Who identified inclusive fitness theory?
50797822#14
A common source of confusion around inclusive fitness theory is that Hamilton's early analysis included some inaccuracies, that, "although corrected by him in later publications", are often not fully understood by other researchers who attempt to apply inclusive fitness to understanding organisms' behaviour. For example, Hamilton had initially suggested that the statistical correlation in his formulation could be understood by a correlation coefficient of genetic relatedness, but quickly accepted George Price's correction that a general regression coefficient was the more relevant metric, and together they published corrections in 1970. A related confusion is the connection between inclusive fitness and multi-level selection, which are often incorrectly assumed to be mutually exclusive theories. The regression coefficient helps to clarify this connection:
Inclusive fitness in humans
678078#2
Hamilton showed mathematically that, because other members of a population may share one's genes, a gene can also increase its evolutionary success by indirectly promoting the reproduction and survival of other individuals who also carry that gene. This is variously called "kin theory", "kin selection theory" or "inclusive fitness theory". The most obvious category of such individuals is close genetic relatives, and where these are concerned, the application of inclusive fitness theory is often more straightforwardly treated via the narrower kin selection theory.
Inclusive fitness
426305#9
Inclusive fitness theory, first proposed by W. D. Hamilton in the early 1960s, gives a selection criterion for evolution of social traits when social behavior is costly to an individual organism's survival and reproduction. This behavior could emerge under conditions such that the statistical likelihood that benefits accrue to the survival and reproduction of other organisms whom also carry the social trait. Inclusive fitness theory is a general treatment of the statistical probabilities of social traits accruing to any other organisms likely to propagate a copy of the same social trait. Kin selection theory treats the narrower but simpler case of the benefits to close genetic relatives (or what biologists call 'kin') who may also carry and propagate the trait. A significant group of biologists support inclusive fitness as the explanation for social behavior in a wide range of species, as supported by experimental data. An article was published in "Nature" with over a hundred coauthors.
Group selection
50797822#7
Inclusive fitness theory, first proposed by Bill Hamilton in the early 1960s, proposes a selective criterion for the potential evolution of social traits in organisms, where social behavior that is costly to an individual organism's survival and reproduction could nevertheless emerge under certain conditions. The key condition relates to the statistical likelihood that significant benefits of a social trait or behavior accrue to (the survival and reproduction of) other organisms whom also carry the social trait. Inclusive fitness theory is a general treatment of the statistical probabilities of social traits accruing to any other organisms likely to propagate a copy of the same social trait. Kin selection theory treats the narrower but more straightforward case of the benefits accruing to close genetic relatives (or what biologists call 'kin') who may also carry and propagate the trait. Under conditions where the social trait sufficiently correlates (or more properly, "regresses") with other likely bearers, a net overall increase in reproduction of the social trait in future generations can result.
Inclusive fitness in humans
31880880#10
Inclusive fitness theory, proposed by William D. Hamilton, emphasized a "gene's-eye" view of evolution. Hamilton noted that what evolution ultimately selects are genes, not groups or species. From this perspective, individuals can increase the replication of their genes into the next generation not only directly via reproduction, by also indirectly helping close relatives with whom they share genes survive and reproduce. General evolutionary theory, in its modern form, "is" essentially inclusive fitness theory.
Theoretical foundations of evolutionary psychology
678078#41
In a 2010 paper by Martin Nowak, Corina Tarnita and E. O. Wilson, it was suggested that standard natural selection theory is superior to inclusive fitness theory, stating that the interactions between cost and benefit cannot be explained only in terms of relatedness. This, Nowak said, makes Hamilton's rule at worst superfluous and at best ad hoc. Gardner in turn was critical of the paper, describing it as "a really terrible article", and along with other co-authors has written a reply, submitted to "Nature".
Inclusive fitness
678078#0
In evolutionary biology, inclusive fitness is one of two metrics of evolutionary success as defined by W. D. Hamilton in 1964:An individual's own child, who carries one half of the individual's genes, is defined as one offspring equivalent. A sibling's child, who will carry one-quarter of the individual's genes, is 1/2 offspring equivalent. Similarly, a cousin's child, who has 1/16 of the individual's genes, is 1/8 offspring equivalent.
Inclusive fitness
50797822#6
Whilst the above understanding of inclusive fitness theory as necessarily making predictions about how human kinship and altruism is mediated is common amongst evolutionary psychologists, other biologists and anthropologists have argued that it is at best a limited (and at worst a mistaken) understanding of inclusive fitness theory. These scientists argue that the theory is better understood as simply describing an "evolutionary" criterion for the emergence of altruistic behaviour, which is explicitly statistical in character, not as predictive of "proximate" or "mediating" mechanisms of altruistic behaviour, which may not necessarily be determined by genetic relatedness (or blood ties) "per se". These alternative non-deterministic and non-reductionist understandings of inclusive fitness theory and human behavior have been argued to be compatible with anthropologists' decades of data on human kinship, and compatible with anthropologists' perspectives on human kinship. This position (e.g. nurture kinship) has been largely accepted by social anthropologists, whilst the former position (still held by evolutionary psychologists, see above) remains rejected by social anthropologists.
Inclusive fitness in humans
32751715#7
Darwinian anthropology was critiqued by Symonds for its agnosticism as to the psychological mechanisms governing how social behavior is actually expressed in the human species, and its reliance on interpreting inclusive fitness theory to simply imply that "humans have evolved to be inclusive fitness maximizers". This section will review some of the relevant background discussion in inclusive fitness theory to clarify why this position was considered untenable.
Darwinian anthropology
265570#45
Early developments of biological inclusive fitness theory and the derivative field of Sociobiology, encouraged some sociobiologists and evolutionary psychologists to approach human kinship with the assumption that inclusive fitness 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). However, this is the position that Schneider, Sahlins and other anthropologists explicitly reject.
Kinship
43868891#1
The aim of the book is to show that ""properly interpreted, cultural anthropology approaches (and ethnographic data) and biological approaches are perfectly compatible regarding processes of social bonding in humans."" Holland's position is based on demonstrating that the dominant biological theory of social behavior (inclusive fitness theory) is typically misunderstood to predict that genetic ties are necessary for the "expression" of social behaviors, whereas in fact the theory only implicates genetic associations as necessary for the "evolution" of social behaviors. Whilst rigorous evolutionary biologists have long understood the distinction between these levels of analysis (see Tinbergen's four questions), past attempts to apply inclusive fitness theory to humans have often overlooked the distinction between "evolution" and "expression".
Social Bonding and Nurture Kinship