He theorized a heritable component in altruism and developed Genetic Similarity Theory, which is an extension of W. D. Hamilton's theory of kin selection.

Judith Anderson said his work was based on statistically flawed evidence, John Archer and others said that Rushton failed to understand and misapplied the theory of kin selection, Judith Economos said he was speculative and failed to define the concept of altruistic behavior in a way that it can become manifest and failed to show any plausible mechanism by which members of a species can detect the " altruism gene " in other members of the species, and Steven Gangestad criticized the theory for not being compelling in terms of its attractiveness as an explanatory model, C. R.

The unit of selection can be the individual or it can be another level within the hierarchy of biological organisation, such as genes, cells, and kin groups.

Ecological selection covers any mechanism of selection as a result of the environment ( including relatives, e. g. kin selection, competition, and infanticide ), while " sexual selection " refers specifically to competition for mates.

This selection can be seen as a compromise between factions, Borgia and della Rovere, picking a frail cardinal with long experience in the Curia over the kin of either Sixtus IV or Alexander VI.

Studies of black-tailed prairie dogs suggest that alarm-calling is a form of kin selection, as a prairie dog ’ s call alerts both offspring and nondescended kin, such as cousins, nephews and nieces.

But Gould did not rule out sociobiological explanations for many aspects of animal behavior, writing: " Sociobiologists have broadened their range of selective stories by invoking concepts of inclusive fitness and kin selection to solve ( successfully I think ) the vexatious problem of altruism — previously the greatest stumbling block to a Darwinian theory of social behavior ...

Mechanistically, the impact of Snowball Earth ( in particular the later glaciations ) on complex life is likely to have occurred through the process of kin selection.

) Because relatives share genes, genes causing altruism ( such as organ scale differentiation ) can spread if it occurs between relatives, see kin selection.

Hamilton's insight was to show how kin selection could explain altruism and spite.

Thus, it seems much more probable that this example is a case of kin selection than reciprocal altruism.

In particular, phenomena such as kin selection and eusociality, where organisms act altruistically, against their individual interests ( in the sense of health, safety or personal reproduction ) to help related organisms reproduce, can be explained as gene sets " helping " copies of themselves ( or sequences with the same phenotypic effect ) in other bodies to replicate.

This is believed to be significant for the development of eusociality, as it increases the significance of kin selection, but it is debated.

This hypothesis is an extension of the theory of kin selection.

Charles Darwin was the first to discuss the concept of kin " group " selection.

These passages and others by Darwin about " kin selection " are highlighted and justly celebrated in D. J.

The earliest mathematically formal treatments of kin selection were by R. A. Fisher in 1930 and J.

The term " kin selection " may first have been coined by John Maynard Smith in 1964:

These processes I will call kin selection and group selection respectively.

… By kin selection I mean the evolution of characteristics which favour the survival of close relatives of the affected individual, by processes which do not require any discontinuities in the population breeding structure.

According to this fundamental principle of kin selection theory, the enhanced fitness of relatives can at times more than compensate for the fitness loss incurred by the individuals displaying the behaviour.

Hamilton's later clarifications often go unnoticed, and because of the persistence of the long standing assumption that kin selection theory necessarily predicts that social cooperation requires innate powers of kin recognition, some theorists have tried to clarify the position in recent work:

The assumption that innate power of kin recognition must be present, and that cue-based mediation of social cooperation based on limited dispersal and shared developmental context are not sufficient, has obscured significant progress made in applying kin selection and inclusive fitness theory to a wide variety of species, including humans, on the basis of cue-based mediation of social bonding and social behaviours.

Evolutionary psychologists, following Darwinian anthropologists ' interpretation of kin selection theory initially attempted to explain human altruistic behavior through kin selection by stating that " behaviors that help a genetic relative are favored by natural selection.

The theory of kin selection has had a profound impact on interpretations of genetic evolution of eusociality but it has been recently criticized in a paper in Nature by Martin Nowak, Corina Tarnita, and E. O. Wilson.

In trying to resolve the problems of dubious inferences about kinship " systems ", George P. Murdock ( 1949, Social Structure ) compiled kinship data to test a theory about universals in human kinship in the way that terminologies were influenced by the behavioral similarities or social differences among pairs of kin, proceeding on the view that the psychological ordering of kinship systems radiates out from ego and the nuclear family to different forms of extended family.

Early derivations of Kin selection theory and the related field of Sociobiology, encouraged some biologists such as Darwinian anthropologists and evolutionary psychologists to approach human kinship with the assumption that kin selection theory predicts that kinship relations in humans are indeed expected to depend on genetic relatedness, which they readily connected with the genealogy approach of early anthropologists such as Morgan ( see above sections ).

Holland in a 2004 thesis argued that biologists themselves have not sufficiently recognised that kin selection theory does not in fact require that genetic relatedness per se is the condition that mediates social bonding and social cooperation in any species.

In ancestral environments, social cooperation mediated through ties of familiarity and attachments would typically have increased the inclusive fitness of genes ( the key criterion in kin selection theory ) without any form of detection of actual genetic relationships.

Bowlby himself emphasized the compatibility of his own work with kin selection theory.

The fire ant Solenopsis invicta also presents a paradox for kin selection theory.

