Parasite-stress theory

Last updated
Schistosoma mansoni, an endoparasite that lives in human tissue Schistosoma mansoni2.jpg
Schistosoma mansoni , an endoparasite that lives in human tissue

Parasite-stress theory, or pathogen-stress theory, is a theory of human evolution proposing that parasites and diseases encountered by a species shape the development of species' values and qualities, proposed by researchers Corey Fincher and Randy Thornhill.

Contents

The differences in how parasites and diseases stress people's development is what leads to differences in their biological mate value and mate preferences, as well as differences across culture. [1] Parasites causing diseases pose potential ecological hazards and, subsequently, selection pressures can alter psychological and social behaviours of humans, as well as have an influence on their immune systems. [2]

Theories of parasite-mediated mate choice

Several hypotheses have attempted to explain how parasite load influences female mate choice, as certain traits are thought to be costly and the expression of such traits may be indicative of genetic quality.

Hamilton–Zuk hypothesis

An example of a cost the peacock must bear from having such a large tail. The tail requires a lot of energy as it weighs the peacock down during its flight. Peacock Flying.jpg
An example of a cost the peacock must bear from having such a large tail. The tail requires a lot of energy as it weighs the peacock down during its flight.

According to the Hamilton–Zuk hypothesis, [3] female mate choice is based on the extent to which male secondary sexual characteristics are expressed, as these are thought to be indicative of a heritable resistance to pathogens. A meta-analysis [4] reviewed studies exploring the magnitude of the relationship between expression of secondary sexual characteristics and parasite intensity, as well as level of host immune functioning. Consistent with the hypothesis proposed by Hamilton and Zuk, the meta-analysis revealed that males with the fewest parasites and/or the strongest immune systems typically had the most extravagant secondary sexual characteristics. With regards to parasite-stress theory, these findings would be interpreted as those men who have encountered more parasites – or are naturally less capable of dealing with parasites – are also less desirable mates to females, due to a lower genetic quality for the potential offspring. [5]

The Zahavi handicap principle

The Zahavi handicap principle, originally proposed by Zahavi in 1975, [6] suggests that males who possess secondary sexual characteristics which provide a handicap are more attractive to females. These sexual ornaments are sexually selected in order to appear stronger and better adapted, compared to other males in the environment. This is because these characteristics are indicators of good genes and heritable viability, as they are costly to an individual's survival to maintain and produce. Therefore, the stronger the individual is, the more able they are to bear this cost.[ citation needed ]

These kinds of characteristics are a form of communication within species, as they are defined as honest signals (a signal about a mate's quality which cannot be faked). As a weak individual would not be able to survive with this particular characteristic, it signals to potential mates that it is stronger than its competitors and has a high mate value. Examples of such traits include the peacock's tail, very bright in nature and hence attracting more attention from predators as well as requiring more energy to maintain. Another example is the gazelle's stotting behaviour, whereby the gazelle jumps up and down when it spots a predator, in order to indicate its physical fitness.

A gazelle stotting to indicate its fitness and ability to outrun a predator Springbok pronk.jpg
A gazelle stotting to indicate its fitness and ability to outrun a predator

Immunocompetence handicap hypothesis

This hypothesis takes Zahavi's principle further in suggesting that testosterone is responsible for the production of male secondary sexual traits while also suppressing the immune system. It therefore proposes that these traits are honest signals of mate quality because only males with 'good genes' should be able to fully express them without being vulnerable to parasite attack. [7] Males will, therefore, demonstrate their high genetic quality by developing more attractive honest signals in substitute for their immune system's strength. These honest signals require testosterone, which simultaneously suppresses the immune system. [8]

A meta-analysis revealed that evidence for a direct effect of testosterone on the expression of sexual traits and the suppression of immunocompetence was weak. It was found, however, that increased testosterone influenced parasite loads, indicating an indirect role of the hormone in immune function. [9]

