Chapter 4
When Sex Becomes Fatal: Reproductive Cannibalism
While the praying mantis's reputation for sexual cannibalism is legendary, reality is more nuanced than myth. Among the 2,200 mantis species, females don't necessarily decapitate their mates as a matter of course. Laboratory conditions-where males can't escape-often exaggerate this behavior, though it does occur in nature.
The redback spider demonstrates perhaps the most extreme example of sexual cannibalism. The tiny male (one-fifth the female's size) initiates courtship by bouncing and waving on her web. After complex foreplay, he performs a 180-degree somersault during copulation, positioning his abdomen against the female's mouthparts. She immediately begins consuming him while they mate. After the first copulation, the half-eaten male returns for a second round before being completely consumed. This seemingly suicidal behavior benefits the male by ensuring females become less receptive to other suitors, allowing longer copulation and increasing his chances of fathering more offspring.
Sexual cannibalism typically follows the "small-get-cannibalized" rule, with females usually eating males due to sexual dimorphism. However, exceptions exist in species like sand-dwelling wolf spiders and water spiders where males are larger and sometimes cannibalize females based on their fitness and mating history.
Even hermaphroditic land snails exhibit bizarre mating behaviors, including firing calcified "love darts" at potential mates. These barbed projectiles contain chemicals that prevent digestive enzymes from destroying sperm, doubling fertilization success. Ronald Chase believes the Cupid myth likely originated from Ancient Greeks observing this peculiar snail behavior-a far cry from our romantic modern interpretation.
Chapter 5
When Crowds Turn Deadly: Density-Dependent Cannibalism
Overcrowded conditions often trigger cannibalism, especially when combined with hunger and decreased alternative food sources-a pattern that applies across species from insects to humans. Mormon crickets (actually jumbo katydids) exemplify this phenomenon perfectly. These flightless insects form massive swarms under favorable spring conditions, with millions hatching simultaneously and beginning coordinated marches across the landscape.
According to expert Stephen Simpson, these swarms serve a protective function-individuals separated from the group suffer 50-60 percent mortality from predators, while those within remain relatively safe. However, this protection comes with a cost. As the swarm moves, individuals face a terrible choice: keep moving or be eaten by those behind you. Mormon crickets need protein and salt to develop their reproductive organs, and when vegetation can't provide these nutrients, they turn to the next available source-each other.
The crickets' march becomes a macabre forced migration where the alternative to forward movement is becoming food for your fellows. This pattern appears in other species too, including commercial poultry operations where crowded conditions lead to cannibalistic pecking. These behaviors aren't signs of inherent viciousness but rather adaptive responses to environmental pressures-a pattern that emerges repeatedly across the animal kingdom and, disturbingly, in human history as well.
Chapter 6
Climate Change and Carnivores: The Polar Bear Question
Polar bears have become the subject of numerous headlines linking cannibalism to climate change and disappearing Arctic ice. As a vertebrate zoologist, I wanted to investigate whether their diet had truly changed and if humans played a role. Polar bears (Ursus maritimus) rank among the world's largest carnivores and, unlike most bears that evolved omnivorous habits, they've re-evolved carnassial teeth-specialized shearing molars reflecting their strictly meat-eating diet of primarily ringed and bearded seals.
Cannibalism has been documented in at least 14 carnivore species, typically occurring due to food scarcity, rival elimination, or increased mating opportunities. In lions, heterocannibalism (males eating cubs sired by other males) serves as a reproductive strategy-by killing cubs, incoming males terminate maternal investment in unrelated offspring, causing females to become sexually receptive almost immediately rather than remaining unreceptive for a year and a half after giving birth.
Wildlife biologist Mitchell Taylor confirms that polar bears readily eat other polar bears when they can do so without excessive risk. Males of most North American bear species kill and eat cubs whenever possible, providing both nutritional and reproductive benefits as females come into estrus more quickly after losing offspring. This explains why mother bears are extremely protective and choose den sites far from males.
In 2006, researcher Stephen Amstrup documented three unusual cannibalism incidents in the southern Beaufort Sea, hypothesizing they might be linked to nutritional stress from longer ice-free seasons. Unfortunately, media reports sensationalized these findings by neglecting to mention that polar bear cannibalism has been documented since at least 1897. This gave climate change deniers ammunition to discredit valid scientific concerns about how reduced sea ice might be increasing cannibalistic behavior-a reminder that science must be communicated carefully when addressing politically charged topics.
