110, no. Dixson, A. F. “Male Infanticide and Primate Monogamy.” Proceedings of the National Academy of Sciences, vol. A study into infanticide in langur monkeys has also shown that male attackers were not related to their infant victim and were likely the fathers of subsequent infants based on DNA analyses, further supporting the hypothesis. It is a rarely observed behaviour but some evidence for its occurrence in cetaceans exists in three species of dolphin. The Lion guardians are challenged by younger males looking for lionesses of their own. Both infanticide and the counter-strategies against can have their own costs. “Male Infanticide Leads to Social Monogamy in Primates.” Proceedings of the National Academy of Sciences, vol. , Infanticide by females other than the mother have been observed in wild groups of common marmosets (Callithrix jacchus).  Most cases of such behavior have been attributed to the resource competition hypothesis, in which females can gain more access to resources for herself and for her young by killing unrelated infants.  It is proposed that maternal infanticide occurs when the mother assesses the probability for infant survival based on previous infant deaths. Stable polymorphism in such behaviour could be maintained by negative frequency-dependent selection (benefit … Infanticide motivated by resource competition can occur both outside of and within familial groups. , To protect their young from infanticide, many species of primate mothers will form social monogamous pairs to prevent paternal infanticide.  Other female reproductive counter-strategies include but are not limited to concealed ovulation (paternity is obscured by the absence of reliable signals of ovulation and/or by variability in the timing of ovulation) and copulation with specific males (like those most likely to commit infanticide or more likely to protect the offspring). The adaptive significance of infanticide, if the behavior is considered adaptive for a population, most likely differs from population to population meaning the advantage of the strategy is multifarious, not unitary. The higher frequency in common marmosets may be due to a variety of social, reproductive, and ecological characteristics - including higher likelihood for overlapping pregnancies and births (due to short intervals between births), habitat saturation, and lower costs of infant care compared to other callitrichids - that increase the chance of two breeding females inhabiting the same group, leading to more intense competition. Rudolf, Volker H.w, and Janis Antonovics. Social relationships between males and females in primates are hypothesized to serve as protection against male infanticide. “The Evolution of Infanticide by Males in Mammalian Societies.” Science, vol. Palombit, Ryne A. PARTICIPANTS: Ronald J. Brooks (University of Guelph, Canada) Curt Busse (Emory University, USA) Carol Sue Carter …  Resource competition and sexual selection are ruled out because it is the mother that is performing the infanticide, not another female. Hrdy, Eds.) Series B: Biological Sciences, vol.  The females whose infants were killed exhibited estrous behavior and copulated with the new leader. Primate infanticide motivated by resource competition can also involve cannibalizing the infant as a source of nutrition.  Additionally, overcrowding or feeding competition were not factors in infanticide.  A female gorilla benefits more from protection by the silverback male, despite the fact that mating with only one male increased paternity certainty and thus increases the number of males in the population that would benefit reproductively from infanticide. Dominant, high ranking, female chimpanzees have been shown to more often aggress towards a lower ranking female and her infant due to resource competition. Culot, Laurence, et al. Male infanticide has been proposed to alter social evolution in mammals (and primates) by favoring female gregariousness or permanent male-female associations or by promoting a higher number of resident males that may help mothers to protect their infants from male intruders. Infanticide, the killing of the newborn.It has often been interpreted as a primitive method of birth control and a means of ridding a group of its weak and deformed children; but most societies actively desire children and put them to death (or allow them to die) only under exceptional circumstances. It has been estimated that infanticide occurs in 25% of all mammals and, in some of these populations, infanticide is a major contributor to infant mortality.. There are several ways this is accomplished including concealed ovulation. 