Parasite-mediated domestication

According to the parasite-mediated domestication hypothesis, proposed by Skok in 2023, parasites (specifically endoparasites: helminths and protozoa) could play an important mediating role in the process of domestication, with a 'parasite effect' primarily involved in the emergence of the domesticated state (proto-domestication). The hypothesis states that parasites indirectly influence literally all of the main processes that otherwise underlie the domestication syndrome (abnormalities in the functioning of the neuro-neuroendocrine system, a developmental disruption of neural crest cell input to the affected phenotypic traits, etc.). The hypothesis predicts that the frequency of domestication syndrome traits such as tameness, depigmentation and mottling, floppy ears, short and curled tail, and reduced size of the adrenal glands from the wild population increases with decreasing genetic resistance to parasites and with increasing parasite load. The hypothesis further suggests that the features of the domestication syndrome may be genetically linked to genes related to resistance or tolerance to parasites, the role of miRNA in the process of epigenetic inheritance or the transgenerational inheritance of stress pathology. [10] [11]

Interactions with developmental instability

Developmental instability is the inability of an organism to produce its optimal phenotype, due to genetic limitations and environmental stresses (such as parasite load).

Fluctuating asymmetry

Fluctuating asymmetry is the extent to which an organism deviates from perfect body symmetry. Asymmetry, an indicator of development, is exhibited by all organisms and is thus considered by scientists to be a reliable measure of developmental instability.

Research in a Dominican village, which measured the prevalence of protozoa and worm parasites in over 300 children, found a positive correlation between gut parasites and fluctuating asymmetry. This finding is indicative of how parasites negatively impact peoples' development and act as environmental stress factors. [12]

A barn swallow Barn swallow (Hirundo rustica rustica).jpg
A barn swallow

A literature review summarising more than 100 different studies in the field found that, among other variables, immunocompetence (the ability of an organism to produce a normal immune response to an antigen) had a significant relationship with fluctuating asymmetry. In other words, individuals who had a better ability to defend themselves against threats, such as parasites, were also lower in fluctuating asymmetry. [13]

Waist-hip ratio

Waist-hip ratio is the ratio of the circumference of the waist, to the circumference of the hips. It is calculated by dividing the waist circumference by the hip circumference.[ citation needed ]

A woman's waist-hip ratio is an indicator of her age, health and fertility, as well as being a good indicator of other people's judgements of attractiveness, with a lower waist-hip ratio being optimal. [14] All of the above are related to mate choice: a lower waist-hip ratio indicates a younger, healthier, more fertile and more subjectively attractive women, all of which are desirable qualities in a mate.

Higher waist-hip ratio has been linked with both mobility disability and also cardiovascular disease. [15] Also, within parasite-stress theory itself, women with higher waist-hip ratio's also had a higher incidence of toxoplasmosis, another incidence in which parasitism contributes to developmental instability. [16]

Mate choice

Mate choosers prefer mates who are lower in developmental instability, meaning that they choose those who display lower fluctuating asymmetry.

In barn swallows, the length of the male's tail is used as a signal of mate quality: males with longer tails are preferred to those with shorter tails. Research has found that, in a population of barn swallows infested by the parasite Ornithonyssus bursa , male barn swallows with fewer mites also had longer tails. [17]

Variations across cultures

When discussing cross-cultural differences between societies, scientists will more often than not make a distinction between individualism and collectivism. [18] Consequently, it is important to provide an understanding for the variations exhibited between these two cultures.[ citation needed ]

Collectivist

Research has suggested that collectivism exists to defend against infectious diseases. [1] Therefore, cultures that have a higher rate of infections will be more likely to become collectivist. This has been based on a number of observations.

Firstly, collectivists place a lot of emphasis on their in-group, caring for one another and hence protecting each other from the negative effects of contagion. This is likely due to the fact that one's immune system works to defend the body from local parasites; however, this still allows for the risk of unfamiliar infections resulting in illness [19] as the immune system has not been able to evolve in response to these novel parasites. Hence, ensuring that those in the in-group are not affected by a novel disease will subsequently result in a reduced risk of encountering a novel parasite from an exposed person an individual remains in close proximity with.

