Ecology has often been treated as a main effect variable in the behavioral sciences, whether invoked to explain state-, trait-, group-, or cross-temporal differences in people’s thinking and behavior (Schaller & Murray, Reference Schaller and Murray2008; Sng et al., Reference Sng, Neuberg, Varnum and Kenrick2018; Varnum & Grossmann, Reference Varnum and Grossmann2017; Wormley et al., Reference Wormley, Kwon, Barlev and Varnum2023). Ko and Neuberg’s core argument is that the affordances posed by ecological conditions vary as a function of age and sex, and therefore, responses in terms of vigilance to ecological conditions and strategies for managing them should also vary accordingly. The authors focus on three key life stages, but note that other life stages may also need to be taken into account. Here, we turn our attention to one of these other stages, namely old age, and consider implications for responses to three ecological conditions – violence, pathogen threat, and sex ratio.

Physical violence is expected to be an environmental dimension that has similar affordance implications for both sexes later in life. During earlier phases of adulthood, physical violence poses largely different affordances for men and women. While men are statistically more likely to be victims of physical violence (Daly & Wilson, Reference Daly and Wilson1988), women show greater fear toward and perceive themselves at higher risk of victimization from crime and physical violence (Fetchenhauer & Buunk, Reference Fetchenhauer and Buunk2005; May, Rader, & Goodrum, Reference May, Rader and Goodrum2010), and generally place greater value in security and self-protection than men do (Ko et al., Reference Ko, Kenrick, Becker and Varnum2025; Leijen, van Herk, & Bardi, Reference Leijen, van Herk and Bardi2022). This pattern can likely be explained by sex differences in physical formidability (e.g., Kerry & Murray, Reference Kerry and Murray2018; Kerry & Murray, Reference Kerry and Murray2021; Manson et al., Reference Manson, Chua, Rodriguez, Barlev, Durkee and Lukaszewski2023), as, on average, men have substantially greater upper-body strength than women (Bartolomei et al., Reference Bartolomei, Grillone, Di Michele and Cortesi2021; Landen et al., Reference Landen, Hiam, Voisin, Jacques, Lamon and Eynon2023; Miller et al., Reference Miller, Balshaw, Massey, Maeo, Lanza, Haug, Johnston, Allen and Folland2024). Furthermore, women may be more motivated to avoid physical danger than men, given women’s greater obligate parental investment and slower mating strategies (Kokko & Jennions, Reference Kokko and Jennions2008; Trivers, Reference Trivers1996). While these sex differences are likely to hold for most of the adult lifespan, men tend to lose strength at a faster rate than women as they age, causing sex differences in strength to decrease in old age (Nahhas et al., Reference Nahhas, Choh, Lee, Chumlea, Duren, Siervogel, Sherwood, Towne and Czerwinski2010; Oksuzyan et al., Reference Oksuzyan, Maier, McGue, Vaupel and Christensen2010). Thus, violence should have similar affordance implications and be met with similar management strategies for men and women in older age. For example, men’s self-protection concerns may also increase at a faster rate than women’s, narrowing the gap between the sexes in terms of vigilance to violence. Indeed, men show increasing fear of crime (Johansson & Haandrikman, Reference Johansson and Haandrikman2023) and value security more as they age (Leijen et al., Reference Leijen, van Herk and Bardi2022). We would also expect that older adults of both sexes to use similar strategies to mitigate the threat of physical violence, such as relying on physically formidable others and avoiding situations where violence is perceived as more likely.

The affordance implications of pathogens should also become more similar for the sexes in older age. Although women tend to have more robust immune systems than men, younger women face greater fitness costs from illness, given their higher investment in offspring and slower life-history strategy (Kokko & Jennions, Reference Kokko and Jennions2008; Trivers, Reference Trivers1996; Landolt, Lalumière, & Quinsey, Reference Landolt, Lalumière and Quinsey1995). These fitness costs may be especially high during reproductively viable years for women (Sappenfield, Jamieson, & Kourtis, Reference Sappenfield, Jamieson and Kourtis2013; Creisher & Klein, Reference Creisher and Klein2024). This may explain why young women exhibit significantly higher disgust sensitivity and heightened vigilance toward pathogens compared to young men (Berthold et al., Reference Berthold, Bearth, Ammann and Siegrist2025; Tybur et al., Reference Tybur, Bryan, Lieberman, Caldwell Hooper and Merriman2011). However, sex differences in disgust sensitivity diminish, ultimately disappearing in the mid-70s. Men’s disgust sensitivity tends to increase with age, likely reflecting their rising vulnerability to pathogens, while women’s disgust sensitivity remains relatively stable, potentially because the effects of heightened vulnerability to illness are offset by reduced fitness costs after menopause (Berthold et al., Reference Berthold, Bearth, Ammann and Siegrist2025). Moreover, Berthold et al. (Reference Berthold, Bearth, Ammann and Siegrist2025) found similar age-related trends in behavioral immune system traits such as food neophobia and contamination fear, further supporting the prediction that the affordance implications of pathogen threat converge between the sexes in old age. Extending this reasoning, we predict that other sex differences in behavioral immune responses – such as aversion to novelty, conformity, and xenophobia – will likewise diminish later in life.

Nevertheless, the convergence in late adulthood between the sexes in affordance implications and responses to ecological conditions may not occur for all facets of ecology. In the case of sex-age ratio, sex differences may be expected to persist well into late adulthood. Although older women experience menopause, men do not necessarily lose the capacity for reproduction. As such, mating motives may remain more salient for men than women in late adulthood (Buunk et al., Reference Buunk, Dijkstra, Kenrick and Warntjes2001; Kenrick & Keefe, Reference Kenrick and Keefe1992). Expanding on the current framework, we hypothesize that older men could still manage their affordances in ways similar to younger men – by maintaining increased vigilance toward the operational sex ratio in order to further mating opportunities – while we would predict that postmenopausal women would show decreased attention to this ecological feature. Overall, we find it reasonable to predict that some divergences in affordance implications of ecological dimensions, linked to persistent physiological asymmetries between men and women, should persist well into late adulthood despite other convergences.

In addition to converging in their own affordance management strategies for some ecological conditions, older men and women may also become more similar in the affordances they pose to others. Changes in affordance management strategies, age-related physiological shifts, and stereotypes should lead to older men and women being perceived as offering more similar affordances (e.g., willingness to engage in alloparenting, warmth, incompetence, and nonthreatening presence) compared to earlier stages of adulthood (Cuddy, Norton, & Fiske, Reference Cuddy, Norton and Fiske2005; Cuddy & Fiske, Reference Cuddy and Fiske2002; Shakeri & North, Reference Shakeri and North2025).

In conclusion, Ko and Neuberg’s present framework adds important nuance to our understanding of how human behavior is shaped by ecology, highlighting interactions among ecological affordances, age, and sex. By extending that framework to consider life stages beyond parenting, which typically occurs during humans’ 20s to early 50s, we can gain insight into how the sexes may converge or diverge in responses to ecological conditions across the lifespan.