Crossed lines. Eve's family tree may have a few branches from Adam.
Ross
P E
PE
D000349:Africa; D000818:Animals; D005075:Biological Evolution; D004272:DNA, Mitochondrial / Q000032:analysis / Q000235:genetics; D005260:Female; D015186:Hominidae / Q000235:genetics*; D006801:Humans; D008297:Male; D051379:Mice
D004272:DNA, Mitochondrial