Secondly, collectivist cultures are untrusting of those outside of their in-group, which may serve as a protective behaviour against interactions with those in groups that may harbour novel diseases. In similar vein to the explanation presented with one's protective nature of their in-group members, one's immune system is well adapted to local parasites and will be unable to effectively protect against unfamiliar pathogens. Therefore, avoidance of those outside of one's inner circle will aid in the prevention of being exposed to novel and dangerous pathogens that the immune system is unable to defend against.

Thirdly, it has been observed that collectivist groups exhibit strong negative attitudes when an individual goes against their social norms. A relevant example is deviating from the way that food is prepared, [20] which could result in a higher possibility of exposure to new and threatening pathogens. Hence, this strong social norm, is effectively in place to prevent group members from being negligent and becoming ill with a novel parasite – which then could pass onto other members of the group.

Individualist

Individualist societies, however, are very different to collectivist through their promotion of looking out for oneself, rather than worrying about the needs of the group. This is partly due to these cultures being predominantly in geographical locations which are under a lot less danger from parasite invasions. Unlike collectivists, individualists make much less of a distinction between in-groups and out-groups. [21] A clear distinction, that individualism shows from collectivism, comes from the active encouragement individualist cultures place upon individuals straying from the current social norms. [2]

Criticism

Some authors have pointed out that parasite stress is a misleading term because the described phenomenon includes viruses. A virus does not fit the definition of a parasite because a parasite is defined as an organism, and a virus is not an organism. [22] Some authors use the name pathogen-stress theory instead. [23]

Several scientists have criticized the theory that pathogen stress can explain differences in collectivism versus individualism, suggesting that the observed correlations were spurious. [24] [25] Anthropologist Daniel Hruschka and human biologist Joseph Henrich have proposed an alternative explanation of the observed cultural differences. In colonial times, European colonizers established efficient social institutions in countries with low mortality. In places where mortality was high due to infectious diseases, they set up extractive systems with less settling of Europeans. The more-efficient government institutions inherited from colonial times in low mortality countries can explain the observed differences in cultural values. [26]

Parasite influence on food preference across cultures

This difference in culture due to pathogen avoidance has also been seen in the contrast of food preferences between cultures. [20] Research investigated the possibility that individuals will have a preference for spices in their cooking to defend against food-borne human parasites. This was tested through measuring the types and numbers of spices used in recipes across various regions across the world – it was found that temperature was a good predictor of the use of anti-pathogen spices. This finding makes sense when considering that temperature is a breeding ground for parasites. [27]

See also

Related Research Articles

<span class="mw-page-title-main">Sexual selection</span> Mode of natural selection involving the choosing of and competition for mates

Sexual selection is a mode of natural selection in which members of one biological sex choose mates of the other sex to mate with, and compete with members of the same sex for access to members of the opposite sex. These two forms of selection mean that some individuals have greater reproductive success than others within a population, for example because they are more attractive or prefer more attractive partners to produce offspring. Successful males benefit from frequent mating and monopolizing access to one or more fertile females. Females can maximise the return on the energy they invest in reproduction by selecting and mating with the best males.

<span class="mw-page-title-main">Handicap principle</span> Hypothesis in evolutionary biology

The handicap principle is a disputed hypothesis proposed by the Israeli biologist Amotz Zahavi in 1975. It is meant to explain how sexual selection may lead to "honest" or reliable signalling between male and female animals which have an obvious motivation to bluff or deceive each other. The handicap principle suggests that secondary sexual characteristics are costly signals which must be reliable, as they cost the signaller resources that individuals with less of a particular trait could not afford. The handicap principle further proposes that animals of greater biological fitness signal this through handicapping behaviour, or morphology that effectively lowers overall fitness. The central idea is that sexually selected traits function like conspicuous consumption, signalling the ability to afford to squander a resource. Receivers then know that the signal indicates quality, because inferior-quality signallers are unable to produce such wastefully extravagant signals.

