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Unwavering fate -

There is nothing more human than being anguished by death. It's a topic that intrigues, scares, and keeps us evolving. Everything humans have invented stems from the desire to survive or delay our inevitable fate.

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Instinct -

The same survival behavior is evident in the animal kingdom. But what do animals know about death, beyond a biological survival instinct?

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The only ones? -

Scientists and philosophers have had mixed views on whether we share this trait with nonhuman animals, since having a concept of death is tied up with larger questions around animal consciousness.

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Resistance -

For much of the 20th century, many scientists didn't believe animals understood the difference between life and death. "Monkeys and apes do not recognize death, as they react to their companions as if the latter were alive but passive," wrote primatologist Solly Zuckerman in 1932.

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First studies -

Comparative thanatology is the study of how animals, both human and nonhuman, experience and understand death. It is still considered a relatively new field within the scientific community, with the first main studies published about a decade ago.

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Pioneer -

Trailblazing researcher and primatologist Jane Goodall spent years studying a chimpanzee tribe in Tanzania during the 1960s. She was the first to identify human-like behaviors among the primates, including their apparent grieving.

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Grief among primates -

Goodall documented a case where a baby chimpanzee experienced such intense grief after losing its mother that it eventually passed away. Other cases included a chimpanzee mother carrying her dead offspring until it became mummified, and a chimp daughter standing still alongside her mother's dead body for an extended period, as if mourning her remains.

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Emotional animals -

Animal rituals and reactions to philosophical topics like death, love, and social dynamics have intrigued researchers for years. In the book 'When Elephants Weep' (1996), authors Jeffrey Masson and Susan McCarthy present fascinating anecdotes that offer compelling evidence of animal emotions, from dancing squirrels to spiteful killer whales.

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Touching rituals -

Caitlin O'Connell studied elephants for 30 years and published a book detailing their rituals, including grieving for lost loved ones.

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But do they really understand death? -

Contributing to advancements in the field, Spanish animal mind philosopher and academic Susana Monsó recently published one of the first books comparing understandings of death between species. She deep dives into stories of ants attending their own funerals, chimpanzees cleaning the teeth of their dead, and whales carrying their dead for weeks.

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Comprehension or strategy? -

Monsó touches on how studies show that animals respond to death in a variety of ways. On one end of the spectrum, some animals exhibit automatic, hardwired behaviors, like the "playing dead" defense mechanism.

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Functional response -

The author uses the opossum's example to examine animals' intricate interpretation of death. When threatened, it becomes paralyzed. Its body temperature plummets, its breathing and heart rates drop to a minimum, and its glands simulate the smell of a decaying corpse.

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Not just instinct -

On the other hand, animals also seem to have a deeper perception of death, and it can cause more nuanced reactions. Monsó and other researchers have ample evidence that animals have such individualized responses.

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Saying goodbye -

In her book, O'Connell describes a group of young elephants that return to the site where a fellow band member died. For several months, they keep returning, using their trunks to gently touch the deceased animal, in a behavior reminiscent of a wake.

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Grieving -

When the body starts to decompose, the elephants gather the sand surrounding it and place it on their chests, seemingly attempting to carry their friend with them. This behavior is similar to how some people handle the ashes of a cremated loved one.

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Still not conclusive -

Monsó points out that grief is a useful indicator of strong emotional bonds, including love, but not necessarily a concept of death. These two approaches, grief and death, can overlap, but they don't always occur together.

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What does it mean to understand death? -

Researchers seem to agree there are four components of human adults’ understanding of death: inevitability, irreversibility, non-functionality, and causality.

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It takes time -

Even humans take time to grasp such complex concepts. Children don't develop a concept of death overnight; it takes them several years—up to 10, according to developmental psychologists.

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It takes time -

Children learn between the ages of four and seven that death is not temporary or reversible. According to a 2004 paper in the journal Cognition, children understand death as "a permanent loss of agency."

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Back to basics -

As adults, we start to internalize more abstract and culturally tied notions of death. To avoid socialized adult interpretations, Monsó applied a list of seven criteria used by child developmental psychologists to assess animals' understanding of death.

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Their understanding -

Her research suggests that large-brained animals, through repeated exposure to death, likely understand these two components: non-functionality (recognizing that the dead no longer exhibit mental and bodily functions) and irreversibility (understanding that the dead cannot come back to life).

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The "last rally" -

Like humans, animals also seem to experience "terminal lucidity," a burst of energy and clarity shortly before death. This could have an evolutionary benefit, said biologist Rupert Sheldrake. "In the wild, an animal that instinctively knows it is dying can detach itself from the pack and go somewhere its corpse won't spread disease."

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Language barrier -

Proving they have this basic understanding is difficult. But while researchers cannot interview animals, they can monitor their hormonal shifts. For example, baboon cortisol levels spike when they lose someone close.

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Getting close? -

There have been a few attempts to communicate linguistically about death with great apes trained to use American Sign Language.

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Maternal bond -

In a renowned academic study, the chimpanzee Washoe's baby was removed from her care after a fatal illness. When researcher Roger Fouts returned, Washoe looked at him and signed, "Baby?"

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Maternal bond -

Fouts replied: "Baby dead, baby gone, baby finished." According to Fouts, "Washoe dropped her cradled arms to her lap. She moved over to a far corner and looked away, her eyes vacant."

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Open questions -

Comparative thanatologists don't have all the answers yet. They still want to understand if animals can comprehend that all creatures die, including themselves, and understand the biological causes of death.

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Shift in perspective -

With the results so far, researchers are also raising questions about what this means for us as a species, morally.

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Consoling effect -

Monsó wants her research to carry a hopeful note, suggesting that if we accept our animal nature, we might better face our mortality. "I think it has to do with normalizing it, understanding that it's a fact of life, and not something unfair that happens to us. (...) Pretending it won't happen makes the fear of death stronger than if you face it head-on and accept it for what it is," she says.

Sources: (The Guardian) (El País) (Cell Press) (The Week) (Vice) (The Inquisitive Biologist) 

See also: Strange things grief does to your body

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