Cannibalism

Cannibalism is the act of one individual of a species consuming all or part of another individual of the same species as food. To consume the same species, or show cannibalistic behavior, is a common ecological interaction in the animal kingdom, and has been recorded for more than 1,500 species.[1] Human cannibalism is well-documented, both in ancient and recent times.[2]

The rate of cannibalism increases in nutritionally poor environments as individuals turn to other conspecific individuals as an additional food source.[3] Cannibalism regulates population numbers, whereby resources such as food, shelter and territory become more readily available with the decrease of potential competition. Although it may benefit the individual, it has been shown that the presence of cannibalism decreases the expected survival rate of the whole population and increases the risk of consuming a relative.[3] Other negative effects may include the increased risk of pathogen transmission as the encounter rate of hosts increases.[4] Cannibalism, however, does not—as once believed—occur only as a result of extreme food shortage or artificial/unnatural conditions, but could also occur under natural conditions in a variety of species.[1][5][6]

Cannibalism seems to be especially prevalent in aquatic ecosystems, in which up to approximately 90% of the organisms engage in cannibalistic activity at some point in their life cycle. Cannibalism is also not restricted to carnivorous species, as it can be found in herbivores and detritivores.[5] Sexual cannibalism normally involves the consumption of the male by the female individual before, during or after copulation.[3] Other forms of cannibalism include size-structured cannibalism and intrauterine cannibalism.

Behavioural, physiological and morphological adaptations have evolved to decrease the rate of cannibalism in individual species.[3]

Cannibalism on Tanna.jpeg
A cannibal feast in Vanuatu, Melanesia

Benefits

In environments where food availability is constrained, individuals can receive extra nutrition and energy if they use other conspecific individuals as an additional food source. This would, in turn, increase the survival rate of the cannibal and thus provide an evolutionary advantage in environments where food is scarce.[7] A study conducted on wood frog tadpoles showed that those that exhibited cannibalistic tendencies had faster growth rates and higher fitness levels than non-cannibals.[8] An increase of size and growth would give them the added benefit of protection from potential predators such as other cannibals and give them an advantage when competing for resources [3]

The nutritional benefits of cannibalism may allow for the more efficient conversion of a conspecific diet into reusable resources than fully herbaceous diet; as herbaceous diets may consist of excess elements which the animal has to expend energy to get rid of.[9] This facilitates for faster development; however, a trade-off may occur as there may be less time to ingest these acquired resources. Studies have shown that there is a noticeable size difference between animals fed on a high conspecific diet which were smaller compared to those fed on a low conspecific diet.[9] Hence, individual fitness could only be increased if the balance between developmental rate and size is balanced out, with studies showing that this is achieved in low conspecific diets.[9]

Cannibalism regulates population numbers and benefits the cannibalistic individual and its kin as resources such as extra shelter, territory and food are freed; thereby increasing the fitness of the cannibal;[7] by lowering crowding effects.[10] However, this is only the case if the cannibal recognizes its own kin as this won't hinder any future chances of perpetuating its genes in future generations. The elimination of competition can also increase mating opportunities, allowing further spread of an individual's genes.

Costs

Animals which have diets consisting of predominantly conspecific prey expose themselves to a greater risk of injury and expend more energy foraging for suitable prey as compared to non-cannibalistic species. [3]

In order to combat the risk of personal injury, a predator often targets younger or more vulnerable prey. However, the time necessitated by such selective predation could result in a failure to meet the predator's self-set nutritional requirements.[11] In addition, the consumption of conspecific prey may also involve the ingestion of defense compounds and hormones, which have the capacity to impact the developmental growth of the cannibal's offspring[9] Hence, predators normally partake in a cannibalistic diet in conditions where alternative food sources are absent or not as readily available.

Failure to recognize kin prey is also a disadvantage, provided cannibals target and consume younger individuals. For example, a male stickleback fish may often mistake their own "eggs" for their competitor's eggs, and hence would inadvertently eliminate some of its own genes from the available gene pool.[3] Kin recognition has been observed in tadpoles of the spadefoot toad, whereby cannibalistic tadpoles of the same clutch tended to avoid consuming and harming siblings, while eating other non-siblings.[12]

The act of cannibalism may also facilitate trophic disease transmission within a population, though cannibalistically spread pathogens and parasites generally employ alternative modes of infection.[4]

