The ‘size-advantage’ hypothesis for plant competition — rejected

  Plants with larger body size generally have lower fitness under severe competition.

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The blue-flowered species has a larger maximum potential body size, but also must reach a larger size before it can reproduce at all — i.e. it has a larger minimum reproductive threshold size. In a severely crowded neighbourhood, therefore (represented here), very few offspring ever reach this minimum size and so they die without sex. In contrast, many offspring produced by the smaller red-flowered species — despite also being strongly suppressed by competition — manage to produce at least some grand-offspring, simply because they have a much smaller minimum reproductive threshold size.

Within most natural vegetation, resources are routinely and strongly contested between near neighbours of both the same and different species. According to conventional theory, the selection consequences of this sustained competition have been interpreted mostly in terms of a ‘size-advantage’ hypothesis — i.e. under severe neighbourhood crowding / competition, natural selection generally favours capacity (through pre-emptive, rapid and/or prolonged resource capture) for growth to a body size that is relatively large (e.g. Grime 1979; Keddy 1989, Grace 1990; Goldberg 1996). The precise physiological and morphological mechanisms of resource competition (particularly below-ground) may not always be size-related (Craine 2009). Nevertheless, since resources (water, soil nutrients, quanta of sunlight, etc) are always spatially (and temporally) distributed, it follows that a plant occupying more space (and over a longer time), both above and below ground, will generally be better equipped to acquire these resources and thus deny them to neighbours. An individual that manages to attain this relatively large body size (while neighbouring plants fail to do so) will thus, inevitably, be expected to achieve greater reproductive output. 

Results from recent empirical research, however, call into question the size-advantage hypothesis. If larger plant species are generally expected to exclude smaller ones when there is persistent crowding/competition, then neighbouring species should generally be more similar in body size than would be expected by random assembly, based on the local species pool. Yet several studies have failed to find evidence for this, including in grasslands (Schamp et al. 2011), old-field vegetation (Schamp, Chau & Aarssen 2008), wetlands (Weiher et al. 1998), temperate forests (Schamp & Aarssen 2009), tropical forests (Swenson & Enquist 2009), and coastal sand-dune succession (Waugh & Aarssen 2012). Larger species in crowded woody vegetation (Keating & Aarssen 2009), as well as in crowded herbaceous vegetation (Schamp et al. 2013, Aarssen et al. 2014), are not more likely than smaller species, to limit the resident species density within their immediate neighbourhoods, nor are they more likely to limit the representation of relatively small resident species. Bonser and Ladd (2011) similarly found that vegetative size was not a strong predictor of success under competition in annuals species; more important was the capacity to reproduce efficiently in the presence of competitors. Finally, a recent survey of published literature (Bonser 2013)—including for both short-lived semelparous and potentially longer-lived iteroparous species—showed that the efficiency of conversion of resources from vegetative tissue to reproductive output is generally higher (not lower) when competition levels increase, contrary to traditional life history theory.

When neighbourhood resources are strongly and persistently contested, therefore, there is apparently no general advantage (in terms of recruitment success or relative abundance within the habitat) for the offspring of species that are capable of (i.e. because they have evolved) relatively large potential body size (relative to the offspring of neighbouring species that have not evolved a large potential body size) (Tracey and Aarssen 2011, 2014). The vast majority of plant species everywhere are in fact relatively small; i.e. plant species body size distributions are right-skewed within every phylogenetic lineage, and for resident species at every spatial scale — from regional floras down to local neighbourhoods (Aarssen & Schamp 2002, Niklas et al. 2003, Aarssen et al. 2006, Poorter et al. 2008, Moles et al. 2009, Schamp & Aarssen 2009, McGlone et al. 2010, Dombroskie & Aarssen 2010, Tracey & Aarssen 2011). And importantly this is also true even within habitat types traditionally characterized as having the strongest competition effects imposed on resident species.

There is sufficient evidence, therefore, to reject the size-advantage hypothesis, and hence a need to replace it with revised model predictions for body size evolution in plants. The latter, I suggest, should begin with a now largely validated generalization: there is a fundamental between-species trade-off between maximum potential body size (MAX) and the capacity to reproduce when forced to remain small, i.e. minimum reproductive threshold size (MIN). This has long been evident anecdotally for woody vegetation (and see Thomas 1996, Davies & Ashton 1999), but has only recently been reported from empirical studies in herbaceous vegetation, including for the resident species within a single community (Tracey & Aarssen 2011, 2014, Nishizawa & Aarssen 2014). This ‘cost’ of relatively large body size likely reflects the need for generally greater investment in structural support tissue, and also structural or chemical defense against consumers — thus enabling the longevity (survival/growth time) needed in order to reach a large body size (Taylor et al 1990). This has implications for the interpretation of body size variation not just between habitat types — but also within a single community of interacting species.

Herein then lies a profound and largely overlooked implication for plant competition theory: if a larger species generally also needs to grow to a larger threshold size before it can reproduce at all, the latter may not be generally attainable in neighbourhoods with severe and persistent crowding / competition. Larger species, therefore, can certainly be successful competitors in terms of denying contested resources to neighbours, but not if they are unable to get large. And there can be no fitness (gene transmission) advantage at all in having a large body size unless the plant can reach, at least, its relatively large MIN. Accordingly, as argued below, it turns out that larger resident species within a plant community are not usually superior competitors when it really matters — in the most severely crowded neighbourhoods.

The 'reproductive economy advantage' hypothesis for plant competition.   

In the illustration above, hypothetical plants (genotypes or species) A, B, and C are represented by differently colored circles (white/gray/black) within three square ‘plots’ showing different neighborhood densities of resident seeds, which is the only stage in which the three plants – as embryos – are all the same size. In each case, the ‘stickplant’ symbols represent the relative body sizes of A, B, and C following emergence and growth to final developmental stage. The maximum potential body sizes (MAX) for A, B, and C can be expressed only when neighborhood density is very low (top row), where A has the largest MAX and hence the highest fecundity (represented by small red circles), and where it is thus favored by natural selection. Plant A therefore also has (as a trade-off) the largest minimum reproductive threshold size (MIN), which is expressed within a higher (intermediate)-density neighborhood (middle row). Here, plant B is favored by natural selection because its smaller MIN permits a higher fecundity than A, and its larger MAX permits a higher fecundity than C. Under very high neighbor density (bottom row), however, where all resident plants are severely suppressed in size, plant C has the highest fecundity because it has the smallest MIN (which imposes, as a trade-off, the smallest MAX) (Tracey and Aarssen 2014). Under these conditions, plants of both A and B die without sex because MIN for both is too large. Selection thus favours plant C because it has greater ‘reproductive economy’ — i.e. capacity to produce offspring that can survive long enough to produce at least some grand-offspring, while nevertheless remaining with a severely suppressed body size, even until death (Aarssen 2008).

Contrary to the ‘size-advantage’ hypothesis, therefore, selection in favor of relatively large MAX (plant A) occurs, not under the most crowded conditions, but only within local neighborhoods where competition effects are relatively weak (top row) — because only here can MAX (and its potential fitness advantage) be realized. The preponderance of relatively small resident species within most natural vegetation, therefore, can be at least partially accounted for by a preponderance there of severely crowded neighborhoods (bottom row).

