Experimental evidence for kin-biased helping in a cooperatively breeding vertebrate

The widespread belief that kin selection is necessary for the evolution of cooperative breeding in vertebrates has recently been questioned. These doubts have primarily arisen because of the paucity of unequivocal evidence for kin preferences in cooperative behaviour. Using the cooperative breeding system of long-tailed tits (Aegithalos caudatus) in which kin and non-kin breed within each social unit and helpers are failed breeders, we investigated whether helpers preferentially direct their care towards kin following breeding failure. First, using observational data, we show that not all failed breeders actually become helpers, but that those that do help usually do so at the nest of a close relative. Second, we confirm the importance of kinship for helping in this species by conducting a choice experiment. We show that potential helpers do not become helpers in the absence of close kin and, when given a choice between helping equidistant broods belonging to kin and non-kin within the same social unit, virtually all helped at the nest of kin. This study provides strong evidence that kinship plays an essential role in the maintenance of cooperative breeding in this species

CHAPTER 8: DWIGHT READ: TOWARDS A NEW PARADIGM: FOLLOWED BY A DISCUSSION BETWEEN THE AUTHOR AND DWIGHT READ

Here I report on Dwight Read’s theory for a paradigm change in kinship anthropology which entails kinship terminologies being interpreted as symbolic computational systems based on kin-term products. I also report on how Read argues that different conceptualizations of sibling, either sibling resulting by descent from parent, or sibling viewed in terms of shared parentage, two cultural conceptions that are rendered – here exemplifying the masculine side – by the kin-term products, S o F = B [son of father = brother] or F o B = F [father of brother = father), lead to respectively building up a descriptive or a classificatory terminology. The chapter also deals with how Dwight Read accounts for the relationship between genealogical tracing and the working out of kin terms using kin-term products and how the logic of kin-term products is consistent with the extension of kin terms to kin-type categories beyond the primary ones.The paper also reports on a discussion between Dwight Read and the author, initiated by questions and observations from the latter, regarding different aspects of Read’s reasoning. Not exhaustively, to be mentioned here is the way kin relationships are concretely worked out using kin-term products, the model of the family space and the nuclear family, group marriage,  how the conceptualization of sibling in terms of shared parentage expressed through the kin-term product F o B = F [father o brother = father] relates to ethnographic data, the nature of the logic of kinship terminologies, the status of the structural equation S o F = B [son o father = brother] when used within the context of a classificatory terminology, the axiomatic nature of a number of kin-term products pertaining to specific kin terminologies, the equations pertaining to classificatory kinship terminologies that are  likely to algebraically reduce chains of kin-terms products, mapped from corresponding kin type strings, like “son of son of father of father of father” (S o S o F o F o F) is mapped from the collateral genealogical relations, father’s father’s father’s son’s son (fffss or fffbss) to an irreducible kin term, here father, which is the one native speakers use for the said genealogical connection.The discussion also addresses, taking the example of ancient Chinese dialects, the question of what should be the structural prerequisites for a transition from classificatory (Dravidian) terminologies into bifurcate collateral and descriptive terminologies, a transition that is often posited by a number of linguists and anthropologists. Finally, the discussion deals with the question as to whether the kinship terminologies of the world all ultimately derive from a pre-dispersal African Proto-Sapiens kinship terminology. Throughout these lines of discussion, the central question is raised as to why different cultural choices on how siblings are conceptualized were made that led to different human kinship terminologies and social structures

Human kin detection

Natural selection has favored the evolution of behaviors that benefit not only one's genes, but also their copies in genetically related individuals. These behaviors include optimal outbreeding (choosing a mate that is neither too closely related, nor too distant), nepotism (helping kin), and spite (hurting non-kin at a personal cost), and all require some form of kin detection or kin recognition. Yet, kinship cannot be assessed directly; human kin detection relies on heuristic cues that take into account individuals' context (whether they were reared by our mother, or grew up in our home, or were given birth by our spouse), appearance (whether they smell or look like us), and ability to arouse certain feelings (whether we feel emotionally close to them). The uncertainties of kin detection, along with its dependence on social information, create ample opportunities for the evolution of deception and self-deception. For example, babies carry no unequivocal stamp of their biological father, but across cultures they are passionately claimed to resemble their mother's spouse; to the same effect, neutral' observers are greatly influenced by belief in relatedness when judging resemblance between strangers. Still, paternity uncertainty profoundly shapes human relationships, reducing not only the investment contributed by paternal versus maternal kin, but also prosocial behavior between individuals who are related through one or more males rather than females alone. Because of its relevance to racial discrimination and political preferences, the evolutionary pressure to prefer kin to non-kin has a manifold influence on society at large

