Table 1: Chromosomal homolog Rice 2 3 vs Rice 4,6 7,10,12 vs Maize 5 1 vs Wheat 6 4 R2~=R4+R6; R3~=R7+R10+R12; R2~=M5;R3~=M1; R2~=W6;R3~=W4; It's sure that a chromosomal rearrangement event occured. Question 1: How? Question 2: When?