Importantly here, success under severe competition is defined not just (or even most importantly) by capacity to capture resources and deny them to neighbours, but more fundamentally by the capacity to transmit genes to future generations, despite severe resource deprivation by neighbours. For this latter capacity, a growing body of evidence is pointing to an alternative hypothesis based on ‘reproductive economy advantage’: under conditions of extreme and protracted neighbourhood crowding/competition (where virtually all resident plants are necessarily forced to remain, until death, at only a small fraction of their maximum potential body sizes), it is the relatively small species that are more likely to leave descendants here — simply because they need to reach only a relatively small body size in order to produce at least some offspring. Resident plants of most larger species, however, are more likely to die here producing none at all.


References


Aarssen, L.W. (2008) Death without sex — the ‘problem of the small’ and selection for reproductive economy in flowering plants. Evolutionary Ecology, 22, 279–298.

Aarssen, L.W., Schamp, B.S. (2002) Predicting distributions of species richness and species size in regional floras: applying the species pool hypothesis to the habitat template model. Perspectives in Plant Ecology, Evolution and Systematics, 5, 3–12.

Aarssen, L.W., Schamp, B.S., Pither, J. (2006) Why are there so many small plants? Implications for species coexistence. Journal of Ecology, 94, 569–580.

Aarssen, L.W., Schamp, B.S., Wight, S. (2014) Big plants — do they affect neighbourhood species richness and composition in herbaceous vegetation? Acta Oecologica, 55, 36-42.

Bonser, S.P. (2013) High reproductive efficiency as an adaptive strategy in competitive environments. Functional Ecology, 27, 876–885.

Bonser, S.P., Ladd, B. (2011) The evolution of competitive strategies in annual plants. Plant Ecology, 212, 1441-1449.

Craine, J.M. (2009) Resource Strategies of Wild Plants. Princeton: Princeton University Press.

Davies, S.J., Ashton, P.S. (1999) Phenology and fecundity in 11 sympatric pioneer species of Macaranga (Euphorbiaceae) in Borneo. American Journal of Botany 86, 1786–95.

Dombroskie, S.L., Aarssen, L.W. (2010) Within-genus size distributions in angiosperms: small is better. Perspectives in Plant Ecology, Evolution and Systematics, 12, 283–293.

Grace, J.B. (1990) On the relationship between plant traits and competitive ability. In: Grace J.B. & Tilman, D. (eds). Perspectives on Plant Competition. San Diego, Texas: Academic Press, pp.384-385.

Goldberg, D.E. (1996) Competitive ability: definitions, contingency and correlated traits. Proceedings of Royal Society B: Biological Sciences, 35, 1377–1385.

Grime, J.P. (1979) Plant Strategies and Vegetation Processes. Wiley, New York.

Keating, L.M., Aarssen, L.W. (2009) Big plants—do they limit species coexistence? Journal of Plant Ecology, 2, 119-124.

Keddy, P.A. (1989) Competition, 2nd Edition. New York: Chapman and Hall, 202 pp.

McGlone, M.S., Richardson, S.J., Jordan, G.J. (2010) Comparative biogeography of New Zealand trees: species richness, height, leaf traits and range sizes. New Zealand Journal of Ecology, 34, 137–151.

Moles, A.T., Warton, D.I., Warman, L., Swenson, N.G., Laffan, S.W., Zanne, A.E., Pitman, A., Hemmings, F.A., Frank, A., Leishman, M.R. (2009) Global patterns in plant height. Journal of Ecology, 97, 923–932.

Niklas, K.J., Midgley, J.J., Rand, R.H. (2003) Size dependent species richness: trends within plant communities and across latitude. Ecology Letters, 6, 631–636.

Nishizawa, T., Aarssen, L.W. (2014) The relationship between individual seed quality and maternal plant body size in crowded herbaceous vegetation. Journal of Plant Ecology, doi:10.1093/jpe/rtt042

Poorter, L., Hawthorne, W., Bongers, F., Sheil, D. (2008) Maximum size distributions in tropical forest communities: relationships with rainfall and disturbance. Journal of Ecology, 96, 495–504.

Schamp, B.S., Aarssen, L.W. (2009) The assembly of forest communities according to maximum species height along resource and disturbance gradients. Oikos, 118, 564–72.

Schamp, B.S., Chau, J., Aarssen, L.W. (2008) Dispersion of traits related to competitive ability in an old-field plant community. Journal of Ecology, 96, 204-212.

Schamp, B.S., Hettenbergerová, H., Hájek, M. (2011) Testing community assembly predictions for nominal and continuous plant traits in species-rich grasslands. Preslia, 83, 329‒346.

Schamp, B.S., Aarssen, L.W., Wight, S. (2013) Effects of ‘target’ plant species body size on neighbourhood species richness and composition in old-field vegetation. PLoS ONE, 8(12), e82036. doi:10.1371/journal.pone.0082036

Swenson, N.G., Enquist, B.J. (2009) Opposing assembly mechanisms in a Neotropical dry forest: implications for phylogenetic and functional community ecology. Ecology, 90, 2161– 2170.

Taylor, D.R., Aarssen, L.W., Loehle, C. (1990) On the relationship between r/K - selection and environmental carrying capacity: A new habitat templet for plant life history strategies. Oikos, 58, 239-250.

Thomas, S.C. (1996) Relative size at onset of maturity in rain forest trees: a comparative analysis of 37 Malaysian species. Oikos, 76, 145–54.

Tracey, A.J., Aarssen, L.W. (2011) Competition and body size in plants: the between-species trade-off in maximum potential versus minimum reproductive threshold size. Journal of Plant Ecology, 4, 115-122.

Tracey, A.J., Aarssen, L.W. (2014) Revising traditional theory on the link between plant body-size and fitness under competition: evidence from old-field vegetation. Ecology and Evolution, 4, 959–967.

Waugh, J.M., Aarssen, L.W. (2012) Size distributions and dispersions along a 485-year chronosequence for sand dune vegetation. Ecology and Evolution, 2, 719–726.

Weiher, E., Clarke, G.D.P., Keddy, P.A. (1998) Community assembly rules, morphological dispersion, and the coexistence of plant species. Oikos, 81, 309‒322.

The 'Work Hard – Play Hard' Hypothesis

'Work hard – play hard' is a familiar slogan in popular culture. Its origin is uncertain but it can be traced to at least 1884 in an advertisement for Racine College — a 19th Century Episcopal preparatory school in Racine, Wisconsin — where it is attributed to its first Warden, James deKoven within the motto "Work hard, Play hard, Pray hard." (Brotherhood 2011, p. 88). The traditional inference involves a work ethic, with the principal focus on virtue in hard work, and connecting this (secondarily it seems) to associated value in play or leisure — enjoyable free-time pursuits.

An interesting question is whether this is meant merely as a kind of prescription or manifesto for a cultural norm or lifestyle — effected through social learning — to indulge in leisure following (as an earned reward for, or to motivate additional) hard work. Perhaps it serves to extol a kind of 'work-life' balance or blend, thus recommending (for one's well-being) against 'all work and no play'.

Or perhaps 'work hard – play hard' refers to an assumed, perceived, or expected association between two fundamental human penchants across a range of phenotypic variation (without any particular precedence of one necessarily needing to follow or to be evoked/triggered by the other). In other words, perhaps — interacting with effects of environment / social learning — there are deeply ingrained personality traits that drive one to work hard, and that these tend generally to be correlated with personality traits (also deeply ingrained) that drive one to play hard. 

Or perhaps their alleged positive relationship is largely mythical, or weak at best. In addition to the slogan's meaning or why it exists, even more fundamentally the question remains as to the extent that 'working hard' and 'playing hard' tend in fact to be found together in representing the interests and motivations of resident individuals within a population. Even clear anecdotal evidence is hard to find.

