Slow Life History Strategy Research Articles

Reproductive Strategy and Sexual Conflict Slow Life History Strategy Inihibts Negative Androcentrism

Recent findings indicate that a slow Life History (LH) strategy factor is associated with increased levels of Executive Functioning (EF), increased emotional intelligence, decreased levels of sexually coercive behaviors, and decreased levels of negative ethnocentrism. Based on these findings, as well as the generative theory, we predicted that slow LH strategy should inhibit negative androcentrism (bias against women). A sample of undergraduates responded to a battery of questionnaires measuring various facets of their LH Strategy, (e.g., sociosexual orientation, mating effort, mate-value, psychopathy, executive functioning, and emotional intelligence) and various convergent measures of Negative Androcentrism. A structural model that the data fit well indicated a latent protective LH strategy trait predicted decreased negative androcentrism. This trait fully mediated the relationship between participant biological sex and androcentrism. We suggest that slow LH strategy may inhibit negative attitudes toward women because of relatively decreased intrasexual competition and intersexual conflict among slow LH strategists.

Reproductive Strategy and Sexual Conflict Slow Life History Strategy Inihibts Negative Androcentrism

Recent findings indicate that a slow Life History (LH) strategy factor is associated with increased levels of Executive Functioning (EF), increased emotional intelligence, decreased levels of sexually coercive behaviors, and decreased levels of negative ethnocentrism. Based on these findings, as well as the generative theory, we predicted that slow LH strategy should inhibit negative androcentrism (bias against women). A sample of undergraduates responded to a battery of questionnaires measuring various facets of their LH Strategy, (e.g., sociosexual orientation, mating effort, mate-value, psychopathy, executive functioning, and emotional intelligence) and various convergent measures of Negative Androcentrism. A structural model that the data fit well indicated a latent protective LH strategy trait predicted decreased negative androcentrism. This trait fully mediated the relationship between participant biological sex and androcentrism. We suggest that slow LH strategy may inhibit negative attitudes toward women because of relatively decreased intrasexual competition and intersexual conflict among slow LH strategists. DOI:10.2458/azu_jmmss_v4i1_gladden

Reproductive Strategy and Sexual Conflict Slow Life History Strategy Inihibts Negative Androcentrism

Recent findings indicate that a slow Life History (LH) strategy factor is associated with increased levels of Executive Functioning (EF), increased emotional intelligence, decreased levels of sexually coercive behaviors, and decreased levels of negative ethnocentrism. Based on these findings, as well as the generative theory, we predicted that slow LH strategy should inhibit negative androcentrism (bias against women). A sample of undergraduates responded to a battery of questionnaires measuring various facets of their LH Strategy, (e.g., sociosexual orientation, mating effort, mate-value, psychopathy, executive functioning, and emotional intelligence) and various convergent measures of Negative Androcentrism. A structural model that the data fit well indicated a latent protective LH strategy trait predicted decreased negative androcentrism. This trait fully mediated the relationship between participant biological sex and androcentrism. We suggest that slow LH strategy may inhibit negative attitudes toward women because of relatively decreased intrasexual competition and intersexual conflict among slow LH strategists. DOI:10.2458/azu_jmmss_v4i1_gladden

‘Slow’ reproductive strategy: A negative predictor of depressive symptomatology

The present study examined the associations between a high‐K (slow) life history strategy and depressive symptomatology. The participants were a sample of 494 male utility workers who underwent psychological evaluations. It was hypothesised that high‐K will correlate negatively with, and will be a negative predictor of, depressive symptomatology. The results confirmed the predictions, showing that high‐K accounts for 15% of the variance in depressive symptomatology after controlling for risk factors for depression such as demographics, prior traumatic experiences, past depression, and recent negative life events. Implications of the results are discussed.

Slow and steady wins the race: Life history, mate value, and mate settling

Life history theory explains how individuals decide to invest their limited resources, which involves several trade-offs. Particularly relevant to the current work, individuals can choose to invest in current or delayed reproduction (a slow life history strategy), which implicates a trade-off between the quantity and the quality of one’s offspring. Choosing to delay reproduction allows for increased self-investment, and previous research has demonstrated that traits requiring self-investment are related to higher mate value. As such, the current study hypothesizes that slow life history strategy will predict high personal mate value and high levels of partner mate-value within heterosexual partnerships. Similarly, those with a slow life history strategy should display fewer tendencies toward mate-settling. The current work employs both subjective and objective measures of mate value within mateships to investigate these hypothesized relationships. As hypothesized, significant positive relationships among life history and mate value were detected, suggesting that a slower life history strategy corresponds to high ratings of mate value for both self and partner. Also, life history strategy is a significant predictor of subjective, objective, and Mate Value Inventory ratings of partner and self. Further implications and potential future works are discussed.

