Why Don't Male Animals "Protect" Themselves From The Female Of Their Species?

Killing of immature offspring by an adult brute of the same species

King of beasts cubs may be killed by males replacing other males in the pride.^[1]

In animals, infanticide involves the killing of young offspring past a mature fauna of the same species, and is studied in zoology, specifically in the field of ethology. Ovicide is the coordinating destruction of eggs. The practice has been observed in many species throughout the animate being kingdom, specially primates (primate infanticide) but including microscopic rotifers, insects, fish, amphibians, birds and mammals.^[2] Infanticide can be skillful by both males and females.

Infanticide caused by sexual conflict has the full general theme of the killer (ofttimes male) becoming the new sexual partner of the victim'south parent, which would otherwise be unavailable.^[three] This represents a gain in fettle by the killer, and a loss in fitness by the parents of the offspring killed. This is a blazon of evolutionary struggle between the two sexes, in which the victim sex activity may have counter-adaptations that reduce the success of this practise.^[three] It may also occur for other reasons, such as the struggle for food between females. In this example individuals may even kill closely related offspring.

Filial infanticide occurs when a parent kills its own offspring. This sometimes involves consumption of the young themselves, which is termed filial cannibalism. The behavior is widespread in fishes, and is seen in terrestrial animals equally well. Human being infanticide has been recorded in almost every culture. A unique attribute of human infanticide is sexual practice-selective infanticide.

Background [edit]

Infanticide but came to exist seen as a significant occurrence in nature quite recently. At the time it was get-go seriously treated by Yukimaru Sugiyama,^[4] infanticide was attributed to stress causing factors like overcrowding and captivity, and was considered pathological and maladaptive. Classical ethology held that conspecifics (members of the aforementioned species) rarely killed each other.^[5] By the 1980s it had gained much greater acceptance. Possible reasons information technology was not treated as a prevalent natural phenomenon include its abhorrence to people, the popular group and species selectionist notions of the time (the thought that individuals deport for the adept of the group or species; compare with gene-centered view of evolution), and the fact that it is very difficult to notice in the field.^[6]

Infanticide involving sexual conflict [edit]

This grade of infanticide represents a struggle betwixt the sexes, where one sex exploits the other, much to the latter's disadvantage. It is usually the male who benefits from this beliefs, though in cases where males play similar roles to females in parental care the victim and perpetrator may exist reversed (run into Bateman's principle for discussion of this asymmetry).

By males [edit]

Hanuman langurs (or gray langurs) are Erstwhile World monkeys found in India. They are a social beast, living in groups that consist of a single dominant male and multiple females. The dominant male has a reproductive monopoly within the group, which causes sub-ordinate males to have a much lower fettle value in comparing.^[7] To gain the opportunity to reproduce, sub-ordinate males try to have over the dominant role within a group, usually resulting in an ambitious struggle with the existing dominant male.^[8] If successful in overthrowing the previous male, unrelated infants of the females are then killed.^[9] This infanticidal flow is limited to the window just later the group is taken over. Cannibalism, however, has not been observed in this species.

Infanticide not only reduces intraspecific contest between the incumbent's offspring and those of other males simply too increases the parental investment afforded to their own young, and allows females to become fertile faster.^[10] This is because females of this species, as well as many other mammals, do not ovulate during lactation. It and so becomes easier to sympathise how infanticide evolved. If a male kills a female person's immature, she stops lactating and is able to get pregnant once again.^[xi] Because of this, the newly dominant male is able to reproduce at a faster rate than without the deed of infanticide.^[8] As males are in a constant struggle to protect their grouping, those that express infanticidal behavior will contribute a larger portion to time to come gene pools (run into natural pick).

Like behavior is too seen in male lions, amidst other species, who also kill young cubs, thereby enabling them to impregnate the females. Dissimilar langurs, male person lions alive in small groups, which cooperate to take command of a pride from an existing group.^[ane] They volition attempt to kill whatsoever cubs that are roughly nine months old or younger, though as in other species, the female will attempt to defend her cubs viciously. Males accept, on average, only a two-twelvemonth window in which to laissez passer on their genes, and lionesses only requite birth once every 2 years, so the selective force per unit area on them to conform to this behavior is strong. In fact it is estimated that a quarter of cubs dying in the first year of life are victims of infanticide.^[1]