To address this question, recently I designed a survey study together with student, Laura Crimi, involving a large sample population of Queen’s University undergraduates. Volunteer participants were presented with series of questions designed to detect variation in levels of attraction to both accomplishment/fame (or 'work'), and leisure/recreation (or 'play'’). The study also included other questions about preferences and interests, but in this post I will focus only on the most striking result: strong and novel support for the ‘work hard – play hard’ hypothesis.

Fig. 1. Relationship between Attraction to Accomplishment and

Attraction to Leisure for undergraduate student survey

participants (n=1396, partial correlation coefficient = 0.388, P<0.001).

In other words, our main prediction was that our index of attraction to accomplishment /fame would be strongly correlated with our index of attraction to leisure. And that’s exactly what we found (Fig. 1). The 'work hard – play hard' association, therefore, is clearly not just a cliche, nor is it mythical or ideological; it actually displays as a particular pattern of co-variation in priorities / preferences / personalities — at least for our sample of university undergraduate students.

We find these results interesting to interpret from an evolutionary perspective — i.e. to ask: do 'working hard' and 'playing hard' represent deeply ingrained motivations (conscious or unconscious), informed at least partially by genetic inheritance resulting from selection in the ancestral past?  We suggest that they may tend to occur together because they represent components of innate human drives (discussed in recent posts on MusingsOne.com) that evolved to alleviate the same uniquely human limitation on reproductive success: self-impermanence anxiety associated with mortality salience. Specifically, attraction to accomplishment can be regarded as a component of 'Legacy Drive', i.e. motivation to engage in goals that instill a delusional sense of being able to leave something of oneself — an 'extension-of-self' — for the future, as a perception of death transcendence. Similarly, attraction to play is a manifestation of ‘Leisure Drive’, also delivering self-impermanence anxiety buffers, but of a different sort — involving ‘escape-from-self’, as distractions, deployed through pleasurable free-time indulgences. [Note how conspicuous elements of both drives are represented in the manifesto — at left — for a fulfilling life, from genuinehealth.com.]     

But why the variation in our data?  In other words, what accounts for participants who declared relatively low attractions to both work (accomplishment/fame) and play? The answer may be found in recognizing (as argued in my earlier post) that legacy delusions can be associated with not just accomplishment, but also (or instead) with religion and /or parenthood, and each of these may or may not have any particular correlation with attraction to leisure.  Other analyses (not shown here) suggest that our data include representation of two distinct personality types, equally equipped with adaptive self-impermanence anxiety buffers, but presenting very different psychologies:  a 'religious, family-oriented' type, and a 'secular go-getter'; the 'work hard – play hard' type.       

References


Brotherhood, W. (2011). Nashotah Scholiast, Volume 2, Issues 1-10. (reproduction 1923). Nabu Press (BiblioBazzar), New York: Barnes & Noble.

The 'Big Four' Human Drives

In previous posts, I described how Leisure Drive and Legacy Drive should be considered as fundamental motivational domains for a renovation of Maslow’s (1943) ‘pyramid of needs’.
 

The ‘four-drives’ model for additional renovation of the pyramid of human needs,

 building on the explicitly Darwinian framework incorporated by Kenrick et al. 

(2010). Needs are represented here within four fundamental human 'drives’, 
representing products of selection for distinct domains of human motivations 
that were essential — collectively as an integrated set, it is argued — for 
effecting gene transmission success in ancestors. The latter — the overarching 
evolutionary ‘goal’/consequence — thus occupies the apex position.

As in the Kenrick et al. (2010) renovation, the four-drives pyramid also assumes a developmental but integrative hierarchy, and this is signified by the arrow within the pyramid connecting across all levels. In other words, for the same reasons outlined by Kenrick et al. (2010), and echoing Maslow (1943), higher order goals/drives are generally more active at later developmental stages / ages, and are generally less likely to be satisfied if lower order needs are unmet. Lower level drives, however, can be activated at any stage (i.e. they are not replaced by higher level drives), and once developed, the activation of a drive, or ‘goal system’, will usually be triggered when relevant environmental cues are salient (Kenrick et al. 2010). Becker and Kenrick (2014) elaborate:

“Certain stimuli elicit stronger reactions than others, because they have more significant and/or consistent consequences in the ancestral (or developmental) past. Cognitive systems have thus evolved (or are biologically prepared to learn) a vigilance for stimuli relevant to fundamental goals. Neither the stimuli nor the goals exist in isolation; the psychological system has coevolved with features of the ecology” (p. 137).

This speaks to the appealing notion of different ‘subselves’ (Martindale 1980, Becker & Kenrick 2014), defined by domain-level ‘pyramid’ goals, activated by environmental cues [and underlying a central theme within two recent popular books from Kenrick (Kenrick 2011, Kenrick & Griskevicius 2013)]. Accordingly, we might expect activation of the ‘Legacy-Drive-subself’ versus the ‘Leisure-Drive-subself’ to be contingent on local ecology / culture. One recent study of responses to mortality salience provides an intriguing example of this: European Americans tended to choose responses that focused on achieving symbolic immortality (legacy), while East Asians generally chose responses aimed at engaging in and enjoying life (leisure) (Ma-Kellams and Blascovich 2012)].

The arrowhead in the human needs pyramid, ‘collecting’ the impact of all of the drives, resides in the pyramid apex, representing the ultimate but imperceptible evolutionary ‘goal’ — copying and transmission success for one’s resident genes — subserved by the cognitive goals/drives of one’s conscious (and/or subconscious) mind. And most importantly, regardless of rudimental need fulfillments from deployment of lower drives, the ultimate evolutionary goal remains unattained if there is no sex/mating, and may also be missed (even with sex/mating) if parenting is neglected — although there may be some effective compensation (inclusive fitness) if there is kin-helping.

As in the Kenrick et al. (2010) model, certain specific motivations in the four-drives pyramid may be deployed in solving problems across domains. For example, attraction to religion / spiritualism / mysticism, career achievements, and showing kindness to others, all represent not just ventures for Legacy Drive; they also feel good (satisfying Leisure Drive), they garner resources and/or may earn favor within one’s social group (thus reaping advantage for Survival Drive), and a reputation of success in these pursuits can also be attractive to potential mates (addressing Sexual/Familial Drives). The simple joy from wonder and discovery also feels good at any age, and at the same time can earn acclaim within one’s social group. Accumulation of wealth of course ensures survival, but it also earns status (legacy), buys toys and conspicuous consumption (leisure), and attracts romance (sex). Particular sources of pleasure, providing the self-impermanence anxiety buffers of Leisure Drive, therefore, cut across multiple levels, e.g. involving

physiological needs (eating), but also mating needs (sexual arousal).  Similarly, attraction to parenthood (and grand-parenthood) — an option for delusional legacy through meme uploading to impressionable offspring (and grand-offspring) minds — may also be triggered by Leisure Drive. In other words, intrinsic pleasure rewards can be evoked from the sense of attachment security and self-worth connected with feelings of admiration and acceptance by others that is normally associated with close family relations (and evoked also by intimate relations) (e.g. see Shaver & Mikulincer 2012b, Yaakobi et al. 2014, Nelson et al. 2014).