Diseases transmitted through cannibalism

Cannibalism can potentially reduce the prevalence of parasites in the population by decreasing the number of susceptible hosts and indirectly killing the parasite in the host.[13] It has been shown in some studies that the risk of encountering an infected victim increases when there is a higher cannibalism rate, though this risk drops as the number of available hosts decreases.[13] However, this is only the case if the risk of disease transmission is low.[4] Cannibalism is an ineffective method of disease spread as cannibalism in the animal kingdom is normally a one-on-one interaction, and the spread of disease requires group cannibalism; thereby it is rare for a disease to have evolved to rely solely on cannibalism to spread. Usually there are different means of transmission, such as with direct contact, maternal transmission, coprophagy, and necrophagy with different species.[4] Infected individuals are more likely to be consumed than non-infected individuals, thus some research has suggested that the spread of disease may be a limiting factor to the prevalence of cannibalism in the population.[13]

Some examples of diseases transmitted by cannibalism in mammals include Kuru which is a prion disease that degenerates the brain.[4] This disease was prevalent in Papua New Guinea whereby tribes practiced endocannibalism in cannibalistic funeral rituals and consume the brains infected by these prions.[14] It is a cerebellar dysfunctional disease which has symptoms including a broad-based gait and decreased motor activity control; however, the disease has a long incubation rate and symptoms may not appear until years later.[14]

Bovine spongiform encephalopathy, or mad cow disease is another prion disease which is usually caused by feeding contaminated bovine tissue to other cattle.[15] It is a neurodegenerative disease and could be spread to humans if the individual were to consume contaminated beef. The spread of parasites such as nematodes may also be facilitated by cannibalism as eggs from these parasites are transferred more easily from one host to another.[4]

Other forms of diseases include sarcocystis and iridovirus in reptiles and amphibians; granulosus virus, chagas disease, and microsporidia in insects; stained prawn disease, white pot syndrome, helminthes and tapeworms in crustaceans and fish.[4]

Foraging dynamics

Cannibalism may become apparent when direct competition for limited resources forces individuals to use other conspecific individuals as an additional resource to maintain their metabolic rates.[3] Hunger drives individuals to increase their foraging rates, which in turn decreases their attack threshold and tolerance to other conspecific individuals. As resources dwindle, individuals are forced to change their behaviour which may lead to animal migration,[16] confrontation, or cannibalism.[3]

Cannibalism rates increase with increasing population density as it becomes more advantageous to prey on conspecific organisms than to forage in the environment.[3] This is because the encounter rate between predator and prey increases, making cannibalism more convenient and beneficial than foraging within the environment. Over time, the dynamics within the population changes as those with cannibalistic tendencies may receive additional nutritional benefits and increase the size ratio of predator to prey.[17] The presence of smaller prey, or prey which are at a vulnerable stage of their life cycle, increases the chances of cannibalism occurring due to the reduced risk of injury.[18] A feedback loop occurs when increasing rates of cannibalism decreases population densities, leading to an increased abundance of alternative food sources; making it more beneficial to forage within the environment than for cannibalism to occur.[3] When population numbers and foraging rates increase, the carrying capacity for that resource in the area may be reached, thus forcing individuals to look for other resources such as conspecific prey.

Sexual cannibalism

Sexual cannibalism is present largely in spiders and other invertebrates, including gastropods.[3] This refers to the killing and consumption of conspecific sexual partners during courtship, and during or after copulation. Normally, it is the female which consumes the conspecific male organism, though there have been some reported cases of the male consuming the adult female, however, this has only been recorded under laboratory conditions.[3][19][20] Sexual cannibalism has been recorded in the female redback spider, black widow spider, praying mantis, and scorpion, among others.

In most species of spiders, the consumption of the male individual occurs before copulation and the male fails to transfer his sperm into the female.[3] This may be due to mistaken identity such as in the case of the orb weaving spider which holds little tolerance to any spider which are present in its web and may mistake the vibrations to be that of a prey item.[3] Other reasons for male consumption before mating may include female choice and the nutritional advantages of cannibalism.[21] The size of the male spider may play a part in determining its reproductive success as smaller males are less likely to be consumed during pre-copulation; however, larger males may be able to prevent the smaller ones from gaining access to the female.[21] There exists a conflict of interest between males and females, as females may be more inclined to turn to cannibalism as a source of nutritional intake while the male's interest is mostly focused on ensuring paternity of the future generations.[3] It was found that cannibalistic females produced offspring with greater survival rates than non-cannibalistic females, as cannibals produced greater clutches and larger egg sizes.[22] Hence, species such as the male dark fishing spider of the family dolomedes self-sacrifice and spontaneously die during copulation to facilitate their own consumption by the female, thereby increasing the chance of survivorship of future offspring.[23]

Sexual dimorphism has been theorised to have arisen from sexual selection as smaller males were captured more easily than larger males; however, it is also possible that sexual cannibalism only occurs due to the difference in size between male and females.[3] Data comparing female and male spider body length shows that there is little support for the prior theory as there is not much correlation between body size and the presence of sexual cannibalism. Not all species of spiders which partake in sexual cannibalism exhibit size dimorphism.[3]

The avoidance of sexual cannibalism is present in many male species to increase their rate of survival, whereby the male uses cautionary methods to lower the risk of his consumption.[3] Male orb weaving spiders would often wait for females to moult or to finish eating before attempting to initiate mating, as the females are less likely to attack.[3] Males which are vulnerable to post copulation consumption may gather mating thread to generate a mechanical tension which they could use to spring away after insemination, while other spiders such as the crab spider may tangle the female legs in webs to reduce the risk of the female capturing him.[3] Male choice is common in mantids whereby males were observed to choose fatter females due to the reduced risk of attack and were more hesitant to approach starved females.[24]

Size-structured cannibalism

Mononchidae eating a Mononchidae 1
Nematode Mononchidae eating another Mononchidae.