Male mice show keen variation in behavior over fourth dimension. Later on fertilizing a female, they become ambitious towards mouse pups for 3 weeks, killing any they come across. Later this period however, their behavior changes dramatically, and they get paternal, caring for their own offspring. This lasts for virtually ii months, but afterwards they become infanticidal one time more. It is no coincidence here that the female person gestation period is iii weeks as well, or that it takes roughly ii months for pups to get fully weaned and get out their nest. The proximate mechanism that allows for the correct timing of these periods involves cyclic rhythms (run across chronobiology), each day and night cycle affecting the mouse'due south internal neural physiology, and disturbances in the duration of these cycles results in different periods of time between behaviors.^[12] The adaptive value of this behavior switching is twofold; infanticide removes competitors for when the mouse does accept offspring, and allows the female victims to exist impregnated earlier than if they continued to care for their immature, equally mentioned in a higher place.

Gerbils, on the other mitt, no longer commit infanticide in one case they have paired with a female, merely actively kill and eat other offspring when young. The females of this species carry much like male person mice, hunting down other litters except when rearing their own.^[13]

Prospective infanticide [edit]

Prospective infanticide is a subset of sexual competition infanticide in which young born afterwards the arrival of the new male person are killed. This is less common than infanticide of existing young, just can still increment fitness in cases where the offspring could non peradventure accept been fathered by the new mate, i.e. one gestation or fertility period. This is known to occur in lions and langurs, and has besides been observed in other species such equally house wrens.^[xiv] In birds, however, the state of affairs is more circuitous, equally female eggs are fertilized ane at a time, with a 24-hour filibuster betwixt each. Males may destroy clutches laid 12 days or more after their arrival, though their investment of around 60 days of parental intendance is large, then a loftier level of parental certainty is needed.^[14]

By females [edit]

Jacana jacana females carry out infanticide.

Females are likewise known to display infanticidal behavior. This may appear unexpected, as the atmospheric condition described in a higher place do not apply. Males are not ever an unlimited resource though—in some species, males provide parental care to their offspring, and females may compete indirectly with others by killing their offspring, freeing up the limiting resources that the males stand for. This has been documented in inquiry by Stephen Emlen and Natalie Demong on wattled jacanas (Jacana jacana), a tropical wading bird.^[15] In the wattled jacana, it is exclusively the male person sex activity that broods, while females defend their territory. In this experiment Demong and Emlen institute that removing females from a territory resulted in nearby females attacking the chicks of the male person in virtually cases, evicting them from their nest. The males and then fertilized the offending females and cared for their young.^[xvi] Emlen describes how he "shot a female ane night, and ... by first light a new female was already on the turf. I saw terrible things—pecking and picking upwards and throwing down chicks until they were expressionless. Within hours she was soliciting the male, and he was mounting her the same day. The next dark I shot the other female, then came out the next forenoon and saw the whole thing once more."^[17]

Infanticide is also seen in giant water bugs.^[eighteen] Lethocerus deyrollei is a large and nocturnal predatory insect establish in still waters nearly vegetation. In this species the males accept care of masses of eggs by keeping them hydrated with water from their bodies. Without a male caring for the eggs like this, they become desiccated and will non hatch. In this species, males are a scarce resources that females must sometimes compete for. Those that cannot detect a free male often stab the eggs of a heart-searching one. Equally in the above case, males and so fertilize this female and treat her eggs. Noritaka Ichikawa has found that males only moisten their eggs during the kickoff 90 seconds or and then, after which all of the moisture on their bodies has evaporated. However, they guard the egg masses for as long as several hours at a time, when they could exist hunting casualty. They exercise not seem to foreclose further evaporation by staying guard, as males that only guarded the nest for curt periods were seen to have similar hatching rates in a controlled experiment where there were no females present. Information technology seems rather that males are more successful in fugitive infanticidal females when they are out of the water with their eggs, which might well explain the ultimate cause of this behavior.^[18]

Female person rats will eat the kits of foreign females for a source of nutrition, and to take over the nest for her own litter.^[19]

Resource competition [edit]

The Black-tailed prairie domestic dog (Cynomys ludovicianus)

Black-tailed prairie dogs are colonially-living, harem-polygynous squirrels found mainly in the U.s.a.. Their living system involves one male living with four or and so females in a territory dedicated past all individuals, and underground nesting. Black-tails just take one litter per year, and are in estrous for simply a single mean solar day effectually the beginning of leap.