In many cases then, there is likely to be a blurred distinction, or even a blending, in the deployment of Legacy and Leisure Drives. Human achievements and triumphs define the history of cultural evolution, in large part because they generously rewarded the reproductive success of ancestors. It should be no surprise, therefore, that we are routinely more than content, instinctively so (through evolutionary bequeathal), to endure the striving and struggling needed to reach our individually prescribed goals and achievements — even finding pleasure from the toil itself (sensu Camus’ (1942) depiction of Sisyphus; “The struggle itself … is enough to fill a man’s heart. One must imagine Sisyphus happy”).

Accordingly, distractions of leisure and delusions of legacy may commonly be deployed at the same time in making meaning /happiness for one’s life, all while remaining largely (and safely) incognizant of the fact that time annihilates all that we do.

An example of this blend, it seems, can be found in recent pro-natalist movements that involve attraction to large family size (typically supported by wealth, and combined often, but not in all cases, with religion) (Kaufman 2010, Rowthorn 2011, Caplan 2012). It is interesting to consider whether this represents a distinct motivational ‘sub-domain’ that has perhaps never (or only locally or occasionally) had opportunity, through evolutionary bequeathal, to be conspicuous within human populations — ‘parenting drive’ (Aarssen 2007). This is not the same thing as attraction to legacy through parenthood, or to pleasurable rewards that may be triggered by it (as discussed above). ‘Parenting drive’ here is defined as attraction to legacy through offspring, but one that is heavily layered/infused with intrinsic attraction to a particular kind of pleasure reward at the same time — triggered specifically (odd as it may seem to some) by the hard work of parenting. [Again, there can be a kind of pleasure (a distracting leisure) in purposeful toil and routine (Baumeister et al. 2013)].  And the hard work of parenting is available in greater abundance, of course, with increasing family size (Angeles 2010, Nelson et al. 2013).

Important to note here is that weak parenting drive — despite it’s obvious disadvantage for evolutionary fitness — probably never had widespread opportunity to be strongly disfavoured by natural selection. Historically, many or most women were essentially forced, by patriarchal subjugation and/or religious imperatives, to bear offspring (often many) regardless of whether they had any intrinsic desire to be hard-working mothers (and presumably, often they didn’t). But women now, more than ever, are in control over their own fertility, and their empowerment for this and other basic human rights continues to grow rapidly on a global scale.  And choosing to be ‘childfree’

— as women are now increasingly free to do — means zero gene transmission through direct lineage. Accordingly, selection against weak parenting drive may soon be ramping up (Aarssen 2007). If so, we might ask whether this selection could, within say a generation or two, spell an abrupt end to the now popular childfree culture that accounts in part for the population implosion (below-replacement fertility) that has surfaced in many developed countries in recent years (Aarssen and Altman 2012).

Being fooled by the soothing delusions of ‘post-self’ legacy, and distracted by the lure of pleasurable, ‘outside-of-self’ leisure — and hence also their inducements by mortality awareness and anxiety — all turn out then to be in the best interests of resident genes. And these interests are served only if being fooled and distracted can be sufficiently maintained

until reproductive maturity is reached, and thus long enough to effect potential for successful gene transmission to descendants. As age advances beyond reproductive maturity, however, one may become less easily fooled and distracted. Legacy Drive, it seems then, presents as a kind of revolt against self-impermanence, with perhaps (as an empirical prediction) greater activation expected prior to mid-life — whereas Leisure Drive may serve as more of a therapeutic reconciliation, especially perhaps in later life, when one may be more likely to ‘come to terms’ with the inevitability of self-impermanence. Propensity for self-deception then equips us with more than just skill for deceiving others (Trivers 2011); it protects us from knowing ourselves too much for our own good, or more precisely, for the sake of our gene transmission success.


Male displays of accomplishment / fame (in seeking legacy), and displays of artistic and athletic skills (for acquiring and enjoying leisure) can also, in a different sense, be in the best interests of resident genes: as ‘fitness signals’ in advertising mate quality (Miller 2000, 2009, Saad 2007). Attractiveness of a potential mate in this sense is typically interpreted to be correlated with his prospects (through genetic bequeathal) for resourcefulness (including through creativity) or for providing protection — thus addressing Survival needs for oneself and one’s offspring. And as a product of evolution, it is correlated then with his prospects for passing on these adaptive traits to male offspring. An interesting (and unexplored) extension here is to ask whether these displays are attractive in part because they also signal a potential mate who is well-equipped in deploying delusions for ‘extension of self’

and distractions for ‘escape from self’, thus representing a good prospect as a positive, uplifting companion, and for helping to raise offspring that are similarly well-equipped (through genetic bequeathal) with the Legacy and Leisure Drives needed to keep self-impermanence anxiety and other inevitable human disquietudes at bay. Of course, in none of the above does the adoring female need to be aware that her attraction to the potential mate has been informed by genetic inheritance, or that its consequence is likely to effect her own gene transmission success.

For a self-conscious species with a theory of mind, that can foresee its own death and feel anxiety because of it, Legacy Drive and Leisure Drive, I suggest, are critical for gene transmission success. Legacy Drive serves an intrinsic domain-general need: to be at least periodically fooled into thinking that, despite knowledge of a mortal body, one’s mind (or manifestations of it) can transcend death. In an odd twist of irony then, the fear of failed legacy turns out to be an adaptation, rooted in delusional perceptions of post-self, symbolic immortality through offspring. It may commonly manifest as a cost or trade-off of consciousness, but normally — in the ‘antagonistic pleiotropy’ sense (Williams 1957) — only in the advancing, ‘wiser’ years of older age. In other words, feeling mortality anxiety acutely in later life necessarily imposes a decreasing penalty on evolutionary fitness, because normally by this time (at least for most of our ancestors), gene copies have

already been transmitted to the next generation. And so, while these distractions and delusions may persist beyond middle age in defining psychological needs (e.g. Tinsley and Eldridge 1995, Iwasaki 2008), their effectiveness becomes much less (or un-) important for gene transmission success (especially for post-menopausal, hence infertile, women) — although these needs may serve to ramp up attraction to grandparenting (with attendant rewards for gene transmission success). In addition, it is worth noting that only with recent science and technology have humans become routinely capable of achieving average life expectancies as high as 80 years.

Importantly, however, when the wisdom of age makes us not so easily deluded, Leisure Drive can still ‘come to the rescue’ (if one submits to it) by serving another intrinsic domain-general need: to be at least periodically distracted from the uniquely human

agonizing uncertainty/suspicion — and for those so persuaded, from the conclusion of Darwinism — that we cannot transcend death, that there is no symbolic immortality or everlasting ‘post-self’, that legacy of the self is just a beautiful dream. Leisure Drive then protects us from learning, understanding, believing, and/or remembering that the only ‘unifying purpose’ or ‘intelligent design’ of life (if it can be called these) lies in the laws of physics and mathematics that shape the emergent properties of chemical, structural, and behavioral phenotypes. As Francis Crick put it: “You, your joys and sorrows, your memories and your ambitions, your sense of personal identity and your free-will, are in fact no more than the behavior of a vast assembly of nerve-cells and their attendant molecules” (Crick 1994, p. 3). Humans, and apparently no other animals, have evolved not just the cognitive capacity to arrive at this diagnosis, but also a desperate need to purge it from consciousness.

This above tutelage from Crick then does not imply — as interpreted by Mary Midgley — that the self does not exist; it does not deny that humans are “… creatures with needs, tendencies and directions of their own” (Midgley 2014, p.62). It just says that the self, the ‘inner life’, is not what our evolved hope is for it to be — an evolved hope that nevertheless served well our ancestors’ genes. Importantly, evolution by natural selection tracks fitness, not happiness. As Nettle (2005) put it: “The idea of happiness has done its job if it has kept us trying. In other words, evolution hasn’t set us up for the attainment of happiness, merely its pursuit. ... We don’t necessarily learn from experience that this is a trick, because we are not necessarily designed to do so” (p. 68). In fact, as argued here, we are designed to be tricked, because this ‘blind’ pursuit, all by itself, has served well in propelling ancestral gene copies into future generations.