Size-structured cannibalism is cannibalism in which older, larger, more mature individuals consume smaller, younger conspecifics. In size-structured populations, (where populations are made of individuals of various sizes, ages, and maturities), cannibalism can be responsible for 8% (Belding's ground squirrel) to 95% (dragonfly larvae) of the total mortality,[25] making it a significant and important factor for population[26] and community dynamics.[27]

Size-structured cannibalism has commonly been observed in the wild for a variety of taxa. Vertebrate examples include chimpanzees, where groups of adult males have been observed to attack and consume infants.[28][29][30]

Filial cannibalism

Filial cannibalism is a specific type of size-structured cannibalism in which adults eat their own offspring.[31] Although most often thought of as parents eating live young, filial cannibalism includes parental consumption of stillborn infants and miscarried fetuses as well as infertile and still-incubating eggs. Vertebrate examples include pigs, where savaging accounts for a sizable percentage of total piglet deaths, and cats.[32]

Filial cannibalism is particularly common in teleost fishes, appearing in at least seventeen different families of teleosts.[33] Within this diverse group of fish, there have been many, variable explanations of the possible adaptive value of filial cannibalism. One of these is the energy-based hypothesis, which suggests that fish eat their offspring when they are low on energy as an investment in future reproductive success.[31] This has been supported by experimental evidence, showing that male three-spined sticklebacks,[31][34][35] male tessellated darters,[36] and male sphinx blenny fish[37] all consume or absorb their own eggs to maintain their physical conditions. In other words, when males of a fish species are low on energy, it might sometimes be beneficial for them to feed on their own offspring to survive and invest in future reproductive success.

Another hypothesis as to the adaptive value of filial cannibalism in teleosts is that it increases density-dependent egg survivorship. In other words, filial cannibalism simply increases overall reproductive success by helping the other eggs make it to maturity by thinning out the numbers. Possible explanations as to why this is so include increasing oxygen availability to the remaining eggs,[38] the negative effects of accumulating embryo waste,[39] and predation.[39]

In some species of eusocial wasps, such as Polistes chinensis, the reproducing female will kill and feed younger larvae to her older brood. This occurs under food stressed conditions in order to ensure that the first generation of workers emerges without delay.[40] Further evidence also suggests that occasionally filial cannibalism might be the unfortunate by-product of cuckoldry in fish. Males consume broods, which may include their own offspring, when they believe a certain percentage of the brood contains genetic material that is not theirs.[34][41]

The dinosaur Coelophysis was once suspected to practice this form of cannibalism but this turned out to be wrong, although Deinonychus may have done. Skeletal remains from subadults with missing parts are suspected of having been eaten by other Deinonychus, mainly full-grown adults.

Infanticide

Infanticide is the killing of a non-adult animal by an adult of the same species. Infanticide is often, but not always, accompanied by cannibalism. It is often displayed in lions; a male lion encroaching on the territory of a rival pride will often kill any existing cubs fathered by other males; this brings the lionesses into heat more quickly, enabling the invading lion to sire his own young. This is a good example of cannibalistic behavior in a genetic context.

In many species of Lepidoptera, such as Cupido minimus and the Indian mealmoth, the first larvae to hatch will consume the other eggs or smaller larvae on the host plant to decrease competition.[42][43]

Intrauterine cannibalism

Intrauterine cannibalism is a behaviour in some carnivorous species, in which multiple embryos are created at impregnation, but only one or two are born. The larger or stronger ones consume their less-developed siblings as a source of nutrients.