<span class="mw-page-title-main">Signalling theory</span> Theory in evolutionary biology

Within evolutionary biology, signalling theory is a body of theoretical work examining communication between individuals, both within species and across species. The central question is when organisms with conflicting interests, such as in sexual selection, should be expected to provide honest signals rather than cheating. Mathematical models describe how signalling can contribute to an evolutionarily stable strategy.

<span class="mw-page-title-main">Fluctuating asymmetry</span> Form of biological asymmetry

Fluctuating asymmetry (FA), is a form of biological asymmetry, along with anti-symmetry and direction asymmetry. Fluctuating asymmetry refers to small, random deviations away from perfect bilateral symmetry. This deviation from perfection is thought to reflect the genetic and environmental pressures experienced throughout development, with greater pressures resulting in higher levels of asymmetry. Examples of FA in the human body include unequal sizes (asymmetry) of bilateral features in the face and body, such as left and right eyes, ears, wrists, breasts, testicles, and thighs.

<span class="mw-page-title-main">Psychological adaptation</span>

A psychological adaptation is a functional, cognitive or behavioral trait that benefits an organism in its environment. Psychological adaptations fall under the scope of evolved psychological mechanisms (EPMs), however, EPMs refer to a less restricted set. Psychological adaptations include only the functional traits that increase the fitness of an organism, while EPMs refer to any psychological mechanism that developed through the processes of evolution. These additional EPMs are the by-product traits of a species’ evolutionary development, as well as the vestigial traits that no longer benefit the species’ fitness. It can be difficult to tell whether a trait is vestigial or not, so some literature is more lenient and refers to vestigial traits as adaptations, even though they may no longer have adaptive functionality. For example, xenophobic attitudes and behaviors, some have claimed, appear to have certain EPM influences relating to disease aversion, however, in many environments these behaviors will have a detrimental effect on a person's fitness. The principles of psychological adaptation rely on Darwin's theory of evolution and are important to the fields of evolutionary psychology, biology, and cognitive science.

<span class="mw-page-title-main">Waist–hip ratio</span>

The waist–hip ratio or waist-to-hip ratio (WHR) is the dimensionless ratio of the circumference of the waist to that of the hips. This is calculated as waist measurement divided by hip measurement. For example, a person with a 75 cm waist and 95 cm hips has WHR of about 0.79.

<span class="mw-page-title-main">Mate choice</span> One of the primary mechanisms under which evolution can occur

Mate choice is one of the primary mechanisms under which evolution can occur. It is characterized by a "selective response by animals to particular stimuli" which can be observed as behavior. In other words, before an animal engages with a potential mate, they first evaluate various aspects of that mate which are indicative of quality—such as the resources or phenotypes they have—and evaluate whether or not those particular trait(s) are somehow beneficial to them. The evaluation will then incur a response of some sort.

<span class="mw-page-title-main">Lek paradox</span>

The lek paradox is the conundrum of how additive or beneficial genetic variation is maintained in lek mating species in the face of consistent sexual selection based on female preferences. While many studies have attempted to explain how the lek paradox fits into Darwinian theory, the paradox remains. Persistent female choice for particular male trait values should erode genetic diversity in male traits and thereby remove the benefits of choice, yet choice persists. This paradox can be somewhat alleviated by the occurrence of mutations introducing potential differences, as well as the possibility that traits of interest have more or less favorable recessive alleles.

<span class="mw-page-title-main">Behavioral immune system</span>

The behavioral immune system is a phrase coined by the psychological scientist Mark Schaller to refer to a suite of psychological mechanisms that allow individual organisms to detect the potential presence of infectious parasites or pathogens in their immediate environment, and to engage in behaviors that prevent contact with those objects and individuals.

Host–parasite coevolution is a special case of coevolution, where a host and a parasite continually adapt to each other. This can create an evolutionary arms race between them. A more benign possibility is of an evolutionary trade-off between transmission and virulence in the parasite, as if it kills its host too quickly, the parasite will not be able to reproduce either. Another theory, the Red Queen hypothesis, proposes that since both host and parasite have to keep on evolving to keep up with each other, and since sexual reproduction continually creates new combinations of genes, parasitism favours sexual reproduction in the host.