110, no. 525–531., doi:10.1007/bf01068143. Sometimes, animals kill young members of their own social groups. What is infanticide?  However, complex interactions can arise when females have different social rankings and when resource availability is threatened. Infanticide is the killing of a child up to one year old, by a parent who has not fully recovered from pregnancy and who typically suffers from some degree of mental disturbance often associated with postpartum mental illness (Bourget & Labelle, 1992). Ramsden, Edmund. Cronus devours one of his sons by Peter Paul Rubens ( public domain ) The association between prophecy and infanticide is als… Recently, a male Leopard was photographed killing and eating a cub in the Okavango delta, Botswana. 266, no. Got it! , Resource competition is also a primary motivator in inter-species infanticide, or the killing of infants from one species by another species. Perrigo, Glenn, et al. Aldine, New York, 1984. , Social pathology: role of social organization, Adaptive counter adaptations to infanticide, CS1 maint: multiple names: authors list (, "Interspecific Infanticide and Infant-Directed Aggression by Spider Monkeys (Ateles hybridus) in a Fragmented Forest in Colombia", "Reproductive failure, possible maternal infanticide, and cannibalism in wild moustached tamarins, Saguinus mystax", "Infanticide and the evolution of pair bonds in nonhuman primates", 10.1002/(sici)1520-6505(1999)7:4<117::aid-evan2>3.0.co;2-o, "Infanticide risk and the evolution of male-female association in primates", "The adaptive value of 'friendships' to female baboons: experimental and observational evidence", "Male infanticide leads to social monogamy in primates", "Do gorilla females join males to avoid infanticide? Females in some primate species such as langur and gelada have also been known to terminate pregnancies to end investment in that offspring early after exposure to new replacement males through a process known as the Bruce effect.  The study also concludes that there is a sex difference in the genetic substrate that regulates the inheritance of infanticidal behavior. 1422, July 1999, pp. Forming this socially monogamous pair causes the males to form parental relationships and social bonds with the female's offspring. Opie, C., et al. “Prolonged Care and Cannibalism of Infant Corpse by Relatives in Semi-Free-Ranging Capuchin Monkeys.” Primates, Mar. 1–22., doi:10.1007/bf02557698. Infanticide in non-human primates occurs when an individual kills its own or another individual's dependent young. Callaway, Ewen. Infanticide (in animals) generally refers to the killing of an infant or a young offspring by an adult or mature individual of the same species and is observed in a variety of species ranging from humans to microscopic rotifers and especially in primates. Infanticide can also increase an animal’s reproductive success, by reducing competition for its offspring. WENNER-GREN FOUNDATION INTERNATIONAL SYMPOSIUM #88* August 16 - 22, 1982 Cornell University, Ithaca, New York. Further, females in the study were found to be motivated to form social bonds with males in order to protect them from infanticide. 13328–13332., doi:10.1073/pnas.1307903110. Borries, Carola, et al.  The hypothesis states that infanticide results from certain conditions created by human-induced disturbances or changes in nature.  Year-round association serves to lower the probability of infanticide by other males. Readings Art by Marcel Dzama, Read more. In this case, there were no clear functions of the infanticide; the reason for infanticide in black-fronted titi monkeys is currently unknown. Infanticide among animals is a widespread phenomenon with no unitary explanation. Infanticide, the killing of a young animal by an older animal, is performed by females and males that are unrelated to or are unfamiliar with the pups (see the section on kin recognition in Chapter 13). Trapanese, Cinzia, et al. In monogamous species, since pairs of reproducing adults live together with their offspring their whole lives, male infanticide of unrelated infants would not be as adaptive for individuals. Maternal infanticide differs from other varieties of infanticide in that the resource competition and sexual selection hypotheses (see other sections) must be rejected. 322–360., doi:10.1017/cbo9780511542312.016. “The Behavioral Genetics of Nonhuman Primates: Status and Prospects.” American Journal of Physical Anthropology, vol. This has been observed in wild geladas, where a majority of females abort pregnancies following the displacement of a dominant male.  Females in primate groups also kill or cannibalize infants although usually for motivations different from nutrition. , Females may also avoid the costs of continued reproductive investment when infanticide is likely. Infanticide can be an extreme result of sexual conflict that drives selection in species in which it occurs. 