Components of Survival Drive and Sexual/Familial Drives and their evolutionary roots, are supported by a large body of literature, comprehensively reviewed by Kenrick et al. (2010) and others. Legacy Drive and Leisure Drive, however, represent mostly hypotheses yet to be tested with more research. I predict that future studies will support the interpretation that these drives served well our ancestors’ genes by palliating the potentially incapacitating ‘curse’ of consciousness — at least over the several years of reproductive immaturity

required prior to successful mating and parenting. In this way, Legacy and Leisure Drives served to prevent the uniquely human fitness benefits of self- and time-awareness, and theory of mind from being compromised by self-impermanence anxiety. Recent advances in the field of ‘terror management’ theory — showing deployment of various mortality anxiety buffers, manifesting as behaviours that bolster self-steem/ meaning/ purpose/ redemption/ value for one’s life, and connected with a sense of membership within (and validation for) larger-than-self cultural worldviews (Greenberg et al. 2004, Vess et al. 2009, Pyszczynski et al. 2010, Solomon et al. 2010, Vail et al. 2010) — already point to the plausibility of the evolutionary interpretations argued here.

The four fundamental drives model proposed here, I suggest, has potential for informing both theory and application for metrics of ‘flourishing’ and subjective well-being in positive psychology (Land et al 2012, Wong 2012, Freire 2013, Leontiev 2013, Batthyany & Russo-Netzer 2014, Tay et al.2014). Even more generally, I suggest, it lays groundwork for a novel view of the evolutionary roots of human nature and social life, and hence the rich and puzzling variety of cultural norms, celebrated across the globe, and underlining the scholarly interpretations of human history.

References

Aarssen, L W. (2007). Some bold evolutionary predictions for the future of mating in humans. Oikos, 116, 1768-78.

Aarssen, L. W., & Altman, T. (2012). Fertility preference inversely related to ‘legacy drive’ in women, but not men: Interpreting the evolutionary roots, and future, of the ‘childfree’ culture. The Open Behavioral Science Journal, 6, 37-43.

Angeles L. (2010). Children and life satisfaction. Journal of Happiness Studies, 11, 523-538.

Batthyany, A., & Russo-Netzer, P. (Eds.) (2014). Meaning in Positive and Existential Psychology. New York: Springer.

Baumeister, R. F., Vohs, K. D., Aaker, J. L., & Garbinsky, E. N. (2013). Some key differences between a happy life and a meaningful life. The Journal of Positive Psychology, 8, 505–516.

Becker, D. V., & Kenrick, D. T. (2014). Selfish goals serve more fundamental social and biological goals. Behavioral and Brain Science, 37, 137-138 doi:10.1017/S0140525X13001957.

Camus, A. ([1942] 1955). The Myth of Sisyphus, and Other Essays (O’Brien J, trans). New York: Knopf.

Caplan, B. (2012). Selfish Reasons to Have More Kids: Why Being a Great Parent is Less Work and More Fun Than You Think. New York: Basic Books.

Crick, F. (1994). The Astonishing Hypothesis: The Scientific Search For The Soul. New York: Touchstone.

Freire, T. (2013). Positive Leisure Science: From Subjective Experience to Social Contexts. Dordrecht: Springer.

Greenberg, J., Koole, S. L., & Pyszczynski, T. (Eds.). (2004). Handbook of Experimental Existential Psychology. New York: Guilford Press.

Iwasaki, Y. (2008). Pathways to meaning-making through leisure-like pursuits in global contexts. Journal of Leisure Research, 40, 231-249.

Kaufmann, E. (2010). Shall the Religious Inherit the Earth? Demography and Politics in the Twenty-First Century. London: ProfileBooks.

Kenrick, D. T. (2011). Sex, Murder, and the Meaning of Life: A Psychologist Investigates How Evolution, Cognition, and Complexity are Revolutionizing our View of Human Nature. New York: Basic Books.

Kenrick, D. T, & Griskevicius, V. (2013). The Rational Animal: How Evolution Made Us Smarter Than We Think. New York: Basic Books.

Kenrick, D. T., Griskevicius, V., Neuberg,, S. L., & Schaller, M. (2010). Renovating the pyramid of needs: contemporary extensions built upon ancient foundations. Perspectives on Psychological Science, 5, 292-314.

Land, K. C., Michalos, A. C. & Sirgy, M. J (Eds.) (2012). Handbook of Social Indicators and Quality of Life Research. New York: Springer.

Leontiev, D. A. (2013) Positive psychology in search for meaning: An introduction. The Journal of Positive Psychology 8, , 457–458.

Ma-Kellams, C., & Blascovich, J. (2012). Enjoying life in the face of death: East–west differences in responses to mortality salience. Journal of Personality and Social Psychology, 103, 773-786.

Martindale, C. (1980). Subselves: The internal representation of situational and personal dispositions. In L. Wheeler (ed.), Review of personality and social psychology, pp. 193–218. Beverly Hills, Ca: Sage.

Maslow, A.H. (1943). A theory of human motivation. Psychological Review, 50, 370–396.

Midgley, M. (2014). Are You An Illusion? Durham: Acumen.

Miller, G. (2000). The Mating Mind. New York: Random House.

Miller, G. (2009). Spent: Sex, Evolution and Consumer Behaviour. New York: Viking.

Nelson, S. K., Kushlev, K., English, T., Dunn, E. W., & Lyubomirsky, S. (2013), In defense of parenthood: Children are associated with more joy than misery. Psychological Science, 24, 3–10.

Nelson, S. K., Kushlev, K., & Lyubomirsky, S. (2014). The pains and pleasures of parenting: when, why, and how is parenthood associated with more or less well-being? Psychological Bulletin, 140, 846–895

Nettle, D. (2005). Happiness: The Science Behind Your Smile. Oxford: Oxford University Press.

Pyszczynski, T., Greenberg, J., Koole, S., & Solomon, S. (2010). Experimental existential psychology: Coping with the facts of life. In Fiske, S., Gilbert, D. & Lindzey, G. (Eds.), Handbook of Social Psychology. London: John Wiley and Sons.

Rowthorn, R, (2011) Religion, fertility and genes: a dual inheritance model. Proceedings of the Royal Society, B, 278, 2519–2527.

Saad, G. (2007). The Evolutionary Bases of Consumption. Mahwah, NJ: Lawrence Erlbaum.

Shaver, P. R., & Mikulincer, M. (Eds.) (2012a). Meaning, Mortality, and choice: The Social Psychology of Existential Concerns. Washington, DC: American Psychological Association.

Solomon, S., Greenberg, J., Pyszczynski, T. Cohen, F., & Ogilvie, D.M. (2010). Teach these souls to fly: Supernatural as human adaptation. In M. Schaller, A. Norenzayan, S. J. Heine, T. Yamagishi, & T. Kameda (Eds.). Evolution, Culture and the Human Mind (pp. 99-118). New York: Psychology Press.

Tay, L., Chan, D, & Diener, E. (2014). The metrics of societal happiness. Social Indicators Research, 117, 577-600.

Tinsley, H. E. A., & Eldredge, B. D. (1995). Psychological benefits of leisure participation: A taxonomy based on their need-gratifying properties. Journal of Counselling Psychology, 42, 123-132.

Trivers, R. (2011). The Folly of Fools: The Logic of Deceit and Self-deception in Human Life. New York: Basic Books.

Vail, K. E., Rothschild, Z. K., Weise, D. R., Solomon, S., Pyszczynski, T., & Greenberg, J. (2010). A terror management analysis of the psychological functions of religion. Personality and Social Psychology Review, 14, 84–94.

Vess, M., Routeldge, C., Landau, M. J, & Arndt, J. (2009). The dynamics of death and meaning: The effects of death-relevant cognitions and personal need for structure on perceptions of meaning in life. Journal of Personality and Social Psychology, 97, 728-744.

Williams, G. (1957). Pleiotrpy, natural selection and the evolution of senescence. Evolution, 11, 398-411.

Wong, P. T. P (Ed.) (2012). The Human Quest for Meaning: Theories, Research, and Applications (2nd edn.). New York: Routledge.

Yaakobi, E., Mikulincer, & Shaver, P. R. (2014). Parenthood as a terror management mechanism: The moderating role of attachment orientations. Personality and Social Psychology Bulletin, 40, 762-774.  

Legacy Drive

In a previous post [ here ], I discussed how easy it is to notice that people everywhere seem to be routinely drawn to opportunities for free-time indulgence in leisure, with magnitudes of variety, scale, and commitment not seen in other animals. I interpret this motivation as instinctual — a deeply ingrained product of natural selection, rewarding our ancestors with reproductive success because it provided them with effective and easily deployed distractions from the uniquely human awareness of — and universal anxiety about — self-impermanence. Here I argue that self-impermanence anxiety buffers can also manifest in a distinctively different sense — as delusions for nevertheless leaving recognition of oneself   for the future: ‘Legacy Drive’ (Aarssen & Altman 2006).  Hence, whereas Leisure Drive facilitates meaning in terms of hedonic wellbeing, as an ‘escape

from self’, Legacy Drive facilitates meaning in terms of eudaimonic wellbeing, as an ‘extension of self’. Their distinction is real and important; recent experimental studies have shown that a satisfying life can be hedonically happy but eudaimonically meaningless, whereas in other cases it can be eudaimonically meaningful but hedonically unhappy (Baumeister et al. 2013, Delle Fave 2013).

Legacy delusions may manifest through at least three distinct ventures for human flourishing, self-referentiality, larger-than-self-identity, after-life transcendence, and/or symbolic immortality: religion, parenthood, and accomplishment. The latter has overshadowed the other two within the cultural evolution of modern times, with historically increasing opportunities — particularly in more developed countries (and especially for women) — for

a wide array of human endeavors that normally draw attention and earn acclaim or favorable reputation. Accomplishment is fueled by attraction to things like financial wealth and consumerism / materialism (e.g. Gountas et al. 2012, Shrum et al. 2013), successful business / institutional affiliations (e.g. Fox et al. 2010), philanthropy (e.g. Wade-Benzoni et al. 2012), and presumably many others (Maltby 2010): academic awards, competition for trophies / championships, volunteering for community service, showing kindness to others, recognition of virtue or bravery/heroism in a civilian crisis or in war,

and pursuits of rewarding careers that commonly evoke admiration and/or prestige — e.g. in politics, government, law, teaching, social work, medicine, health care, the military, professional sports, research and invention, and the arts (involving literature, acting, film production, musicianship and other artistic displays and creative products) (Aarssen 2010).

A sense of purpose/esteem/recognition might also be evoked by something as simple as praise or promotion from an employer for good work (Barrick et al 2013), providing mentorship for a colleague, taking a stand in championing a ‘cause’ among peers within club memberships or public protest/grassroots movements, commanding respect from family or from rivals, or just earning popularity and admiration from a circle of friends or associates (Greenwood et al. 2013). Celebrity/notoriety can, of course, also be earned from displays of non-conformity, ranging from

harmless projections of ‘cool’, or making a personal ‘statement’of rejection against fads / customs / societal norms (Warren and Campbell 2014), to deplorable extremes of deviant behavior and criminal activity (Parnaby and Sacco 2004).

The key argument here is that these many alternative engagements for a sense of recognition/status, belongingness, pride, and fulfillment of one’s perceived potential are likely to be routinely successful in fooling the mind/self into thinking that it need not be impermanent after all. In other words, the sentient human mind is predisposed (by evolution) to be easily drawn into believing, naively, that it can have a ‘post-self’ by being ‘larger-than-self’ — i.e. through ‘membership’ within a conspicuous cultural world-view, or by residing as a soul/spirit

or as reincarnations throughout eternity (Solomon et al. 2010, Vail et al. 2010, Ellis and Wahab 2013); by attaining symbolic immortality as memes residing in the minds of one’s offspring (Higginson and Aarssen 2011), or as fond remembrances or records of success / status / reputation residing in the minds of one’s contemporaries (e.g. Greenberg et al. 2010, Wojtkowiak & Rutjens 2011, Sligte et al. 2013), with

a potential chain of influence passed on to their descendants in perpetuity; and/or as representations of legacy imbued in artifacts, inscribed on monuments, or stored in the written archives of history (Shneidman 1973, Aarssen 2010, Cave 2012).

Importantly, feeling a sense of meaning/purpose though Legacy Drive is always just a delusion. Consider that today, for every deceased human that has ever existed (save for a miniscule micro-fraction), it is as though s(he) never did. Only genes have legacy (Dawkins 1989), but Legacy Drive has a powerful hold on human nature nonetheless, potentially, it is argued, because of its evolutionary roots in an ancestral attraction to ‘memetic legacy’ through feeling a sense that one can create a lasting ‘carbon-copy’ of self by shaping the minds — the ideas, values, beliefs, ego, self-

image/esteem, personality, and virtue of character — of one’s offspring. This is also mostly a delusion, with parents easily fooled (e.g. see Harris 1998), but the reward nevertheless goes to genes because offspring are the very vehicles of genetic legacy, including importantly, for genes that might inform Legacy and Leisure Drives (Aarssen 2007, 2010). As Barash (2012) put it, “Maybe awareness of mortality isn’t merely a tangential consequence of consciousness but its primary adaptive value, if it has the effect of inducing people to seek yet another way of rebelling against mortality: by reproducing” (p. 301).

Several recent experimental studies of mortality priming have shown that the perception of parenthood can be an effective death-anxiety buffer (Wisman & Goldenberg 2005; Fritsche et al. 2007; Mathews & Sear 2008; Zhou et al. 2008, 2009, Yaakobi et al. 2014). On one level this might be interpreted as a consequence of traditional life history theory, applied broadly to more than just humans; i.e. “…fertility behaviour is likely to be particularly sensitive to mortality levels and patterns, given the key importance of mortality in determining the payoffs to life history decisions such as when to stop growing and reproducing, how to allocate investment between quantity and quality of children, etc. … High and unpredictable mortality regimes are likely to favour an early start to reproduction and high fertility, whereas low and stable mortality is predicted to lead to later and lower fertility” (Mathews & Sear 2008, p. 156).

