Evolutionary psychology seeks to identify and understand human psychological traits that have evolved in much the same way as biological traits, through adaptation to environmental cues. Furthermore, it tends toward viewing the vast majority of psychological traits, certainly the most important ones, as the result of past adaptions, which has generated significant controversy and criticism from competing fields. These criticisms include disputes about the testability of evolutionary hypotheses, cognitive assumptions such as massive modularity, vagueness stemming from assumptions about the environment that leads to evolutionary adaptation, the importance of non-genetic and non-adaptive explanations, as well as political and ethical issues in the field itself.