The Enigmatic Canal-Associated Neurons Regulate Caenorhabditis elegans Larval Development Through a cAMP Signaling Pathway.

Caenorhabditis elegans larval development requires the function of the two Canal-Associated Neurons (CANs): killing the CANs by laser microsurgery or disrupting their development by mutating the gene ceh-10 results in early larval arrest. How these cells promote larval development, however, remains a mystery. In screens for mutations that bypass CAN function, we identified the gene kin-29, which encodes a member of the Salt-Inducible Kinase (SIK) family and a component of a conserved pathway that regulates various C. elegans phenotypes. Like kin-29 loss, gain-of-function mutations in genes that may act upstream of kin-29 or growth in cyclic-AMP analogs bypassed ceh-10 larval arrest, suggesting that a conserved adenylyl cyclase/PKA pathway inhibits KIN-29 to promote larval development, and that loss of CAN function results in dysregulation of KIN-29 and larval arrest. The adenylyl cyclase ACY-2 mediates CAN-dependent larval development: acy-2 mutant larvae arrested development with a similar phenotype to ceh-10 mutants, and the arrest phenotype was suppressed by mutations in kin-29 ACY-2 is expressed predominantly in the CANs, and we provide evidence that the acy-2 functions in the CANs to promote larval development. By contrast, cell-specific expression experiments suggest that kin-29 acts in both the hypodermis and neurons, but not in the CANs. Based on our findings, we propose two models for how ACY-2 activity in the CANs regulates KIN-29 in target cells

Nepotistic patterns of violent psychopathy: evidence for adaptation?

Psychopaths routinely disregard social norms by engaging in selfish, antisocial, often violent behavior. Commonly characterized as mentally disordered, recent evidence suggests that psychopaths are executing a well-functioning, if unscrupulous strategy that historically increased reproductive success at the expense of others. Natural selection ought to have favored strategies that spared close kin from harm, however, because actions affecting the fitness of genetic relatives contribute to an individual’s inclusive fitness. Conversely, there is evidence that mental disorders can disrupt psychological mechanisms designed to protect relatives. Thus, mental disorder and adaptation accounts of psychopathy generate opposing hypotheses: psychopathy should be associated with an increase in the victimization of kin in the former account but not in the latter. Contrary to the mental disorder hypothesis, we show here in a sample of 289 violent offenders that variation in psychopathy predicts a decrease in the genetic relatedness of victims to offenders; that is, psychopathy predicts an increased likelihood of harming non-relatives. Because nepotistic inhibition in violence may be caused by dispersal or kin discrimination, we examined the effects of psychopathy on (1) the dispersal of offenders and their kin and (2) sexual assault frequency (as a window on kin discrimination). Although psychopathy was negatively associated with coresidence with kin and positively associated with the commission of sexual assault, it remained negatively associated with the genetic relatedness of victims to offenders after removing cases of offenders who had coresided with kin and cases of sexual assault from the analyses. These results stand in contrast to models positing psychopathy as a pathology, and provide support for the hypothesis that psychopathy reflects an evolutionary strategy largely favoring the exploitation of non-relatives

Identifying systems barriers that may prevent bereavement service access to bereaved carers: A report from an Australian specialist palliative care service

