What crows teach us about death | Kaeli Swift (re-release)

Elise Hu introduces an October TED Talks Daily playlist built around five “haunting” talks, including subjects such as grieving crows and zombie roaches. She frames the series as spooky but fundamentally curious: unusual animal behavior can reveal how fascinating the natural world is. The featured talk is Kaeli Swift's 2020 presentation about what crows do when they encounter one of their dead, including experiments involving masks and staged “crow funerals.” The episode then runs three sponsor messages before the talk. Walmart Business presents procurement and logistics as distractions from big-picture work and promotes its assortment, prices, shipping, and free business account. TikTok uses an interior designer's discussion of ceiling height and room size to suggest that physical environments shape thought. Apple Card promotes 2% Daily Cash through Apple Pay for seasonal purchases, with the card available through the iPhone Wallet app. Hu then introduces the central question: whether crows' responses to their dead are simply danger-management behavior or something more complex that might illuminate the origins of human death rituals.

Swift begins by noting that humans have intentionally buried their dead for roughly 100,000 years, though no one can know whether early burials were meant to honor the deceased, prevent scavenging, limit disease, or simply remove the body from view. She argues that humans are not alone in attending to the dead. Corvids—crows, ravens, magpies, and jays—also do so, and she mentions the old story in which God sends a raven to teach Cain how to bury Abel. Swift describes comparative thanatology, a formal field name introduced only in 2016. One category contains predictable, experimentally studied hygiene behaviors among social insects: bees, ants, and termites remove or consume corpses or construct tombs. Rats reliably bury cage mates that have been dead for 48 hours. The second category includes more variable behaviors known largely through observation. Elephants attend to their dead and their bones; primates groom, guard, and transport corpses, especially dead infants; and dolphins have been seen doing similar things. Swift cites Tahlequah, an orca from the resident J-Pod in Puget Sound, which carried her dead calf for 17 days in summer 2018. That event was emotionally striking but did not establish whether the cause was grief, confusion, or a behavior more common among orcas than scientists realize.

Crows usually respond to a dead crow when the discovering bird sounds an alarm and recruits others into a mob. Swift had also heard reports of silent vigils and of crows placing objects, including sticks and candy wrappers, near bodies. Because crows have large brains relative to their bodies and complex social lives, she wanted to determine whether their gatherings reflected social investigation, grief, or learning about danger. As a graduate student, she focused on two testable questions: could crows learn to recognize a person associated with a dead crow, and could they learn that a location where a crow had died was dangerous? For the experiment, Swift fed a breeding pair in a Seattle neighborhood for three days to establish how quickly they came to a food pile. On the fourth day, one of seven masked participants—“Linda”—stood for 30 minutes holding a plate containing a dead crow while Swift recorded the birds' behavior. A week later, the masked person returned without the corpse. Over the following six weeks, most crows treated masks associated with dead crows as threats, showing behaviors such as alarm calling and dive-bombing. The crows also became significantly less willing to approach the food pile after the funeral events, unlike the control groups. Swift concluded that crows associate both particular human faces and particular places with the danger represented by a dead crow.

Swift cautions that the danger-learning explanation is useful but incomplete. In a follow-up experiment, she presented dead crows without an accompanying predator and observed a startling combination of alarm, aggression, and sexual arousal. One crow forcefully pecked the body, another bystander joined in, and sexual behavior also occurred. Rather than treating this dramatic episode as proof of a special crow ritual, Swift asks whether it is representative of what normally happens. After hundreds of trials involving dead crows placed on the territories of hundreds of pairs, the researchers found that contact with the corpse—sexual, aggressive, or exploratory—occurred only 30 percent of the time. It was therefore a minority pattern, not a general rule. Swift says that behaviors such as biting, beating, and sex around the dead are not confined to crows: scientists have documented them in primates and dolphins as well. The broader lesson is that popular accounts tend to emphasize affectionate behaviors such as grooming and guarding, while the full range of animal responses is messier. Crows may have an adaptive reason to investigate their dead, especially learning about danger, but no single narrative explains every response.

Swift ends by placing crows between the two broad animal patterns she described. Like social insects, they may have a strong adaptive reason to attend to corpses—in their case, learning where danger is and which predators to avoid. That mechanism could even have contributed to the development of human rituals surrounding the dead. But the experiments also show why scientists should not turn unusual observations into universal explanations: crows sometimes alarm, sometimes attack, sometimes investigate, and only occasionally display sexual behavior. Her conclusion is that the natural world does not offer one tidy account of death rituals. The same complexity appears in elephants, primates, dolphins, and humans, and the available evidence does not yet let researchers reconstruct a complete “time machine” to the practices and motivations of early humans. Swift calls the continuing investigation a fascinating ride. After the talk, TED credits its production team and directs listeners to podcasts.ted.com. Additional post-talk advertising promotes Capital One's Spark Cash Plus card and ServiceNow's AI specialists, while the episode ends with Elise Hu thanking listeners.