The impact of sex ratio and economic status on local birth rates

Human mating and reproductive behaviour can vary depending on various mechanisms, including the local sex ratio. Previous research shows that as sex ratios become female-biased, women from economically deprived areas are less likely to delay reproductive opportunities to wait for a high-investing mate but instead begin their reproductive careers sooner. Here, we show that the local sex ratio also has an impact on female fertility schedules. At young ages, a female-biased ratio is associated with higher birth rates in the poorest areas, whereas the opposite is true for the richest areas. At older ages, a female-biased ratio is associated with higher birth rates in the richest, but not the poorest areas. These patterns suggest that female-female competition encourages poorer women to adopt a fast life-history strategy and give birth early, and richer women to adopt a slow life-history strategy and delay reproduction.

The impact of stress on the life history strategies of African American adolescents: cognitions, genetic moderation, and the role of discrimination.

The impact of 3 different sources of stress--environmental, familial (e.g., low parental investment), and interpersonal (i.e., racial discrimination)--on the life history strategies (LHS) and associated cognitions of African American adolescents were examined over an 11-year period (5 waves, from age 10.5 to 21.5). Analyses indicated that each one of the sources of stress was associated with faster LHS cognitions (e.g., tolerance of deviance, willingness to engage in risky sex), which, in turn, predicted faster LHS behaviors (e.g., frequent sexual behavior). LHS, then, negatively predicted outcome (resilience) at age 21.5 (i.e., faster LHS → less resilience). In addition, presence of the risk ("sensitivity") alleles of 2 monoamine-regulating genes, the serotonin transporter gene (5HTTLPR) and the dopamine D4 receptor gene (DRD4), moderated the impact of perceived racial discrimination on LHS cognitions: Participants with more risk alleles (higher "sensitivity") reported faster LHS cognitions at age 18 and less resilience at age 21 if they had experienced higher amounts of discrimination and slower LHS and more resilience if they had experienced smaller amounts of discrimination. Implications for LHS theories are discussed.

Influence of life history strategies on sensitivity, population growth and response to climate for sympatric alpine birds

BackgroundThe life history strategy of a species can influence how populations of that species respond to environmental variation. In this study, we used a matrix modeling approach to examine how life history differences among sympatric rock and white-tailed ptarmigan affect the influence of demographic rates on population growth (λ) and the potential response to a changing climate. Rock ptarmigan have a slower life history strategy than white-tailed ptarmigan in the study region with lower annual reproductive effort but higher adult survival.ResultsBased on data from a 5-year field study, deterministic estimates of λ indicated that populations were stable for rock ptarmigan (λ = 1.01), but declining for white-tailed ptarmigan (λ = 0.96). The demographic rates with the highest elasticity for rock ptarmigan were the survival of after-second year females, followed by juvenile survival and success of the first nest. For white-tailed ptarmigan, juvenile survival had the highest elasticity followed by success of the first nest and survival of second-year females. Incorporating stochasticity into the demographic rates led to a 2 and 4% drop in λ for rock and white-tailed ptarmigan respectively. Using data from the first three years we also found that population growth rates of both species were depressed following an increased frequency of severe years, but less so for rock ptarmigan which showed greater resilience under these conditions.ConclusionsOur results provide evidence that populations of closely related species can vary in their response to environmental change as a consequence of life history differences. Rock ptarmigan, with a slower life history, are more responsive to demographic rates that influence survival and older life stages but this response is tempered by the extent of variability in each of the rates. Thus, predictions need to consider both aspects in modeling population response to a varying climate. Juvenile survival was a highly influential rate for both species, but the period from independence to first breeding is a poorly understood stage for many bird species. Additional study on juvenile survival, the influence of density dependence and the effects of predators as the mechanism driving survival-reproduction tradeoffs are all areas requiring further study.

Reproductive strategy and ethnic conflict: Slow life history as a protective factor against negative ethnocentrism in two contemporary societies.

Much previous theory and evidence in both social and evolutionary psychology has been equivocal and inconsistent regarding whether in-group altruism should predict out-group hostility, and whether this effect should be positive or negative in direction. A Life History (LH) strategy emphasizes both kin-selected altruism and reciprocal altruism as means of investing heavily in offspring, blood relatives, and mutualistic social relationships with both kith and kin. We therefore investigated whether a slow LH strategy, as a measurable individual-difference variable favoring in-group altruism (positive ethnocentrism), should predict out-group hostility (negative ethnocentrism), and what the direction of the hypothesized effect would be. We found that a multivariate latent variable representing slow LH strategy served as a protective factor against a latent variable representing Negative Ethnocentrism. These results were replicated in the United States of America and in the Republic of Costa Rica using Multisample Structural Equation Model with cross-sample equality constraints.