Chapter 7
The Neanderthal Question: Our Cannibalistic Cousins?
The discovery of Neanderthal remains in 1856 near Dusseldorf, Germany initially generated little excitement in a pre-Darwinian scientific community. Marcellin Pierre Boule's influential but deeply flawed reconstruction depicted Neanderthals as stooped, ape-like creatures with limited intelligence. This portrayal cemented the public image of Neanderthals as brutish and primitive, with "Neanderthal" becoming synonymous with savagery and stupidity. H.G. Wells reinforced this stereotype in his 1921 story "The Grisly Folk," depicting them as cannibalistic ogres who ate children and were rightfully exterminated by modern humans.
Since then, Neanderthals have undergone significant rehabilitation in scientific understanding. Modern research shows they were highly intelligent with brain capacities sometimes exceeding modern humans. They used fire, wore clothing, and created sophisticated stone tools. Evidence for Neanderthal cannibalism comes from sites in Spain, France, and Croatia, where bones show "patterns of processing" similar to those found on animal remains-cut marks, gnawing, percussion hammering, and fracturing to access marrow. At Moula-Guercy in France, six Neanderthal remains were found alongside deer bones, all processed similarly, with skulls smashed, jaw muscles filleted, and tongues removed.
Their ancestors, Homo antecessor, also practiced cannibalism at Atapuerca in Spain. These 530,000-year-old remains showed identical damage patterns to animal bones processed for food. Unlike survival cannibalism, the abundance of game animals suggests these hominids may have simply considered conspecifics as acceptable food sources. This raises profound questions about how deeply cannibalism taboos are wired into human psychology, and whether our revulsion represents an evolutionary adaptation or merely a cultural construct.
Chapter 8
Colonial Cannibalism Narratives: Justifying Conquest
When Christopher Columbus arrived in the Caribbean in 1492, he encountered the peaceful Taino people who warned him about the fierce Caribs-allegedly cannibals who raided neighboring islands for human flesh. Columbus seized upon these stories, using them to justify enslaving the indigenous peoples he encountered. The association between "Carib" and "cannibal" became so entrenched that the very word "cannibal" derives from a Spanish corruption of "Carib."
This narrative of indigenous cannibalism conveniently served European colonial interests, providing moral justification for conquest, enslavement, and genocide. The Spanish monarchy initially forbade enslaving indigenous peoples unless they were cannibals, creating a powerful incentive for colonizers to label all natives as man-eaters. This pattern repeated throughout colonial history-Europeans would arrive in new territories, hear stories about neighboring tribes practicing cannibalism, and use these allegations to justify brutal subjugation.
Historical evidence suggests that while ritual cannibalism may have occurred in some Caribbean societies, European accounts were wildly exaggerated and often fabricated. Many supposed "eyewitness" reports were actually based on hearsay or deliberate propaganda. Peter Martyr, an Italian cleric who never visited the New World, embellished Dr. Chanca's account of the "cannibal hut" in his influential book De Orbe Novo, transforming a single dwelling into multiple houses with gruesome scenes of human flesh being prepared alongside animal meat.
The question remains: did Caribbean cannibalism actually exist when Columbus arrived? Anthropologist Neil Whitehead suggests that while many reports were "imperial propaganda," the Caribs likely practiced forms of ritualized cannibalism. Historical accounts place Amerindian cannibalism in social contexts-as funerary rites or war rituals rather than dietary practices. The evidence remains contentious, with some scholars like William Arens challenging the entire narrative, arguing that ritual cannibalism was largely fabricated to justify colonial subjugation-a controversial stance that sparked fierce academic debate but raised important questions about how "Others" have been dehumanized throughout history.
Chapter 9
The Worst Party Ever: Survival Cannibalism in the Sierra Nevada
In June, I joined Kristin Johnson, John Grebenkemper and his border collie Kayle (trained in Historical Human Remains Detection) at Alder Creek in the Sierra Nevada foothills. In the 105F heat, we searched the meadow where members of the infamous Donner Party had once been stranded. Though I initially thought the Donner Party story was too well-known to warrant further investigation, I discovered that significant research was still uncovering new aspects of this American tragedy.
In summer 1846, 87 pioneers left Independence, Missouri for California, taking the ill-advised Hastings Cutoff that proved 125 miles longer than the established route. This detour forced them to blaze trails through the Wasatch Range and trek across Utah's Great Salt Desert, causing delays, equipment failures, and deaths. By September, they rejoined the traditional trail, but the month-long delay proved catastrophic. The group fractured along class and family lines as they struggled along the depleted Humboldt River, facing Indian raids and abandoning weaker members.