* inclusive fitness, in evolutionary theory, how many kin are supported including non-descendants

Hamilton did much more that merely develop a kin component to explain the spread of a gene shared through identical descent, i. e. kin selection theory ( although that in itself is rich in its implications, since chromosome architectures do indeed differ among kin groups ).

He developed the broad and encompassing inclusive fitness theory that can explain a gene's spread in any number of ways, e. g., through purely Selfish behavior ( actor benefits, the recipient does not ), through reciprocity or mutualism ( actor and recipient benefit, even if benefits are selfish in gain ), through delayed reciprocity ( a uniquely dominant human behavior ), as well as altruistic social behavior among kin ( benefits to actor and recipient are realized to be similar as they share the same gene by common descent that is being replicated ).

In collaboration with her husband and colleague David C. Queller, she has measured genetic relatedness within colonies of many wasp species, and showed that kin selection theory predicts the existence and outcome of within-family conflicts of interest.

As such, this is a special case of a more general model, called inclusive fitness ( in that inclusive fitness refers simply to gene copies in other individuals without requiring that they be kin ).

A thought experiment on the kin recognition / discrimination distinction is the hypothetical ' green beard ', where a gene for social behaviour is imagined to also cause a distinctive phenotype that can be recognised by other carriers of the gene.

For example, using Hamilton's broad based inclusive fitness model ( Hamilton 1964 a, b ), Robert Trivers ' in Social Evolution ( Trivers 1985 ) has outlined how a selfish gene can maximize its inclusive fitness, spreading copies of itself via interactions that lead solely to selfishness, or to mutualism with unrelated individuals, or to delayed reciprocity, a highly specialized reciprocity that can involve both kin and non-kin that is subject to cheating and remembering cheaters, or to facultative altruism and obligate altruism with kin.

Phratries contained smaller kin groups called gene ; these appear to have arisen later than phratries, and it appears that not all members of phratries belonged to a genos ; membership in these smaller groups may have been limited to elites.

This process produces adaptations for the benefit of genes that promote the reproductive success of the organism, or of other organisms containing the same gene ( kin altruism and green-beard effects ), or even only its own propagation in detriment to the other genes of the genome ( intragenomic conflict ).

They may have been annihilated ( like the Pinaleño-Nednhi ) or had joined more mighty local groups ( the remnant of the Carrizaleños-Nedhni camped together with their northern kin, the Janero-Nednhi ).

Such people, who may be real but impersonated people or fictitious characters played by the con artist, could include, for example, the wife or son of a deposed African or Indonesian leader or dictator who has amassed a stolen fortune, or a bank employee who knows of a terminally ill wealthy person with no relatives or a wealthy foreigner who deposited money in the bank just before dying in a plane crash ( leaving no will or known next of kin ), a US soldier who has stumbled upon a hidden cache of gold in Iraq, a business being audited by the government, a disgruntled worker or corrupt government official who has embezzled funds, a refugee, and similar characters.

It may also be the case in competition between members of the same species or subgroup, if the average reward ( e. g. status, access to resources, protection of self or kin ) outweighs average costs ( e. g. injury, exclusion from the group, death ).

Note also that kin recognition may be selected for inbreeding avoidance, and little evidence indicates that ' innate ' kin recognition plays a role in mediating altruism.

Here, social partners are typically genealogically close kin, and so altruism may be able to flourish even in the absence of kin recognition and kin discrimination faculties — spatial proximity and circumstantial cues serve as a rudimentary form of discrimination.

By providing close kin with inherited wealth, an individual may improve his or her kin ’ s reproductive opportunities and thus increase his or her own inclusive fitness even after death.

Numerous other studies pertaining to kin selection exist, suggesting how inclusive fitness may work amongst peoples from the Ye ’ kwana of southern Venezuela to the Gypsies of Hungary to even the doomed Donner Party of the United States.

Coenwulf's kin may have been connected to the royal family of the Hwicce, a subkingdom of Mercia around the lower river Severn.

It may represent a significant change from an earlier time when a man's kin were expected to support him with oaths.

There may be religious objections to family's next of kin having their loved ones dissolved, flushed to a sewer treatment plant, and applied to a farm field in the form of sludge.

Alternatively, airborne embers ( or their smaller kin, sparks ) may ignite dead material in overhanging branches.

The close kin or kiri mate (" dead skin ") may not speak.

Working single mothers may also rely on the help from fictive kin, who provide for the children while the mother is at her job.

He said that the DLP and ALP differed in a number of ways, however " We both came from the same lineage and however some members on both sides may dislike it, we are kin, of sorts.

Allosucking does not seem to be a case of mistaken identity or milk theft and may be a sign of kin altruism.

On one hand, Eärnil's selection may have averted another kin strife.

As a result, the lover has no legal control over the children, who may be taken away from him by the kin of the pater when they choose.

Whilst someone is alive they may nominate any person close to them to be their next of kin.

On his attestation papers, he claimed to be born in Montreal on Sept 18, 1888, and listed no next of kin, however when asked about his marital status, it appears some confusion may have taken place as the word ' yes ' was written, and then crossed out, then the word ' no ' was written, and then crossed out ultimately not clearly answering the question, leaving his marital status unclear to the military at the time of enlistment.

It may be divided into potential energy ( U < sub > pot </ sub >) and kinetic energy ( U < sub > kin </ sub >) components: