured the diverse ways animals react to death beyond what our societies deem acceptable. The concept of death, far from being a complex intellectual achievement exclusive to highly intelligent species, is easily acquired and linked to survival skills. By eliminating these biases, we will recognize that understanding death is widespread throughout the animal kingdom, more diverse and common than previously believed.