Life History strategy and Evaluative Self-Assessment

Life History (LH) theory describes the existence of individual differences in the optimal allocation of inherently limited bioenergetic and material resources towards different types of reproductive-enhancing activities. LH theory predicts that slow LH (“High- K”) individuals are biased toward allocating resources toward enhancing the phenotypic quality (e.g., physical and mental health) of oneself and one’s offspring. Sociometer theory suggests that self-esteem tracks an individual’s level of social acceptance and inclusion. We examined the hypothesis that slow LH strategy positively predicts a more positive Evaluative Self-Assessment due to enhanced phenotypic quality. Participants completed questionnaires measuring their Life History (LH) strategies and a variety of measures of Self-Assessment (perceived mate value, perceived mating success, social economic exchange, positive and negative adjectives, global self-esteem, and collective self-esteem). An Exploratory Factor Analysis indicated that the measures of Evaluative Self-Assessment were best represented as a single latent factor. Slow LH strategy correlated moderately and positively with this Evaluative Self-Assessment factor. This relationship was not accounted for by socially desirable responding (self-deceptive enhancement or impression-management), sex, or age of participants. Consistent with Sociometer theory, we suggest that slow LH strategists exhibit high perceived self-worth due to increased social prestige and, relatedly, enhanced phenotypic quality.

Evidence for Shared Genetic Dominance Between the General Factor of Personality, Mental and Physical Health, and Life History Traits

We reanalyze previously published data on 309 MZ and 333 DZ twin pairs aged 25 to 74 years from the MIDUS survey, a nationally representative archived sample, to examine how much of the genetic covariance between a general factor of personality (GFP), a lower-order life history factor, and a general physical and mental health factor, is of the nonadditive variety. We found nonadditive genetic effects (D) could not be ruled out as a contributor to the shared variance of these three latent factors to a Super-K Life History factor. We suggest these genetic correlations support the view that a slow (K-selected) life history strategy, good health, and the GFP coevolved and are mutually coadapted through directional selection.

Life History Strategy and Disordered Eating Behavior

A sample of female undergraduates completed a packet of questionnaires consisting of the Arizona Life History Battery, a modified version of the Eating Disorders Inventory, the Behavioral Regulation scales from the Behavior Rating Inventory of Executive Function, and two measures of Female Intrasexual Competitiveness that distinguished between competition for mates and competition for status. As predicted, Executive Functions completely mediated the relation between Slow Life History Strategy and Disordered Eating Behavior. Surprisingly, however, the relation between Female Intrasexual Competitiveness (competition for mates and competition for status) and Disordered Eating Behavior was completely spurious, with executive functions serving as a common cause underlying the inhibition of both Disordered Eating Behavior and Female Intrasexual Competitiveness. The protective function of Slow Life History Strategy with respect to Disordered Eating Behavior apparently resides in a higher degree of Behavioral Regulation, a type of Executive Function. The enhanced Behavioral Regulation or self-control, of individuals with a Slow Life History Strategy is also protective against hazardously escalated levels of Female Intrasexual Competitiveness.

Height among Women is Curvilinearly Related to Life History Strategy

It was hypothesized that women of medium height would show a more secure, long-term mating pattern characterized by less jealousy, less intrasexual competition and a “slower” life history strategy. In three samples of female undergraduate students clear support was found for these hypotheses. In Study 1, among 120 participants, height was curvilinearly related to well-established measures of possessive and reactive jealousy, with women of medium height being less jealous than tall as well as short women. In Study 2, among 40 participants, height was curvilinearly related to intrasexual competition, with women of medium height being less competitive towards other women than tall as well as short women. In Study 3, among 299 participants, height was curvilinearly related to the Mini-K, a well-validated measure of “slower” life history strategy, with women of medium height having a slower life history strategy than tall as well as short women. The results suggest that women of medium height tend to follow a different mating strategy than either tall or short women. Various explanations and implications of these results are discussed.