A seven-year natural experiment by John Hoogland and others from Princeton University revealed that infanticide is widespread in this species, including infanticide from invading males and immigrant females, likewise as occasional cannibalism of an individual's own offspring.^[2] The surprising finding of the report was that past far the nigh common type of infanticide involved the killing of close kin's offspring. This seems illogical, as kin selection favors behaviors that promote the well-being of closely related individuals. It was postulated that this form of infanticide is more successful than trying to impale young in nearby groups, as the whole group must be bypassed in this case, while within a group only the mother need be evaded. Marauding beliefs is patently adaptive, equally infanticidal females had more and healthier young than others, and were heavier themselves as well. This behavior appears to reduce contest with other females for nutrient, and hereafter competition amongst offspring.

Similar behavior has been reported in the meerkat (Suricata suricatta), including cases of females killing their mother's, sister's, and daughter's offspring. Infanticidal raids from neighboring groups also occurred.^[20]

Other [edit]

Bottlenose dolphins have been reported to impale their young through impact injuries.^[21] Dominant male person langurs tend to kill the existing young upon taking control of a harem.^[22] There have been sightings of infanticide in the leopard population.^[23] The males of the Stegodyphus lineatus species of spider have been known to exhibit infanticide every bit a style to encourage females to mate again.

In mammals, male infanticide is near oftentimes observed in not-seasonal breeders.^[24] There is less fettle advantage for a conspecific to carry out infanticide if the interbirth period of the female parent volition not be decreased and the female volition non return to estrous. In Felidae, birthing periods tin happen anytime during the year, equally long as there is not an unweaned offspring of that female. This is a contributor to the frequency of infanticide in cannibal felids.^{[25] [24]} Some species of seasonal breeders have been observed to commit infanticide. Cases in the snub-nosed monkey, a seasonal breeding primate, accept shown that infanticide does lessen the interbirth period of the females and tin allow them to brood with the next breeding grouping.^[26] Other cases of seasonal breeding species where the infanticidal characteristic is observed has been explained as a way of preserving the female parent's resources and energy in plow increasing the reproductive success of upcoming breeding periods.^[27]

Costs and defenses [edit]

Costs of the behavior [edit]

While it may be beneficial for some species to acquit this manner, infanticide is not without risks to the perpetrator. Having already expended energy and maybe sustained serious wounds in a fight with another male person, attacks from females who vigorously defend their offspring may be telling for harem-polygynous males, with a risk of infection. It is also energetically costly to pursue a mother's young, which may try to escape.

Costs of the behavior described in prairie dogs include the risk to an individual of losing their ain young while killing another's, not to mention the fact that they are killing their ain relatives. In a species where infanticide is common, perpetrators may well be victims themselves in the time to come, such that they come out no better off; but as long as an infanticidal individual gains in reproductive output by its behavior, it will tend to become common. Farther costs of the behavior in full general may be induced by counter-strategies evolved in the other sex, as described below.

[edit]

Taking a broader view of the black-tailed prairie dog situation, infanticide tin can be seen as a cost of social living.^[two] If each female were to have her ain private nest away from others, she would exist much less likely to take her infants killed when absent. This, and other costs such as increased spread of parasites, must be fabricated up for past other benefits, such as group territory defense and increased sensation of predators.

An avian example published in Nature is acorn woodpeckers. Females nest together, possibly considering those nesting alone have their eggs constantly destroyed by rivals. Fifty-fifty then, eggs are consistently removed at start by nest partners themselves, until the unabridged group lays on the same day. They then cooperate and incubate the eggs as a group, simply by this fourth dimension a significant proportion of their eggs have been lost because of this ovicidal behavior.^[28]

Counter-strategies [edit]

Because this form of infanticide reduces the fettle of killed individuals' parents, animals take evolved a range of counter-strategies against this behavior. These may be divided into two very dissimilar classes - those that tend to prevent infanticide, and those that minimize losses.

Loss minimization [edit]

Some females abort or resorb their own immature while they are still in development afterward a new male person takes over; this is known as the Bruce effect.^[29] This may forbid their young from existence killed after nascence, saving the female parent wasted time and energy. However, this strategy also benefits the new male person. In mice this can occur by the proximate mechanism of the female smelling the odour of the new male person'due south urine.^[thirty]

Preventive adaptations [edit]

Infanticide in burying beetles may take led to male parental care.^[31] In this species males often cooperate with the female in preparing a slice of carrion, which is buried with the eggs and eaten past the larvae when they hatch. Males may too guard the site alongside the female. Information technology is credible from experiments that this behavior does not provide their young with whatsoever better nourishment, nor is information technology of whatsoever utilise in defending confronting predators. All the same, other burial bugs may try to take their nesting infinite. When this occurs, a male person-female pair is over twice as successful in nest defense force, preventing the ovicide of their offspring.