Ecoimmunology or Ecological Immunology is the study of the causes and consequences of variation in immunity. The field of ecoimmunology seeks to give an ultimate perspective for proximate mechanisms of immunology. This approach places immunology in evolutionary and ecological contexts across all levels of biological organization.

A biological ornament is a characteristic of an animal that appears to serve a decorative function rather than a utilitarian function. Many are secondary sexual characteristics, and others appear on young birds during the period when they are dependent on being fed by their parents. Ornaments are used in displays to attract mates, which may lead to the evolutionary process known as sexual selection. An animal may shake, lengthen, or spread out its ornament in order to get the attention of the opposite sex, which will in turn choose the most attractive one with which to mate. Ornaments are most often observed in males, and choosing an extravagantly ornamented male benefits females as the genes that produce the ornament will be passed on to her offspring, increasing their own reproductive fitness. As Ronald Fisher noted, the male offspring will inherit the ornament while the female offspring will inherit the preference for said ornament, which can lead to a positive feedback loop known as a Fisherian runaway. These structures serve as cues to animal sexual behaviour, that is, they are sensory signals that affect mating responses. Therefore, ornamental traits are often selected by mate choice.

<span class="mw-page-title-main">Major histocompatibility complex and sexual selection</span> Adaptive immune gene selection

The major histocompatibility complex in sexual selection concerns how major histocompatibility complex (MHC) molecules allow for immune system surveillance of the population of protein molecules in a host's cells. In 1976, Yamazaki et al. demonstrated a sexual selection mate choice by male mice for females of a different MHC.

<span class="mw-page-title-main">Randy Thornhill</span> American entomologist and evolutionary biologist (born 1944)

Randy Thornhill is an American entomologist and evolutionary biologist. He is a professor of biology at the University of New Mexico, and was president of the Human Behavior and Evolution Society from 2011 to 2013. He is known for his evolutionary explanation of rape as well as his work on insect mating systems and the parasite-stress theory.

Mate preferences in humans refers to why one human chooses or chooses not to mate with another human and their reasoning why. Men and women have been observed having different criteria as what makes a good or ideal mate. A potential mate's socioeconomic status has also been seen important, especially in developing areas where social status is more emphasized.

The evolution of schizophrenia refers to the theory of natural selection working in favor of selecting traits that are characteristic of the disorder. Positive symptoms are features that are not present in healthy individuals but appear as a result of the disease process. These include visual and/or auditory hallucinations, delusions, paranoia, and major thought disorders. Negative symptoms refer to features that are normally present but are reduced or absent as a result of the disease process, including social withdrawal, apathy, anhedonia, alogia, and behavioral perseveration. Cognitive symptoms of schizophrenia involve disturbances in executive functions, working memory impairment, and inability to sustain attention.

<span class="mw-page-title-main">Human mating strategies</span> Courtship behavior of humans

In evolutionary psychology and behavioral ecology, human mating strategies are a set of behaviors used by individuals to select, attract, and retain mates. Mating strategies overlap with reproductive strategies, which encompass a broader set of behaviors involving the timing of reproduction and the trade-off between quantity and quality of offspring.

Pathogen avoidance, also referred to as, parasite avoidance or pathogen disgust, refers to the theory that the disgust response, in humans, is an adaptive system that guides behavior to avoid infection caused by parasites such as viruses, bacteria, fungi, protozoa, helminth worms, arthropods and social parasites. Pathogen avoidance is a psychological mechanism associated with the behavioral immune system. Pathogen avoidance has been discussed as one of the three domains of disgust which also include sexual and moral disgust.

Bogusław Pawłowski is a Polish biologist and professor of biological sciences at the University of Wrocław. President of European Human Behaviour and Evolution Association (EHBEA).