In adelphophagy or embryophagy, the fetus eats sibling embryos, while in oophagy it feeds on eggs.[44][45]

Adelphophagy occurs in some marine gastropods (calyptraeids, muricids, vermetids, and buccinids) and in some marine annelids (Boccardia proboscidia in Spionidae).[46]

Intrauterine cannibalism is known to occur in lamnoid sharks[47] such as the sand tiger shark, and in the fire salamander,[48] as well as in some teleost fishes.[45] The Carboniferous period chimaera, Delphyodontos dacriformes, is suspected of having practiced intrauterine cannibalism, also, due to the sharp teeth of the recently born (or possibly aborted) juveniles, and the presence of fecal matter in the juveniles' intestines.[49]

Protection against cannibalism

Animals have evolved protection to prevent and deter potential predators such as those from their own kind.[3] Many amphibian eggs are gelatinous and toxic to decrease edibility. Often, adults would lay their eggs in crevices, holes, or empty nesting sites to hide their eggs from potential conspecific predators which tend to ingest the eggs for an additional nutritional benefit or to get rid of genetic competition. In amphibians, the development of non-aquatic egg deposition has helped increase the survival rates of their young by the evolution of viviparity or direct development.[3] In bees, worker policing occurs to prohibit worker reproduction, whereby workers cannibalize other worker laid eggs.[50] Queen laid eggs have a different scent than worker laid eggs, allowing workers differentiate between the two, allowing them to nurture and protect queen laid eggs rather than cannibalising them.[50] Parental presence at nesting sites is also a common method of protection against infanticide committed by conspecific individuals, whereby the parent exhibit defensive displays to ward off potential predators. Parental investment in newborns are generally higher during their early stages of development whereby behaviours such as aggression, territorial behaviour, and pregnancy blocking become more apparent.[3]

Morphological plasticity helps an individual account for different predation stresses, thereby increasing individual survival rates.[51] Japanese brown frog tadpoles have been shown to exhibit morphological plasticity when they are in a high stress environment where cannibalism between tadpoles and more developed individuals were present. Shifting their morphology plays a key role in their survival, creating bulkier bodies when put into environments where more developed tadpoles were present, to make it difficult for the individuals to swallow them whole.[51] Diet shifts between different stages of development have also evolved to decrease competition between each stage, thereby increasing the amount of food availability so that there is a decreased chance that the individuals will turn to cannibalism as an additional food source.[3]

See also

References

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Further reading

  • M. A. Elgar and Bernard J. Crespi (eds.). 1992. Cannibalism: Ecology and Evolution of Cannibalism among Diverse Taxa Oxford University Press, New York. (361pp) ISBN 0-19-854650-5
Abnormal behaviour of birds in captivity

Abnormal behavior of birds in captivity can be defined in several ways. Statistically, 'abnormal' is when the occurrence, frequency or intensity of a behaviour varies statistically significantly, either more or less, from the normal value. This means that theoretically, almost any behaviour could become 'abnormal' in an individual. Less formally, 'abnormal' includes any activity judged to be outside the normal behaviour pattern for captive birds of that particular class or age. For example, running rather than flying may be a normal behaviour and regularly observed in one species, however, in another species it might be normal but becomes 'abnormal' if it reaches a high frequency, or in another species it is rarely observed and any incidence is considered 'abnormal'. This article does not include 'one-off' behaviours performed by individual birds that might be considered abnormal for that individual, unless these are performed repeatedly by other individuals in the species and are recognised as part of the ethogram of that species.

Most abnormal behaviours can be categorised collectively (e.g., eliminative, ingestive, stereotypies), however, many abnormal behaviours fall debatebly into several of these categories and categorisation is therefore not attempted in this article. Abnormal behaviours here are considered to be related to captive housing but may also be due to medical conditions. The article does not include behaviours in birds that are genetically modified to express abnormal behaviour.

When housed under captive or commercial conditions, birds often show a range of abnormal behaviours. These are often self-injurious or harmful to other individuals, and include:

Feather pecking

Cannibalism

Vent pecking

Toe pecking

Feather plucking

Stereotypies

Polydipsia

Sham or "vacuum" dustbathing

Jealous, over-possessive parrot

Chronic egg layingWhen analyzing the behaviour of birds in captivity, what is considered normal or abnormal behaviour is dependent on the form and frequency that the particular behaviour is expressed in the natural environment. Birds raised in pet stores tend to be raised with other birds, however, after being sold and taken to the owner's home, birds in captivity are often housed in isolation and in environments lacking abundant resources or complex stimuli. In the United States, it is estimated that forty million birds are kept caged and improperly cared for. Because of these inappropriate housing conditions, abnormal behaviour patterns may appear in caged birds kept as pets. Once established, these abnormal behaviours in birds are often not alterable.When social interactions amongst birds are absent or inadequate, abnormal social behaviour may develop. For example, a study regarding parrots that had been isolated in cages demonstrated that most birds showing this social deprivation had significant behavioural disturbances, such as aggressive behaviour, feather picking, self-mutilation, restlessness, screaming, apathetic behavior, and stereotypies. Cannibalism often occurs in large animal husbandry systems, which are usually impoverished environments with a lack of opportunities. In addition, studies of caged canaries have revealed two common stereotypies. These include spot picking, where birds repeatedly touch a particular spot in the environment with the tip of their beak, and route tracing, a pacing behaviour associated with physical restrictions in movement imposed by the cage. The absence of song learning in zebra finches has also been implicated as a behavioural abnormality. In these birds, the social interaction of a young male with his song tutor is important for normal song development. Without the stimulus, the song, which is necessary for mating behavior, will not be learned.