1–8., doi:10.1007/s10682-017-9925-0. Infanticide in one-male breeding units has also been observed in red-tailed monkeys and blue monkeys.  If it is unlikely that the infant will survive, infanticide may occur. “Counter-Strategies to Infanticide in Mammals: Costs and Consequences.” Oikos, vol.  Social disturbances such as overcrowding have been documented to have resulted in infanticide in rats , and similar factors may be at play in primate communities in which infanticide has been observed. Infanticide is the act of deliberately causing the death of a very young child (under 1 year old). When resources are limited, infants are easier to eliminate from the competition pool than other group members because they are the most defenseless and thus become targets of infanticide. The practice has been observed in many species throughout the animal kingdom, especially primates (primate infanticide). 32, no. Email address Sign Up. “The Evolution of Male Infanticide in Relation to Sexual Selection in Mammalian Carnivores.” Evolutionary Ecology, vol. Janson, Charles H., and Carel P. Van Schaik.  In addition, many primates live in multi-female groups, and it has been proposed that these females live together to reduce the risk of infanticide through paternity confusion or concealed ovulation. , In mammals, interaction between the sexes is usually limited to the female estrous or copulation.  Infants may also be used as protective buffers in primate groups during agonistic encounters (conflicts) between males which can result in the death of the infant. . 6, 1993, pp. In the animal kingdom, infanticide involves the killing of young offspring by a mature animal of its own species, and is studied in zoology, specifically in the field of ethology. 7, no. Infanticide is known to occur in many primate species, but is generally thought of as a male trait. “Infanticide as Sexual Conflict: Coevolution of Male Strategies and Female Counterstrategies.” Cold Spring Harbor Perspectives in Biology, vol. It has long been viewed … The most immediate and obvious form of protection against infanticide is physical defense wherein mothers either directly prevent aggressive acts toward their offspring or recruit other individuals for assistance.  Females in some primate species may form associations or coalitions with other females and with males to defend their offspring and reduce the risk of infanticide. 33, no. “Genetic Mediation of Infanticide and Parental Behavior in Male and Female Domestic and Wild Stock House Mice.” Behavior Genetics, vol. Timeless stories from our 170-year archive handpicked to speak to the news of the day. “DNA Analyses Support the Hypothesis That Infanticide Is Adaptive in Langur Monkeys.” Proceedings of the Royal Society of London. 335–339., doi:10.1016/j.beproc.2007.12.009. 40, no.  In addition to single male breeding groups, sexually selected infanticide often occurs in multi-male, multi-female breeding groups including the red howler and the mantled howler. Infanticide is common among India's lions, but females have developed a clever strategy to keep their cubs safe.  Adult Japanese macaque males were eight times more likely to attack infants when females had not mated with the male himself. Maternal infanticide has been reported once in brown mantled tamarins, Saguinus fuscicollis, once in black fronted titis, Callicebus nigrifrons, and four times in mustached tamarins, Saguinus mystax. Most often, dominant females opportunistically kill the young of a less dominant female when competition arises.. 2, Jan. 2009, pp. 6, 2015, doi:10.1101/cshperspect.a017640, Hrdy, Sarah Blaffer. This also allows sneak copulations in which non-dominant males sire offspring. Hrdy calls this “sexually selected infanticide.” “You hear me talk so cavalierly and casually about infanticide,” she says. Many primates such as the gorilla, chimpanzee, baboon, and langur have been known to practice infanticide while others, such as the orangutan, bonobo and mouse lemur have not been observed to do so. The benefits of infanticide for male non-human primates, and its costs to females, probably vary across mammalian social and mating systems  and between different primate species as well. “New Records of within-Group Infanticide and Cannibalism in Wild Chimpanzees.” Primates, vol.  