In humans, males and females differ in their strategies to acquire mates and focus on certain qualities. There are two main categories of strategies that both sexes utilize: short-term and long-term. Human mate choice, an aspect of sexual selection in humans, depends on a variety of factors, such as ecology, demography, access to resources, rank/social standing, genes, and parasite stress.

References

  1. 1 2 Thornhill, Randy; Fincher, Corey (2014). The Parasite-Stress Theory of Values and Sociality. New York: Springer. pp. 59–63. ISBN   978-3-319-08039-0.
  2. 1 2 Fincher, C.; Thornhill, R.; Murray, D.R.; Schaller, M. (2008). "Pathogen prevalence predicts human cross-cultural variability in individualism/collectivism". Proceedings of the Royal Society B: Biological Sciences. 275 (1640): 1279–1285. doi:10.1098/rspb.2008.0094. PMC   2602680 . PMID   18302996.
  3. ↑ Hamilton, William; Zuk, Marlene (1982). "Heritable True Fitness and Bright Birds: A Role for Parasites?" (PDF). Science. 218 (4570): 384–387. Bibcode:1982Sci...218..384H. doi:10.1126/science.7123238. PMID   7123238 . Retrieved 2 March 2016.
  4. ↑ Moller, A.P; Christe, P; Lux, E (1999). "Parasitism, Host Immune Function, and Sexual Selection". The Quarterly Review of Biology. 74 (1): 3–20. doi:10.1086/392949. PMID   10081812. S2CID   27662561 . Retrieved 2 March 2016.
  5. ↑ Pazhoohi, F.; Kingstone, A. (2020). "Parasite prevalence and income inequality positively predict beardedness across 25 countries". Adaptive Human Behavior and Physiology. 6 (2): 185–193. doi:10.1007/s40750-020-00132-6.
  6. ↑ Zahavi, Amotz (1975). "Mate selection - a selection for a handicap". Journal of Theoretical Biology. 53 (1): 205–214. Bibcode:1975JThBi..53..205Z. CiteSeerX   10.1.1.586.3819 . doi:10.1016/0022-5193(75)90111-3. PMID   1195756.
  7. ↑ Owen-Ashley, Noah T.; Hasselquist, Dennis; Wingfield, John& C.; Ketterson, Ellen D. (2004-01-01). "Androgens and the Immunocompetence Handicap Hypothesis: Unraveling Direct and Indirect Pathways of Immunosuppression in Song Sparrows" (PDF). The American Naturalist. 164 (4): 490–505. doi:10.1086/423714. JSTOR   10.1086/423714. PMID   15459880. S2CID   10703846.
  8. ↑ Folstad, Ivar; Karter, Andrew John (1992). "Parasites, Bright males and the Immunocompetence Handicap". The American Naturalist. 139 (3): 603. doi:10.1086/285346. S2CID   85266542.
  9. ↑ Roberts, M. L.; Buchanan, K. L.; Evans, M. R. (2004-08-01). "Testing the immunocompetence handicap hypothesis: a review of the evidence". Animal Behaviour. 68 (2): 227–239. doi:10.1016/j.anbehav.2004.05.001. S2CID   9549459.
  10. ↑ Skok, J. (2023). "The Parasite-Mediated Domestication Hypothesis". Agricultura Scientia. 20 (1): 1–7. doi: 10.18690/agricsci.20.1.1 .
  11. ↑ Skok, J. (2023). "Addendum to 'The parasite-mediated domestication hypothesis'". OSF. doi: 10.31219/osf.io/f92aj .
  12. ↑ Worthen, CC (2001). "Parasite load, growth, fluctuating asymmetry, and stress hormone profiles among children in a rural Caribbean village". American Journal of Physical Anthropology. 114: 153–170. doi:10.1002/ajpa.1040.
  13. ↑ Van Dongen, Stefan; Gangestad, Steven (2011). "Human fluctuating asymmetry in relation to health and quality: A meta-analysis". Evolution and Human Behavior. 32 (6): 380–398. doi:10.1016/j.evolhumbehav.2011.03.002.