Researchers have analyzed ways to alleviate some abnormal behaviours in caged birds. Presenting these birds with novel stimuli e.g. a mirror or plastic birds, and social stimuli, such as a brief view of a bird in another cage, significantly reduced stereotypies. In addition, it has been suggested that keeping caged birds in pairs or small groups may reduce the development of abnormal behaviours, however, little quantitative evidence has thus far been collected to support this claim.

Debeaking

Debeaking is the partial removal of the beak of poultry, especially layer hens and turkeys although it may also be performed on quail and ducks. Most commonly, the beak is shortened permanently, although regrowth can occur. The trimmed lower beak is somewhat longer than the upper beak.

Beak trimming is most common in egg-laying strains of chickens. In some countries, such as the United States, turkeys routinely have their beaks trimmed. In the UK, only 10% of turkeys are beak trimmed. Beak trimming is a preventive measure to reduce damage caused by injurious pecking such as cannibalism, feather pecking and vent pecking, and thereby improve livability. Commercial broiler chickens are not routinely beak trimmed as they reach slaughter weight at approximately 6 weeks of age, i.e. before injurious pecking usually begins. However, broiler breeding stock may be trimmed to prevent damage during mating. In some countries, beak trimming is done as a last resort where alternatives are considered not to be possible or appropriate.

Opponents of beak trimming state that the practice reduces problem pecking by minor amounts compared to the trauma, injury, and harm done to the entire flock by beak trimming. Reduction is in single digit percentiles, whereas improvement of conditions especially in layer colonies will cease problematic behavior entirely.Beak trimming has been banned in Switzerland since 1992 and has been phased out in Germany in 2017.In close confinement, cannibalism, feather pecking and aggression are common among turkeys, ducks, pheasants, quail, and chickens of many breeds (including both heritage breeds and modern hybrids) kept for eggs. The tendency to cannibalism and feather pecking varies among different strains of chickens, but does not manifest itself consistently. Some flocks of the same breed may be entirely free from cannibalism, while others, under the same management, may have a serious outbreak. Mortalities, mainly due to cannibalism, can be up to 15% in egg laying flocks housed in aviaries, straw yards, and free-range systems.Because egg laying strains of chickens can be kept in smaller group sizes in caged systems, cannibalism is reduced leading to a lowered trend in mortality as compared to non-cage systems. Cannibalism among flocks is highly variable and when it is not problematic, then mortalities among production systems are similar.

Fontbrégoua Cave

Fontbrégoua Cave is an archaeological site located in Provence, Southeastern France. It was used by humans in the fifth and fourth millennia BCE, in what is now known as the Early and Middle Neolithic. A temporary residential site, it was used by Neolithic agriculturalists as a storage area for their herds of goats and sheep, and also contained a number of bone depositions, containing the remains of domestic species, wild animals, and humans. The inclusion of the latter of these deposits led the archaeological team studying the site to propose that cannibalism had taken place at Fontbrégoua, although other archaeologists have instead suggested that they represent evidence of secondary burial.

The original excavators of the site, under the leadership of Paola Villa, argued that the treatment of human remains at the site constituted strong evidence of cannibalism. This conclusion was criticised by M.P. Pickering, who instead suggested that the evidence was better explained by defleshing rituals involved in secondary burial, drawing ethnographic comparisons with certain Indigenous Australian practices. Pickering's views were supported by the archaeologist Paul Bahn, but in turn came under counter-criticisms from Villa.

Gough's Cave

Gough's Cave is located in Cheddar Gorge on the Mendip Hills, in Cheddar, Somerset, England. The cave is 115 m (377 ft) deep and is 3.405 km (2.12 mi) long,

and contains a variety of large chambers and rock formations. It contains the Cheddar Yeo, the largest underground river system in Britain.

