A potentially significant contribution of the Affordance Management Framework (AMF) is how a person’s life-stage goals drive their navigation of ecological affordances. The goal at every stage, however, is directly related to immediate or long-term reproductive success: in childhood, “somatic maintenance and growth”; in the mating life stage, “mate attraction and reproduction”; in the parenting stage, “optimizing quantity and quality of offspring and maintaining mate retention.” Although reproductive success is the endgame of any evolutionary theory of human behavior, the AMF is different. Whereas most evolutionary theories focus on specific adaptation-enhancing behaviors (e.g., Öhman & Mineka, Reference Öhman and Mineka2001), the AMF is a model of human development across the life span. In all stages, the aforementioned reproduction-related goals direct the navigation of ecological affordances. This makes the AMF a heteronormative and assiduously evolutionary model of human development. The complexity of development is reduced to strategies for increasing the odds of gene transportation. Moreover, it is not valid to equate adaptive development with accomplishing reproduction-related goals. People who do not reproduce can be developmentally well-adjusted, and producing offspring can increase risk for psychopathology, particularly in parents with a history of childhood trauma (Uy et al., Reference Uy, Tan, Broeckman, Gluckman, Chong, Chen, Fortier, Meaney and Callaghan2023).

The AMF differs from most evolutionary models in another critical respect. Evolutionary theories explain how behaviors promoted adaptation in the ancestral environment in psychological, experience-near terms. Reproductive success is a distal consequence of these adaptation-enhancing behaviors, which are mediated by psychological mechanisms. For example, developmentalists view the AMF’s goals for childhood (somatic maintenance and growth) as products of the child-caregiver attachment relationship. The child cries in distress and seeks the caregiver; the caregiver attunes and responds to the child’s cries; optimally, the child experiences relief and feels security, the caregiver relief in turn. These attachment behaviors have psychological functions and consequences that promoted fitness in the ancestral environment of evolutionary adaptiveness. Thus, child-caregiver attachment became a product of natural selection.

In the AMF, however, the proximal function of behaviors is to accomplish reproduction-related goals. This results in peculiar formulations that suggest the brain directly computes the odds of a behavior’s reproductive success, obviating its psychological function. For example, emerging adults address “the challenges of high genetic relatedness by (a) heightening their sensitivity to avoid inbreeding risks, (b) increasing contact with non-kin, and (c) relocating to an environment with a lower kin prevalence.” Accounts like these, which only detail how behaviors increase the likelihood of reproductive success, beg the psychological question an evolutionary theory is supposed to answer: why would emerging adults engage in these behaviors? What are the psychological mechanisms and reinforcements? Addressing these questions requires reconceptualizing the AMF’s life-stage goals, as I develop below.

These two problems with the AMF – equating development with reproduction-related goals, and its lack of psychological rationale – are illustrated by recent research findings. During the AMF’s mating stage, emerging adults “invest in embodied capital (body size, strength, skill) that will contribute to long-term reproductive success.” To researchers who study the current generation of young adults, these goals sound rather alien. Young adults are increasingly choosing not to have children, especially because they believe they cannot afford them (APA, 2024a). This decision relates to how young adults globally are struggling developmentally, as evidenced by several findings that similarly resist explanation by the AMF.

Previously, studies found that happiness peaked in young adulthood. In the last decade, eleven studies in several countries found significant declines in young adults’ life satisfaction and happiness (Twenge & Blanchflower, Reference Twenge and Blanchflower2025). In the inaugural wave of data from the Global Flourishing Study, more than 200,000 young adults ages 18–29, in twenty-two culturally diverse countries, reported poor physical and mental health, financial insecurity, a lack of meaning and purpose in life, low quality of interpersonal relationships, and negative perceptions of themselves (VanderWeele et al., Reference VanderWeele, Johnson, Bialowolski, Bonhag, Bradshaw, Breedlove and Yancey2025). The 2024 Lancet Psychiatry Commission reported that the mental health of young adults, which has been steadily declining for two decades, “has entered a dangerous phase.” Rates of anxiety disorders, depression, and substance disorders are alarmingly high in several countries and surging across demographic groups, suggesting “global megatrends…long-lasting social, economic, political, and/or technological changes in many societies around the world.” The Commission proposed the field of youth mental health be expanded to include ages 18–25, viewing emerging adulthood as a critical period for the ongoing emergence and intensification of psychopathology (McGorry et al., Reference McGorry, Mei, Dalal, Alvarez-Jimenez, Blakemore, Browne and Killackey2024).

Financial insecurity is a major driver of young adults’ poor psychological health (Villaume, Chen, & Adam, Reference Villaume, Chen and Adam2023). This relates somewhat to the AMF’s goal of building “embodied capital.” Otherwise, it does not seem useful to understand emerging adults’ developmental struggles in these terms. Studies identify three other major drivers: (1) a lack of purpose and meaning in life (VanderWeele et al., Reference VanderWeele, Johnson, Bialowolski, Bonhag, Bradshaw, Breedlove and Yancey2025); (2) loneliness and a lack of belonging (Buecker et al., Reference Buecker, Mund, Chwastek, Sostmann and Luhmann2021); and (3) pernicious social and political conditions, for example, unequal wealth distribution, climate change, loss of faith in democracy, and gun violence (APA, 2024b; Foa et al., Reference Foa, Klassen, Wenger, Rand and Slade2020, Hickman et al., Reference Hickman, Marks, Pihkala, Clayton, Lewandowski, Mayall and Van Susteren2021). A national survey by the Harvard Graduate School of Education implicated all three of these factors: 58% of young adults reported their mental health was compromised by “a lack of meaning or purpose in life,” 45% by “not mattering to others,” 44% “a general sense that things are falling apart,” and 40+% social and political conditions (Weissbourd et al., Reference Weissbourd, Batanova, McIntyre and Torres2023).

These driving factors shift the developmental focus to how young adults navigate ecological affordances related to identity, friendship, and belonging. These interrelated motives have an evolutionary basis (Azoulay et al., Reference Azoulay, Wilner-Sakal, Zabag and Gilboa-Schechtman2022; Moffett, Reference Moffett2013) and are essential to adaptation in emerging adulthood and adolescence. Thus, they are likely psychological mechanisms that promote long-term reproductive success. Developmentalists are similarly compelled to consider the psychological consequences for young adults when they cannot, as the AMF contends, “restructure their environment” – change the deleterious social and political conditions noted above. Hopelessness is a killer in emerging adulthood (Shahar et al., Reference Shahar, Bareket, Rudd and Joiner2006; Tonkus, Çalışkan, & Alagöz, Reference Tonkuş, Çalışkan and Alagöz2022), and hope is a protective mediator that enables young people to find purpose and translate it into happiness (Cottonbronk et al., Reference Cottonbronk, Hill, Lapsley, Talib and Finch2009).