Moral intuitions and religiosity as spuriously correlated life history traits

Religions promote moral rules of behavior and religiosity is associated with some types of moral intuitions, but there is no ultimate-level explanation for this association. Religiosity has recently been used as an indicator of a multivariate measure of slow Life History (LH) strategy. In this study, we predicted that LH strategy relates to increased strength of moral intuitions as measured by morally dumbfounding intuitions, reactions to violations of the ethics of autonomy, community, and divinity, and disgust sensitivity. Results of an exploratory factor analysis revealed that a 3-factor solution was optimal: (1) Religiosity (2) Moral Intuitions, (3) LH strategy. Comparisons of three path-analytic structural models indicated that only one model had an acceptable fit. In that model, slow LH strategy directly influenced religiosity and moral intuitions, which were, as a result, spuriously correlated. We discuss implications for LH theory and for the relation between religion and moral intuitions.

Egg size variation among tropical and temperate songbirds: An embryonic temperature hypothesis

Species with "slow" life history strategies (long life, low fecundity) are thought to produce high-quality offspring by investing in larger, but fewer, young. Larger eggs are indeed associated with fewer eggs across taxa and can yield higher-quality offspring. Tropical passerines appear to follow theory because they commonly exhibit slow life history strategies and produce larger, but fewer, eggs compared with northern species. Yet, I show here that relative egg mass (corrected for adult mass) varies extensively in the tropics and subtropics for the same clutch size, and this variation is unexplained. I propose a hypothesis to explain egg size variation both within the tropics and between latitudes: Relative egg mass increases in species with cooler egg temperatures and longer embryonic periods to offset associated increases in energetic requirements of embryos. Egg temperatures of birds are determined by parental incubation behavior and are often cooler among tropical passerines because of reduced parental attentiveness of eggs. Here, I show that cooler egg temperatures and longer embryonic periods explained the enigmatic variation in egg mass within and among regions, based on field studies in tropical Venezuela (36 species), subtropical Argentina (16 species), and north temperate Arizona (20 species). Alternative explanations are not supported. Thus, large egg sizes may reflect compensation for increased energetic requirements of cool egg temperatures and long embryonic periods that result from reduced parental attentiveness in tropical birds.

Does Life History Predict Risk-Taking Behavior of Wintering Dabbling Ducks?

AbstractLife-history theory predicts that longer-lived, less fecund species should take fewer risks when exposed to predation than shorter-lived, more fecund species. We tested this prediction for seven species of dabbling ducks (Anas) by measuring the approach behavior (behavior of ducks when approaching potential landing sites) of 1099 duck flocks during 37 hunting trials and 491 flocks during 13 trials conducted immediately after the 1999–2000 waterfowl hunting season in California, USA. We also experimentally manipulated the attractiveness of the study site by using two decoy treatments: (1) traditional, stationary decoys only, and (2) traditional decoys in conjunction with a mechanical spinning-wing decoy. Approach behavior of ducks was strongly correlated with their life history. Minimum approach distance was negatively correlated with reproductive output during each decoy treatment and trial type. Similarly, the proportion of flocks taking risk (approaching landing sites to within 45 m) was positively correlated with reproductive output. We found similar patterns of approach behavior in relation to other life-history parameters (i.e., adult female body mass and annual adult female survival rate). Thus, species characterized by a slower life-history strategy (e.g., Northern Pintail [A. acuta]) were more risk-averse than species with a faster life-history strategy (e.g., Cinnamon Teal [A. cyanoptera]). Furthermore, although we were able to reduce risk-averseness using the spinning-wing decoy, we were unable to override the influence of life history on risk-taking behavior. Alternative explanations did not account for the observed correlation between approach behavior and life-history parameters. These results suggest that life history influences the risk-taking behavior of dabbling ducks and provide an explanation for the differential vulnerability of waterfowl to harvest.

DOES LIFE HISTORY PREDICT RISK-TAKING BEHAVIOR OF WINTERING DABBLING DUCKS?

Life-history theory predicts that longer-lived, less fecund species should take fewer risks when exposed to predation than shorter-lived, more fecund species. We tested this prediction for seven species of dabbling ducks (Anas) by measuring the approach behavior (behavior of ducks when approaching potential landing sites) of 1099 duck flocks during 37 hunting trials and 491 flocks during 13 trials conducted immediately after the 1999–2000 waterfowl hunting season in California, USA. We also experimentally manipulated the attractiveness of the study site by using two decoy treatments: (1) traditional, stationary decoys only, and (2) traditional decoys in conjunction with a mechanical spinning-wing decoy. Approach behavior of ducks was strongly correlated with their life history. Minimum approach distance was negatively correlated with reproductive output during each decoy treatment and trial type. Similarly, the proportion of flocks taking risk (approaching landing sites to within 45 m) was positively correlated with reproductive output. We found similar patterns of approach behavior in relation to other life-history parameters (i.e., adult female body mass and annual adult female survival rate). Thus, species characterized by a slower life-history strategy (e.g., Northern Pintail [A. acuta]) were more risk-averse than species with a faster life-history strategy (e.g., Cinnamon Teal [A. cyanoptera]). Furthermore, although we were able to reduce risk-averseness using the spinning-wing decoy, we were unable to override the influence of life history on risk-taking behavior. Alternative explanations did not account for the observed correlation between approach behavior and life-history parameters. These results suggest that life history influences the risk-taking behavior of dabbling ducks and provide an explanation for the differential vulnerability of waterfowl to harvest.