Human cannibalism

Human cannibalism is the act or practice of humans eating the flesh or internal organs of other human beings. A person who practices cannibalism is called a cannibal. The expression cannibalism has been extended into zoology to mean one individual of a species consuming all or part of another individual of the same species as food, including sexual cannibalism. Some scholars have argued, however, that no firm evidence exists that cannibalism has ever been a socially acceptable practice anywhere in the world, at any time in history.The Island Carib people of the Lesser Antilles, from whom the word cannibalism is derived, acquired a long-standing reputation as cannibals following the recording of their legends in the 17th century. Some controversy exists over the accuracy of these legends and the prevalence of actual cannibalism in the culture. Cannibalism was practiced in New Guinea and in parts of the Solomon Islands, and flesh markets existed in some parts of Melanesia. Fiji was once known as the "Cannibal Isles". Cannibalism has been well documented around the world, from Fiji to the Amazon Basin to the Congo to the Māori people of New Zealand. Neanderthals are believed to have practiced cannibalism, and Neanderthals may have been eaten by anatomically modern humans. Cannibalism was also practiced in the past in Egypt during ancient Egypt, Roman Egypt and during famines such as the great famine in the year 1201.Cannibalism has recently been both practiced and fiercely condemned in several wars, especially in Liberia and the Democratic Republic of the Congo. It was still practiced in Papua New Guinea as of 2012, for cultural reasons and in ritual and in war in various Melanesian tribes. Cannibalism has been said to test the bounds of cultural relativism because it challenges anthropologists "to define what is or is not beyond the pale of acceptable human behavior".Cannibalism has occasionally been practiced as a last resort by people suffering from famine, even in modern times. Famous examples include the ill-fated Donner Party (1846–47) and, more recently, the crash of Uruguayan Air Force Flight 571 (1972), after which some survivors ate the bodies of dead passengers. Also, some mentally ill people have done so, such as Jeffrey Dahmer and Albert Fish. There is resistance to formally labeling cannibalism a mental disorder.

Interacting galaxy

Interacting galaxies (colliding galaxies) are galaxies whose gravitational fields result in a disturbance of one another. An example of a minor interaction is a satellite galaxy's disturbing the primary galaxy's spiral arms. An example of a major interaction is a galactic collision, which may lead to a galaxy merger.

Island Caribs

The Island Carib, also known as the Kalinago or simply Caribs, are an indigenous people of the Lesser Antilles in the Caribbean. They have descended from the Mainland Caribs (Kalina) of South America as well as the Arawakan people of the Greater Antilles. The women and children spoke an Arawakan language known as Eyeri.Meanwhile the men spoke a language of Karina origins.At the time of Spanish contact, the Kalinagos were one of the dominant groups in the Caribbean, which owes its name to them. They lived throughout the Windward Islands, Dominica, and possibly the southern Leeward Islands. Historically, it was thought their ancestors were mainland Caribs, known as the Igneri. The Igneri had conquered the islands from their previous inhabitants. However, linguistic and archaeological evidence disputes the notion of a mass emigration and conquest; the Island Carib language appears not to have been Cariban, but Arawakan, like that of their neighbors, the Taíno. Irving Rouse and others suggest that a smaller group of mainland Caribs conquered the islands without displacing their inhabitants, eventually adopting the local language but retaining their traditions of a South American origin.In the early colonial period, the Caribs had a reputation as warriors who raided neighboring islands. They practiced cannibalism. According to the Spanish conquistadores, the Carib Indians were cannibals who regularly ate roasted human flesh. There is evidence as to the taking of human trophies and the ritual cannibalism of war captives among both Carib and other Amerindian groups such as the Arawak and Tupinamba. Today, the Caribs and their descendants continue to live in the Antilles. The Garifuna or "Black Caribs", a group of mixed Carib and African ancestry, also live principally in Central America.

Kuru (disease)

Kuru is a very rare, incurable and invariably fatal neurodegenerative disorder that was formerly common among the Fore people of Papua New Guinea. Kuru is caused by the transmission of abnormally folded proteins (prion proteins), which leads to symptoms such as tremors, loss of coordination, and neurodegeneration.

The term kuru derives from the Fore word kuria or guria ("to shake"), due to the body tremors that are a classic symptom of the disease and kúru itself means "trembling". It is also known as the "laughing sickness" due to the pathologic bursts of laughter which are a symptom of the disease. It is now widely accepted that kuru was transmitted among members of the Fore tribe of Papua New Guinea via funerary cannibalism. Deceased family members were traditionally cooked and eaten, which was thought to help free the spirit of the dead. Women and children usually consumed the brain, the organ in which infectious prions were most concentrated, thus allowing for transmission of kuru. The disease was therefore more prevalent among women and children.

The epidemic likely started when a villager developed sporadic Creutzfeldt–Jakob disease and died. When villagers ate the brain, they caught the disease, and it was then spread to other villagers that ate their infected brains.While the Fore people stopped eating human meat in the early 1960s, when it was first speculated to be transmitted via endocannibalism, the disease lingered due to kuru's long incubation period of anywhere from 10 to over 50 years. The epidemic declined sharply after discarding cannibalism, from 200 deaths per year in 1957 to 1 or no deaths annually in 2005, with sources disagreeing on whether the last known kuru victim died in 2005 or 2009.

