Fig. 1From: On the consistency of orthology relationshipsExample of an constraint graph (G=(V,M⊎U),s), with s(a 1)=s(a 2)=A,s(b 1)=s(b 2)=B,s(c 1)=s(c 2)=C,s(d 1)=s(d 2)=D. The mandatory edges M are solid; the unknown edges U are dashed. Reduction Rule 1 will delete the unknown edge d 1 a 2 Back to article page