“…Although some research shows, with weak to moderate effect sizes, that younger people have stronger environmental concerns than older people (e.g., Buttel and Flinn, 1978 , r = −0.30; Howell and Laska, 1992 ; Jones and Dunlap, 1992 ; Li and Chen, 2018 , b = −0.03; Nord et al, 1998 , β = −0.42; Vaske et al, 2011 ), other researchers either found no significant relationship between age and environmental concern (e.g., Gray et al, 2019 ), or instead found that age was positively, although weakly, related to environmental concern (e.g., Echavarren, 2017 , β = 0.01; Hirsh, 2010 , β = 0.13; Huddart-Kennedy et al, 2015 , β= −0.03 to 0.12; Lewis et al, 2019 ; β= −0.40 to 0.50). There is also evidence from a large-scale, multi-country analysis, that the relationship between age and environmental concern may be weakening compared to earlier decades, at least in affluent countries ( VanHeuvelen and Summers, 2019 ), perhaps due to increased exposure to environmental issues in the media ( Howell and Laska, 1992 ), a finding that aligns with research of Americans from 1966 to 2009 showing that young people are becoming more concerned with money and status, and less concerned about the environment than previous generations were ( Twenge et al, 2012 , with moderate to large effect sizes). Therefore, the evidence in relation to the age hypothesis seems to be weak and mixed.…”