Lady Franklin Bay Expedition

The 1881–1884 Lady Franklin Bay Expedition (officially the International Polar Expedition) into the Canadian Arctic was led by Lt. Adolphus Greely and was promoted by the United States Army Signal Corps. Its purpose was to establish a meteorological-observation station as part of the First International Polar Year, and to collect astronomical and magnetic data. During the expedition, two members of the crew reached a new "Farthest North" record, but of the original twenty-five men only seven survived to return to the United States.

The expedition was under the auspices of the Signal Corps at a time when the Corps' Chief Disbursements Officer, Henry W. Howgate, was arrested for embezzlement. However, that did not deter the planning and execution of the voyage.

Lifeboat sketch

Monty Python's Lifeboat (Cannibalism) sketch appeared on Monty Python's Flying Circus in Episode 26. It was also performed on the album, Another Monty Python Record, retitled "Still No Sign Of Land". The sketch was inspired by the famous 1884 English criminal law case of R v Dudley and Stephens which involved survival cannibalism among castaways after a shipwreck.The sketch features five sailors in a lifeboat, and features several resets where the characters mess up their lines and the whole sketch has to be restarted. The characters, trapped on the lifeboat and starving, decide to resort to cannibalism.

The Captain volunteers himself as victim, but is snubbed by two sailors, who are put off by the Captain's "gammy leg" and who would rather eat the flattered Johnson. All the sailors then begin bickering about who should be eaten first, on the grounds of who's too lean, not kosher, etc.

The argument ends with the planned menu: "Look. I tell you what. Those who want to can eat Johnson. And you, sir, can have my leg. And we make some stock from the Captain, and then we'll have Johnson cold for supper." As a nice addition to the meal, they then conjure up avocados and canned peaches, and call a waitress to their boat to take their order, followed by the studio audience booing.

The sketch is followed by the announcer reading a letter to the editor saying, "Dear Sir, I am glad to hear that your studio audience disapproves of the last skit as strongly as I. As a naval officer I abhor the implication that the Royal Navy is a haven for cannibalism. It is well known that we have the problem relatively under control, and that it is the R.A.F. who now suffer the largest casualties in this area. And what do you think the Argylls ate in Aden? Arabs? Yours etc. Captain B. J. Smethwick in a white wine sauce with shallots, mushrooms and garlic."The letter is followed by a highly cannibalistic Terry Gilliam animated cartoon, a brief plea for decency from Terry Jones in a false moustache, and finally the equally offensive "Undertakers sketch".

List of feeding behaviours

Feeding is the process by which organisms, typically animals, obtain food. Terminology often uses either the suffixes -vore, -vory, -vorous from Latin vorare, meaning "to devour", or -phage, -phagy, -phagous from Greek φαγειν (phagein), meaning "to eat".

Mantis

Mantises are an order (Mantodea) of insects that contains over 2,400 species in about 430 genera in 15 families. The largest family is the Mantidae ("mantids"). Mantises are distributed worldwide in temperate and tropical habitats. They have triangular heads with bulging eyes supported on flexible necks. Their elongated bodies may or may not have wings, but all Mantodea have forelegs that are greatly enlarged and adapted for catching and gripping prey; their upright posture, while remaining stationary with forearms folded, has led to the common name praying mantis.

The closest relatives of mantises are the termites and cockroaches (Blattodea), which are all within the superorder Dictyoptera. Mantises are sometimes confused with stick insects (Phasmatodea), other elongated insects such as grasshoppers (Orthoptera), or other unrelated insects with raptorial forelegs such as mantisflies (Mantispidae). Mantises are mostly ambush predators, but a few ground-dwelling species are found actively pursuing their prey. They normally live for about a year. In cooler climates, the adults lay eggs in autumn, then die. The eggs are protected by their hard capsules and hatch in the spring. Females sometimes practice sexual cannibalism, eating their mates after copulation.

Mantises were considered to have supernatural powers by early civilizations, including Ancient Greece, Ancient Egypt, and Assyria. A cultural trope popular in cartoons imagines the female mantis as a femme fatale. Mantises are among the insects most commonly kept as pets.

Miami cannibal attack

On May 26, 2012, a nude assailant, Rudy Eugene, attacked and maimed Ronald Poppo, a homeless man, on the MacArthur Causeway in Miami, Florida, making headlines worldwide. During the 18-minute filmed encounter, Eugene accused Poppo of stealing his Bible, beat him unconscious, removed Poppo's pants, and bit off most of Poppo's face above the beard (including his left eye), leaving him blind in both eyes. As a result of the incident's shocking nature and subsequent worldwide media coverage, Eugene came to be dubbed the "Miami Zombie" and the "Causeway Cannibal". The attack ended when Eugene was fatally shot by a Miami PD officer.