  14. ↑ Singh, Devendra; Randall, Patrick (2007). "Beauty is in the eye of the plastic surgeon: Waist-hip ratio (WHR) and women's attractiveness". Personality and Individual Differences. 43 (2): 329–340. doi:10.1016/j.paid.2006.12.003.
  15. ↑ Singh, Tushar (2015). "Cardiovascular disease and mobility disability in rural older indians: The mobility and independent living in elders study (MILES)". Information & Learning.
  16. ↑ Flegr, J (2005). "Body height, body mass index, waist-hip ratio, fluctuating asymmetry and second to fourth digit ratio in subjects with latent toxoplasmosis". Parasitology. 130 (6): 621–628. doi:10.1017/s0031182005007316. PMID   15977898. S2CID   7320739.
  17. ↑ Moller, A.P. (2002). "Temporal change in mite abundance and its effect on barn swallow reproduction and sexual selection". Journal of Evolutionary Biology. 15 (3): 495–504. doi:10.1046/j.1420-9101.2002.00386.x. S2CID   82842331.
  18. ↑ Hofstede, G. (2001). Consequences: Comparing Values, Behaviors, Institutions, and Organizations Across Nations. Thousand Oaks, CA.: Sage Publications. pp. 113–114.
  19. ↑ Fincher, C.; Thornhill, R. (2008a). "A parasite-driven wedge: Infectious diseases may explain language and other biodiversity". Oikos. 117 (9): 1289–1297. doi:10.1111/j.0030-1299.2008.16684.x.
  20. 1 2 Sherman, P.W.; Billing, J. (1999). "Darwinian gastronomy: Why we use spices". BioScience. 49 (6): 453–463. doi: 10.2307/1313553 . JSTOR   1313553.
  21. ↑ Gelfand, M.J.; Bhawuk, D.P.S.; Nishii, L.H.; Bechtold, D.J. (2004). "Individualism and Collectivism". In Robert J. House; Paul J. Hanges; Mansour Javidan; Peter W. Dorfman; Vipin Gupta (eds.). Culture, leadership, and organizations: the GLOBE study of 62 societies. Thousand Oaks, CA: Sage Publications. pp. 437–512.
  22. ↑ Fog, Agner (2023). "Psychological and cultural effects of different kinds of danger. An exploration based on survey data from 79 countries". Culture and Evolution (2023). doi: 10.1556/2055.2023.00029 .
  23. ↑ Lu, You-Hai; et al. (2022). "Understanding regional mobility resilience and its relationship with regional culture during the COVID-19 pandemic: A pathogen-stress theory perspective". Journal of Cleaner Production. 339: 130621. doi:10.1016/j.jclepro.2022.130621. PMC   8772349 . PMID   35079209.
  24. ↑ Bromham, Lindell (2018). "Parasites and politics: why cross-cultural studies must control for relatedness, proximity and covariation". Royal Society Open Science. 5 (8): 181100. Bibcode:2018RSOS....581100B. doi:10.1098/rsos.181100. PMC   6124128 . PMID   30225088.
  25. ↑ Currie, Thomas E.; Mace, Ruth (2012). "Analyses do not support the parasite-stress theory of human sociality" (PDF). Behavioral and Brain Sciences. 35 (2): 83–85. doi:10.1017/S0140525X11000963. PMID   22289294. S2CID   302233.
  26. ↑ Hruschka, Daniel J.; Henrich, Joseph (2013). "Institutions, Parasites and the Persistence of In-group Preferences". PLOS ONE. 8 (5): e63642. Bibcode:2013PLoSO...863642H. doi: 10.1371/journal.pone.0063642 . PMC   3660589 . PMID   23704926.
  27. ↑ Billing, J.; Sherman, P. W. (1998). "Antimicrobial functions of spices: Why some like it hot". Quarterly Review of Biology. 73 (1): 3–49. doi:10.1086/420058. PMID   9586227. S2CID   22420170.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.