By late October, the remaining travelers reached the final mountain pass, just 50 miles from safety. But on November 1, they awoke to five-foot snowdrifts blocking their path. The 59 members in the lead group retreated to Truckee Lake (now Donner Lake). The remaining 21 members, including George Donner (the elected leader), his brother Jacob, and their families, were stranded at Alder Creek, eight miles away.
On December 16, seventeen desperate people from Truckee Lake fashioned snowshoes and attempted escape. Two turned back, leaving fifteen (later called "The Forlorn Hope") to battle through the country's snowiest region. By January 17, 1847, only seven survivors reached Johnson Ranch in the Sacramento Valley after 33 days with just a week's worth of rations. The others had perished and been cannibalized.
Anthropologist Donald Grayson's demographic analysis revealed striking survival patterns among the Donner Party. Children under 5 and adults over 49 experienced high mortality (62.5% and 100% respectively). Remarkably, 53.1% of males died while only 29.4% of females perished, with men dying sooner. Most striking was that all 11 bachelors over 18 died, while only half of the married men traveling with families perished. This gender disparity stems from both biology and behavior. Women metabolize protein more slowly, require fewer calories, possess greater fat reserves for insulation, and performed less physically demanding tasks. The married men's survival advantage likely relates to stress hormone differences-studies show bachelors have higher cortisol levels during stress, while marriage provides a buffer against stress responses.
Like animal cannibalism that occurs for evolutionary reasons-reducing competition, sexual behavior, or parental care-human cannibalism under extreme conditions represents a predictable biological response to specific stresses. Just as male spiders sacrifice themselves to mates to increase offspring survival, bodies of Donner Party members served a similar function for their families.
Chapter 10
When Eating People Is Medicine: European Cannibalism
While Europeans were condemning indigenous peoples as "savages" for alleged cannibalism, medicinal cannibalism remained widespread throughout Renaissance Europe. Blood was the most commonly consumed human tissue, prescribed by physicians for treating epilepsy. Following Galen's theory of bodily humors, epileptics often collected fresh blood at public executions. Blood was consumed fresh, dried into powder, or mixed into elixirs, and remained prescribed by English physicians until the mid-18th century.
The rise of Paracelsian medicine in the 16th century further popularized medicinal cannibalism. Paracelsus (1493-1541), considered the Father of Chemical Pharmacology, inspired physicians to prescribe medications made from human body parts, including powdered skull for epilepsy and dysentery. Richard Sugg documents that "human liver, oil distilled from brains, pulverized heart, bladder stones, warm blood, breast milk, and extract of gall" were all used medicinally, along with bones, flesh, and fat.
This practice wasn't limited to commoners-European royalty and intellectuals embraced medicinal cannibalism. King Charles II made his own corpse medicine, while Charles I was made into corpse medicine. Other notable advocates included Francis I of France, John Donne, Francis Bacon, and Robert Boyle.
Public executions became increasingly gruesome as demand for human body parts grew, with prisoners often harvested while still alive. Human skulls were used to grow "skull moss"-lichens and mosses cultivated on crania for medicinal use. The most famous example was "mumia"-powdered mummy consumed for ailments from epilepsy to upset stomachs. When Egyptian mummy supplies ran short, "artificial mummies" were created from fresh corpses using specific preparation methods.
The practice finally declined during the Enlightenment due to changing scientific attitudes, the professionalization of medicine, new concepts of hygiene, and a more mechanistic view of the human body. Yet modern examples persist, from Keith Richards snorting his father's ashes to the 21st century revival of placentophagy in America-where middle-class women consume their own placentas raw, in smoothies, as jerky, or encapsulated as supplements.
Chapter 11
When Cannibalism Kills: The Kuru Epidemic
In the early 1950s, researchers ventured into New Guinea's Eastern Highlands to study the Fore people, an isolated tribe dying from a mysterious affliction characterized by uncontrollable laughter, tremors, and coordination problems that progressed to inability to swallow and complete loss of bodily control. The disease, called kuru, killed approximately 1% of the population annually.
Daniel Carleton Gajdusek, a Harvard Medical School graduate, arrived in 1957 and began studying kuru, collecting samples while interviewing victims and families. Analysis revealed no evidence of viral infection or toxins, but rather cerebellum regions riddled with holes. NIH researcher Igor Klatzo recognized similarities to Creutzfeldt-Jakob Disease, while another scientist noted parallels to scrapie, a transmissible spongiform encephalopathy affecting sheep.