Female langurs may leave the group with their immature alongside the outgoing male, and others may develop a fake estrous and allow the male to copulate, deceiving him into thinking she is really sexually receptive.^[32] Females may also accept sexual liaisons with other males. This promiscuous behavior is adaptive, because males will non know whether it is their own offspring they are killing or not, and may exist more than reluctant or invest less endeavour in infanticide attempts.^[33] Lionesses cooperatively guard confronting scouting males, and a pair were seen to violently assail a male afterward information technology killed one of their young.^[34] Resistance to infanticide is too costly, though: for example, a female may sustain serious injuries in defending her immature. At times it is merely more advantageous to submit than to fight.^[35]

Infanticide, the destruction of offspring feature to many species, has posed so great a threat that at that place have been observable changes of beliefs in respective female mothers; more specifically, these changes exist as preventive measures. A mutual behavioral mechanism by females to reduce the take chances of infanticide of future offspring is through the process of paternity confusion or dilution. In theory, this implies that a female that mates with multiple males volition widely spread the assumption of paternity across many males, and therefore make them less likely to kill or attack offspring that could potentially behave their genes. This theory operates nether the assumption that the specific males keep a retentiveness of past mates, under a desire to perpetuate their own genes ^[36] In the Japanese macaque (macaca fuscata), female mating with multiple males, or dilution of paternity, was found to inhibit male person-to-infant aggression and infanticide 8 times less towards infants of females with which they had previously mated.^[37] Multi-male mating, or MMM, is recorded as a measure out to prevent infanticide in species where young is altricial, or heavily dependent, and where there is a high turnover rate for dominant males, which leads to infanticide of the previous dominant male person's young. Examples include, simply are non limited to; white-footed mice, hamsters, lions, langurs, baboons, and macaques.^[33] Along with mating with multiple males, the mating of females throughout the entirety of a reproductive cycle as well serves a purpose for inhibiting the hazard of infanticide. This theory assumes that males apply information on by matings to make decisions on committing infanticide, and that females afterward manipulate that knowledge. Females which are able to appear sexually active or receptive at all stages of their cycle, even during pregnancy with another male'south offspring, can confuse the males into assertive that the subsequent children are theirs.^[36] This "pseudo-estrus" theory applies to females within species that do non showroom obvious clues to each stage of their cycle, such as langurs, rhesus macaques, and gelada baboons.^[36] An alternative to paternity confusion as a method of infanticide prevention is paternity concentration. This is the beliefs of females to concentrate paternity to one specific ascendant male as a means of protection from infanticide at the hands of less-dominant males.^[33] This specially applies to species in which a male has a very long tenure as the dominant male, and faces niggling instability in this hierarchy. Females choose these dominant males as the all-time available form of protection, and therefore mate exclusively with this male. This is especially common within pocket-size rodents.^[33] An additional behavioral strategy to forestall infanticide by males may be ambitious protection of the nest along with female presence. This strategy is normally used in species such as European rabbits.^{[38] [39]} Ambitious protection of the nest in an effort to reduce infanticide is observed with the Blackness Stone Skink. Egernia saxatilis live in small families and adults defend their territories against conspecifics. The small "nuclear families" alive in the same permanent shelter and the parents protect their infants from infanticidal conspecifics in this way. Adults attack unrelated juveniles only not their ain offspring. The presence of a parent significantly reduces the charge per unit of infanticide because conspecific adults ignore juveniles when a parent is present, likely because another developed is more threatening to the aggressive lizard. Therefore, a juvenile living inside its parents' own territory will experience far less attacks from conspecific adults.^{[twoscore] [41]}

Infanticide by parents and caregivers [edit]

Damselfish may eat their own offspring.^[42]

Filial infanticide occurs when a parent kills its own offspring. Both male and female parents have been observed to do this, as well as sterile worker castes in some eusocial animals. Filial infanticide is also observed as a grade of brood reduction in some birds species, such as the white stork.^[43] This may be due to a lack of siblicide in this species.^[44]