Phylogeny and life histories of the ‘Insectivora’: controversies and consequences

The evolutionary relationships of the eutherian order Insectivora (Lipotyphla sensu stricto) are the subject of considerable debate. The difficulties in establishing insectivore phylogeny stem from their lack of many shared derived characteristics. The grouping is therefore something of a 'wastebasket' taxon. Most of the older estimates of phylogeny, based on morphological evidence, assumed insectivore monophyly. More recently, molecular phylogenies argue strongly against monophyly, although they differ in the extent of polyphyly inferred for the order. I review the history of insectivore phylogenetics and systematics, focussing on the relationships between the six extant families (Erinaceidae--hedgehogs and moonrats, Talpidae - moles and desmans, Soricidae - shrews, Solenodontidae--solenodons, Tenrecidae--tenrecs and otter-shrews and Chrysochloridae--golden moles). I then examine how these various phylogenetic hypotheses influence the results of comparative analyses and our interpretation of insectivore life-history evolution. I assess which particular controversies have the greatest effect on results, and discuss the implications for comparative analyses where the phylogeny is controversial. I also explore and suggest explanations for certain insectivore life-history trends: increased gestation length and litter size in tenrecs, increased encephalization in moles, and the mixed fast and slow life-history strategies in solenodons. Finally, I consider the implications for comparative analyses of the recent strongly supported phylogenetic hypothesis of an endemic African clade of mammals that includes the insectivore families of tenrecs and golden moles.

The breeding biology of palm cockatoos (Probosciger aterrimus): a case of a slow life history

AbstractThe breeding of palm cockatoos Probosciger aterrimus was studied for 3 years from July 1999 to February 2002 in and around Iron Range National Park, Cape York Peninsula, Australia. Palm cockatoos were weakly seasonal breeders, with the peak of egg‐laying occurring in September; 41 breeding attempts were monitored at 28 nesting hollows. Nearly all (27/28) nests were in tropical savanna woodland and an average distance of 320 m to rainforest. Males defended about four nest sites, only a subset of which were used for breeding. The typical active nest tree was in a near‐vertical hollow with an opening that faced skywards; 62.1% of active nests were in living trees and the most common species of nest tree was Eucalyptus tetrodonta (48.3%). DNA fingerprinting revealed that some pairs reused the same nest hollow even when breeding attempts were separated by 1 or more years of no breeding activity, but that changes in hollow ownership also occurred. Nest usurpation, male territorial displays at the nest and evidence of interference competition by conspecifics suggest strong competition for nest sites, which is probably driven by variation in hollow quality and high investment in the nesting platform. Of active nests, 81% failed to produce a fledgling, thereby ranking the breeding success of palm cockatoos among the lowest reported for any species of parrot. They also invariably laid a single egg and seemed to breed infrequently, and thus they use an extremely slow life‐history strategy. We suggest that this slow life history makes palm cockatoos on Cape York Peninsula sensitive to environmental perturbations, with fire being the most probable threatening process.

Average IQ values in various European countries

Finland has been noted to perform consistently very well in the international PISA assessments for many years, but it also has a relatively low per capita number of Nobel Prize winners. We draw upon a large body of proxy data and direct evidence, including the first ever use of RTs to calculate the Finnish IQ and the first ever use of the WAIS IV and PISA scores in the same capacity. Based on these data, we hypothesize that Finns perform so consistently well in PISA because they have a higher IQ overall than other European countries and exhibit a specialized slow life history strategy characterized by high Agreeableness and Conscientiousness, and low Psychoticism and Extraversion. Most of these traits predict educational success but all would suppress genius and creativity amongst this population. We connect the present distribution of phenotypic traits amongst the Finnish population with evolutionary change starting in the Pleistocene, accelerating in the Holocene, and continuing into the present day. We argue that this profile explains why Finns are relatively poorly represented in terms of science Nobel laureates.