Cultural anthropologists Robert and Shirley Glasse (now Lindenbaum) arrived in 1961, ultimately connecting kuru to cannibalism. Their research revealed women and children of both sexes participated in ritual consumption of deceased relatives, while adult men generally abstained-perfectly matching kuru's demographic pattern.
The Fore practiced "transumption"-ritual consumption of dead relatives-believing it better to be consumed by loved ones than by maggots. During these ceremonies, women used bamboo knives to cut the corpse into pieces on beds of edible leaves. The flesh was cooked in bamboo containers with ferns, while internal organs were given to specific relatives. The brain, considered a delicacy, was removed after cooking the cracked skull, then mixed with ferns and consumed.
Research traced kuru's origin to around 1900 in Uwami village, spreading to North Fore by 1920 and South Fore by 1930. After cannibalism was prohibited, deaths declined dramatically through the 1960s and 70s. This tragic epidemic would later provide crucial insights when a similar disease emerged in British cattle decades later.
In the 1980s, UK researchers investigated how a strange spongiform encephalopathy was transmitted among dairy cows. The culprit was "meat and bone meal"-a protein supplement made from rendered livestock waste including sick animals. Though used since the 1940s, changes in the rendering process during the early 1980s created perfect conditions for Bovine Spongiform Encephalopathy (BSE) to emerge.
By the 1970s, research had shifted to understanding the infectious agent itself. The scrapie agent proved remarkably resilient-unaffected by disinfectants, heating, freezing, drying, electron beams, or ultraviolet light. Biochemist Stanley Prusiner pursued a revolutionary theory: the agent might be a self-replicating protein. In 1982, he published findings coining the term "prion" to describe an aberrant protein responsible for Transmissible Spongiform Encephalopathies (TSEs). Despite initial controversy, Prusiner won the 1997 Nobel Prize for Medicine for his prion research.
By 1996, scientists confirmed fears of a new disease transmitted to humans through contaminated beef: Variant Creutzfeldt-Jakob disease (vCJD). By 2013, the UK recorded 177 definite and probable vCJD deaths. A 2013 study found one carrier for every 2,000 people in the UK, suggesting the epidemic might continue for decades given kuru's demonstrated 50-year incubation period.
Chapter 12
The Future of Cannibalism: Ecological Collapse
Cannibalism makes evolutionary sense in nature-from spiders consuming males to increase reproductive fitness to various species responding to environmental pressures. Unlike animals, humans operate in shades of gray, with cultural taboos governing our behavior. While Freud believed these taboos prevent us from reverting to our animal past, evidence shows cultures unexposed to Western taboos developed their own rituals around cannibalism, often viewing it as honorable rather than forbidden.
Our fascination with cannibalism persists in popular culture through novels, films, TV shows like "The Walking Dead," and even our language. Though most cannibalism-related crimes stem from psychological aberrations, our desensitization to violence is troubling. More concerning is the potential for widespread cannibalism triggered by environmental collapse, as desertification and climate change threaten food security globally. Just as famine-related cannibalism occurred repeatedly throughout history, it could return with devastating consequences.
Since cannibalism is a normal response to severe stress during famine and warfare, widespread human butchery for food could become commonplace in drought-stricken, overpopulated regions. With accelerating climate change, nothing may prevent its return, especially in unstable countries. Beyond the horrific imagery, the consequences could include epidemic disease. Anthropologist Simon Underdown hypothesizes that TSEs may have contributed to Neanderthal extinction 30,000 years ago. His "Kuru Model" suggests that deaths from a kuru-like disease could have reduced Neanderthal populations to non-viable levels within 250 years, as the disease spread through cannibalistic practices.
The 1973 film "Soylent Green" depicts a dystopian 2022 New York City ravaged by climate change, pollution, and overpopulation, where most people survive on processed food wafers secretly made from human remains. While fictional, this scenario raises uncomfortable questions about how societies might respond to catastrophic food shortages. Despite medical advances, any future outbreaks of cannibalism-related TSEs could devastate local populations, as recent Ebola epidemics demonstrate.
As we face unprecedented environmental challenges, understanding cannibalism not as an aberration but as a predictable response to extreme conditions becomes increasingly important. By studying this taboo subject scientifically rather than sensationally, we gain valuable insights into both our evolutionary past and our uncertain future.