Maternal [edit]

Maternal infanticide occurs when newborn offspring are killed past their female parent. This is sometimes seen in pigs,^[45] a behavior known equally savaging, which affects up to 5% of gilts. Similar beliefs has been observed in diverse animals such as rabbits,^[46] hamsters^[47], humans and burial beetles.^[48]

Paternal [edit]

Paternal infanticide—where fathers swallow their own offspring—may besides occur. When young bass hatch from the spawn, the male parent guards the expanse, circling around them and keeping them together, as well as providing protection from would-be predators. After a few days, most of the fish will swim away. At this point the male person's beliefs changes: instead of defending the stragglers, he treats them as whatever other small prey, and eats them.^[49]

Worker degree killing immature [edit]

Beloved bees may become infected with a bacterial illness called foul brood, which attacks the developing bee larva while even so living in the cell. Some hives nevertheless accept evolved a behavioral adaptation that resists this disease: the worker bees selectively kill the infected individuals by removing them from their cells and tossing them out of the hive, preventing information technology from spreading. The genetics of this beliefs are quite circuitous. Experiments by Rothenbuhler showed that the 'hygienic' behavior of the queen was lost past crossing with a non-hygienic drone. This means that the trait must be recessive, just existence expressed when both alleles contain the cistron for hygienic beliefs. Furthermore, the behavior is dependent on two separate loci. A backcross produced a mixed upshot. The hives of some offspring were hygienic, while others were not. At that place was also a third type of hive where workers removed the wax cap of the infected cells, but did nothing more than. What was non apparent was the presence of a 4th group who threw diseased larvae out of the hive, just did not have the uncapping gene. This was suspected past Rothenbuhler however, who manually removed the caps, and found some hives proceeded to clear out infected cells.^{[l] [51]}

Humans and infanticide [edit]

Family construction is the most of import run a risk gene in kid abuse and infanticide. Children who live with both their natural (biological) parents are at low risk for abuse. The risk increases profoundly when children live with step-parents or with a single parent. Children living without either parent (foster children) are 10 times more than likely to exist abused than children who live with both biological parents.^{[ citation needed ]}

Children who live with a unmarried parent that has a live-in partner are at the highest chance: they are 20 times more likely to be victims of child abuse than children living with both biological parents.^[52]

Infanticide is a subject that some humans may notice discomforting. Cornell University ethologist Glenn Hausfater states that "infanticide has not received much study because it's a repulsive subject [...] Many people regard it every bit reprehensible to even think nigh it." Research into infanticide in animals is in part motivated past the desire to sympathise human behaviors, such equally child abuse. Hausfater explains that researchers are "trying to see if at that place's whatever connection between animal infanticide and child abuse, neglect and killing by humans [...] We just don't know nonetheless what the connections are."^[53]

Infanticide has been, and all the same is, adept by some human cultures, groups, or individuals.^{[ citation needed ]} In many past societies, certain forms of infanticide were considered permissible, whereas in well-nigh modernistic societies the exercise is considered immoral and criminal. It nonetheless takes identify in the Western world unremarkably because of the parent's mental affliction or violent behavior, in addition to some poor countries equally a form of population command — sometimes with tacit societal acceptance. Female infanticide, a course of sex-selective infanticide, is more common than the killing of male person offspring, especially in cultures where male children are more desirable.

Come across also [edit]

• Homo infanticide
• Infanticide in carnivores
• Infanticide in primates
• Infanticide in rodents
• Parent–offspring disharmonize
• Parricide
• Paternal care
• Runt
• Sexual cannibalism
• Sexual selection
• Siblicide

Farther reading [edit]

• Alcock, J. (1998). Animal Behavior: An Evolutionary Approach (sixth ed.). Sinauer Associates, Inc. Sunderland, Massachusetts. ISBN978-0-87893-009-eight.
• Parmigiani, South.; vom Saal, F.S. (1994). Infanticide and Parental Intendance. Harwood: London. p. 493. ISBN978-3-7186-5505-2.
• van Schaik, C.P.; Janson, C.H. (2000). Infanticide By Males And Its Implications. Cambridge University Press. p. 569. ISBN978-0-521-77295-two.