Although friends and family filled in details of Eugene's life, the reason for the attack remains unclear. Eugene, 31, employed at a car wash at the time, was a divorced former high school football player with a series of petty criminal arrests from age 16, with the last in 2009. Poppo, 65, a graduate of Manhattan's Stuyvesant High School, was homeless and had long been presumed dead by his estranged family. While police sources speculated that the use of a street drug like "bath salts" might have been a factor, experts expressed doubt, since toxicology reports were only able to identify marijuana in Eugene's system, leaving the ultimate cause of his behavior unknown.

Sawi people

The Sawi or Sawuy are a tribal people of Western New Guinea, Indonesia. They were known to be cannibalistic headhunters as recently as the 1950s.

Since then, many of the tribe have converted to Christianity and the world's largest circular building made strictly from un-milled poles was constructed in 1972 as a Christian meeting place by the Sawi. Christian missionary Don Richardson who lived among the Sawi wrote a book about the experience called Peace Child.

Self-cannibalism

Self-cannibalism is the practice of eating oneself, also called autocannibalism, or autosarcophagy. A similar term which is applied differently is autophagy, which specifically denotes the normal process of self-degradation by cells. While almost an exclusive term for this process, autophagy nonetheless has occasionally made its way into more common usage.

Sexual cannibalism

Sexual cannibalism is when a female cannibalizes her mate prior to, during, or after copulation. It is a phenomenon characterized primarily by members of most arachnid orders, as well as several insect orders. The adaptive foraging hypothesis, aggressive spillover hypothesis and mistaken identity hypothesis are among the proposed theories to explain how sexual cannibalism evolved. This behavior is believed to have evolved as a manifestation of sexual conflict, occurring when the reproductive interests of males and females differ. In many species that exhibit sexual cannibalism, the female consumes the male upon detection. Females of cannibalistic species are generally hostile and unwilling to mate; thus many males of these species have developed adaptive behaviors to counteract female aggression.

Splatter film

A splatter film is a subgenre of horror film that deliberately focuses on graphic portrayals of gore and graphic violence. These films, usually through the use of special effects, display a fascination with the vulnerability of the human body and the theatricality of its mutilation. The term "splatter cinema" was coined by George A. Romero to describe his film Dawn of the Dead, though Dawn of the Dead is generally considered by critics to have higher aspirations, such as social commentary, than to be simply exploitative for its own sake.During the late 20th and early 21st centuries, the use of graphic violence in cinema has been labeled "torture porn" or "gorno" (a portmanteau of "gore" and "porno"). By contrast, films such as Braindead, Evil Dead II and to some extent Dawn of the Dead, all of which feature over-the-top gore, can be construed as comedic, and fall into the category of splatstick.

Vorarephilia

Vorarephilia (often shortened to vore) is a paraphilia characterized by the erotic desire to be consumed by, or sometimes to personally consume, another person or creature, or an erotic attraction to the process of eating in general practice. Since vorarephilic fantasies cannot usually be acted out in reality, they are often expressed in stories or drawings shared on the Internet. The word vorarephilia is derived from the Latin vorare (to "swallow" or "devour"), and Ancient Greek φιλία (philía, "love").

The fantasy usually involves the victim being swallowed whole, though occasionally the victims are chewed up, and digestion may or may not be included. Vore fantasies are separated from sexual cannibalism because the living victim is normally swallowed whole. Sometimes the consumers are human, but anthropormorphized animals, normal animals, dragons, and enormous snakes also appear frequently in these fantasies. After consumption, the enlarged belly of the consumer is often described with great care. Vorarephiles sometimes prefer to differentiate between soft vore and hard vore; soft vore means the victim is swallowed whole and alive, and may possibly come back out in the case of a "non-fatal" scenario, while in hard vore the victim goes through a more gruesome, realistic digestion process, often getting chewed up beforehand.

Vore is most often enjoyed through pictures, stories, videos, and video games, and it can appear in mainstream media. In some cases, vorarephilia may be described as a variation of macrophilia and may combine with other paraphilias. Apart from macrophilia, vore fantasies often have themes of BDSM, microphilia, pregnancy fetishism, furry fetishism, "unbirthing" (a desire to be swallowed whole into the vagina and returned to the uterus), and sexual cannibalism.One case study analysis connected the fantasy with sexual masochism, and suggested that it could be motivated by a desire to merge with a powerful other or permanently escape loneliness. With "no known treatment" for vorarephiles who feel ill at ease with their sexuality, psychologists at Toronto's Centre for Addiction and Mental Health have recommended trying to "adjust to, rather than change or suppress" the sexual interest. Medication for libido reduction could be used if deemed necessary.

Wari’

The Wari', also known as the Pakaa Nova, are an indigenous people of Brazil, living in seven villages in the Amazon rainforest in the state of Rondônia. Their first contact with European settlers was on the shores of the Pakaa Nova River, a tributary of the Mamoré River. Many of them live within the Sagarana Indigenous Territory.

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