Finally, in multi-male multi-female groups, female synchrony, in which females are all fertile at the same time, can prohibit the dominant male from monopolizing all of the females. Hamai, Miya, et al. In crowded populations of related mice and voles, infanticide is much more likely than it … "Before the 1970s, any type of infanticide in animals was considered pathological," says Craig Stanford, a primatologist at the University of Southern California in Los Angeles. , In some social systems, lower-ranking primate females may delay reproduction to avoid infanticide by dominant females, as seen in common marmosets. Five hypotheses have been proposed to explain infanticide in non-human primates: exploitation, resource competition, parental manipulation, sexual selection, and social pathology. 83, no. , In the instances of maternal infanticide in tamarins, there were multiple breeding females.  Filial infanticide, which can be accompanied by cannibalism (filial cannibalism), is widespread in fishes and is also seen in terrestrial animals.  This type of behavior has also been seen in the great apes such as bonobos and chimpanzees. Though it is not clear which genes are involved in primate infanticide, there is likely a genetic basis for the behavior that is yet to be discovered. Infanticide in non-human primates occurs as a result of exploitation when the individuals enacting the infanticide directly benefit from consumption or use of their victim. 1, 1984, pp. Feh, C., and B. Munkhtuya. This was the first ever photograph of a male leopard committing infanticide.  It is also important to consider that infanticide risk is low in solitary species, the ancestral mammalian social organization, and is unlikely to motivate evolutionary transitions from a solitary lifestyle to other social organizations. These strategies include physical defense, paternity confusion, reproduction suppression, and accelerated development. 3, 1998, p. 507., doi:10.2307/3546678. These bonds motivate males to defend their offspring against infanticide from unrelated individuals and to never commit infanticide against their own offspring.  This form of social monogamy has been observed in gibbons, siamangs, baboons, and macaques.. 346, no. “Hippy Apes Caught Cannibalising Their Young.” New Scientist, 1 Feb. 2010, https://www.upi.com/Science_News/2014/11/13/Big-testes-are-sign-that-a-species-has-history-of-infanticide/8601415916184/, https://www.newser.com/story/198646/why-25-of-mammals-commit-infanticide.html, https://science.sciencemag.org/content/346/6211/841. In animals, infanticide involves the killing of young offspring by a mature animal of the same species, and is studied in zoology, specifically in the field of ethology.  Adults of primate population often cannibalize the infant they kill, thereby gaining nutritive benefits from the action. Alas, infanticide has gone beyond mere advocacy in the modern world. Both males and females can be the perpetrators of infanticide in animals and both parents (filial infanticide) and non-parent individuals have been observed to display the behavior.Filial infanticide, which can be accompanied by cannibalism (filial cannibalism), i… 179–186., doi:10.1007/s10329-011-0238-6. 1, 1979, pp. One study demonstrated that for gorillas, living in harem-style groups reduces a female's risk of infanticide more than if she mated with multiple males.  In social primates such as baboons and macaques, the main role of male-male aggression may be to provide exclusive reproductive access to females and defend them and their young from stranger males.  This provides an advantage to the male because the female will more quickly copulate with him and raise his young rather than the young from the previous mate; his fitness increases through use of infanticide.  Another important situation in which paternity confusion can arise is when females mate with multiple males; this includes mating patterns such as polyandry and promiscuity in multi-male multi-female groups. , Resource competition results when there are too few resources in a particular area to support the existing population. Infanticide in general usage is defined as "the homicide of a person older than one week but less than one year of age." However, it is likely that antipredation is also a closely linked motivation to the formation of gorilla social units. This is known as the "aunting to death" phenomena; these non-lactating female primates gain mothering-like experience, yet lack the resources to feed the infant. Shannon Dawn Rayner of Charlottetown pleaded guilty to three counts of infanticide related to incidents in 2014, 2015 and 2016, as well as a charge of concealing a dead body. Infanticide (in animals) generally refers to the killing of an infant or a young offspring by an adult or mature individual of the same species and is observed in a variety of species ranging from humans to microscopic rotifers and especially in primates.