References [edit]

1. ^ ^{a b c} Pusey, A.East.; Packer, C. (1994). "Infanticide in lions". In Parmigiani, Southward.; vom Saal, F.S. (eds.). Infanticide and Parental Care. Harwood Academic Printing, Chur, Switzerland. ISBN9783718655052.
2. ^ ^{a b c} Hoogland, J. Fifty. (1985). "Infanticide in prairie dogs: Lactating females kill offspring of shut kin". Scientific discipline. 230 (4729): 1037–1040. Bibcode:1985Sci...230.1037H. doi:x.1126/science.230.4729.1037. PMID 17814930. S2CID 23653101.
3. ^ ^{a b} Palombit, Ryne A. (2015-06-01). "Infanticide as Sexual Conflict: Coevolution of Male person Strategies and Female person Counterstrategies". Cold Spring Harbor Perspectives in Biology. seven (6): a017640. doi:10.1101/cshperspect.a017640. ISSN 1943-0264. PMC4448612. PMID 25986557.
4. ^ Sugiyama, Y. (1965). "On the social change of Hanuman langurs (Presbytis entellus) in their natural conditions". Primates. 6 (3–iv): 381–417. doi:10.1007/BF01730356. S2CID 26758190.
5. ^ Lorenz, K. (1966). On Aggression. New York: Harcourt, Brace and Worl.
6. ^ Hausfater, 1000.; Southward.B. Hrdy (1984). Infanticide: Comparative and Evolutionary Perspectives. New York, Aldine. ISBN978-0-202-02022-8.
7. ^ "Mating conflict in primates: infanticide, sexual harassment and female person sexuality".
8. ^ ^{a b} Lukas, Dieter; Huchard, Elise (2014). "The evolution of infanticide by males in mammalian societies" (PDF). Science. 346 (6211): 841–4. Bibcode:2014Sci...346..841L. doi:10.1126/science.1257226. PMID 25395534. S2CID 206559886.
9. ^ Hrdy, D. B. (1977). "Infanticide as a primate reproductive strategy". American Scientist. 65 (1): 40–49. Bibcode:1977AmSci..65...40B. PMID 402873.
10. ^ Hausfater, Glenn (1984-08-01). "Infanticide: Comparative and Evolutionary Perspectives". Current Anthropology. 25 (iv): 500–502. doi:ten.1086/203169. ISSN 0011-3204. S2CID 84753908.
11. ^ Hausfater, Glenn (1984-08-01). "Infanticide: Comparative and Evolutionary Perspectives". Current Anthropology. 25 (4): 500–502. doi:x.1086/203169. ISSN 0011-3204. S2CID 84753908.
12. ^ Perrigo, Chiliad.; Bryant, W. C.; Vomsaal, F (1990). "A unique neural timing system prevents male mice from harming their own offspring". Animal Behaviour. 39 (3): 535–539. doi:x.1016/S0003-3472(05)80419-i. S2CID 53200704.
13. ^ Hausfater, M. (1984). "Infanticide: Comparative and evolutionary perspectives". Electric current Anthropology. 25 (iv): 500–502. doi:10.1086/203169. JSTOR 2742911. S2CID 84753908.
14. ^ ^{a b} Freed, L. A. (1987). "Prospective infanticide and protection of genetic paternity in tropical firm wrens". The American Naturalist. 130 (6): 948–954. doi:10.1086/284758. S2CID 84236418.
15. ^ Emlen, S. T.; Demong, N. J.; Emlen, D. J. (1989). "Experimental induction of infanticide in female wattled jacanas" (PDF). Auk. 106 (ane): 1–7. doi:10.2307/4087750. JSTOR 4087750.
16. ^ For footage of this, see Attenborough, D. (1990) The Trials of Life, Episode 12, or Evolution, Episode three "Why Sexual activity?".
17. ^ Zimmer, Carl (1996-09-01). "First, impale the babies". Discover . Retrieved 2008-01-xix .
18. ^ ^{a b} Ichikawa, Northward. (1995). "Male counterstrategy against infanticide of the female giant water bug Lethocerus deyrollei (Hemiptera: Belostomatidae)". Journal of Insect Behavior. eight (2): 181–186. doi:10.1007/BF01988903. S2CID 41306483.
19. ^ Infanticide in Kingdom of norway rats. ratbehavior.org
