Table 2.

Typical tenets of life-history theory as presented in the introductions of papers from psychology.

tenet	description	example
(i)	trade-offs exist	‘according to LHT, the finite nature of resources available to organisms during evolution induced multiple-trait trade-offs among fitness components such as current versus future reproduction and offspring quality versus quantity’ [21, p. 1] ‘LHT posits that organisms face important trade-offs in how they allocate….resources among the several competing demands of life….’ [22, p. 889]
(ii)	life-history traits covary between individuals along a fast–slow continuum	‘LHT suggests that humans fall along a spectrum from early reproduction and allocation of resources toward mating effort, to later reproduction and devotion of resources toward somatic and parental effort…referred to as the fast–to–slow life history continuum’ [23, p. 933] ‘Life history strategies vary along a fast/slow continuum’ [24, p. 23] ‘From the perspective of LHT, a mid-level evolutionary framework, [behavioural] phenotypic variables are conceptualized as indicators of individual differences along a fast–slow LH continuum’ [25, p. 1]
(iii)	people adapt to their personal environments, especially those of childhood, by becoming ‘faster’ or ‘slower’.	‘LHT predicts that people calibrate their reproductive strategies to local levels of environmental harshness and unpredictability…’ [26, p. 434] ‘according to LHT….the nature of an individual's childhood environment disposes that individual to adopt a fast or a slow life history strategy….’ [27, p. 621] ‘these ‘fast’ versus ‘slow’ life history trajectories are strategic responses to the particular environment in which people find themselves’ [28, p. 891] ‘according to LHT, exposure to harshness and/or unpredictability early in life should promote a fast life history strategy’ [29, p. 1542]
(iv)	specific predictions	‘the evolutionary framework of LHT predicts that preferences for risk and delay in gratification should be influenced by mortality and resource scarcity’ [30, p. 1015] ‘LHT predicts that an array of [crime-related] behaviors will shift in response to life expectancy cues’ [31, p. 12] ‘LHT suggests that adult reward sensitivity should be best explained by childhood, but not current, socioeconomic conditions’ [32, p. 48] ‘the evolutionary framework of LHT predicts that preference for delay of gratification should be influenced by social economic status’ [33, p. 1]