WEBVTT 00:00.000 --> 00:06.267 By 8 weeks, 75% of embryos exhibit right-hand dominance. 00:06.300 --> 00:08.233 The remainder is equally divided 00:08.267 --> 00:12.700 between left-handed dominance and no preference. 00:12.733 --> 00:19.333 This is the earliest evidence of right- or left-handed behavior.