20. ^ Clutton-Brock, T. H.; P. N. M., B.; Smith, R.; McIlrath, Thou. Yard.; Kansky, R.; Gaynor, D.; O'Riain, M. J.; Skinner, J. D. (1998). "Infanticide and expulsion of females in a cooperative mammal". Proceedings: Biological Sciences. 265 (1412): 2291–2295. doi:10.1098/rspb.1998.0573. JSTOR 51272. PMC1689533. PMID 9881475.
21. ^ Milius, Due south. (July 18, 1998). "Infanticide reported in dolphins". Science News. Vol. 154, no. 3. p. 36. doi:10.2307/4010610. JSTOR 4010610. Retrieved 2007-05-22 .
22. ^ "The evolution of infanticidal mechanisms in male langurs" (PDF) . Retrieved 2007-05-22 . ^{[ permanent dead link ]}
23. ^ Fildes, Jonathan (2007-05-29). "Cheating cheetahs defenseless past Deoxyribonucleic acid". BBC News . Retrieved 2007-05-30 .
24. ^ ^{a b} Lukas, Dieter; Huchard, Elise (2014-11-14). "The evolution of infanticide by males in mammalian societies" (PDF). Science. 346 (6211): 841–844. Bibcode:2014Sci...346..841L. doi:10.1126/science.1257226. ISSN 0036-8075. PMID 25395534. S2CID 206559886.
25. ^ Balme, Guy A.; Hunter, Luke T.B. (2013-10-01). "Why leopards commit infanticide". Animal Behaviour. 86 (four): 791–799. doi:x.1016/j.anbehav.2013.07.019. ISSN 0003-3472. S2CID 53266285.
26. ^ Yao, Hui; Yu, Huiliang; Yang, Banghe; Yang, Wangji; Xu, Haiqing; Grueter, Cyril C.; Li, Ming; Xiang, Zuofu (2016-02-02). "Male Infanticide in the Golden Snub-Nosed Monkey (Rhinopithecus roxellana), a Seasonally Breeding Primate". International Journal of Primatology. 37 (two): 175–184. doi:x.1007/s10764-016-9892-ii. ISSN 0164-0291. S2CID 14544830.
27. ^ Hrdy, Sarah; Hausfater, G (1984-01-01). "Comparative and evolutionary perspectives on infanticide: An introduction and overview". Comparative and Evolutionary Perspectives.
28. ^ Mumme, R. 50.; Koenig, W. D.; Pitelka, F. A. (1983). "Reproductive contest in the communal acorn woodpecker: Sisters destroy each other's eggs". Nature. 306 (5943): 583–584. Bibcode:1983Natur.306..583M. doi:10.1038/306583a0. S2CID 19299353.
29. ^ Bruce, H. Thousand. (1959). "An exteroceptive block to pregnancy in the mouse". Nature. 184 (4680): 105. Bibcode:1959Natur.184..105B. doi:ten.1038/184105a0. PMID 13805128. S2CID 4200823.
30. ^ Labov, J. B. (1981). "Pregnancy blocking in rodents: Adaptive advantages for females". American Naturalist. 118 (3): 361–371. doi:x.1086/283828. JSTOR 2460637. S2CID 85020158.
31. ^ Scott, M. P. (1990). "Breed guarding and the development of male parental care in burying beetles". Behavioral Environmental and Sociobiology. 26 (i): 31–xl. doi:10.1007/BF00174022. JSTOR 4600371. S2CID 23748510.
32. ^ Hrdy, South.B. (1977). The Langurs of Abu . Harvard University Press, Cambridge, MA. ISBN978-0674510586.
33. ^ ^{a b c d} Agrell, J.; Wolff, J.; Ylönen, H.; Ylonen, Hannu (1998). "Counter-strategies to infanticide in mammals: Costs and consequences". Oikos. 83 (three): 507–517. doi:ten.2307/3546678. JSTOR 3546678.
34. ^ Packer, C.; Pusey, A. (1983). "Adaptations of female person lions to infanticide by incoming males". The American Naturalist. 121 (five): 716–728. doi:x.1086/284097. S2CID 84927815.
35. ^ Yamamura, N.; Hasegawa, T.; Ito, Y. (1990). "Why mothers do not resist infanticide: A toll-benefit genetic model" (PDF). Development. 44 (v): 1346–1357. doi:10.2307/2409294. JSTOR 2409294. PMID 28563893.
36. ^ ^{a b c} Hrdy, S. B. (1979). "Infanticide amid animals: A review, nomenclature, and test of the implications for the reproductive strategies of females". Ethology and Sociobiology. 1: 13–eighteen. doi:10.1016/0162-3095(79)90004-9.