Alternatively (or in addition), as interpreted here, perceptions of offspring and parenthood provide deep-seated symbolism for immortality. Gene transmission per se of course is not a cognitive human goal (or at least never was prior to Gregor Mendel, less than two centuries ago). But pride in offspring (and also adopted children), forethought/planning for having them, and eager anticipation of their birth (or adoption) and family membership are all (we can reasonably assume) universal and uniquely human emotions and intentions. And they represent obvious manifestations of attraction to legacy, bolstering a delusional confidence in being able to leave extensions of ‘self’ (or at least the self that one aspires to, or at one time did) that might transcend death. As Schaller et al. (2010) recognize, an “…affective reward comes as we make progress toward the underlying evolutionary objective — when

… the child scampers off the school bus and proudly produces a remarkable report card.” (p. 336). Importantly here, it is the parent who especially feels pride (e.g. see Brooks 2013; Feiler 2013), and this is more than just a symptom of parental care instinct shared with other animals; it is a principal phenotype of the universal and uniquely human drive to leave something significant of oneself — a post-self — for the future.



In a future post, I will consider how Legacy Drive and Leisure Drive are likely to be deployed often in a blended fashion, triggered by developmental and environmental cues, and integrated with other goal systems, all shaped in part by genes inherited from ancestors — genes informing a framework that ensured their own copying and transmission success to future generations: a ‘pyramid of human needs’.

References

Aarssen, L W. (2007). Some bold evolutionary predictions for the future of mating in humans. Oikos, 116, 1768-78.

Aarssen, L. W. (2010). Darwinism and meaning. Biological Theory, 5, 296–311.

Aarssen, L. W., & Altman, S. T. (2006). Explaining below-replacement fertility and increasing childlessness in wealthy countries: Legacy drive and the ‘transmission competition’ hypothesis. Evolutionary Psychology, 4, 290-302.

Barash, D. P. (2012). Homo Mysterious: Evolutionary Puzzles of Human Nature. New York: Oxford University Press.

Barrick, M. R., Mount, M. K., & Li, N. (2013). The theory of purposeful work behavior: The role of personality, higher order goals, and job characteristics. Academy of Management Review, 38, 132-153.

Baumeister, R. F., Vohs, K. D., Aaker, J. L., & Garbinsky, E. N. (2013). Some key differences between a happy life and a meaningful life. The Journal of Positive Psychology, 8, 505–516.

Brooks, R. (2013). My child has achieved more than your child. http://www.drrobertbrooks.com/monthly_articles/1305.

Cave, S. (2012). Immortality: the quest to live forever and how it drives civilization. New York: Crown Publishers.

Dawkins, R. (1989). The Selfish Gene, rev. ed. Oxford: Oxford University Press.

Delle Fave, A., Brdar, I., Wissing, M. P., & Vella-Brodrick, D. A. (2013). Sources and motives for personal meaning in adulthood. The Journal of Positive Psychology, 8, 517–529.

Ellis, L., & Wahab, E. A. (2013). Religiosity and fear of death: A theory-oriented review of the empirical literature. Review of Religious Research, 55, 149-189.

Feiler, B. (2013) A truce in the bragging wars. New York Times, published February 1, 2013, http://www.nytimes.com/2013/02/03/fashion/time-for-a-truce-in-the-bragging-wars.html?pagewanted=all&_r=0

Fox, M., Plunkett Tost, L., & Wade-Benzoni, K. A. (2010). The legacy motive: A catalyst for sustainable decision making in organizations. Business Ethics Quarterly, 20, 153-185.

Fritsche, I., Jonas, E., Fischer, P., Koranyi, N., Berger, N., & Fleischmann, B. (2007). Mortality salience and the desire for offspring. Journal of Experimental Social Psychology, 43, 753–762.

Gountas, J., Gountas, S., Reeves, R. A., & Moran, L. (2012). Desire for fame: scale development and association with personal goals and aspirations. Psychology and Marketing, 29, 680 – 689.

Greenberg, J., Kosloff, S., Solomon, S., Cohen, F., & Landau, M. (2010). Toward understanding the fame game: The effect of mortality salience on the appeal of fame. Self and Identity, 9, 1–18.

Greenwood, D., Long, C.R., & Dal Cin, S. (2013). Fame and the social self: The need to belong, narcissism, and relatedness predict the appeal of fame. Personality and Individual Differences, 55, 490-495.

Harris, J. R. (1998). The Nurture Assumption: Why Children Turn Out the Way They Do. New York: Simon & Schuster.

Higginson, M. T., & Aarssen, L. W. (2011). Gender bias in offspring preference: sons still a higher priority, but only in men — women prefer daughters. Open Anthropology Journal, 4, 60-65.

Maltby, J. (2010). An interest in fame: confirming the measurement and empirical conceptualization of fame interest. British Journal of Psychology, 101, 411-432.

Mathews, P., & Sear, R. (2008). Life after death: An investigation into how mortality perceptions influence fertility preferences using evidence from an internet based experiment. Journal of Evolutionary Psychology, 6, 155–172.

Parnaby, P. K., & Sacco, V. F. (2004). Fame and strain: the contributions of mertonian deviance theory to an understanding of the relationship between celebrity and deviant behavior.

Schaller, M., Neuberg, S.L., Griskevicius, V., & Kenrick, D.T. (2010). Pyramid power: A reply to commentaries. Perspectives on Psychological Science, 5, 335–337.

Shneidman, E. S. (1973). Deaths of Man. Oxford: Quadrangle/New York Times Book Co.

Shrum, L. J., Wong, N., Arif, F., Chugani, S. K., Gunz, A., Lowrey, T. M., Nairn, A., Pandelaere, M., Ross, S. M., Ruvio, A., Scott, K., & Sundie, J. (2013). Reconceptualizing materialism as identity goal pursuits: Functions, processes, and consequences. Journal of Business Research, 66, 1179-1185.

Sligte, D.J., Nijstad, B.A., & De Dreu, C. K .W. (2013). Leaving a legacy neutralizes negative effects of death anxiety on creativity. Personality and Social Psychology Bulletin, 39, 1152-1163.

Solomon, S., Greenberg, J., Pyszczynski, T. Cohen, F., & Ogilvie, D.M. (2010). Teach these souls to fly: Supernatural as human adaptation. In M. Schaller, A. Norenzayan, S. J. Heine, T. Yamagishi, & T. Kameda (Eds.). Evolution, Culture and the Human Mind (pp. 99-118). New York: Psychology Press.

Vail, K. E., Rothschild, Z. K., Weise, D. R., Solomon, S., Pyszczynski, T., & Greenberg, J. (2010). A terror management analysis of the psychological functions of religion. Personality and Social Psychology Review, 14, 84–94.

Wade-Benzoni, K. A., Plunkett Tost, L., Hernandez, M., & Larrick, R. P. (2012). It’s only a matter of time: death, legacies, and intergenerational decisions. Psychological Science, 23, 704-709.

Warren, C., & Campbell, M. C. 2014. What makes things Cool? How autonomy influences perceived coolness. Journal of Consumer Research http://www.jstor.org/stable/10.1086/676680.

Wisman, A., & Goldenberg, J. (2005). From grave to the cradle: Evidence that mortality salience engenders a desire for offspring. Journal of Personality and Social Psychology, 89, 46–61.

Wojtkowiak, J., & Rutjens, B. T. (2011). The postself and terror management theory: Reflecting on after death identity buffers existential threat. The International Journal for the Psychology of Religion, 21, 137-144.

Yaakobi, E., Mikulincer, & Shaver, P. R. (2014). Parenthood as a terror management mechanism: The moderating role of attachment orientations. Personality and Social Psychology Bulletin, 40, 762-774.

Zhou, X., Lei, Q., Marley, S. C., & Chen, J. (2009). Existential function of babies: Babies as a buffer of death-related anxiety. Asian Journal of Social Psychology, 12, 40–46.