Background: Bereavement follow up is an integral element of palliative care. However, little is known about the systems that link bereavement services with bereaved carers. Aim: To map how effectively a specialist palliative care service linked bereavement service to bereaved carers. Methodology: A retrospective medical audit, using process mapping was undertaken within one Australian specialist palliative care service to identify the systems that linked bereavement services to a consecutive cohort of palliative care decedents (n=60) next of kin. Results: Bereavement records were located for 80% of decedents. Nearly all (98%) had a nominated next of kin, with just over half (54%) of those nominated contacted by bereavement services. Incomplete or missing contact details was the main reason (75%) that the bereavement service was unable to contact the decedents’ next of kin. Conclusion: Having access to a designated bereavement service can ensure that bereaved next of kin are contract routinely and in a timely way. However the effectiveness of this type of service is dependent upon the bereavement service having access to all relevant contact information. There are numerous opportunities to refine and strengthen the recording of palliative care next of kin details to optimize follow up

Polymorphic members of the lag gene family mediate kin discrimination in Dictyostelium

Self and kin discrimination are observed in most kingdoms of life and are mediated by highly polymorphic plasma membrane proteins. Sequence polymorphism, which is essential for effective recognition, is maintained by balancing selection. Dictyostelium discoideum are social amoebas that propagate as unicellular organisms but aggregate upon starvation and form fruiting bodies with viable spores and dead stalk cells. Aggregative development exposes Dictyostelium to the perils of chimerism, including cheating, which raises questions about how the victims survive in nature and how social cooperation persists. Dictyostelids can minimize the cost of chimerism by preferential cooperation with kin, but the mechanisms of kin discrimination are largely unknown. Dictyostelium lag genes encode transmembrane proteins with multiple immunoglobulin (Ig) repeats that participate in cell adhesion and signaling. Here, we describe their role in kin discrimination. We show that lagB1 and lagC1 are highly polymorphic in natural populations and that their sequence dissimilarity correlates well with wild-strain segregation. Deleting lagB1 and lagC1 results in strain segregation in chimeras with wild-type cells, whereas elimination of the nearly invariant homolog lagD1 has no such consequences. These findings reveal an early evolutionary origin of kin discrimination and provide insight into the mechanism of social recognition and immunity

Kin and non-kin relationships of a selected group of urban families.

Thesis (M.S.)--Boston Universit

Minimal dilatations of pseudo-Anosovs generated by the magic 3-manifold and their asymptotic behavior

This paper concerns the set $\hat{\mathcal{M}}$ of pseudo-Anosovs which occur as monodromies of fibrations on manifolds obtained from the magic 3-manifold $N$ by Dehn filling three cusps with a mild restriction. We prove that for each $g$ (resp. $g \not\equiv 0 \pmod{6}$), the minimum among dilatations of elements (resp. elements with orientable invariant foliations) of $\hat{\mathcal{M}}$ defined on a closed surface $\varSigma_g$ of genus $g$ is achieved by the monodromy of some $\varSigma_g$-bundle over the circle obtained from $N(\tfrac{3}{-2})$ or $N(\tfrac{1}{-2})$ by Dehn filling two cusps. These minimizers are the same ones identified by Hironaka, Aaber-Dunfiled, Kin-Takasawa independently. In the case $g \equiv 6 \pmod{12}$ we find a new family of pseudo-Anosovs defined on $\varSigma_g$ with orientable invariant foliations obtained from N(-6) or N(4) by Dehn filling two cusps. We prove that if $\delta_g^+$ is the minimal dilatation of pseudo-Anosovs with orientable invariant foliations defined on $\varSigma_g$, then $$\limsup_{\substack{g \equiv 6 \pmod{12} g \to \infty}} g \log \delta^+_g \le 2 \log \delta(D_5) \approx 1.0870,$$ where $\delta(D_n)$ is the minimal dilatation of pseudo-Anosovs on an $n$-punctured disk. We also study monodromies of fibrations on N(1). We prove that if $\delta_{1,n}$ is the minimal dilatation of pseudo-Anosovs on a genus 1 surface with $n$ punctures, then $$\limsup_{n \to \infty} n \log \delta_{1,n} \le 2 \log \delta(D_4) \approx 1.6628.$$Comment: 46 pages, 14 figures; version 3: Major change in Section 2.1, and minor correction