37. ^ Soltis, J.; Thomsen, R.; Matsubayashi, Yard.; Takenaka, O. (2000). "Infanticide by resident males and female counter-strategies in wild Japanese macaques ( Macaca fuscata )". Behavioral Ecology and Sociobiology. 48 (3): 195. doi:ten.1007/s002650000224. S2CID 22485349.
38. ^ Rödel, H.1000; Starkloff, A (2008). "Infanticide and maternal offspring defense in european rabbits nether natural breeding conditions". Ethology. 114 (ane): 22–31. doi:ten.1111/j.1439-0310.2007.01447.ten.
39. ^ Yöken, H.; Haapakoski, A. (2017). "How practise infanticidal male banking concern voles (myodes glarelus) observe the next with pups?". Ethology. 123 (2): 105–112. doi:x.1111/eth.12579.
40. ^ O'Connor D, Smooth R (2004) Parental care protects against infanticide in the lizard Egernia saxatilis(Scincidae). Animal Behaviour 68, 1361–1369.
41. ^ O'Connor, D. and Shine, R. (2003), Lizards in 'nuclear families': a novel reptilian social arrangement in Egernia saxatilis (Scincidae). Molecular Ecology, 12: 743-752. https://doi.org/10.1046/j.1365-294X.2003.01777.10
42. ^ Payne, A. G.; Smith, C.; Campbell, A. C. (2002). "Filial cannibalism improves survival and development of Beaugregory damselfish embryos". Proceedings: Biological Sciences. 269 (1505): 2095–2102. doi:x.1098/rspb.2002.2144. PMC1691142. PMID 12396483.
43. ^ Tortosa, Francisco Southward.; Redondo, Tomas (1992). "Motives for Parental Infanticide in White Storks Ciconia ciconia". Ornis Scandinavica (Scandinavian Journal of Ornithology). 23 (2): 185–189. doi:10.2307/3676447. JSTOR 3676447.
44. ^ Zieliński, Piotr (December 2002). "Brood Reduction and Parental Infanticide — are the White StorkCiconia ciconiaand the Black StorkC. nigraexceptional?". Acta Ornithologica. 37 (2): 113–119. doi:10.3161/068.037.0207. ISSN 0001-6454.
45. ^ N Carolina Pork Conference Archived 2007-08-twenty at the Wayback Machine notes. 2002. North Carolina State University.
46. ^ Boyd, I. L. (1985). "Investment in growth by pregnant wild rabbits in relation to litter size and sex of the offspring". The Journal of Animal Ecology. 54 (1): 137–147. doi:10.2307/4626. JSTOR 4626.
47. ^ "What Tin can You Do to Keep Your Hamster From Eating Its Own Babies?". The Spruce Pets . Retrieved 2022-06-15 .
48. ^ Trumbo, S. (1994). "Interspecific competition, breed parasitism, and the evolution of biparental cooperation in Burying beetles". Oikos. 69 (2): 241–249. doi:10.2307/3546144. JSTOR 3546144.
49. ^ Elgar, M.A.; Crespi, B.J., eds. (1992). Cannibalism: Environmental and Evolution of Cannibalism amidst Diverse Taxa. Oxford University Printing, New York. ISBN978-0-19-854650-4.
50. ^ Dawkins, R. (1976). The Selfish Factor. Oxford University Press. ISBN978-0-nineteen-286092-seven.
51. ^ Rothenbuhler, W. C. (1964). "Behavior genetics of nest cleaning in love bees. IV. Responses of F₁ and backcross generations to disease killed breed". American Zoologist. 4 (two): 111–123. doi:10.1093/icb/4.two.111. PMID 14172721.
52. ^ Sedlak, A.J., Mettenburg, J., Basena, One thousand., Petta, I., McPherson, M., Greene, A., and Li, S. (2010). Fourth National Incidence Report of Child Corruption and Neglect (NIS–four): Report to Congress, Executive Summary. Washington, DC: U.South. Department of Health and Human Services, Assistants for Children and Families.
53. ^ Bayard Webster (1982-08-17). "Infanticide: Creature beliefs scrutinized for clues to humans". The New York Times . Retrieved 2008-01-18 .

Source: https://en.wikipedia.org/wiki/Infanticide_(zoology)

Posted by: browngribetwouter.blogspot.com

Share this post