Zhou, X., Liu, J., Chen, C., & Yu, Z. (2008). Do children transcend death? An examination of the terror management function of offspring. Scandinavian Journal of Psychology, 49, 413–418.

Leisure Drive

Leisure is an integral component of the human pursuit of happiness and wellbeing (Newman et al. 2014), with roots in Epicureanism, the ‘pleasure principle’ of Freudian psychology,

and the ‘nirvana’ of Buddhism. It has long been an institution unto itself, with whole journals dedicated to its study in sociology and social psychology (Tinsley & Tinsley 1986, Crawford et al. 1991, Iwasaki 2008, Kleiber et al. 2011, Brajsa-Zgnanec et al. 2011, Barnett 2013, Freire 2013). Few (if any) other animals can be said to engage in leisure. But if they do, the scale, complexity, and time / energy / material allocation commitments involved all pale in comparison to humans.  

Attraction to leisure, or ‘Leisure Drive’, was introduced in a previous post [ here ] about pyramids of human motivation. Here, I develop greater definition of Leisure Drive — as a deeply ingrained adaptive cognitive domain, defining a fundamental need to dispel negative mood, deployed mainly as a reprieve from the cost of consciousness: self-impermanence anxiety (Aarssen 2007, 2010). Leisure Drive is satisfied by hard-wired pleasure perceptions associated with various forms of sensory gratification, relaxation, cognitive/intellectual stimuli and enlightenment, social affiliations, physical fitness / exercise involving recreational athletics/team sports, and various emotions involving intimacy, family relations, companionship, belongingness, etc. Initially, pleasure-based motivations to seek

and engage with these experiences — modulated by prescribed ‘cocktails’ of hormones and neurotransmitters — would have evolved because of their particular rudimental or proximate effects on evolutionary fitness — i.e. in promoting survival (e.g. resting, eating nutritious foods, cultivating social alliances, learning and understanding through curiosity and imagination, using play and games to practice social skills and rehearse for war), and in promoting reproduction (e.g. sexual arousal, courtship, parental care) and welfare for one’s collateral lineage (e.g. affection for kin).

Importantly however, as posited here, natural selection was not finished. Attraction to the above activities and pursuits was honed further by evolution, purely for the sake of their sheer intrinsic enjoyment. In other words, these ancient, innately endowed pleasure modules became not just anticipated within daily routines, but also intentionally planned and prioritized for free-time indulgence — i.e. directly functional as a domain-general need in its own right. As ventures of leisure, they served (and continue today in serving, probably uniquely for humans) a primary role in propelling ancestral genes into future generations: by providing easily deployed distractions (buffers) from the inevitable

anxieties of life, including the most elemental and most debilitating of all — awareness of self-impermanence, and its associated fear of failed legacy. ‘Forgetting of self’ and ‘decreased awareness of time’ are regarded as key cognitive attributes of leisure experiences (Tinsley and Tinsley 1986), to which we can thus add — in addition to those above — mind-altering escapism in things like stories, videos, comedy, carnivals, festivals, thrill seeking, shopping, toys, hobbies, vacations, aesthetics, music, nostalgia, yoga, meditation, secular spiritualism, sleep, mood medication, and substance-induced intoxication and hallucination. Opportunities for these various indulgences have, of course, grown exponentially through cultural evolution ever since the dawn of Neolithic agriculture.

By distracting the mind with these many options for triggering pleasure / bliss / ecstasy / nirvana, Leisure Drive then enables a forgetting of self, and hence a denial of death (Becker 1973). It delivers an escape from time and from the terror of history (e.g. see Ruiz 2011) by palliating the many hardships, sufferings, and absurdities that (for most of ancestral as well as contemporary humanity) were/are routine consequences of just being alive (Benatar 2006). These distractions (occurring with sufficient magnitude, duration and frequency), it can be argued, thus served our ancestors genes by preventing self-impermanence salience and other anxieties from compromising the successful deployment of Sexual/Familial Drives. After all, for many people, ‘escape from self’ also has a darker side, as motivation for suicide (Baumeister 1990). Recent studies have shown that when the mind is allowed to wander disengaged, essentially unoccupied by fulfilling motivations and unprotected by ‘present-moment’ mindfulness, it is usually an anxious,

unhappy mind (Killingsworth and Gilbert 2010, Wilson et al. 2014). Leisure Drive then functions — probably subconsciously much of the time — to help ensure that such anxieties are kept largely in check by more edifying ventures for escape to ‘outside-of-self’, at least until reproductive age is attained.


Accordingly, a sense of ‘meaning’ in life is evoked here — and ironically, is actually defined — in terms of being sufficiently distracted (through pleasure) from the nagging worry (echoing Camus 1942) that there possibly/probably isn’t any meaning. Pre-occupation, activated by Leisure Drive, effectively diverts the sentient mind from its impulsive

tendency to arrive at (and to relentlessly revisit) an unsettling deduction: that notions of self-transcendence or of a grand cosmic purpose for one’s life are / may be nothing but imaginary mental constructs. For many then, a life may be meaningful by simply filling it adequately with things that feel good, without knowingly harming others of course — because, for most people today (thanks in part to genetic bequeathal), pleasure is normally evoked by helping (not harming) others, and by showing kindness (Rudd et al. 2014) and cooperation (Bowles and Gintis 2011) with others.


All of this, however, begs the question: why is the above deduction, for most humans, so routinely salient and at the same time so immediately unsettling in the first place? One hypothesis, argued in a later post, is that this whole syndrome of mental anxiety generated a uniquely human goal system that played a critical role in driving ancestors to reproduce. All animals have Sex Drive, but only humans have Legacy Drive.

References

Aarssen, L W. (2007). Some bold evolutionary predictions for the future of mating in humans. Oikos, 116, 1768-78.

Aarssen, L. W. (2010). Darwinism and meaning. Biological Theory, 5, 296–311.

Barnett, L. (2013). What people want from their leisure: The contributions of personality facets in differentially predicting desired leisure outcomes. Journal of Leisure Research, 45, 150-191.

Baumeister, R. F. 1990. Suicide as escape from self. Psychological Review, 97, 90-113.

Baumeister, R. F., Vohs, K. D., Aaker, J. L., & Garbinsky, E. N. (2013). Some key differences between a happy life and a meaningful life. The Journal of Positive Psychology, 8, 505–516.

Becker, E. (1973). The Denial of Death. New York: Simon and Schuster.

Benatar, D. (2006). Better Never to Have Been: The Harm of Coming into Existence. New York: Oxford University Press.

Bowles, S., & Gintis, H. (2011). A cooperative species: human reciprocity and its evolution. Princeton: Princeton University Press

Brajsa-Zganec, A., Merkas, M., & Sverko, I. (2011). Quality of life and leisure activities: How do leisure activities contribute to subjective well-being. Social Indicators Research, 102, 81-91.

Camus, A. ([1942] 1955). The Myth of Sisyphus, and Other Essays (O’Brien J, trans). New York: Knopf.

Crawford, D. W., Jackson, E. L., & Godbey, G. (1991). A hierarchical model of leisure constraints. Leisure Sciences, 13, 309-320.

Freire, T. (2013). Positive Leisure Science: From Subjective Experience to Social Contexts. Dordrecht: Springer.

Iwasaki, Y. (2008). Pathways to meaning-making through leisure-like pursuits in global contexts. Journal of Leisure Research, 40, 231-249.

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